Hippophae rhamnoides L. has been widely used in research and application for almost two decades. While significant progress was achieved in the examination of its fruits and seeds, the exploration and utilization of its by-products have received relatively less attention. This study aims to address this research gap by investigating the effects and underlying mechanisms of sea buckthorn seed residues both in vitro and in vivo. The primary objective of this study is to assess the potential of the hydroalcoholic extract from sea buckthorn seed residues (HYD-SBSR) to prevent cell apoptosis and mitigate oxidative stress damage. To achieve this, an H2O2-induced B16F10 cell model and a D-galactose-induced mouse model were used. The H2O2-induced oxidative stress model using B16F10 cells was utilized to evaluate the cellular protective and reparative effects of HYD-SBSR. The results demonstrated the cytoprotective effects of HYD-SBSR, as evidenced by reduced apoptosis rates and enhanced resistance to oxidative stress alongside moderate cell repair properties. Furthermore, this study investigated the impact of HYD-SBSR on antioxidant enzymes and peroxides in mice to elucidate its reparative potential in vivo. The findings revealed that HYD-SBSR exhibited remarkable antioxidant performance, particularly at low concentrations, significantly enhancing antioxidant capacity under oxidative stress conditions. To delve into the mechanisms underlying HYD-SBSR, a comprehensive proteomics analysis was conducted to identify differentially expressed proteins (DEPs). Additionally, a Gene Ontology (GO) analysis and an Encyclopedia of Genes and Genomes (KEGG) pathway cluster analysis were performed to elucidate the functional roles of these DEPs. The outcomes highlighted crucial mechanistic pathways associated with HYD-SBSR, including the PPAR signaling pathway, fat digestion and absorption, glycerophospholipid metabolism, and cholesterol metabolism. The research findings indicated that HYD-SBSR, as a health food supplement, exhibits favorable effects by promoting healthy lipid metabolism, contributing to the sustainable and environmentally friendly production of sea buckthorn and paving the way for future investigations and applications in the field of nutraceutical and pharmaceutical research. Hippophae rhamnoides L., commonly known as sea buckthorn or seaberry, boasts a widespread distribution across Asia, Europe, and North America [Elaeagnaceae family and has been traditionally used in a wide range of fields, such as foods, pharmaceuticals, and cosmetics [ America . It beloosmetics . The divosmetics ,4. Of noosmetics ,6,7. Nevosmetics ,9,10,11.Despite the promising potential of SBSR for various applications, a comprehensive exploration of its practical utility in raw material development is lacking. Furthermore, the choice of extraction methods can lead to variations in the composition and efficacy of the resulting extracts. Commonly used solvents for SBSR extraction include water and ethanol. Previous studies indicated that aqueous SBSR extracts exhibit hypoglycemic and hypolipidemic effects in type 2 diabetic rats induced with streptozotocin and a high-fat diet . In addiNumerous in vitro studies have extensively validated the antioxidant capacities of SBSR. These investigations encompass a range of assays, including the estimation of reactive oxygen species generation, measurement of enzymatic/non-enzymatic antioxidant activities/levels, evaluation of peroxisome proliferator-activated receptors levels, and assessment of 3-ethylbenzothiazoline-6-sulfonic acid (ABTS) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activities ,15. HoweIn recent years, flow cytometry has undergone significant advancements, enabling the identification of multiple phenotypic subsets, the selection of individual cells, and even cell isolation using sorting. This technology plays a pivotal role in clinical settings by identifying aberrant cells, quantifying excessive or reduced populations of specific cells, and monitoring changes in tracked cell populations . In thisB16F10 cells, a melanoma cell line derived from mice, possess high metabolic activity leading to reactive oxygen species (ROS) production, potential stress response activation, rapid growth facilitating timely observations, and relevance to simulating disease-related conditions ,21. ThesHippophae rhamnoides L.) seed residues (HYD-SBSR) at the cellular and physiological levels while establishing a correlation between in vitro and in vivo experimental findings. This not only supports the broader application of sea buckthorn seed by-products in food but also addresses environmental concerns linked to sea buckthorn production, thereby contributing to sustainable and eco-friendly industrial development.Prior research has demonstrated that sea buckthorn seed products can contribute to reducing blood glucose and lipid levels in obese mice ,24. Using and 4 °C for 15 min. The resulting supernatant was collected, and the extraction process was repeated twice to enhance the yield and purity of the extracted components. The collected supernatants from each extraction were combined to create a consolidated sample. The ethanol in the sample was subsequently removed using rotary evaporation under vacuum conditions at a controlled temperature of 40 °C. This evaporation process facilitated solvent removal, concentration of the extracted substances, and conversion into a fine powder. The collected HYD-SBSR was stored securely for future investigations. The flavonoid, procyanidin, and total phenolic contents reached up to 354.00 ± 21.00 mg RE per g DW, 319.31 ± 11.70 mg CE per g DW, and 271.24 ± 91.30 mg GAE per g DW, respectively [HYD-SBSR was prepared following the methodology outlined in . Ground ectively .2.B16F10 cells  were cultured in Dulbecco’s Modified Eagle Medium , supplemented with 10% heat-inactivated fetal calf serum, and a 1% antibiotic–antimycin solution consisting of 100 units/mL penicillin /streptomycin and 100 U/mL amphotericin  at 37 °C in a humidified incubator  under 5% CO2 for 12 h. The cells were treated with H2O2 or HYD-SBSR at different concentrations for a period. Details of the concentration values are provided in Cell viability was determined using a dimethylthiazole-2-yl)-2,5-diphenyltetrazolium bromide  assay. B16F10 cells were seeded into a 96-well plate at a concentration of 5000 cells per well at 37 °C and were incubated in a cell incubator with 5% COThe MTT assay involved the addition of a 100 μL mixture of MTT solution (5 mg/mL) and DMEM at a volumetric ratio of 1:5. This treatment was carried out for 4 h, followed by the addition of 150 μL of DMSO to dissolve the resulting products. After a 10-minute incubation at 37 °C, the absorbance was measured at a wavelength of 490 nm to determine the results. t represents the experimental group absorbance minus zeroing group absorbance and OD0 represents the control group absorbance minus zeroing group absorbance. Cell viability was calculated following the equation below.2O2).A model of acute ROS-induced B16F10 cells was established using a 4-hour treatment with hydrogen peroxide for a duration of 4 h to establish the H2O2-induced cell oxidative stress model. Subsequently, the cells were subjected to treatment with varying concentrations of HYD-SBSR  for a period of 24 h. The group of cells without any HYD-SBSR treatment served as the model group for comparison.The experimental procedure involved the treatment of B16F10 cells with H5 were planted in a six-well plate and incubated overnight. Cells were treated with HYD-SBSR  for 24 h and then treated with H2O2 (8.8 mM) for 4 h. Only cells treated with HYD-SBSR were used as the HYD-SBSR control. Cultured cells were washed with PBS. The cells were lysed using 200 µL Western and IP cell lysis buffer , followed by a 12,000× g centrifugation for 10 min to collect the supernatant. The contents of GSH-Px, CAT, SOD, and MDA were then determined in a 96-well plate , according to the instructions of the GSH-Px, CAT, SOD, and MDA detection kit . Protein content was measured using a BCA protein kit from Beyotime. The contents of these parameters were calibrated using the protein content and expressed as micrograms per milligram of protein.Cells at a density of 1 × 10Annexin V-PE is a fluorescently labeled protein that binds to calcium-dependent phospholipids with a strong affinity for phosphatidylserine (PS) binding sites, similar to Annexin V-FITC. During the early stages of cell apoptosis, the loss of membrane symmetry exposes PS on the outer surface of the cell membrane. In both the early and late stages of apoptosis, PS is present on the outer surface of the cell membrane. Importantly, early apoptotic cells maintain membrane integrity, preventing the entry of 7-AAD. In contrast, late apoptotic cells exhibit compromised membrane integrity and can be co-stained with Annexin V-PE or V-FITC and 7-AAD. This staining method allows for the differentiation and identification of cells at different stages of apoptosis based on variations in phospholipid exposure and membrane integrity ,27.In this study, cell death was detected and analyzed with flow cytometry using FACS Calibur .5 cells per well in a 6-well plate, with 3 wells per group. The model group was initially exposed to 8.8 mM H2O2 for 4 h, followed by treatment with 0.1 mg/mL HYD-SBSR for 24 h. Conversely, the HYD-SBSR group underwent the opposite treatment sequence. Then, cells from each group were harvested using trypsin digestion for subsequent analyses. After treatment, approximately 10,000 cells were obtained from each sample. Staining of cell samples was performed using Annexin V-PE and 7-AAD . Experimental data were obtained and analyzed using CellQuest . Annexin V-PE and 7-AAD fluorescence  were used for two-parameter point plots. Seeding was performed with a cell density of 1.5 × 10Cell populations were separated as follows: viable cells-Annexin V-PE-negative and 7-AAD-negative ; early apoptotic cells-Annexin V-PE-positive and 7-AAD-negative ; late-apoptotic cells or dead cells- Annexin V-PE-positive and 7-AAD-positive ; and cells debris-Annexin V-PE-negative and 7-AAD-positive . The proportion of 4 groups was calculated using FlowJo software . The total apoptosis rate was calculated by summing the rate of early apoptotic cells and late apoptotic cells.Mus musculus).A D-galactose-induced aging mice model was established to investigate the protective effect of HYD-SBSR. The experiment was conducted using specific pathogen-free (SPF)-grade Institute of Cancer Research (ICR) male mice (n = 10): control group, model group, HYD-SBSR high-dose group (HYD-SBSR-H), HYD-SBSR medium-dose group (HYD-SBSR-M), and HYD-SBSR low-dose group (HYD-SBSR-L). Each group contained 10 mice.Fifty male SPF ICR mice with an average body weight of (23 ± 3) g were ordered from Beijing Vital River Laboratory Animal Technology Co., Ltd.  and acclimated for one week. They were then randomly divided into 5 groups . Control-group mice received an equivalent volume of 0.9% physiological saline. The low-dose, medium-dose, and high-dose groups were orally administered 100, 300, and 600 mg/(kg body weight) of HYD-SBSR, respectively. The control and model groups were administered an equivalent volume of physiological saline. The treatment duration lasted 42 days. Throughout the intragastric administration period, the mice were maintained in an environment with a temperature of 22 to 25 °C, relative humidity of 50% to 60%, and a 12-hour light (08:00–20:00) and 12-hour dark cycle under fluorescent illumination. Bedding was changed every 3 days. All mice received a standard diet and had access to water.No mice experienced mortality over the course of the entire experiment, and all subjects were included in this study. The Guide for the Care and Use of Laboratory Animals  was strictly followed in designing all animal experimental procedures. Ethical approval for all animal experiment procedures was granted by the Experimental Animal Welfare Ethics Committee of Beijing Experimental Animal Research Center (BLARC-2017-A015).w/v) ratio with pre-chilled physiological saline, which was centrifuged at 3 000 r/min and 4 °C for 15 min. The supernatants were removed to determine tissue biochemical indexes . All indexes were determined following the manufacturer’s instructions.Following euthanization with cervical dislocation, segments of liver and brain tissues were frozen in liquid nitrogen first and then homogenized under an ice bath to prepare 10% homogenate in a 1:9 . The whole process included protein sample preparation, TMT labeling, high-performance liquid chromatography (HPLC) fractionation, liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis, and proteomics data analysis. A detailed protocol for this analysis is provided in the p-value < 0.05.The DEPs satisfied the following conditions: average ratio-fold change >1.1 (up-regulation) and <0.9 (down-regulation) and a http://www.geneontology.org/ Map each term of org/, accessed on 20 July 2023), where the count of proteins for each term was calculated. Subsequently, hypergeometric tests were applied to pinpoint GO entries that exhibited substantial enrichment among the differential proteins, relative to the genome background. After multiple tests and corrections, GO terms with a p-value of ≤0.05 were considered significantly enriched in the set of differential proteins. These DEPs were then categorized into three primary classifications, namely, biological process (BP), cell component (CC), and molecular function (MF). The KEGG database was used to identify enriched pathways. A two-tailed Fisher’s exact test was used to evaluate the enrichment of DEPs relative to all the identified proteins within specific pathways. A pathway achieving a corrected p-value of < 0.05 was deemed to be significant. These pathways were subsequently classified into hierarchical categories in accordance with the KEGG website’s structure.Functional classification of the DEPs was performed according to the Gene Ontology (GO) annotation and enrichment analysis. The Encyclopedia of Genes and Genomes (KEGG) Orthology-Based Annotation System (KOBAS) v2.0 was used. The enrichment analysis of GO function significance unveiled functional categories that exhibited significant enrichment in the pool of differential proteins in comparison with the broader genomic background. This analysis entailed the submission of all differential proteins to the GO database  and GraphPad Prism 9.0  software. Single factor ANOVA analysis was used for comparisons between groups, and a 2O2 on cell viability and the induction of oxidative stress in B16F10 cells were investigated. An MTT assay was used to assess the viability of B16F10 cells exposed to varying concentrations of H2O2, ranging from 0.4 to 44.1 mM. The results demonstrated that as the dose of H2O2 increased, cell viability progressively decreased  %. Therefore, the oxidative stress model was established using the conditions of 8.8 mM H2O2 exposure for a duration of 4 h.The impact of Hecreased . ConversThe investigation delved into the impact of varying concentrations of HYD-SBSR (ranging from 0.05 to 0.4 mg/mL) on the viability of B16F10 cells A. Remark2O2-induced oxidative stress. The examination encompassed assessments of cell viability  compared with their respective control group. The pre-treatment with HYD-SBSR at 0.1 mg/mL  and lipid peroxidation products, such as MDA content, were detected. 2O2 and HYD-SBSR, as well as pre- and post-treatment strategies in H2O2-induced models. In comparison with the control group, a discernible trend emerged that the GSH-Px, CAT, and SOD levels notably decreased, while the MDA content exhibited a marked increase in the model group (p < 0.01). Conversely, cells treated solely with HYD-SBSR demonstrated minimal alterations in these indices (p > 0.05), with the exception of CAT (p < 0.05), as compared to the control group.As illustrated in 2O2 exposure (H2O2 + HYD-SBSR treatment) yielded a substantial increase in the levels of cellular enzymes  (p < 0.01) coupled with a reduction in MDA contents (p < 0.01) when contrasted with the model group. This intervention resulted in the GSH-Px, CAT, SOD, and MDA contents reaching values of (303.06 ± 19.24) mU/mg protein, (107.95 ± 1.29) mU/mg protein, (237.27 ± 21.98) mU/mg protein, and (8.12 ± 0.96) μmol/g protein, respectively, indicative of the potential reparative influence of HYD-SBSR. Similarly, the pre-treatment regimen involving HYD-SBSR (HYD-SBSR + H2O2 treatment) displayed a comparable trend. However, it was noted that the enhancement of GSH-Px, CAT, and SOD levels was relatively subdued, and the inhibition of MDA was less pronounced compared with the post-treatment strategy using HYD-SBSR.Significantly, the post-treatment with HYD-SBSR following HD-galactose-induced aging mice were utilized to investigate antioxidant enzyme and peroxide levels in vivo. The continuous administration of D-galactose led to disturbances in glucose metabolism within mice cells, disrupting the body’s antioxidant defense system and resulting in the accumulation of free radicals. This, in turn, triggered oxidation reactions leading to the production of substances like LP and MDA, culminating in bodily aging.p < 0.01), effectively confirming the successful establishment of the D-galactose-induced aging model.Apart from assessing the total antioxidant capacity (T-AOC), the activities of key antioxidants, including SOD, GSH-Px, and CAT, offered direct insight into the body’s ability to counteract free radicals. For the analysis, liver and brain tissues were collected from mice to measure these antioxidant enzyme and peroxide levels . In compp < 0.01). However, no statistically significant differences were observed between the HYD-SBSR-M group and the model group (p > 0.05). Conversely, for brain tissue, no noteworthy distinctions were evident between the three doses of HYD-SBSR and the model group (p > 0.05). As depicted in p < 0.01), surpassing that in the model group (551.00 ± 41.85 U/mg protein). In contrast, medium and high doses of HYD-SBSR did not significantly affect liver CAT activities when compared to the model group (p > 0.05). However, a substantial impact of HYD-SBSR on CAT activity in brain tissue was evident, showing values of 42.42 ± 6.64 U/mg protein as compared with the model group. Notably, all three doses of HYD-SBSR significantly enhanced brain CAT activity (p < 0.01) in a dose-dependent manner. p < 0.05). No significant differences were observed in liver SOD activities between HYD-SBSR-H and the model group (p > 0.05). Similar patterns emerged for brain SOD activities, showcasing a dose-dependent trend. Medium- and high-dose groups (HYD-SBSR-M and HYD-SBSR-H) displayed significantly elevated brain SOD activities (p < 0.01) compared with the model group, whereas no substantial differences were observed between the HYD-SBSR-L and model groups (p > 0.05).Turning to liver SOD activities C, both tp < 0.01; brain, p < 0.05). HYD-SBSR treatment brought about a significant enhancement in T-AOC levels within the liver and brain tissues. T-AOC levels in the HYD-SBSR-L group surpassed those in the model group . However, no statistically significant differences in T-AOC levels were observed between the HYD-SBSR-M and HYD-SBSE-H groups and the model group (p > 0.05).The total antioxidant capacities (T-AOC) of both liver and brain tissues in the model group were notably lower than those in the control group . After HYD-SBSR treatment, the levels of LP and MDA in liver and brain were lower than those in the model group (p < 0.01).The levels of MDA D and LP p-value as pivotal criteria (FC ≥ 1.1 or ≤0.9 and p ≤ 0.05). In comparison with the control group, the model group exhibited a set of 79 DEPs, among which 32 were upregulated and 47 were downregulated  protein database, a comprehensive total of 5510 reliable proteins were identified under conditions with less than a 1% false discovery rate (FDR). egulated . Similaregulated . Intriguegulated . Among tegulated .p < 0.05). Among the top five enriched GO terms were processes such as catecholamine metabolic process, positive regulation of cholesterol biosynthetic process, cellular response to glucagon stimulus, amino acid binding, and carboxylyase activity. In the comparison between the model and HYD-SBSR groups, the DEPs significantly influenced 9 BP, 10 CC, and 10 MF categories (p < 0.05). Among the top five enriched GO terms were processes like negative regulation of intestinal phytosterol and cholesterol absorption, 3′-phosphoadenosine 5′-phosphosulfate biosynthetic process, sulfate adenylyl transferase (ATP) activity, ATP-binding cassette (ABC) transporter complex, and adenylyl sulfate kinase activity.We performed GO enrichment analysis separately on the DEPs identified in the control versus model group A and thep < 0.05). In the analysis of the control vs. the model group (p < 0.05), including selenocompound metabolism, PPAR signaling pathway, lysosome, ABC transporters, metabolic pathways, fat digestions and adsorption, glycerophospholipid metabolism, complement and coagulation cascades, cholesterol metabolism, and sulfur metabolism.Further analysis revealed the enriched KEGG pathways  demonstrated the opposite expression pattern. Of significance among the DEPs is the protein Aga, also referred to as aspartylglucosaminidase, a lysosomal enzyme that starts as an inactive precursor molecule and is swiftly activated within the endoplasmic reticulum . An Aga Eef1e1, also known as eukaryotic translation elongation factor 1 ε 1, plays a role in protein synthesis and cell differentiation ,32. It pMoreover, Farp1 was identified as one of the guanine nucleotide exchange factors, which belongs to a family of regulatory proteins for Rho GTPases, influencing various cellular processes . Farp1 iPigr (polymeric immunoglobulin receptor precursor) is a single transmembrane protein. Its expression was subsequently upregulated after HYD-SBSR treatment. The impact on the MEK/ERK pathway suggests potential attenuation of liver injury in mice .Regarding the GO and KEGG pathway analyses, our findings revealed that HYD-SBSR significantly influences GO terms related to mitochondria, lipid storage, triglyceride homeostasis, ATP-binding cassette (ABC) transporter complex, and more. Enriched KEGG pathways in the HYD-SBSR group compared with the model group encompass the PPAR signaling pathway, fat digestion and absorption, glycerophospholipid metabolism, and cholesterol metabolism. These pathways are closely associated with the body’s antioxidant status and changes in MDA and LP indicators. PPARs, in particular, play a pivotal role in lipid metabolism, mitochondrial function, and antioxidant defense, helping mitigate oxidative stress . Enhance2O2 on B16F10 cells, aiming to assess the potential cytoprotective and repair effects of HYD-SBSR. The results we obtained pointed toward a decrease in apoptosis rates and an improvement in resistance to oxidative stress upon treatment with HYD-SBSR. Additionally, our findings suggested that HYD-SBSR exhibited significant properties in terms of facilitating cell repair.In this study, we initiated our research by creating an oxidative stress model using HBy incorporating the outcomes of antioxidant enzyme and peroxide analyses at the cellular level, further investigations were conducted to evaluate the impact of HYD-SBSR on antioxidant enzymes and peroxides in mice. The results exhibited significant antioxidant performance, particularly at lower concentrations of the extract, suggesting a potent ability to enhance antioxidant capacity.To delve into the underlying mechanisms, we carried out a comprehensive proteomics analysis to identify proteins that were differentially expressed upon HYD-SBSR treatment. Subsequently, GO and KEGG pathway analysis were used to reveal the mechanism pathways associated with HYD-SBSR. Noteworthy pathways included PPAR signaling, fat digestion and absorption, glycerophospholipid metabolism, and cholesterol metabolism. These insights provide a deeper understanding of the cellular and molecular processes that underlie the observed cytoprotective and antioxidant effects of HYD-SBSR.A comparison of in vitro and in vivo research findings demonstrated a consistent alignment. The inclusion of HYD-SBSR into food products not only addresses sustainability concerns in sea buckthorn production but also has the potential to enhance lipid metabolism within the organism. Furthermore, we speculate that it might even contribute to healthy weight management for individuals.


Precision medicine is growing as an innovative approach in the neuroendocrine field, aiming to obtain a detailed understanding of the disease, including epigenetic and omics characterization, to ultimately improve patient care , 2. NeurNeuroendocrine tumors: the road to precision medicine”, in the Frontiers in Endocrinology Journal, is dedicated to collecting high-quality scientific contributions that mainly focus on recent advances in the context of the diagnosis, treatment, and prognosis of NETs.The current Research Topic, “Xu W et al. elaborates an easy-to-use web-based calculator to predict the overall survival of MCC patients. This tool is based on a nomogram including key prognostic variables. The study by Luo S et al. shows that F-PNETs incidence decreased over the study period (2000-2017). In addition, the statistical Cox proportional hazards model identifies tumor size, tumor stage, tumor type, and surgical resection as the main prognostic factors for F-PNETs.With these premises, two studies in the current Research Topic present an analysis of epidemiological data collected from the Surveillance, Epidemiology, and End Results (SEER) database in two challenging subtypes of NET; Merkel cell carcinoma (MCC), a highly aggressive neuroendocrine carcinoma, which correlates with poor prognosis; and functional pancreatic NET (F-PNETs), a heterogeneous group of pNET associated with the clinical diagnosis of hormonal hypersecretion and syndrome. In both cases, the main aim is to assess and further predict patients’ survival outcomes. Specifically, the work by Fanciulli G et al. summarize the available in vitro and in vivo data on the role of PrIn as monotherapy as well as in combination with other treatments for MTC. Their review highlights that despite the encouraging preclinical activity of PrIn in in vitro studies in human and murine MTC cell lines, evidence in the clinical setting is currently scarce. The authors advocate the launch of new clinical trials to establish the potential usefulness of these agents for MTC.One study in the current Research Topic, by Fanciulli, is focused on the assessment of a new potentially relevant class of drugs for medullary thyroid cancer (MTC), proteasome inhibitors (PrIn). Sira L et al. describe the case of a young woman with non-functioning advanced pNET associated with the mutation of JAK2V617F, which is an independent factor for thromboembolic events. The patient presented at first with massive portal and splenic vein thrombosis, requiring anticoagulation treatment. Three years later, she was diagnosed with a grade 2 (Ki-67 index of 6%) pNET, associated with unresectable liver metastases. In this case, the surgical removal of the pancreatic tumor was performed and systemic treatment with somatostatin analogs (SSA) was started. The treatment was stopped for the duration of the patient’s two pregnancies and then started again. Notably, after parturition, a complete remission of the liver lesions was achieved. Whole Exome Sequencing (WES) was performed but failed to demonstrate a mutation in MEN1, VHL, NF1, TSC1, TSC2, MUTYH, BRCA2, and CHEK2 genes. The second case report, by Tarris G et al., describes a giant (88 x 73 mm) F-PNET in a young woman. The diagnostic work-up was started due to the onset of hypoglycemia unresponsive to treatment with diazoxide. A CT scan detected the mass located in the pancreatic tail, which was surgically removed. At the histopathological evaluation, a grade 1 (Ki-67 < 2%) pNET with cytoplasmic expression of insulin in tumor cells was found, confirming the diagnosis of insulinoma. After a 16-month follow-up period after pancreatic surgery, the clinical symptoms were recovered and the patient was found to be free from disease recurrence.Finally, two case reports are published within this Research Topic. In conclusion, this Research Topic highlights recent advances in precision medicine in NET, including rare primaries such as MCC and MTC. The various contributions in this Research Topic demonstrate how the development of patient-tailored treatment approaches is evolving in the neuroendocrine field. This will likely result in better patient care and survival thanks to personalized treatments. We believe this Research Topic has the potential to support specialists involved in treating NEN.Neuroendocrine tumors: the road to precision medicine”. All authors contributed to the article and approved the submitted version.ALS, DG, and RM contributed to the development of this article by summarizing the results of all scientific manuscripts included in the Research Topic “


Molecular property prediction is a crucial task in various fields and has recently garnered significant attention. To achieve accurate and fast prediction of molecular properties, machine learning (ML) models have been widely employed due to their superior performance compared to traditional methods by trial and error. However, most of the existing ML models that do not incorporate 3D molecular information are still in need of improvement, as they are mostly poor at differentiating stereoisomers of certain types, particularly chiral ones. Also,routine featurization methods using only incomplete features are hard to obtain explicable molecular representations. In this paper, we propose the Stereo Molecular Graph BERT (SMG-BERT) by integrating the 3D space geometric parameters, 2D topological information, and 1D SMILES string into the self-attention-based BERT model. In addition, nuclear magnetic resonance (NMR) spectroscopy results and bond dissociation energy (BDE) are integrated as extra atomic and bond features to improve the model’s performance and interpretability analysis. The comprehensive integration of 1D, 2D, and 3D information could establish a unified and unambiguous molecular characterization system to distinguish conformations, such as chiral molecules. Intuitively integrated chemical information enables the model to possess interpretability that is consistent with chemical logic. Experimental results on 12 benchmark molecular datasets show that SMG-BERT consistently outperforms existing methods. At the same time, the experimental results demonstrate that SMG-BERT is generalizable and reliable. Recently, Machine Learning (ML), including Deep Learning (DL), has emerged as a powerful data-driven approach for establishing a connection between molecular structure and properties  by integrating the 3D space geometric parameters, 2D adjacency information, and 1D SMILES representation into a self-attention-based BERT model. SMG-BERT could generate accurate chemical representations for various molecules, including chiral molecules, which provides assurance for precise property prediction results and expands the application scope. Meanwhile, SMG-BERT incorporates the NMR chemical shifts and bond dissociation energies (BDEs) as chemical descriptors using a transformer encoder to improve interpretability. This results in visualizations that conform to chemical logic and are more convincing. A series of experimental results show that SMG-BERT can consistently outperform previous state-of-the-art molecular property prediction models on 12 benchmark molecular datasets.In this section, we describe in detail the data preprocessing process, model structure, and loss function in three parts. In the data preprocessing process, the model could obtain an input representation that consists of three components: a molecular representation z of the molecules (2) the bond dissociation energy matrix B,(3) and the distance fraction matrix D.In the pre-training process, the dataset was collected from PubChem . AlthougThe input representationof the molecules: we used RDKIT to transform each SMILES into an atomic sequence ous work   as the loss function to compute the difference between the predicted values and the corresponding ground truth values for atomic distances Loss functions: To balance the different objective functions represented by tal loss , and areSeveral advanced models in recent years were selected for comparison as the baseline, namely, GAT , GIN Xu, D-MPNN R2 are used as evaluation indicators for classification and regression tasks, respectively.A total of 12 datasets (seven for regression and five for classification) were selected from MoleculeNet  and ADMEThe architecture of our model is shown The resulting molecular representation would be used for downstream tasks and would adopt the fine-tuning method. Specifically, after pre-training, the atom representation of the global super-node “<G>” is the final molecular representation, with a 512-dimensional vector. This would be fed into a two-layer, fully connected network with random initialization, which yields the final prediction results. The network uses ReLU as the activation function and sets the dropout ratio to 0.1. Considering that catastrophic forgetting issues could occur as the model targets specific downstream tasks that are completely different from the pre-training process , we woulR2 increased by 5.07% in On the other hand, stereochemical molecules deserve our special attention because they are a rarely studied class of molecules in nature. Current DL models often overlook chiral pair discrimination, leading to inaccurate predictions . AlthougThis dataset was divided into training, validation, and test sets in a ratio of 8:1:1. As shown in 15H12O) as a case study. We also presented visualization results for several molecules.In the final phase of our study, we examined the attention matrix generated by SMG-BERT to reveal the chemical insight acquired during pre-training. We calculated the similarity between attentional scores for atoms at different levels of information integration, using the benzophenone molecule , which integrates a number of molecular features, including 3D spatial geometric parameters, 2D adjacency information, and 1D SMILES representation, into a self-attention-based BERT architecture. Additionally, SMG-BERT incorporates NMR chemical shifts and BDEs as chemical descriptors through a transformer encoder, which improves interpretability and results in visualizations that are chemically consistent and more compelling As the result shows, SMG-BERT generates accurate chemical representations for various molecules, including chiral molecules, ensuring precise property prediction results and expanding the scope of applications. In contrast, our work focuses exclusively on chiral pairs, meaning that only compounds with a chiral center were considered, while chiral centers in sulfur or phosphorus were excluded. Diastereomers and atropisomers were not taken into account in this work, as diastereomers are not mirror images, and the conformation of atropisomers is typically not described in most activity databases.


The prevalence of type 2 diabetes (T2D) has been growing worldwide; hence, safe and effective antidiabetics are critically warranted. Recently, imeglimin, a novel tetrahydrotriazene compound, has been approved for use in T2D patients in Japan. It has shown promising glucose-lowering properties by improving pancreatic beta-cell function and peripheral insulin sensitivity. Nevertheless, it has several drawbacks, including suboptimal oral absorption and gastrointestinal (GI) discomfort. Therefore, this study aimed to fabricate a novel formulation of imeglimin loaded into electrospun nanofibers to be delivered through the buccal cavity to overcome the current GI-related adverse events and to provide a convenient route of administration. The fabricated nanofibers were characterized for diameter, drug-loading (DL), disintegration, and drug release profiles. The data demonstrated that the imeglimin nanofibers had a diameter of 361 ± 54 nm and DL of 23.5 ± 0.2 μg/mg of fibers. The X-ray diffraction (XRD) data confirmed the solid dispersion of imeglimin, favoring drug solubility, and release with improved bioavailability. The rate of drug-loaded nanofibers disintegration was recorded at 2 ± 1 s, indicating the rapid disintegration ability of this dosage form and its suitability for buccal delivery, with a complete drug release after 30 min. The findings of this study suggest that the developed imeglimin nanofibers have the potential to be given via the buccal route, thereby achieving optimal therapeutic outcomes and improving patient compliance. Diabetes remains among the leading causes of morbidity and mortality, resulting in enormous burdens on healthcare systems worldwide . The gloSeveral promising therapeutics for the treatment of T2D have been developed over the past recent years, and among these is imeglimin . It is aTreatment with imeglimin has demonstrated good safety and efficacy outcomes ,7,14,15.Similarly, the pediatric population may experience similar problems when achieving optimal therapeutic outcomes . Such isOral and buccal delivery has several advantages, including ease of administration, fast absorption, bypassing first-pass metabolism, and low GI absorption ,22. DiffThe current study is aimed to fabricate electrospun imeglimin nanofibers with the ultimate goal of having a novel imeglimin formulation that provides rapid disintegration and absorption rates via the buccal route. The imeglimin nanofibers will be prepared by the electrospinning technique and characterized for their fibrous diameter, drug-loading, disintegration and drug-release profile. The fabricated imeglimin-loaded nanofibers will have several advantages over conventional imeglimin, including ease of administration and patient compliance in geriatric and pediatric populations and avoidance of GI-related adverse responses. In addition, the nanofiber formulation will have other benefits, such as faster absorption rates, the onset of action, and bypassing drug first-pass metabolism in the liver.Polyvinylpyrrolidone (PVP) with an average molecular weight of ~1,300,000, ethanol , methanol (HPLC grade), acetonitrile (HPLC grade), and phosphate buffer saline tablets  were supplemented from Sigma-Aldrich , while triethanolamine was purchased from Loba Chemie . PBS solution was prepared by adding 5 tablets in one-liter distilled water and mixing until completely dissolved; then, the pH was adjusted to 6.8 using 5M hydrochloric acid. Imeglimin hydrochloride (CAS No. 775351-61-6) was bought from Med Chem Express . Imeglimin (purity: 99.98%) has a molecular weight of 191.66 and a water and DMSO solubility of ≥50 mg/mL and 25 mg/mL, respectively . The che® electrospinning setup , according to a modified method [w/v) concentration and stirred at room temperature for 2 h until the complete dissolving of the PVP polymer. The imeglimin was mixed with the polymer solution in a 1% (w/v) concentration and stirred for an hour to allow for homogeneity between the drug and the polymer solution. PVP solution, alone as 8% (w/v), without adding the drug, was used as a blank  formulation. The electrospun nanofibers were formulated at room temperature and 30–45% relative humidity. The electrospinning setup syringe pump was adjusted at a flow rate of 800 µL/h, a needle-to-collector distance of 15 cm, and an inner needle diameter of 0.9 mm. To achieve a stable jet, a voltage in the 7–9 kV range was applied, and the surface of the metallic collector was covered with aluminum foil to collect the prepared nanofibers. PVP is a water-soluble, non-toxic, biocompatible polymer approved for use in the pharmaceutical industry by the United States Food and Drug Administration (US FDA). Hence, it is widely used in medicine and cosmetics [Imeglimin-loaded nanofibers fabrication was performed using the Spraybased method . To prepThe prepared blank and drug-loaded nanofibers were characterized, in terms of surface morphology and diameter, using the scanning electron microscopy (SEM) instrument  at a 5 kV accelerating voltage and average measurements of 70 fibers for each fibrous system. The fabricated nanofibers were collected directly onto aluminum foil, and platinum (2 nm) was used to coat the samples in a JEC-3000FC auto fine coater . The nanofibers diameter analysis was measured using ImageJ software .® 2020 software  was employed to plot the patterns of XRD results.The XRD analysis of imeglimin, PVP, the physical mixture , blank, and drug-loaded fibers was performed using Rigaku Miniflex 300/600 . Cu Kα radiation (λ = 1.5148 227 Å) was equipped in the XRD instrument, with a current and voltage of 15 mA and 40 kV, respectively. All tested formulations were placed on glass holders and scanned between 2θ of 5° to 50° at a scan speed of 5°/min. OriginProThe blank and drug-loaded nanofibers disintegration was evaluated following a modified petri dish method . A total® 717 plus autosampler, Waters 600 binary pump, and Waters 2489 UV/detector . Imeglimin was separated by an isocratic elution of a mobile phase of triethanolamine , methanol, and acetonitrile at a ratio of 60%, 5%, and 35%, respectively, and a Waters XSelect HSS Cyano C18 column , with a temperature that was maintained at 20 °C. The flow rate of the mobile phase was adjusted at 1 mL/min, the injection volume was kept at 10 μL, and the detection was achieved at a wavelength of 254 nm.Imeglimin was quantified using the Waters e2695 HPLC system that consists of a WatersA stock solution of imeglimin was prepared by dissolving the drug into PBS (pH 6.8). A serial dilution ranging from 100 to 1.56 μg/mL was used to develop the imeglimin calibration curve according to the method mentioned above. The drug retention time (Rt) was achieved at 3.3 min.The DL of imeglimin-loaded nanofibers was measured by dissolving at least three pieces of the nanofibers (4.1 ± 0.1 mg) in 5 mL PBS (pH 6.8), and each solution was maintained at room temperature for 7 h to ensure complete nanofibers dissolution. The concentration and amount of imeglimin were measured using the developed HPLC method of detection, and the following equation calculated the DL:The following equation was applied to measure the Y of the imeglimin-loaded fibers:The number of theoretical nanofibers was quantified based on the number of solid materials (drug and polymer) in the total volume of the spinning solution. All the results are presented as mean ± SD of three independent replicates.The release profile of imeglimin-loaded nanofibers was identified by dissolving at least three pieces of the fibrous mat (9 ± 1 mg) into 10 mL of pre-warmed PBS (pH 6.8) in glass vials. A thermostatic shaking incubator  was used to determine the drug release of imeglimin-loaded nanofibers, with a temperature and shaking rate of 37 °C and 100 RPM, respectively. A total of 1 mL of the tested formulation was withdrawn at a predetermined time-point, ranging from 1 to 180 min, and substituted with an equivalent volume of pre-warmed PBS (pH 6.8). The imeglimin amount was quantified using the developed method of HPLC, and the cumulative release percentage was calculated as a function of time by the following equation:The results are presented as the mean ± SD of at least three independent replicates.®, San Francisco, CA, USA), was placed in between a donor and receptor chamber of the Franz diffusion apparatus. The latter chamber held 3 mL of pre-warmed PBS (pH 6.8), and the experiment was performed at 37 ± 0.5 °C with continuous stirring. At least three pieces of the fibrous mat (8 ± 0.5 mg) were placed into the donor chamber, and 0.5 mL PBS (pH 6.8) was added to dissolve the nanofiber mat. A total of 100 μL samples were withdrawn from the receptor compartment at a predetermined time-point ranging from 15 min to 24 h and substituted with an equivalent volume of pre-warmed PBS (pH 6.8). The imeglimin amount was quantified using the developed method of HPLC, and the cumulative release percentage was calculated as a function of time by Equation (3).The release of imeglimin-loaded nanofibers was also assessed by Franz diffusion . A piece of a semipermeable membrane, with a cut-off from 12 to 14 KD (spectra/por® Aqueous one solution cell proliferation assay) was purchased by Promega . It measured the cellular metabolic activity of human fibroblast HFF-1 cells (ATCC- SCRC-1401) following a 24 h exposure to the tested drug. HFF-1 cells were exploited in this study since it was previously reported as an in vitro model for drug delivery research of the oral mucosal cavity [v/v) fetal bovine serum (FBS) and additional essential components for media preparation; all were obtained from Sigma-Aldrich .The in vitro cytotoxicity of imeglimin was assessed using the MTS assay according to the modified method . The MTSl cavity ,33,34. C4 cells per well into a 96-well microtiter plate. HFF-1 cells were kept in the incubator at 37 °C and 5% CO2 overnight. A total of 100 µL of increasing dose of the imeglimin, from 15.6 to 1000 µg/mL, were exposed to the HFF-1 cells for 24 h. Cells incubated with DMEM only or 0.2% Triton X-100 were used as positive and negative controls, respectively. The consumed medium was aspirated from each well, and 100 µL of fresh DMEM plus 20 µL of the MTS reagent were added into the wells. The cells were incubated for 3 h at 37 °C and 5% CO2. A Cytation 3 microplate reader  was used at 492 nm to measure the absorbance of MTS, and the below equation calculated the percentage of cell viability:S is the absorbance of HFF-1 cells treated with imeglimin, T is the absorbance of HFF-1 cells treated with Triton X-100, and H is the absorbance of HFF-1 cells treated with cell culture media. The results are presented as the mean ± SD of at least three replicates.Trypan blue exclusion test was used for cell counting, and the cells were seeded at a seeding density of 1.5 × 10® 2020 software  was used to analyze the data statistically and plot the graphs presented in this study.OriginProThe morphology analysis of the blank and imeglimin-loaded nanofibers using SEM exhibited that the fabricated nanofibers had smooth, non-porous, and non-beaded surfaces, as shown in The physical state of raw materials , blank, and imeglimin-loaded nanofibers was examined using XRD and confirmed the solid dispersion of the drug owing to electrospinning. The disintegration test is considered an essential parameter for any oral cavity dosage forms such as sublingual and buccal medications, which should be ≤30 s, according to US FDA regulation . Figure 2) were determined as y = 81462x + 119483 and 0.9992, respectively, as shown in Imeglimin quantification was performed by a developed HPLC, where it showed a successful drug separation after 3.3 min , as presented in the The DL of the imeglimin-loaded nanofibers was measured by the above-developed HPLC method, which was calculated as 23.5 ± 0.2 µg/mg of the fibers. The data indicated that the Y of the drug-loaded nanofibers was quantified as 78%, and most likely the remaining percentage was lost during the peeling of the fibrous mat off the aluminum foil and the deposition of some fibers onto the walls of the electrospinning instrument chamber. This fibrous loss was also seen in previous PVP electrospun fibers studies .The release of imeglimin was evaluated by placing the drug-loaded nanofibers in glass vials using custom-made sinkers to be sunk in the bottom of the vials owing to the floating nature of the fibrous mats. The imeglimin-loaded nanofibers exhibited a burst release in the first minute i.e., 42%), followed by a cumulative drug release of 87% after 5 min, and a complete release of imeglimin appeared after 30 min, as presented in %, followImeglimin release was also assessed by the Franz diffusion cell method. As shown in Evaluating the loaded drug’s cytotoxicity is essential to assess its safety on living cells and prove its suitability for therapeutic applications. It is worth noting that owing to the FDA approval of PVP polymer for being considered a safe pharmaceutical excipient, this study did not assess the cytotoxicity of PVP. Different doses of imeglimin exposed to HFF-1 cells were evaluated over 24 h, and the result is demonstrated in In sum, the carried-out assessments in this study have demonstrated that imeglimin was successfully loaded into ultra-rapid disintegrating PVP electrospun nanofibers. The formulated imeglimin nanofibers had smooth, non-porous, and non-beaded surfaces with an average diameter of 361 ± 54 nm. The nanofibers exhibited a DL of 23.5 ± 0.2 μg/mg of the fibers, rapid drug release of about 87% after 5 min, and a complete drug release after 30 min. Such quick release is attributed to the hydrophilic nature of PVP, the large surface-to-volume ratios of the nanofibers, and their ultra-rapid disintegration rates (≤2 ± 1 s). Together, this study provides a novel delivery platform of imeglimin nanofibers with the potential to be administered via the buccal route with the advantage of overcoming existing challenges of free drugs, including suboptimal oral absorption and GI-associated adverse responses. In addition, this formulation can potentially enhance drug compliance in special populations, including geriatrics and pediatrics. Future studies are warranted to evaluate and validate the formulated nanofibers in relevant in vivo models.


Electrospun nanofiber mats are usually applied in fields where their high specific surface area and small pore sizes are important, such as biotechnology or filtration. Optically, they are mostly white due to scattering from the irregularly distributed, thin nanofibers. Nevertheless, their optical properties can be modified and become highly important for different applications, e.g., in sensing devices or solar cells, and sometimes for investigating their electronic or mechanical properties. This review gives an overview of typical optical properties of electrospun nanofiber mats, such as absorption and transmission, fluorescence and phosphorescence, scattering, polarized emission, dyeing and bathochromic shift as well as the correlation with dielectric constants and the extinction coefficient, showing which effects may occur and can be measured by which instruments or used for different applications. Electrospinning can be used to produce very fine fibers, typically in the range of some ten to some hundred micrometers, from a polymer solution or melt ,2,3. Usu3 nanofiber mats with different polymers which show a high photoluminescence intensity and can thus be used in highly luminescent white LEDs [All these aspects will influence the optical properties of nanofiber mats. Naturally, the structural properties of nanofiber mats will influence their optical properties, not only by the fiber diameter distribution, but also by defects . As usuaite LEDs .Measurements of the optical properties of such nanofiber mats are usually performed by spectrophotometric methods, often applying a UV-visible (UV/Vis) spectrometer, besides other techniques such as diffuse reflectance spectroscopic (DRS) measurements, etc. ,27,28. HOn the other hand, the impact of the environment on the optical properties of nanofibrous membranes makes them suitable as sensing devices, e.g., for toxicants, pH value, temperature, acids, volatile organic compounds, etc. ,31,32,33This review describes the different optical properties of electrospun nanofiber mats, measurement techniques, and potential applications, concentrating on the visible light spectrum and partly directly neighboring parts of the spectrum, where the latter is measured with the same instrument, e.g., a UV/Vis spectrometer.Abs is defined as −1, so that care must be taken comparing different studies [The absorption and the absorbance characterize the ability of a material to absorb light. The absorbance tigation . Absorpt studies .2 h).One of the fields in which broadband light absorption is important is light harvesting, e.g., for solar steam generation ,36,37. LOptical sensors can also be based on changes in absorption ,40,41. A2O3 nanofibers for photocatalytic tests and showed that by combining the two phases, α-Bi2O3 and β-Bi2O3, the band gap could be tailored, resulting in the possibility to optimize the degradation of Rhodamine B [2 nanofibers by electrospinning in a humid environment [4/WO3 composite nanofibers, which showed a clearly higher absorption edge compared to Ag/WO3 or WO3 solely, as depicted in 4/WO3 nanofibers /poly(ethylene oxide) (PEO) nanofibers filled with PbS nanoparticles and found a significantly increased absorption with increasing PbS content, combined with a blueshift of the reflectance onset, besides tenability of the band gap by the size of the PbS nanoparticles .While absorbance measurements are, as mentioned in this section, often used to tailor the absorbance edge towards higher wavelengths to reach better photocatalytic properties or for similar applications, these measurements can also be used to investigate the optical band gap of materials, as described in the next section.x-axis [y-axis is y-axis is chosen, while it is also possible to use both plots for immiscible blends with direct and indirect band gaps [The optical band gap of semiconductors is usually detected from absorption spectra by using Tauc plots. The band gap energy can be estimated according to the Tauc formula e sample ), the phnsitions . As showe x-axis . In the and gaps ,57. The and gaps ,57.2 nanofibers and nanotubes were identical within measurement accuracy, as shown by Wang et al. [Using this technique, Matysiak et al. characterized the different blends of poly(acrylonitrile) (PAN) with the conductive polymers polypyrrole (PPy), polythiophene (PT), and polyaniline (PAni) and found a reduction in the band gap of pure PAN (4.08 eV) to minimum 3.77 eV for composite nanofibers containing 3% PAni . Interesg et al. .2/CuS composite nanofibers as compared to CeO2 nanofibers, which was favorable for visible light-induced photodegradation of methylene blue [(1−x)MnxFe2O4 nanofibers with different x between 0 and 0.75 [2 nanowires in pure form or as composites with PVP showed band gaps varying with structure and material blend [Sabzehmeidani et al. showed a strong band gap shift of CeOene blue . Similarand 0.75 . Gea et and 0.75 . Similaral blend ,65.While the optical transmission through a sample is often calculated from absorbance measurements (and vice versa) by Lambert–Beer law e sample . While iAlthough both these values seem to be clearly correlated in theory, this law may cause practical problems, e.g., if reflection and scattering in the sample have to be taken into account, which are part of the extinction cf. , but notp-n junctions [In addition to these potential problems of calculating transmission from absorbance measurements, the literature research showed clearly that transmission measurements are mostly performed for different purposes, which is why this optical property is described in a separate section. Mostly, high transmission values are aimed at ,68, e.g.unctions , transpaunctions ,71, or sunctions .Liu et al. investigated nanofibrous polyurethane (PU) electret window screens used for air filtration and found transmission values of approx. 5–50%, depending on the wavelength and on the areal density of the nanofiber mats . Similar2, which were highly intransparent at different UV wavelengths as well as at 600 nm, while the pure PLA film showed a transmission around 67% [Another application of transparent nanofiber mats is given by edible films used for food packaging, which is why Ebrahimi et al. developed transparent gluten films containing nanofibers in which the nanofibers reduced the transparency, but at the same time eliminated the undesired yellowish color of the pure gluten films . On the ound 67% .Finally, it should be mentioned that the optical property of transparency is correlated with the electrical sheet resistance and other electrical properties ,80, whicWhile the complex dielectric function is defined as material . HoweverNevertheless, the dielectric constant of nanofiber mats is often investigated, e.g., by impedance measurements, which enable calculating  tangent ,83,84. H tangent ,86,87, sd [B nanofiber thin film, which they suggested for energy storage and solar cell applications [n and The extinction coefficient can be calculated by length λ ,89. The ckness d . Kenawy ications . Going foperties . Ibrahimoperties . For PANoperties .The real part of the refractive index is more often mentioned than the extinction. This is probably due to the high impact of scattering in nanofiber mats, usually causing a low transparency . TranspaWhile Fraunhofer diffraction is not applicable for nanofibers with diameters in the same order of magnitude as the impinging light wavelengths, the Mie theory—originally developed for small spherical particles—is often used with modifications, taking into account the anisotropic shapes of the nanofibers . Based o0.5Zn0.5Fe2O4 nanoparticles, to detect sunitinib, a cancer drug, from the change in the scattering intensity [In addition to these applications where scattering was improved or reduced, partly wavelength-dependent, it is also possible to use measurements of scattering properties for sensing. In this way, Pirdadeh-Beiranvand et al. used resonance light scattering (RLS) of PVA nanofibers, decorated with Nintensity . The autntensity ,104.Photoluminescence (PL) belongs to the often-mentioned optical properties of nanofiber mats ,106,107 3N4 nanofibers, which showed enhanced photocatalytic activity and light harvesting properties, as compared to the bulk material [3+ and Tb3+ ions, Deliormanli et al. found emission bands around 506 nm and 566 nm for an excitation wavelength around 374 nm, with additional bands for 1% Er3+ and more additional emission bands for Tb3+ or combinations of both dopants, showing different emission centers for the dopants [The photoluminescence spectrum, especially the maximum, can be influenced by the preparation of electrospun nanofiber mats, e.g., by the pyrolysis process of sulfur self-doped g-Cmaterial . For ele dopants . Investi dopants .4:Eu3+ were shown to have strong PL, making such nanofibers useful for optic and photonic devices [In addition to these investigations of the sample properties by photoluminescence, PL can also be used, e.g., for oxygen sensing by praseodymium-modified ZnO nanofibers , while P devices . Compari devices . Packagi devices .When a paper explicitly mentions fluorescence measurements, often optical sensors are the aim of the study . Such el2+ phosphorescent sensors [Phosphorescence, on the other hand, was suggested as an alternative to electrical light in medical endoscopes  or for a sensors ,141, pho sensors , or seve sensors .In most cases, the aforementioned spectroscopic measurements are not related to the polarization of the incident or the emitted/reflected light. Investigations by polarized light optical microscopy, however, may be used to investigate the molecular orientation within the nanofibrous membrane, as depicted in Polarized optical microscopy was used, e.g., by Thum et al. who embedded liquid crystals (LCs) in coaxially electrospun nanofibers with a PVP sheath and azobenzene-doped LC core ,148. TheAnisiei et al. used POM to roughly estimate the fiber crystallinity of chitosan/PEO and chitosan nanofibrous membranes . They foIn addition to polarized optical microscopy, Bernardo et al. reported about polarized second harmonic generation (SHG) of anisotropic poly-ε-caprolactone (PCL) nanofibers in which nonlinear nanocrystals were embedded . The setMeng et al. embedded halide perovskite nanocrystals in PVA nanofibers and measured their polarization by using a picosecond pulsed diode laser whose light was circularly polarized as an incident beam, which was focused on the sample by an inverted fluorescence microscope . The resUsing an isotropic exciting light source, Chen et al. found strong anisotropy for emission with polarization parallel or perpendicular to the axis of their poly (P3HT) nanofibers, with much higher emission intensity and a red-shifted maximum for the polarization perpendicular to the fiber axis .3 nanorods embedded in polystyrene (PS) nanofibers could be aligned by an external magnetic field applied during electrospinning [Fu et al. showed by polarized luminescence measurements that CsPbBrspinning .2 in DSSCs [The bathochromic shift is a red-shift of the absorption spectrum of a material, based on the assembly between conjugated polymer backbones . It is win DSSCs ,157,158,in DSSCs ,160,161.3L) (L = ligand) complex with Eu(NTA)3 embedded in PVA nanofibers, which they attributed to a coordination interaction with the ligand L [Philip et al., e.g., reported bathochromic shifts when they embedded silver nanoparticles in poly(methyl methacrylate) (PMMA) nanofibers, which was attributed to the impact of the surface plasmon resonance absorption bands of the Ag NPs . Similarligand L . Baptistligand L .H-phenothiazine-3carboxylate or rubidium 10-ethyl-10H-phenothiazine3-carboxylate got in contact with different solvents, also called solvatochromism [On the other hand, Kato et al. used the bathochromic shift of the absorption maximum of PMMA upon contact with methanol solutions containing anions, which they attributed to the hydrogen bond formation between urea in the polymer and the anions penetrating into the nanofibers, thus using the bathochromic shift for sensing . Similarchromism .3 concentrations [Oh et al. as well as Park et al. found bathochromic shifts of their meta-aramid/dye and cesium lead bromide perovskite nanofibrous membranes upon contact with ammonia, making these nanofiber mats suitable for ammonia sensing ,167. Thitrations .In addition to the aforementioned bathochromic shift, based on chemical reactions, nanofiber mats can also change their color when they are dyed. An often-applied process is adding a dye directly to the spinning solution, which should result in a colored nanofiber mat ,170,171.For PVA nanofiber mats, Fadil added Remazol Yellow FG dye and Ase Direct Supra Red BWS dye to the spinning solutions, respectively, resulting in yellow and red dyed nanofibers, while the direct dye Ase Direct Supra Red BWS contained relatively large molecules and thus strongly increased the average fiber diameters .Using cationic dyes, Yan et al. showed dyeing poly (PVB) nanofiber mats in different colors, here red, yellow, light-blue, and black, which kept the colors nearly unchanged for 6 months . Water-fBalakrishnan et al. chose alizarin, indigo, as well as different pigment dyes for dyeing PLA melt-electrospun nanofiber mats . They reReactive dyes were used by Kishimoto et al. who dyed chitin nanofibers with blue, red, yellow colors, and mixtures of them, resulting in colors which were resistant even to hot water and detergents .A combination of low IF emissivity and high solar absorption, useful for radiative heating of the human body in a cold environment, was reached by adding dyes to a PAN electrospinning solution, followed by magnetron sputtering a thin Ag layer on the electrospun nanofiber mat . The IR Jatoi et al. chose another path and dyed electrospun PCL nanofiber mats in a continuous (pad-dry-cure) as well as a semicontinuous (pad-batch) process with disperse dyes . They foWhile the optical properties of electrospun nanofiber mats are often ignored, in many cases they nevertheless enable investigations of their morphology, physical, and chemical properties. Transmission and absorbance can be tailored for the respective applications, while dyeing enables strong coloring in spite of the scattering of the mostly randomly oriented thin nanofibers. Furthermore, color changes of special nanofibrous materials can be used for sensing applications.Modern research in the field of materials develops not only due to the achievement of greater resolving power of instruments measuring the electronic, mechanical, electrical, and optical parameters, but mainly thanks to the introduction of innovations to the inner structure of materials. Particularly important for this development is the transition from classical, structurally continuous materials, such as a variety of alloys, into structurally discontinuous materials. This results in completely new, sometimes surprising features. In the case of electrospun materials, the fibrous structure forces new properties. In the case of interactions between nanofiber mats and electromagnetic waves, local effects result from the existence of internal reflections and dispersion, which reveal specific dielectric and optical properties of the material as a whole. Similarly, in terms of electro-optical properties and the coupled elastic and thermal effects which are typical for electronic devices, phenomena such as reflection, transport through material interfaces, and conduction of light along single fibers occur, and at the same time, attempts to technologically control the anisotropy of optoelectronic properties on the macro scale. Appropriate selection of the production parameters of these nanofiber mats introduces components of directionality, resulting in anisotropic as well as optically and spectroscopically dispersive properties of these innovative materials.While morphological or mechanical properties of electrospun nanofibrous membranes are often discussed, this review thus gives a brief overview of typical optical measurements which enable deeper characterization of nanofiber mats.


Morphological traits have been the most important targets for plant improvement in the long history of crop breeding, including the domestication of crops that occurred more than 10,000 years ago and current cutting-edge molecular breeding. Modification of morphological traits has improved various agronomically important traits in ancestral varieties and contributed to the breeding of high-yielding, agronomically superior varieties. Agronomic productivity is not solely determined by the final morphology of a crop. From sowing to harvest, the farmer’s care and management affect the growth and development of crops, and consequently productivity. In addition, it is crucial to understand how crop morphology changes in response to the environment and conditions. Therefore, crop developmental biology has been an important research area not only for curiosity-driven biological science but also for plant breeding and agriculture.Arabidopsis was first published as a model of higher plants, and that of rice was released in 2004 as a model crop. These led to the elucidation of the molecular entity of the semi-dwarf genes used in the Green Revolution (In the history of plant developmental biology, the promotion of molecular genetics in the 1990s and the genome decoding of higher plants beginning in 2000 had a great impact on the direction of research. In 2000, the whole genome sequence of volution , the idevolution . Subsequvolution . AlthougAdvances in plant developmental biology and genetics have relied on a few model plants with well-annotated genome information, genetic resources, and molecular tools. However, the important questions regarding plant development and useful agronomic traits are often associated with morphological characters that are unique to crops. Therefore, it is extremely important to understand the mechanisms of morphological traits that do not exist in model plants and to use them. Recent advances in genome technologies and informatics make molecular approaches more accessible for important non-model crops, which will make it possible to unveil the genetic and molecular mechanisms of morphological traits that are characteristic to individual crops. Furthermore, combined with genome-editing technologies, findings regarding the developmental processes of crops should become even more important for molecular breeding (Breeding Science contains five reviews and one research paper that focuses on recent advances and current challenges in developmental research in crops. These articles cover the developmental biology of rice (Arabidopsis.This special issue of  of rice , sorghum of rice , legumes of rice , and tomWe thank the authors of the articles featured in this special issue for their contributions and thoughtful insights into current advances in this research field. These articles provide valuable information that can be used in future developmental studies and crop breeding. Finally, we would like to thank the Editor-in-Chief, Dr. Tsujimoto, for giving us the opportunity to edit this special issue.


Despite the advances in immunosuppressive medications, antibody-mediated rejection (AMR) continues to be a major cause of kidney allograft failure and remains a barrier to improving long-term allograft survival. Recently, there have been significant advances in the understanding of the pathophysiological process of AMR, along with the development of new therapeutic options. Additionally, surveillance protocols with donor-derived cell-free DNA and gene profile testing have been established, leading to the early detection of AMR. A multitude of clinical trials are ongoing, opening numerous opportunities for improving outcome in kidney transplant recipients. In this brief review, we discuss the emerging therapies for managing both active and chronic active AMR and highlight the ongoing clinical trials. Antibody-mediated rejection (AMR) was first formally described as a clinicopathological diagnosis in the Banff 97classification  and is rThe treatment of AMR has evolved over the past two decades. Due to the many contributing pathways of injury, a multimodal treatment approach is necessary. Current 2009 KDIGO Guidelines , along wIn this review, we searched PubMed and clinicaltrials.gov to collect information about emerging therapies for AMR, both chronic and acute. We added medications that are either in a current clinical trial (regardless of the phase) or with a promising mechanism that would likely end up in a clinical trial in the near future.Carfilzomib is a second-generation irreversible proteasome inhibitor. Its mechanism of action is similar to that of Bortezomib . It has One issue with bortezomib was the rebound injury. A case series involving 23 patients with acute AMR, of whom 11 had refractory AMR, received 1 to 3 cycles of Bortezomib. The study shows an improvement in the serum creatinine (Scr) at the end of therapy (2.4 mg/dL) which was noticed compared with the Scr (2.9 mg/dL) at the beginning of the study, but this improvement was not sustained at follow-up. A lack of histological response was reported in 48% of patients. Based on this result, the authors conclude a poor response of later AMR to both conventional and Bortezomib therapies .In terms of carfilzomib, six nonhuman primate kidney transplant recipients used carfilzomib and belatacept in the desensitizing protocol. It showed a significantly prolonged graft survival and reduced AMR scores on renal biopsy at 1 month. However, four of five animals of long-term graft survival showed the gradual rebound of DSA and AMR .Its effectiveness in humans was studied only in lung and heart transplant recipients who had acute AMR with promising results ,20. But A study of its safety and toxicity showed an acceptable profile as a desensitizing agent . The advOverall, carfilzomib is a promising agent. Future studies are underway, such as clinical trials in organ transplantation (CTOT-42), to evaluate the efficacy of carfilzomib for the treatment of chronic active AMR.Tocilizumab is the first in-class recombinant humanized monoclonal antibody targeted at the interleukin-6 receptor (IL-6R) . It bindPatients treated with tocilizumab are at increased risk of serious infection, including tuberculosis, invasive fungal infections, and bacterial, viral, or other opportunistic infections. Additionally, gastrointestinal perforation and elevation in transaminases have been reported complications .Earlier studies examined the use of tocilizumab in desensitization. A phase I/II trial reported a strategy of using tocilizumab and IVIG as desensitizing agents in sensitized kidney transplant recipients. The study reported this strategy as a safe and effective in reducing the DSA titer and prevention of AMR  Figure .While the available literature is limited for its use in the treatment of acute AMR, Pottebaum et al. evaluated the use of tocilizumab in addition to conventional therapy in seven kidney transplant recipients with acute AMR. Renal function improved or stabilized during the treatment, and a ≥50% reduction in donor-specific antibody (DSA) titers in four patients was noted . HoweverA multitude of studies evaluating tocilizumab in chronic active AMR have been published with promising results. In a study of 36 kidney transplant recipients with chronic active AMR who failed conventional therapy, tocilizumab was offered as a rescue therapy for 6–25 months. Significant reductions in DSA titers and the stabilization of renal function were seen at 2 years in tocilizumab patients, along with graft and patient survival rates of 80% and 91%, respectively, at 6-year follow-up. No significant or severe adverse events were reported . AdditioIn Lavacca et al., tocilizumab adopted as first-line therapy in 15 kidney transplant recipients with chronic active AMR was associated with the stabilization of glomerular filtration rate (GFR) and proteinuria, a significant reduction in DSA titers, and histological improvement on the protocol biopsies after 6 months despite advanced transplant glomerulopathy in most patients at the time of the study’s initiation .On the contrary, conflicting findings have been reported by Kumar et al. who evaluated the efficacy and safety of tocilizumab in 10 kidney transplant recipients with chronic active AMR. The patients received tocilizumab for a median of five doses. No improvements in renal function, change in the slope of eGFR decline, or histological improvement on the protocol biopsies were noted at a median follow up of 12 months. There was one patient death due to a complication from hip infection .Clazakizumab is a genetically engineered, high-affinity, humanized monoclonal IgG1 antibody that binds IL-6. It is the most potent and longest acting in the IL-6/IL-6R blocking category . ClazakiIn a phase 2 single-center open-label study, 10 kidney transplant recipients with refractory active AMR received clazakizumab monotherapy monthly for 12 months. Clazakizumab treatment showed a trend toward the stabilization of eGFR and reductions in DSA titers and graft inflammation . Based oDoberer et al. published a pilot randomized controlled trial evaluating the safety and efficacy of clazakizumab in late AMR. Twenty patients with positive DSA after 1 year of kidney transplant were randomized to receive clazakizumab or placebo weekly for 12 weeks (part A). After a period of 12 weeks, the mean eGFR decline was slower and the DSA titers were significantly decreased in the clazakizumab group. Subsequently, all patients received clazakizumab for 40 weeks (part B). As a result, the slope of eGFR decline improved in those patients. However, 25% of patients developed serious adverse events while on treatment, including diverticulitis, pleural effusions, and acute kidney injury .However, Mayer et al. recently published a secondary endpoint analysis of the effect of clazakizumab treatment on biomarkers indicative of tissue damage (donor-derived cell-free DNA) and parenchymal inflammation (C-X-X motif chemokine ligand) in 20 kidney transplant recipients with late AMR . PatientIn summary, clazakizumab comes with a hope of less rebounding antibodies and rejection than prior IL-6 receptor antibodies.The other IL-6 inhibitors include sitluximab and sirukumab; they are new agents that have not been studied in the context of kidney transplant ,37.Daratumumab is an immunoglobulin G1K human monoclonal antibody. It is the first in-class human-specific therapy to target CD38-expressing plasma cells. CD38-expressing cells also include regulatory T- and B-cells. Daratumumab is an FDA-approved antibody for newly diagnosed or relapsed/refractory multiple myeloma  Figure .Reported adverse events with daratumumab include infusion-related reaction, volume overload, hypogammaglobulinemia, myelosuppression, gastrointestinal upset, and infection .Of note, it is also reported that daratumumab may interfere with cross-matching and red blood cell (RBC) antibody screening as it binds to CD38 on RBCs and results in a positive indirect Coombs test. Another important consideration during daratumumab therapy is the potential for resistance, mainly through complement-inhibitory proteins, CD55 and CD59, and the development of antidrug antibodies .Kwun et al. conducted a study to evaluate Daratumumab therapy as a desensitizing agent in sensitized nonhuman primate model for the management of AMR in two clinical combined heart–kidney transplant recipients. The result of the study showed a significant reduction in DSA titer in the nonhuman primate model and transplant clinical cases when it was used as a desensitizing agent and for the management of AMR. However, the reduction in DSA titer was not maintained in the nonhuman primate as all recipients demonstrated the rapid rebound of antibodies .Multiple case reports over the past 5 years have highlighted promising results of daratumumab use in the treatment of acute AMR. Spica et al. reported a case of its use in refractory AMR in an ABO-incompatible kidney transplant recipient. After failed conventional treatment, the patient received daratumumab as rescue therapy. The blood group antibody titer decreased and remained at low levels and allowed the graft function to recover .Recently, a case report of daratumumab use in two kidney transplant recipients with late or chronic active AMR was published. The patients were treated using a novel regimen of early intensive therapy with daratumumab plus TPE and IVIG and later maintenance therapy with daratumumab alone. A remarkable decrease in DSA titers was noticed. After 20 months of follow-up, both patients maintained low DSA titers and normal/improved renal function while on maintenance. However, one patient deteriorated because of acute T-cell-mediated rejection .Currently there are 304 clinical trials testing daratumumab in diverse pathological conditions, 1 of which includes an evaluation of the efficacy of daratumumab in kidney transplant as a desensitizing agent  Further.Isatuximab is another CD38 inhibitor; it has been approved for use in multiple myeloma . There hBelimumab is a humanized anti-B lymphocyte stimulator (BLyS) IgG1 monoclonal antibody. It is approved by the FDA for the management of systemic lupus erythematosus and has shown therapeutic efficacy in lupus nephritis . BlyS, aGastrointestinal upset, dizziness, infection, depression, and diabetes have been reported adverse events related to belimumab therapy in kidney transplant recipients. Cases of progressive multifocal leukoencephalopathy have also been reported ,50.Belimumab has been studied for the prevention of AMR in a phase 2 randomized controlled trial of 28 kidney transplant recipients randomized to belimumab or matching placebo in addition to standard immunosuppression therapy of basilixmab, mycophenolate, tacrolimus, and prednisone. The study concluded the effectiveness of belimumab with the standard therapy with no increased risk of infection compared to placebo .The CAMPBEL open-label pilot study aimed to evaluate belimumab therapy in addition to the standard immunosuppression therapy of alemtuzumab, and steroid induction with mycophenolate and tacrolimus maintenance in kidney transplant recipient was terminated because of recruitment complications due to the COVID-19 pandemic .Belimumab therapy in kidney transplant recipients with active AMR has not been well studied. In a case report of a combined kidney–pancreas transplant recipient with mixed rejection of the kidney allograft, belimumab was utilized for persistent DSA and inflammation following conventional treatment with TPE, rituximab, and IVIg. The patient was noted to have a reduction in class II DSA and improved graft function ,54.Streptococcus pyogenes which is able to cleave human IgG antibodies at the lower hinge region of the IgG heavy chain. Subsequently, this cleavage leads to the inhibition of complement-dependent cytotoxicity and antibody-dependent cellular cytotoxicity, the cleavage of B-cell receptors, and a reduction in natural killer (NK) cell activity [Imlifidase is a novel recombinant cysteine protease derived from activity  (Figure Imlifidase has primarily been evaluated and is currently being assessed in ongoing studies as part of desensitization protocols . Based oWhile imlifidase remains a promising novel treatment option for the management of AMR, its use may be limited by risk for antibody rebound, including anti-imlifidase antibodies, DSA, and total IgG. Understanding this risk remains insufficient; however, it may potentially be able to be mitigated by the administration of anti-CD20 antibody and/or IVIg. Furthermore, a number of important drug–drug interactions exist. Because imlifidase cleaves IgG antibodies, co-administered antibody-based therapies may also be impacted. Consideration should be given to the appropriate separation of administration with IVIg for 12 h, rituximab, basiliximab, rabbit antithymocyte globulin, and alemtuzumab for 4 days, and belatacept for 1 week to prevent a reduction in the efficacy of concomitant therapies .Numerous studies assessing the efficacy of anti-CD20 monoclonal antibody in the treatment of antibody-mediated diseases have been published. Of the anti-CD20 antibody therapies, rituximab remains a well-established agent utilized in solid organ transplantation and is commonly employed in the current strategy for AMR treatment in kidney transplant recipients.Ofatumumab is an alternative anti-CD20 agent that is approved by the FDA for the treatment of relapsing multiple sclerosis . A case Obinutuzumab is a glyco-engineered type II anti-CD20 monoclonal antibody. When compared to rituximab, a type I anti-CD20 antibody agent and the current standard of care in AMR treatment, obinutuzumab has been shown to offer more profound B-cell depletion  Figure . ObinutuIn the treatment of AMR, obinutuzumab has largely been reserved as an alternative anti-CD20 therapy for refractory cases or in the setting of rituximab intolerance and, to date, the two have not been compared directly. While the literature is limited, cases of AMR non-responsive to rituximab have reported a successful reduction in DSA titers and the stabilization of graft function .Possible adverse events include infections, thrombocytopenia, infusion-related reactions, and cardiac events  (see TabInebilizumab is a CD19 targeting agent. CD19 is expressed in B-cells; inebilizumab targets these B-cells and depletes them. It has been approved in 2020 for use in neuromyelitis . It has Conventional therapies for AMR are still not optimal, with high rates of graft loss leading to poor patient outcomes. Clearly, additional studies to define the optimal treatment of AMR are needed.Newer therapies that target novel pathways in the AMR pathologic process are promising, but randomized studies are vital given the lack of randomized studies with adequate statistical power to compare the safety and efficacy of these novel therapeutics.


HighlightsWidespread use of antibiotics in livestock production contributes to public health concerns.Animal-origin foods could be contaminated with antimicrobial resistance (AMR) bacteria.AMR bacteria and genes have been found in various products of animal origin.Therapeutic expenses have increased in rich countries due to AMR bacteria-caused infections.Dear Editor,It is well accepted that the widespread use of antibiotics in livestock production contributes to the worldwide public health concern known as antimicrobial resistance (AMR). Antibiotics are widely utilized in the cattle business as growth enhancers and as a cheap alternative to good sanitary practices. The intensive use of antibiotics in animal husbandry has been identified as a major contributor to AMR by the United Nations General Assembly The use of antibiotics in intensive animal husbandry and aquaculture practices has a secondary impact on the local ecosystem. AMR genes can proliferate in aquaculture systems that could be exposed to manure runoff from animal agriculture. Eliminating needless antibiotic use in food production could lessen the threat of rising AMR. Countries that export items that do not require using antibiotics could benefit economically and public health-wise if they were given incentives. Examples of such efforts include European regulatory measures aimed at reducing the overuse of antibiotics in animal husbandry, but due to a lack of worldwide surveillance, enforcing such restrictions consistently has proven difficult.Salmonella, often found in contaminated poultry, pork, and beef, has developed into a drug-resistant strain. Poultry act as a major vector for the spread of AMR CampylobacterSalmonellaAnimal-origin foods could be contaminated with AMR bacteria (AMRB). Resistance to antibiotics with essential medicinal uses is being fueled by their unjudged usage in livestock and aquaculture production. In order to fulfill the rising demand for protein, methods for producing meat without antibiotics will be necessary, as global regulation alone is unlikely to be sufficient to control antimicrobial use. One way to separate antibiotics from meat is to produce it in different ways, such as cultured meat (CM) There are three pivotal questions: Could the CM solve part of AMR? Theoretically, cultivated meat could be free from drug residues, resistant bacteria, and food-borne illness pathogens. Compared to the current meat business, the use of antibiotics in the preproduction stage of CM will be extremely low, in addition to the tendency of CM producers to eliminate antibiotic usage in their processes Salmonella and Escherichia coli are found in the gut and can contaminate the food supply and cause food poisoning if they are excreted. These will not be present in a cultivated meat production facility.Therapeutic expenses have increased in rich countries due to AMRB-caused infections, but the increased rates of related morbidity and death are shown mainly in developing countries. Given that CM is made in a laboratory, it is protected from any potential contamination that may occur during the slaughter of animals. Traditional animal products are a major contributor to the epidemic, food-borne disease, and food recalls; hence, CM is promoted as safer. Antimicrobial resistance is currently the largest cause of death worldwide, contributing to an estimated 4.95 million deaths annually. It is predicted that there will be 10 million AMR-related deaths annually by 2050. By 2050, the global population is expected to surpass 9.5 billion, with the expected increased demand for meat to be 73%. So, we must design a food system for the future that will simultaneously protect the planet’s natural resources and biodiversity while also providing people with access to cheap, nutritious food. This situation calls for a long-term solution, and CM could provide that, by guaranteeing contaminants-free procedures during the stages of manufacturing of CM and animal-component-free commercial production.Not applicable.None.A.A.S.: conceptualization, data curation, writing – original draft preparation, writing – reviewing and editing. D.C., H.C., A.D., and K.D.: data curation, writing – original draft preparation, writing – reviewing and editing. T.B.E.: writing – reviewing and editing, visualization, supervision.Authors declare that they have no conflicts of interest.NoneTalha Bin Emran, PhD, Associate Professor, Department of Pharmacy, BGC Trust University Bangladesh, Chittagong 4381, Bangladesh. Tel: +880 303 356 193, Fax: +880 312 550 224. https://orcid.org/0000-0003-3188-2272.The data in this correspondence article is not sensitive in nature and is accessible in the public domain. The data is therefore available and not of a confidential nature.Not commissioned, internally peer-reviewed.


Clear cell endometrial carcinoma (CCEC) represents a relatively rare and heterogeneous entity. Based on The Cancer Genome Atlas (TCGA) molecular classification, the risk stratification and management of endometrial cancer (EC) have been improved. Although the relationship of CCEC with the TCGA classification is less well understood, data has emerged to suggest that molecular classification plays an important role in the prognosis and management of CCEC. Most of patients with CCEC are characterized by p53abn or NSMP type and the prognosis of these patients is poor, whereas those with MMRd or POLEmut seem to have a favorable prognosis. Adjuvant therapy is recommended in CCEC with p53abn and NSMP. Advanced/recurrent CCEC with MMRd benefit much more from immune checkpoint inhibitors after the failure of platinum-based chemotherapy. In addition, bevacizumab plus chemotherapy upfront seems to improve outcomes of advanced/recurrent patients whose tumors harbored mutated TP53, including CCECs with p53abn. Further studies which exclusively recruit CCEC are urgently needed to better understand the role of molecular classification in CCEC. This review will provide an overview of our current understanding of TCGA classification in CCEC. Owing tTraditionally, based on biological and clinical parameters, endometrioid endometrial cancer is considered as “type I” EC and accounts for 80% of EC, whereas non-endometrioid (i.e. serous and clear cell) histology tumors has been regarded as “type II” EC since it is not estrogen-related and has poor prognosis –5. Howev2Since TCGA classification of EC was proposed, several groups have described the molecular classification of CCEC. CCEC was found within all four molecular subtypes and encompassed a wide range of clinical outcomes , 10, 11.2.1According to the NCCN guidelines, CCEC is considered a high-risk histologic type of EC and requires adjuvant therapy in most case. Even in early-stage CCEC, the risk of recurrence is still high and adjuvant chemotherapy mitigates the risk of distant metastases , howeverPORTEC-3 trial explored the benefit of combined adjuvant chemotherapy and EBRT(CTRT) versus EBRT alone in patients with high-risk EC (including CCEC) , 21. HowIt needs to be emphasized that patients with mixed endometrioid and clear cell carcinoma are characterized by MMRd . SimilarSignificantly, the integration of molecular signature and clinicopathological factors would provide a more tailored management for ECs –27. An i2.22 every 21 days for six cycles should be considered the first-line therapy for recurrent or metastatic EC  with standard chemotherapy for high risk or recurrent EC, showed no PFS benefit compared with historical controls, namely the carboplatin-paclitaxel arm of trial GOG209 , 41. RecFurthermore, since HER-2 overexpression has been described in the p53abn CCEC, it is possible that the subgroup may be sensitive to anti-HER-2 targeted therapy , 44. AddOf note, no data are available specifically for CCEC, either on immune checkpoint inhibitors or on targeted therapy. Successfully combining targeted agents and immunotherapy with molecular classification is an important future goal for recurrent/advanced CCEC therapy.3Herein, we summarize the role of molecular classification in the management and prognosis of clear cell endometrial cancer (CCEC) which represents an uncommon disease entity, with different characteristics from endometrioid and other non-endometrioid cancers. Theoretically, adjuvant therapy could be omitted in patients with stage I/II CCEC harboring POLE mutation, whereas adjuvant therapy is recommended in patients with NSMP and p53abn CCEC. With respect to MMRd CCEC, recommendations for adjuvant therapy are unclear. Immunotherapy seems to be the more promising treatment option for patients with advanced or recurrent CCEC characterized by MMRd. In terms of prognosis, CCECs with p53abn and NSMP account for a large majority of all CCECs and have poor clinical outcomes, while those with MMRd or POLEmut have very favorable outcomes. Clinical outcomes of CCEC are different from what has been reported previously, where review of EC in which molecular subtype classification had been applied revealed that POLE-mutated EC has a favorable prognosis, p53abn EC has a poor prognosis, and MMRd and NSMP EC have the intermediate prognosis. Thus, NSMP CCEC appear to be a distinct clinicopathological entity within the larger group of NSMP ECs. Moreover, the integration of molecular signature with pathological factors and genomic profiling would ensure a more tailored management of patients in accordance with the principles of the precision medicine. To date, the number of patients with CCEC is relatively small and few studies have focused exclusively on CCEC in the context of the TCGA classification, therefore, further studies that focus specially on CCEC are necessary, and future clinical trials which include molecular classification subgroups and specific targeted treatments in their design are also needed.YH conceived the project. All authors reviewed the literature and drafted the article. YH revised the manuscript. All authors contributed to the article and approved the submitted version.