To evaluate the feasibility of adoptive cell therapy (ACT) using ex vivo‐expanded tumor‐infiltrating lymphocytes (TILs) in Japanese patients with melanoma who failed immune‐checkpoint inhibitor therapy, an open‐label, single‐arm, pilot study was conducted.,We investigated the immunological and genetic factors of the pretreatment tumor and expanded TILs that may be associated with the clinical response.,The treatment protocol comprised preparation of TIL culture, lympho‐depleting non‐myeloablative preconditioning with cyclophosphamide and fludarabine, TIL infusion, and intravenous administration of low‐dose IL‐2.,Three patients of clinical subtypes mucosal, superficial spreading, and acral melanoma underwent TIL‐ACT.,Most severe adverse events, including fever and leukopenia, were manageable with the supportive regimen specified in the protocol, suggesting that the TIL‐ACT regimen is suitable for Japanese patients with melanoma.,One patient showed a short‐term partial response, one relatively long‐stable disease, and one experienced disease progression.,Whole‐exome and transcriptional sequencing of isolated tumor cells and immunohistochemical analyses before TIL‐ACT revealed various immunostimulatory factors, including a high tumor mutation burden and immune cell‐recruiting chemokines, as well as various immunosuppressive factors including TGF‐β, VEGF, Wnt/β‐catenin, and MAPK signaling and epithelial‐to‐mesenchymal transition, which might influence the efficacy of TIL‐ACT.,Our results imply mechanisms for the antitumor effect of and resistance to TIL‐ACT.,Further studies of immune‐resistant mechanisms of TIL‐ACT are warranted.,This study is registered with the UMIN Clinical Trial Registry (UMIN 000011431).,Various factors involved in the balance of immunostimulation and immunosuppression are important in the TIL‐ACT response for melanoma patients.
Melanoma aggressiveness determines its growth and metastatic potential.,This study aimed at identifying new molecular pathways controlling melanoma cell malignancy.,Ten metastatic melanoma cell lines were characterized by their proliferation, migration and invasion capabilities.,The most representative cells were also characterized by spheroid formation assay, gene- and protein- expression profiling as well as cytokines secretion and the most relevant pathways identified through bioinformatic analysis were tested by in silico transcriptomic validation on datasets generated from biopsies specimens of melanoma patients.,Further, matrix metalloproteases (MMPs) activity was tested by zymography assays and TNF-alpha role was validated by anti-TNF cell-treatment.,An aggressiveness score (here named Melanoma AGgressiveness Score: MAGS) was calculated by measuring proliferation, migration, invasion and cell-doubling time in10human melanoma cell lines which were clustered in two distinct groups, according to the corresponding MAGS.,SK-MEL-28 and A375 cell lines were selected as representative models for the less and the most aggressive phenotype, respectively.,Gene-expression and protein expression data were collected for SK-MEL-28 and A375 cells by Illumina-, multiplex x-MAP-and mass-spectrometry technology.,The collected data were subjected to an integrated Ingenuity Pathway Analysis, which highlighted that cytokine/chemokine secretion, as well as Cell-To-Cell Signaling and Interaction functions as well as matrix metalloproteases activity were significantly different in these two cell types.,The key role of these pathways was then confirmed by functional validation.,TNF role was confirmed by exposing cells to the anti-TNF Infliximab antibody.,Upon such treatment melanoma cells aggressiveness was strongly reduced.,Metalloproteases activity was assayed, and their role was confirmed by comparing transcriptomic data from cutaneous melanoma patients (n = 45) and benign nevi (n = 18).,Inflammatory signals such as TNF and MMP-2 activity are key intrinsic players to determine melanoma cells aggressiveness suggesting new venue sin the identification of novel molecular targets with potential therapeutic relevance.,The online version of this article (10.1186/s13046-018-0982-1) contains supplementary material, which is available to authorized users.