Vascular complications, such as HAT, are an important cause of graft loss and recipient mortality. We aimed to characterize post-transplant thrombotic events in a cohort of liver transplant recipients, and identify independent risk factors for these complications.We conducted a thrombophilic study of 293 orthotopic liver transplants performed in the Digestive Surgery Department of the 12 de Octubre Hospital  between January 2001 and December 2006.The most frequent post-transplant thrombotic events were HAT (9%) and PVT (1.7%). The one variable associated with post-transplant thrombotic event was a high fibrinogen level in the global cohort of liver transplantation. But toxicity as event post-OLT has been associated with post-transplant thrombotic event in the retrospective group and high fibrinogen level and low protein C levels were associated post-transplant thrombotic event in the prospective group. Liver disease relapse , high levels of FVIII ) and low levels of antithrombin  were associated with poor overall survival (OS).In conclusion, high fibrinogen and decreased protein C levels were associated with allograft thrombosis. Further studies are required in order to assess the clinical relevance of these parameters in prospective studies and to study the effect of anticoagulation prophylaxis in this group of risk. Vascular complications after orthotopic liver transplantation (OLT) are one of the most feared problems that frequently result in graft and patient loss. Early hepatic artery thrombosis (eHAT) is a major complication following liver transplantation and since Starzl's first report on human liver transplantation it is recognized as an important cause of graft loss and mortality ,2.HAT is generally believed to result primarily from surgical techniques . However, some studies show that eHAT is also associated with no-surgical factors, such as donor age , rejectiRecently a meta-analysis of the incidence, risk factors and outcome of eHAT after liver transplantation showed the risk factors of eHAT to be cytomegalovirus (CMV) mis-match, re-transplantation, arterial conduits, prolonged operation time, low recipient weight, variant arterial anatomy, and low volume transplant centers . HoweverWe aimed to characterize post-transplant thrombotic events in a cohort of liver transplant recipients, and to identify possible parameters that could lead to HAT and could be responsible for graft loss due to thrombosis in extended thrombophilia study.Between January 2001 and December 2006, 441 orthotopic liver transplants (OLT) were performed in the Digestive Surgery Department of the 12 de Octubre Hospital . There were 441 grafts and 437 liver recipients. Before initiating this study, 74 recipients had died . In another 74 cases, we were unable to obtain laboratory results because the referred patients did not attend follow-up visits at our study center, or did not sign the consent form. Wherever possible all patients are lab tested for hypercoagulation study irrespective of any presence of thrombophilia.We have therefore reported analytical thrombophilia results for 293 patients. As this study was initiated in July 2004, the majority of patients had already undergone OLT. Thus, blood samples for these patients could only be taken at their post-transplant follow-up visits. The present work is made up of a retrospective study that includes 167 patients up to July 2004 and a later prospective study that includes another 126 patients. Blood samples were taken at a median of 26.3 months and 3.1 months post-transplantation in the retrospective and prospective studies, respectively. Patients of the retrospective group were evaluated by medical reports. From 2004, the evaluation was prospective for all patients, monthly of quarterly. Clinical and analytical studies were utilized for evaluation of patients. Abdominal Doppler, computed tomography scan, or hepatic biopsies were carried out whenever necessary. The analysis has been done separately in both the prospective and retrospective groups. The study was approved by our Ethical Institutional Review Board and all patients gave their consent for blood samples to be further processed. Data on thrombophilia risk factors were collected by personal interview, or by reviewing the medical history.The study population comprised 293 males and 144 females ranging from 1 month to 74.5 years old (median 51.73 y). Two-hundred and eighty-six cases were primary OLTs, 46 were secondary OLTs, and 9 cases were tertiary OLTs. The cause of liver transplantation was: 20 HBV (hepatitis B virus), 57 HCV (hepatitis C virus), 40 HBV and HCV, 53 Ethanol, 8 Autoimmune, 7 Toxicity, 68 Tumor, 16 Alpha 1 antitrypsin deficits, 14 Biliary atresia. We use "toxicity" to mean liver damage probably caused by immunosuppressant therapy diagnosed by liver biopsy. Three patients have received anticoagulation therapy pre-OLT and 11 patients anticoagulation therapy post-OLT. These patients were considered separately. Post-OLT immunosuppressant regimen was triple therapy: FQ (tacrolimus) or CsA (cyclosporine), MMF (mycophenolate mofetil) and Cc (corticosteroids). Corticosteroid is administred for 1 month post-OLT (1mg/kg/day), and is later reduced to zero.Forty-one live donor liver transplantation (LDLT), and 252 deceased donor liver transplantation (DDLT) donors were evaluated. Eighty-six partial graft livers were employed in the cases of DDLT. LDLT donors comprised 24 males and 17 females with a median age of 32 y . LDLT donors were assessed before OLT using functional coagulation and genetic tests. In DDLT donors, only genetic tests were carried out. Genetic studies were performed in 293 recipients and 222 donors . Seventy one donor samples were not suitable.The extracted genomic DNA was processed to detect Factor V Leiden, prothrombin G20210A and methylenetetrahydrofolate (MTHFR) C667T mutations, using real-time PCR (polymerase chain reaction) with hybridization probes in a light-cycler . We have tested these genetic mutations in a subgroup of donors and recipients appropriately matched and the tests were performed in the donors on blood samples collected at the time of procurement.APhL® ELISA Kit . Platelet counts were done on the ADVIA 2120 . Factor VIII was measured by one-stage clotting assays  and was said to be increased at levels above 150 IU/dL.The following panel of tests was run: prothrombin activity (PA)  , activated partial thromboplastin time (APTT) , and thrombin clotting time (TT) . Fibrinogen concentration was measured with a coagulometric assay using the Clauss method . AT , PC , and PS  activities were measured using chromogenic substrate assays. PS antigen levels were assessed by enzyme linked immunosorbent assay (ELISA) . Levels of homocysteine were measured by fluorescent polarization immunoassay (FPIA) using the Abbott Laboratories IMX System . Hyperhomocysteinemia was defined as a homocysteine level > 14 μmol/L. Activated PC resistance (APCR) was measured by Coatest APC resistance , and IgG and IgM anti-cardiolipin antibodies were measured using the Data on the clinical evolution of recipients were collected by searching their medical records. Deep vein thrombosis (DVT), organ vein thrombosis , pulmonary embolism (PE), myocardial infarction, ischemic stroke, and peripheral arterial disease, were defined as a pre-transplant thrombosis when the event occurred before liver transplantation, and were defined as post-transplant thrombosis when the event occurred after liver transplantation. Thrombotic events were diagnosed by Doppler ultrasonography, computed tomography scan, or hepatic biopsies. The follow-up period for donors and recipients began on the date of liver transplantation, and ended on the date of death, date of re-transplant, or the end of study . Follow-up periods ranged from 15 d to 8 y (median: 27 months).The Pearson's chi-square (χ2) statistic (or Fisher's exact test) and the Student's t test  were used to test for differences in the distribution of dichotomous variables, and for differences in the mean values of continuous distributions. Forward stepwise logistic regression was used to identify independent risk factors for PVT and HAT. The following variables collected at diagnosis were included in the database: gender , age , the existence of clinical thrombophilia risk factors, the original liver disease, and post-transplantation events.P value less than 0.05 were considered significant.Overall survival (OS) was calculated from the day of the liver transplantation to death. Kaplan-Meier life tables were constructed for survival data and were compared by means of the log-rank test. A census of the surviving patients was taken on March 1, 2007. The median follow-up time was 21.7 months (range 1-184.6 months). Results with a In recipients, the prevalence of the heterozygote Factor V Leiden mutation was 7 of 293 (2.4%), the heterozygote G20210A prothrombin mutation was 13 (4.5%), and the homozygote C677T MTHFR mutation was 41 (14.1%). In donors, the prevalence of the heterozygote Factor V Leiden mutation was 4 out of 222 (1.6%), the heterozygote G20210A prothrombin mutation was 7 (2.8%), and the homozygote C677T MTHFR mutation was 33 (13%). Pathology results in this population showed the following: 32 cases (10.9%) had PA < 80%; 34 (11.6%) had a prolonged APTT (> 36”) and 7 (2.4%) had a reduced APTT (< 26”); 19 cases (6.5%) had fibrinogen > 400 mg/dL, and 6 (2%) had fibrinogen < 150 mg/dL; 21 cases (7.2%) had AT < 80%; 143 (48.8%) had FVIII > 150%, and one (0.34%) had FVIII < 65%; 30 (10.2%) had PC < 65%; 53 (18.1%) had PS < 65%; 70 (23.9%) had plasma homocysteine >14 µmol/L. Anti-cardiolipin IgG or IgM was high in 25 cases (8.5%) , and 4 (1.4%) were APC-resistant after OLT (≤ 2). 7 factor V Leiden carrier recipients received a no-Leiden liver and all factor V Leiden carrier recipients were not APC-resistant after transplantation  as expected. Nevertheless neither of the 2 recipients analyzed with a factor V Leiden graft were APC-resistant after the transplant (2.91 and 2.24). Three of four no-Leiden carrier recipients who were APC-resistant after OLT showed higher FVIII levels , but only one donor could be tested, and that donor was found to have a wild-type FV genotype. The Coatest assay used not include factor V deficient plasma, then the APC-resistance can be caused by high factor VIII. Recipients.- Fifty-eight (12.8%) patients developed a post-transplant thrombotic event .Living donors.- After surgery, donors' liver function recovered well and no bleeding events were recorded. Donors did not experience thrombotic events, neither during the immediate post-transplant nor during the follow-up periods [ periods .P < 0.001). The patients with biliary atresia, all children, showed a higher frequency of post-transplant thrombotic event . The presence of toxicity was associated with post-transplant thrombotic event  but not the presence of tumours. , and the second most frequent was PVT (8/441 cases), and one with HAT and PVT. Of all 50 graft thrombosis cases, 38 were secondary liver transplantations. HAT and PVT were most frequent when the recipient was a child  in the post-transplant period, the thrombophilic factors were: case 1, complicated post-surgery period ; case 2, smoking and previous surgery; case 3, diabetes and tumour associated; cases 4 and 5, relapse HBV or HCV and tumour associated; case 6, with previous pregnancy complications, she developed acute lymphoblastic leukemia and a DVT with slightly low antithrombin. As expected, an increased frequency of subjects with associated cancer was found among patients with no-liver related post-transplant thrombotic event.P < 0.001) and fibrinogen levels (P < 0.001) were associated with post-transplant thrombotic event in univariate analysis.The laboratory findings of the two groups with or without post-transplant thrombotic event are reported in Table Live donor candidates were excluded from donation if they presented any abnormalities in the hemostatic study, due to genetic mutations, anticoagulant protein deficiencies, factor VIII deficiency or high levels of anticardiolipin antibodies .Lower recipient platelets count and fibrinogen, AT, PC, PS were associated with liver disease relapse but not the FVIII level. , hemodynamic problems during surgery (4 cases), infections (4 cases), haemolytic anemia (2 cases), previous venoocclusive disease (3 cases), and no-heart-beating donor (2 cases). Frequent characteristics of the late HAT group were cirrhosis due to HCV reactivation (10 cases), graft rejection (6 cases), severe infections (3 cases), and hepatocellular tumour (6 cases).p = 0.006). Other events such as toxicity, showed a tendency to be associated with late HAT (p = 0.064). Other clinical and laboratory variables were not especially associated with early or late HAT.Considering only the population with post-transplant thrombosis, partial graft resection was associated with early HAT . Certain post-transplant events were associated with late HAT, such as tumor , cirrhosis recurrence , and also low PC , in the global cohort of liver transplantation (Table In the multivariate study the one variable associated with post-transplant thrombotic event was a high fibrinogen level (continuous variable) . Figure To determine whether the presence of post-transplant thrombotic event influenced recipient survival, we performed a survival analysis Figure . The resPost-transplant HAT and/or PVT increase the potential for graft loss. The frequency of post-transplant HAT has been previously recorded as 4.5% to 6%,15. In oLiver transplantation itself also changes the dynamics of coagulation, with a pro-coagulant pattern in the first weeks post-transplant. Due to the thrombophilia study was carried out between 1.2 months to 4.1 months post-transplant, thrombophilic abnormalities in immediate post-surgery, with influence in the development of early HAT, could be underestimated. Nevertheless, we detected thrombophilic abnormalities that were still evident during the first 3 months post-surgery or during the late post-transplant period, and which were associated with HAT.The importance of genetic thrombophilia risk factors in PVT has been investigated in several studies -19 but aMost of the coagulation changes due to genetic mutations in the recipient are corrected by liver transplantation. Of the 293 patients screened for genetic analysis of Factor V Leiden and who underwent functional studies of APCR after OLT, 7 heterozygous carriers of Factor V Leiden displayed a loss of APCR after transplantation, as previously described -22. In oSome of the variables associated with post-transplant thrombotic event could relate to difficulties in surgical technique, such as in a child recipient, and also their primary cause of liver transplantation, biliary atresia. In a recent study , post-trOur results were in agreement with previous studies  showing To the best of our knowledge, this is the first extensive thrombophilia study in a large cohort of liver recipients. Therefore, our study does not support universal long thrombophilia screening in liver recipients. High fibrinogen and decreased protein C are associated with allograft thrombosis. The practical impact these findings could be the need to include parameters such as fibrinogen and protein C levels as risk factors of graft thrombosis and to assess the effect of anticoagulation prophylaxis in this group of risk. Further studies are required in order to assess the clinical relevance of these parameters in prospective studies.The authors declare that they have no competing interests.Contribution: RA, JML and CR designed research; RA and RB performed molecular and functional experiments; RA, JML, TC, RB, CJ, EM, and CR analyzed and interpreted data; RA designed, performed, and wrote the manuscript; JML and CR supervised the research and critically revised the manuscript. All authors read and approved the final manuscript.The pre-publication history for this paper can be accessed here:http://www.biomedcentral.com/1471-230X/11/130/prepubTable S1. Clinical thrombophilic risk factors in association with post-transplant thromboses.Click here for fileTable S2. Mean Comparison (T Student Test) of study variables in function of recidive as event post-transplant.Click here for file


Xeroderma pigmentosum complementation group C gene (XPC) is a key member of nucleotide excision repair pathway and plays an important role in human DNA repair system. It is reported that several common polymorphisms of XPC are associated with susceptibility to lung cancer. However, the conclusion is still elusive.This meta-analysis was performed to determine the relationship between XPC polymorphisms  and lung cancer risk. Published literatures were identified by searching online databases and reference lists of relevant studies. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated to estimate the association strength. Publication bias were detected by Egger’s and Begg’s test.After strict screening, we identified 14 eligible studies in this meta-analysis, including 5647 lung cancer cases and 6908 controls. By pooling all eligible studies, we found that the homozygote Gln939Gln genotype was associated with a significantly increased risk of lung cancer in Asian population . As for the PAT polymorphism, in Caucasian population, we found carriers of the −/− genotype were associated significantly reduced risk of lung cancer in homozygote comparison model .In this meta-analysis we found that Gln939Gln genotype was associated with significantly increased risk of lung cancer in Asian population; the PAT −/− genotype significantly reduced susceptibility to lung cancer in Caucasian population; while the XPC Ala499Val polymorphism was not associated with lung cancer risk. Lung cancer is the leading cause of cancer-related death worldwide. In 2008, 1.61 million new cases of lung cancer were diagnosed, accounting for 12.7% of all new cases of malignant tumors A lot risk factors, such as tobacco smoking, ultraviolet, and ionizing radiation, can cause the formation of bulky adducts, crosslinks, and strand breaks in DNA This meta-analysis was performed and reported according to the PRISMA guideline . A literStudies were selected according to the following inclusion criteria: (1) full-text published articles; (2) epidemiological association studies with a hospital-based or population-based design; (3) investigating the association between XPC polymorphisms  and lung cancer risk; (4) providing detail genotype frequencies for calculating pooled odds ratio. The exclusion criteria were as follows: (1) studies without detail genotype frequencies, which were unable to calculate odds ratio; (2) if there were multiple reports of the same study, only the one with most participants or the most recent one was included and the others were excluded. Titles and abstracts of searching results were screened and full text papers were further evaluated to confirm eligibility. Two reviewers (Bo Jin and Yu Dong) independently selected eligible studies. Disagreement between the two reviewers was settled by discussing with the third reviewer (Baohui Han).The following data was collected by two reviewers (Bo Jin and Yu Dong) independently using a pre-designed form: name of first author, publishing time, country where the study was conducted, genotyping methods, ethnicity, source of control, number of cases and controls, genotype frequency in cases and controls. Studies with a sample size of more than 500 participants were defined as “large”; otherwise “small”. Different ethnicity descents were categorized as Asian and Caucasian. Eligible studies were defined as hospital-based (HB) and community-based (PB) according to the source of control.The association strength between XPC polymorphisms  and cancer risks was measured by odds ratio (OR) with 95% confidence intervals (95% CI). The estimates of pooled ORs were achieved by calculating a weighted average of OR from each study. A 95% CI was used for statistical significance test and a 95% CI without 1 for OR indicating a significant increased or reduced cancer risk. Odds ratios of 5 comparison models were calculated: homozygote (AA vs. aa), heterozygote (Aa vs. aa), dominant (AAAa vs. aa), recessive (AA vs. Aaaa), and allele (A vs. a) comparison models . subgroup analyses were performed according to (i) source of control, (ii) ethnicities, and (iii) sample size, to examine the impact of these factors on the association. To test the robustness of association and characterize possible sources of statistical heterogeneity, sensitivity analysis were carried out by excluding studies one-by-one and analyzing the homogeneity and effect size for all of rest studies.2 test (P<0.05 means deviated from HWE). All analyses were performed using Stata version 11.0 .Chi-square based Q test was used to check the statistical heterogeneity between studies, and the heterogeneity was considered significant when p<0.10 By searching online databases and references and related papers, 219 records were retrieved. After the primary screening of titles and abstracts, 14 full-text articles were identified The Lys939Gln polymorphism was investigated in 10 studies 4030 lung cancer cases and 5336 controls were available for the analysis of XPC Lys939Gln polymorphism and the meta-analysis results were showed in 2605 patients and 3329 controls contributed to the analysis of XPC Ala499Val polymorphism. By pooling all eligible studies, we did not find any significant association between XPC Ala499Val polymorphism and susceptibility to lung cancer Click here for additional data file.Figure S2Funnel plot of XPC Ala499Val polymorphism. Circles represent the weight of each study.(TIF)Click here for additional data file.Figure S3Funnel plot of XPC PAT polymorphism. Circles represent the weight of each study.(TIF)Click here for additional data file.Checklist S1PRISMA Checklist.(DOC)Click here for additional data file.


TP53 gene is one of the most important tumor suppressor genes. We undertook this meta-analysis to explore the association between TP53 Arg72Pro polymorphism and the risk of skin cancer mainly in Caucasians.We searched PubMed for case-control studies published up to March 2013. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the strength of association.TP53 Arg72Pro polymorphism and skin cancer was observed in all genetic contrast models . Similar results were obtained in the stratified analysis by ethnicity and histological types of skin cancer, such as melanoma, squamous cell carcinoma and basal cell carcinoma. Power calculations indicated that some studies were underpowered. No publication bias was found by using the funnel plot and Egger's test.A total of 5276 skin cancer cases and 5315 controls from 20 studies were included. Overall, no significant association between TP53 Arg72Pro polymorphism probably had little association with skin cancer susceptibility mainly in Caucasians. However, larger sample-size studies are required to verify the conclusion as low statistical powers.This meta-analysis indicated that  According to epidemiology, skin cancer including melanoma and non-melanoma is the most common type of cancer in white populations . StatistTP53 gene is a tumor suppressor gene which can regulate cell cycle arrest, cell apoptosis and DNA repair [TP53 gene are the most common genetic abnormality found in many kinds of human cancers, such as lung cancer, colon cancer, gastric cancer, skin cancer, et al [TP53 gene is a G-C transversion at codon 72, resulting in an amino acid change from arginine (Arg) to proline (Pro) [TP53 gene plays an important role in the cellular genome protection from UV exposure [A repair . Hence, r, et al . Arg72Prne (Pro) . Studiesexposure ,12. But TP53 Arg72Pro polymorphism and the risk of skin cancer, but their results remain inconclusive. Thus, we performed this meta-analysis of all eligible case–control studies that have been published to help us for a better understanding of the influence of TP53 Arg72Pro polymorphism.Many studies in recent years have investigated the association between We searched PubMed for publications up to March 2013, using the terms “TP53,” “polymorphism,” and “skin cancer.” The search was performed without any restrictions on language. Besides, we searched the reference lists of reviews and retrieved articles manually. When the same patient population appeared in several articles, we chose the largest sample size or the most recent one.TP53 Arg72Pro polymorphism and the risk of skin cancer; (2) skin cancer was diagnosed by pathology; (3) containing useful genotype frequencies; and (4) the distribution of genotypes among controls were in Hardy-Weinberg equilibrium.The selected studies must have met the following major criteria: (1) well-designed case-control studies to evaluate The exclusion criteria included: (1) the genotype frequencies or number not presented; (2) animal studies, reviews, case reports, abstracts and family-based studies; (3) duplication of a previous publication.Two investigators extracted information from eligible studies independently, according to the inclusion and exclusion criteria above. Disagreements were resolved by discussion or a third investigator. The following information was collected: first authors, publication year, ethnicity, characteristics of cases and controls , histological type of cases, genotyping method, number of genotypes and total number of cases and controls. In the paper of Rizzato et al the non coding strand has been genotyped, so we inverted the genotypes in his paper.TP53 Arg72Pro polymorphism and the risk of skin cancer was evaluated by pooled odds ratios (ORs) with 95% confidence intervals (CIs). The pooled ORs for dominant model (Arg/Arg + Pro/Arg versus Pro/Pro), recessive model (Arg/Arg versus Arg/Pro + Pro/Pro), codominant model (Arg/Arg versus Pro/Pro and Arg/Pro versus Pro/Pro) and the allele contrast  were calculated, respectively. Stratified analyses were performed by ethnicity and histological type of skin cancer. The heterogeneity assumption was assessed by the Chi-square-based Q-test. If P<0.05 of the Q-test which indicated heterogeneity, the random-effects model was used to calculate the pooled ORs. Otherwise, the fixed-effects model was adopted. The Z test was applied to determine the pooled OR with the significance set at P<0.05. Potential publication bias was estimated by Begg’s funnel plot [http://biostat.mc.vanderbilt.edu/wiki/Main/PowerSampleSize) [The strength of the association between nel plot  and Eggenel plot . P>0.05 pleSize) .A total of 165 papers were obtained by the publication search published until March 2013, among which twenty met the inclusion criteria  Figure . The ultMost of the studies 16 of 20) were conducted in Caucasians. Of the twenty case-control studies, four only focused on melanoma ,29-31, f were conAs shown in TP53 gene and the risk of melanoma, SCC and BCC. Similar results were found in the stratified analysis by ethnicity. Different from other subgroups, power calculations on the SCC gene models were all more than 80%, which revealed adequate sample sizes , which indicated no publication bias. TP53 tumor suppressor gene plays an important role in the cell cycle arrest and activation of programmed cell death [TP53 gene have been detected in 50% of all human cancers and in almost all skin carcinomas [TP53 gene involves in the induction of skin cancer by UV radiation [TP53 gene locates at codon 72, which is a G-C transversion, causing an amino acid change from arginine (Arg) to proline (Pro) [TP53 gene are different. According to the study conducted by Dumont et al, the Arg72 variant induces cell apoptosis markedly better than the Pro72 variant does [TP53 Arg72Pro polymorphism and the susceptibility of skin cancer, but their conclusions are contradictory. Hence, we performed this meta-analysis to further investigate the influence of TP53 Arg72Pro polymorphism on the development of skin cancer.ll death ,36. Mutarcinomas . Studiesadiation ,12,38. Tne (Pro) . The funant does . RecentlTP53 Arg72Pro polymorphism and the risk of skin cancer in any genetic model . In the stratified analysis by ethnicity and histological types of skin cancer, there was no evidence of a significant association, neither. Our results were similar to the meta-analysis conducted by Jiang in 2011 [The results suggested that no significant association between  in 2011 .However, the results of our meta-analysis should be interpreted with caution. Except SCC subgroup, most of the power calculations on the pooled frequencies were lower than 80%, which demonstrated inadequate sample sizes.This meta-analysis also had some limitations. First, given that only twenty studies were included, publication bias could potentially exit, even though we tried to find as many studies as we could, carefully assessed the literature and used statistical methods to minimize the publication bias, and no statistically significant publication bias was observed in this meta-analysis. Second, in the stratified analyses by ethnicity, most studies were conducted in Caucasians, and information about other ethnicities, such as African, was insufficient. Thus, more studies with larger sample size and high quality, especially for non-Caucasian populations are needed to demonstrate our conclusions in the future. Finally, the case-control study belongs to retrospective research that has methodological deficiencies.TP53 Arg72Pro polymorphism probably had little association with the risk of skin cancer mainly in Caucasians. Nevertheless, it is still necessary to conduct larger size and better- designed studies to explore TP53 Arg72Pro polymorphism as low statistical powers.Despite of limitations, this meta-analysis indicated that Figure S1Flow chart of the literature.(DOC)Click here for additional data file.Checklist S1PRISMA checklist.(DOC)Click here for additional data file.


P < .01). Since lipoprotein lipase hydrolyzes triglyceride in the VLDL-LDL cascade, we examined whether these two patterns of lipoprotein diameter were associated with differences across two lipoprotein lipase (LPL) gene variants: D9N (rs1801177) and S447X (rs328).Previous analysis clustered 1,238 individuals from the general population Genetics of Lipid Lowering Drugs Network (GOLDN) study by the size of their fasting very low-density, low-density and high-density lipoproteins  using latent class analysis. From two of the eight identified groups (N = 251), ~75% of individuals met Adult Treatment Panel III criteria for the metabolic syndrome (MetS). Both showed small LDL diameter (mean = 19.9 nm); however, group 1 (N = 200) had medium VLDL diameter (mean = 53.1 nm) while group 2 had very large VLDL diameter (mean = 65.74 nm). Group 2 additionally showed significantly more insulin resistance (IR), and accompanying higher waist circumference and fasting glucose and triglycerides . However, group 2 contained significantly more carriers (25%) of the 447X variant than group 1 .Mixed linear models that controlled for age, sex, center of data collection, and family pedigree revealed no differences between the two groups for the D9N polymorphism (LPL and large VLDL particle size within the MetS, a pattern associated with higher IR. Future work should extend this to larger samples to confirm these findings, and examine the long term outcomes of those with this lipoprotein diameter pattern.This was the first study this kind to show an association between  The MetS is characterized by three or more of the following features: increased waist circumference (WC), high triglycerides (TGs), lowered high density cholesterol (HDL-C), hypertension and impaired fasting glucose . Shifts Our previous research grouped individuals according to the fasting diameters of their VLDL, LDL and HDL particles. Two groups emerged where individuals, on average, met the adult treatment panel (ATP) III criteria for the MetS. Both groups had small LDL diameters mean = 19.9 nm), but one group with larger VLDL diameters (65.74 vs 53.1 nm) showed higher IR as measured by homeostatic model assessment . The LCA was implemented using the TRAJ Procedure in SAS [Latent class analysis (LCA) was used to group all GOLDN individuals according to the diameter of their fasting (8-hour fast) VLDL, LDL and HDL particles, determined by nuclear resonance spectroscopy. LCA is a form of cluster analysis that groups individuals based on similarities within specified measures, and uses an iterative approach to determine the number of groups (classes) that best explains the population variance and covariance in the measures . Initiale in SAS . As the LCA grouped all GOLDN individuals into 8 classes (groups) according their fasting VLDL, LDL and HDL diameters. For two groups N = 251), the average number of MetS features per member , using a TaqMan assay with allele-specific probes on the ABI Prism 7900HT Sequence Detection System  according to the standardized laboratory protocols.LPL codons 9, 291, and 447, namely, D9N, M107 and S447X were chosen for literature reports of genetic associations or lipid-related biological function. The minor allele frequency (MAF) of M107 was 0, and so excluded from analysis.Three nonsynonymous cSNPs at χ2 analysis. For genotype-phenotype associations, regression analysis was conducted using the "PROC GENMOD" command with genotype frequency, age, age2 and age3, sex, and center of data collection as predictors, and LCA group as the outcome. Pedigree was treated as a fixed random effect. To increase power, carriers of the minor allele for each genotype were compared to non carriers.All analyses were conducted in SAS v9.2. Hardy-Weinberg equilibrium (HWE) was determined using Lipoprotein, demographic and MetS-related characteristics are shown in Table P < .05). At the D9N locus, individuals were either homozygous for D9 allele (frequency = .94) or heterozygous (frequency = .06). The S447X locus showed individuals who were homozygous for the major allele , the minor allele  or heterozygous (frequency = .16).Genotype frequencies did not deviate from HWE expectations (P = .04).The D9N minor allele MAF = .10) did not show a group association  which, in turn, is associated with the higher IR, WC, fasting TG and glucose and diabetes prevalence among groups where individuals meet ATP-III criteria for the MetS. Given the small sample size, and novelty of the phenotype (lipoprotein diameter pattern) replication in additional studies is warranted.The associations observed in this study must be viewed with a number of considerations. These include the small sample size combined with the low MAF for both variants, and the restriction of results to white Americans of European descent. It was this modest sample size that precluded gender stratified analyses. Nonetheless we provide evidence that the GOLDN: Genetics of Lipid-Lowering Drugs Network; HDL: High-density lipoprotein; LDL: Low-density lipoprotein; LPL: Lipoprotein Lipase; MetS: Metabolic syndrome; TG: Triglycerides; VLDL: Very low-density lipoprotein; WC: Waist circumferenceThe authors declare that they have no competing interests.All authors read and approved the final manuscript. ACW carried out the analysis and wrote the manuscript, SG, WTG, EKK, IBB, HKT, MYT, PNH and JMO helped with critical revision of the manuscript, DKA is PI of the study and helped with critical revision of the manuscript.


High meat consumption, especially red and processed meat consumption is associated with an increased risk of several cancers, however, evidence for oral cavity and oropharynx cancer is limited. Thus, we performed this meta-analysis to determine the association between intakes of total meat, processed meat, red meat, and white meat, and the risk of oral cavity and oropharynx cancer.Electronic search of Pubmed, Embase, and Cochrane Library Central database was conducted to select relevant studies. Fixed-effect and random-effect models were used to estimate summary relative risks (RR) and the corresponding 95% confidence intervals (CIs). Potential sources of heterogeneity were detected by meta-regression. Subgroup analyses and sensitivity analysis were also performed.12 case–control studies and one cohort study were included in the analyses, including 501,730 subjects and 4,104 oral cavity and oropharynx cancer cases. Pooled results indicated that high consumption of total meat, red meat, and white meat were not significantly associated with increased risk of oral cavity and oropharynx cancer , while the high consumption of processed meat was significantly associated with a 91% increased risk of oral cavity and oropharynx cancer . Sensitivity analysis indicated that no significant variation in combined RR by excluding any of the study, confirming the stability of present results.The present meta-analysis suggested that high consumption of processed meat was significantly associated with an increased risk of oral cavity and oropharynx cancer, while there was no significantly association between total meat, red meat or white meat and the risk of oral cavity and oropharynx cancer. More prospective cohort studies are warranted to confirm these associations. Oral cavity and oropharynx cancer are the tenth most common cancer and seventh most common cause of cancer-related mortality worldwide The present meta-analysis was conducted following the Preferred Reporting Items for Systematic reviews and Meta-Analyses guidelines(PRISMA) Two reviewers independently selected eligible studies. Disagreement between the two reviewers was settled by discussing with the third reviewer. Studies were selected if they met our criteria (i) had a case-control or cohort design; (ii) evaluated the association between meat  consumption and the risk of oral cavity and oropharynx cancer, and (iii) presented odds ratio (OR), relative risk (RR), or hazard ratio (HR) estimates with its 95% confidence interval (CI).When there were multiple publications from the same population, only data from the most recent report was included in the meta-analysis and the others were excluded. Studies reporting different measures of RR like risk ratio, rate ratio, hazard ratio, and odds ratio were included in the meta-analysis. In practice, these measures of effect yield a similar estimate of RR, since the absolute risk of oral cavity and oropharynx cancer is low.The following data was collected by two reviewers independently using a purpose-designed form: name of the first author, publishing time, study region, study design, study period, number of cancer cases and subjects, dietary assessment method, the exposure of meat intake, quantity of intake, the study-specific adjusted ORs, RRs, or HRs with their 95% CIs for the highest category of meat consumption versus the lowest, confounding factors for matching or adjustments.We used Newcastle-Ottawa scale to assess the methodologic quality of cohort and case-control studies. The Newcastle-Ottawa Scale contains eight items that are categorized three categories: selection , comparability , and exposure/outcome . A ‘‘star’’ presents a ‘‘high-quality’’ choice of individual study. The full score was 9 stars, and the high-quality study was defined as a study with≥6 awarded stars.2 statistics. For the Q statistic, a P value<0.10 was considered statistically significant for heterogeneity; for the I2 statistic, heterogeneity was interpreted as absent (I2: 0%–25%), low (I2: 25.1%–50%), moderate (I2: 50.1%–75%), or high (I2: 75.1%–100%) Heterogeneity was assessed using the Cochran Q and IThe detailed steps of our literature search are shown in 2 = 82.9%, Q = 46.87, P<0.001). There was no indication of a publication bias, either from Egger ’s test (P = 0.780) or from Begg ’ s test (P = 0.835 ). There was no indication of a publication bias, either from Egger ’s test ( P = 0.999) or from Begg ’ s test ( P = 0.297)  has been found to be associated with several tumors, such as colorectal adenomas Red meat is a source of heme iron, which is more bioavailable than non-heme iron. Heme iron is contributed to carcinogenesis in rodents by generating free radicals and inducing oxidative stress The strength of the present meta-analysis lies in a large sample size  and no significant evidence of publication bias. All studies adjusted for smoking, and most studies adjusted for some potential confounders, including age, sex, and alcohol consumption. Furthermore, our findings were stable and robust in sensitivity analyses. However, several limitations to this meta-analysis should be noted. Firstly, as a meta-analysis of observational data, the possibility of recall and selection biases can’t be ruled out. Compared with case-control studies, cohort studies are less susceptible to bias due to their nature. However, the present meta-analysis included only one cohort study, so more prospective cohort studies are needed to confirm the association in the future. Secondly, we did not search for unpublished studies, so only published studies were included in our meta-analysis. Therefore, publication bias may have occurred although no publication bias was indicated from both visualization of the funnel plot and Egger’s test. Thirdly, none of the included studies adjusted for betel-quid chewing, which is one of the primary risk factors for oral cavity and oropharynx cancer. Lastly, due to different methods used to report meat intake among studies, we failed to carry out a dose-response analysis between meat intake and the risk of oral cavity and oropharynx cancer.In conclusion, the present meta-analysis suggested that a high intake of processed meat was significantly associated with an increased risk of oral cavity and oropharynx cancer, while there was no significantly association between total meat, red meat or white meat and the risk of oral cavity and oropharynx cancer. More prospective cohort studies are warranted to confirm these associations.Checklist S1(DOC)Click here for additional data file.


NQO1) gene C609T polymorphism (rs1800566) and lung cancer has been widely evaluated, and a definitive answer so far is lacking. We first conducted a case-control study to assess this association in northeastern Han Chinese, and then performed a meta-analysis to further address this issue.The association between NAD(P)H:quinone oxidoreductase 1  method. Meta-analysis was managed by STATA software. Data and study quality were assessed in duplicate. Our case-control association study indicated no significant difference in the genotype and allele distributions of C609T polymorphism between lung cancer patients and controls, consistent with the results of the further meta-analysis involving 7286 patients and 9167 controls under both allelic (odds ratio (OR) = 0.99; 95% confidence interval (CI): 0.92–1.06; P = 0.692) and dominant  models. However, there was moderate evidence of between-study heterogeneity and low probability of publication bias. Further subgroup analyses by ethnicity, source of controls and sample size detected no positive associations in this meta-analysis.NQO1 gene C609T polymorphism with lung cancer risk, even across different ethnic populations.Our study in northeastern Han Chinese, along with the meta-analysis, failed to confirm the association of  Lung cancer is one of the common malignancies, and nearly 1.3 million new cases are diagnosed annually worldwide NQO1) is a promising candidate in the pathogenesis of lung cancer NQO1 gene was observed to be over-expressed NQO1 gene responsible for its enzyme activity, further accountable for lung carcinogenesis. The transition of C to T at position 609 (rs1800566) of NQO1 gene can lead to reduced activity of quinone reductase The gene encoding NAD(P)H:quinone oxidoreductase 1  or enhanced CT or positron emission computed tomography (PET)-CT scan, which was confirmed by clinical doctors of respiratory medicine. Those who were susceptible to lung cancer were further pathologically confirmed by biopsy, and those with normal CT or enhanced CT or PET-CT results were treated as cancer-free controls in this study. Clinical subtypes of lung cancer included squamous cell cancer, adenocarcinoma, small cell cancer and unspecified lung cancer. Age and gender were recorded at enrollment. The status of cigarette smoking and alcohol drinking were defined at the time of the survey. Smoking was expressed by percent of ever or current smoking. Drinking was categorized as never, ever or current drinking. Here, current drinking referred to consumption of at least one alcoholic drink during the past 30 days.Blood samples (1 mL) were collected, and genomic DNA was extracted from white blood cells using the TIANamp Blood DNA Kit . Genotyping was conducted using the PCR-LDR (ligase detection reactions) method by ABI 9600 system  2 test for categorical variables. To avoid gross genotyping error, C609T polymorphism was checked for consistency with Hardy-Weinberg equilibrium by χ2 test. In view of age-matched patients and controls, genotypes were compared by conditional logistic regression analysis under assumptions of additive, dominant and recessive models of inheritance, respectively. Statistical significance was accepted as P<0.05.Comparisons between lung cancer patients and controls were conducted by unpaired t-test for continuous variables and by χThis meta-analysis is reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guideline (please see PRISMA checklist: http://www.wanfangdata.com.cn) were searched up to July 2012 for articles investigating the association between C609T polymorphism and lung cancer risk. The subject terms used were “lung cancer” or “lung neoplasm” and “NAD(P)H:quinone oxidoreductase” or “NQO1”, annexed with “gene” or “allele” or “genotype” or “variant” or “polymorphism” or “mutation”. Articles written in English or Chinese language and studies performed in human subjects were identified. The search result was supplemented by reviews of reference lists for all relevant studies and review articles. In addition, if there were shared or duplicated samples between studies, we recruited those with the large sample size.HuGE Navigator and PubMed, as well as Wanfang database  on a retrospective or nested case-control design; (ii) adopt validated genotyping method; (iii) provide genotype counts of NQO1 gene C609T polymorphism examined with lung cancer are described in Study quality was evaluated by using a quality assessment score explored for genetic association studies by Thakkinstian et al 2 test, and heterogeneity was assessed by the inconsistency index I2 statistic (ranging from 0 to 100%) which is defined as the percentage of the observed between-study variability that is due to heterogeneity rather than to random error In the meta-analysis, the random effects model using the DerSimonian and Laird method was employed to combine the individual effect size estimates to calculate pooled weighted ORs, and the estimate of heterogeneity was determined using the Mantel-Haenszel model. Between-study heterogeneity was explored by the χI2 and Egger’s statistics, statistical significance was set at 0.1. All statistical analyses were managed by STATA software (version 11.0).Publication bias was assessed by the Begg’s funnel plot, Egger’s test and the trim and fill method The demographics and risk factors of the study population are summarized in The success rates of genotyping for C609T polymorphism were 99.71% and 99.17% in patients and controls, respectively. Genotype distributions of examined polymorphism respected Hardy-Weinberg equilibrium in controls (P>0.05). There was no significant difference in the genotype and allele distributions of C609T polymorphism between lung cancer patients and controls, and this non-significance was also mirrored under assumptions of the additive , dominant  and recessive  models .The initial search yielded 83 potentially relevant articles. After applying the inclusion/exclusion criteria, 22 articles were eligible for inclusion. A flow chart schematizing the process of selecting and excluding articles with specific reasons is shown in Since more than one study group was included in some articles, we treated them separately. In total, 30 separate studies plus the present study encompassing a total of 7286 patients with lung cancer and 9167 controls were finally meta-analyzed, with 12 studies performed in Asians NQO1 gene C609T polymorphism with lung cancer under both allelic  and dominant  models, and this association suffered from significant evidence of heterogeneity between studies  (Egger = 0.608 and 0.81)  . Howevernd 0.81) .I2 = 0.0%) or publication bias (PEgger = 0.192). Upon stratification by source of controls, risk magnitude was relatively stronger in hospital-based studies than in population-based studies, whereas heterogeneity and publication bias tangled the former. Restricting analysis to studies with ≥500 patients still detected no material changes in risk estimates in both allelic and dominant models, indicating the robustness of our results.To account for potential sources of heterogeneity, we conducted a set of subgroup analyses according to ethnicity, source of controls and sample size . DespiteNQO1 gene C609T polymorphism as a promising candidate for lung cancer, our case-control study in northeastern Han Chinese, along with the meta-analysis, failed to confirm this relation, even across different ethnic populations. This non-significance was also reflected in larger sample-size studies, which are less prone to chance results, indicating the robustness of our findings. To the authors’ knowledge, this is the most comprehensive meta-analysis investigating the genetic susceptibility of NQO1 gene C609T polymorphism to lung cancer.Although numerous studies have regarded NQO1 gene C609T polymorphism with lung cancer With the increase of genetic association studies, it is highly encouraged to synthesize available data to resolve persistent difficulties in obtaining robust, replicable results. Considering the fact that most common genetic defects usually make a small-to-moderate contribution to future disease risk, this study urges the necessity of very large sample sizes to drive sufficiently precise estimates between genetic variation and disease. Several individual studies have reported positive signals of NQO1 gene C609T polymorphism with lung cancer. Second, the results of the present case-control study were in line with that of the corresponding meta-analysis, and restricting analyses to larger studies generated the similar findings. Third, our results are less prone to selection bias in view of low probability of publication bias.Several strengths distinguishing the present investigation merit adequate consideration. First, this is to date the largest synthesis exploring the association of NQO1 gene, and did not cover other susceptibility genes or polymorphisms. Given these limitations, we cannot jump to a conclusion until further verification of our findings in vitro, in vivo and in large prospective studies.In addition, some limitations should be considered when interpreting our findings. First, the cross-sectional design of included studies in this meta-analysis may preclude comments on causality, and a survival bias could not be excluded. Second, as with all meta-analyses, publication bias might have occurred because our analyses were based entirely on published studies from English- and Chinese-language journals. Third, although the adopted random-effects model takes both a between-study variance and the within-study variances into account, this model cannot be regarded as a panacea for heterogeneity NQO1 gene C609T polymorphism with lung cancer risk, even across different ethnic populations. Nevertheless, for practical reasons, we hope that this study will not remain just another endpoint of research instead of a beginning to establish the background data to further investigate the molecular mechanisms of NQO1 gene and lung cancer.To sum up, this case-control study in northeastern Han Chinese, along with the comprehensive meta-analysis, failed to confirm the association of Table S1Checklist of items to include when reporting a systematic review or meta-analysis (diagnostic review consisting of cohort studies).(DOC)Click here for additional data file.Table S2Criteria for quality assessment of genetic association of NQO1 gene C609T polymorphism with lung cancer.(DOC)Click here for additional data file.


Dear Dr. Maureen McCormick,We have carefully read with great interest your comments and concerns about the statistical results of our study. We would like to make some remarks.p = 0.3).If we repeat the statistical analysis of our data using an analysis of variance for repeated measures, we will obtain statistically significant results similar to our previous results, both globally or in pairs except for basal and 3-month interleukin-6 (IL-6) levels (p < 0.001) in the levels of IL-6, adiponectin and C-reactive protein. We have also found statistical differences for tumour necrosis factor-alpha but with the variations described in the study.We have used a parametric analysis because our sample is composed of more than 30 patients, wherein this kind of test is appropriate. However, if we use the Friedman non-parametrical test for our data, we will still obtain statistically significant results similar to the results that we have described in our article. There was a globally marked statistically significant reduction for the whole duration of the study (We appreciate sincerely your point of view. We are sure that you will help us to improve the quality of our article.Best regards,Fátima Illán Gomez


IDS) mutations. Recent studies in MPS II carriers did not find clinical involvement, but these were mainly performed by anamnesis and patients’ self-reported description of signs and symptoms. So although it is rare in heterozygous carriers, investigations in other types of inherited X-linked disorders suggest that some clinical manifestations may be a possibility. The aim of this study was to evaluate the clinical pattern in female carriers of MPS II and to determine whether clinical symptoms were associated with the X-chromosome inactivation (XCI) pattern and age.Mucopolysaccharidosis type II (MPS II) is an inherited X-linked disease associated with a deficiency in the enzyme iduronate 2-sulfatase due to iduronate 2-sulfatase gene  quantification, karyotype and pattern of XCI.Female carriers of MPS II were genetically identified by molecular analysis of Ten women were included in the study. The mean age of the participants was 40.2 ± 13.1 years. Six carriers presented a skewed XCI pattern, 3 of whom  had increased levels of GAGs in the urine and showed typical MPS II clinical manifestations, such as skeletal anomalies, liver abnormalities, carpal tunnel syndrome, recurrent ear infection, hypoacusia and more frequent severe odontological problems without coarse facial features.This is the first study performing a comprehensive evaluation of heterozygous MPS II carriers. Our results provide evidence of possible progressive, age-dependent, mild clinical manifestations in MPS II female carriers with a skewed XCI pattern, most likely affecting the normal allele. Further comparative studies with systematized clinical examinations in larger age-stratified populations of MPS II female carriers are required. IDS). The subsequent lack of glycosaminoglycan (GAGs) catabolism leads to an accumulation of dermatan sulfate and heparan sulfate in the lysosomes of many tissues, which makes MPS II a multisystem disease. MPS II includes the following main manifestations: short stature, dysostosis multiplex, joint contractures, coarse facies, hepatosplenomegaly, deafness, recurrent ear and sinopulmonary infections, obstructive airway disease, valve abnormalities and in several cases, mental impairment. Therefore, its management requires a multidisciplinary approach and specific enzyme replacement therapy, which is now available and which may change the natural history of the disease [Mucopolysaccharidosis type II , or Hunter syndrome, is one of the most common types of X-linked recessive inherited disorder with an estimated incidence between 1:110,000 and 135,500 live births . It is cMPS II is an X-linked recessive condition, in which female patients are infrequent. Moreover, in MPS II the X chromosome carrying the mutant allele is expected to be preferentially inactivated in some cells like chondrocytes or hepatocytes. Consequently, MPS II heterozygous subjects are rarely affected . X-chromAlthough it could be expected that females present 50:50 of active maternally and paternally derived X chromosomes after XCI, the most common ratios are 60:40 or 70:30 [The presence of two alleles carrying pathological mutations or a structural X-chromosome abnormality simultaneously leads to symptomatic female heterozygotes . To dateRecently, several clinical studies were designed to identify any clinical manifestations in heterozygous female carriers of MPS II. No evidence of clinical involvement was found, despite lower plasma and leukocyte I2S activities ,19. NeveIn contrast to previous studies in which the collection of the data was mainly performed by anamnesis and patients’ self-reported description of sign and symptoms, the aim of this cross-sectional study was to evaluate those clinical features using a broad panel of clinical examinations and complementary tests in ten female carriers of MPS II. In addition, we evaluated clinical symptoms according to the XCI pattern and age of participants.We included heterozygous mothers and other heterozygous female relatives of MPS II male patients, previously identified by genetic analysis, included in the Spanish Hunter Outcome Survey (HOS) who were being seen at participating centers. HOS is a worldwide multi-center observational long-term follow-up registry, sponsored by Shire HGT, which is open to all patients diagnosed with the disease . This reThe clinical data were collected during carriers’ visits to the centers by five clinicians from the Hunter Spanish Expert Council, a group of reference in the diagnosis and management of MPS II in Spain. Comprehensive anamneses were obtained, including information regarding the age or degree of relationship with the proband. A systematical investigation on the extent and distribution of physical involvement in female carriers of MPS II was conducted in 10 women using standardized clinical examination protocols. Complete physical examination by systems and organs was performed including full ophthalmological evaluation, brain-evoked auditory response, electrocardiogram, echocardiogram, pulmonary function tests, abdominal sonogram, skeletal survey, cognitive assessment and neurophysiological studies . A symptomatic carrier should have the characteristic signs and symptoms classically associated to MPS II. The following additional analyses were also performed: hematimetry, general biochemistry (including liver enzymes), quantification of GAGs in urine, karyotypes and XCI studies.Total GAGs were measured according to an improved dimethylmethylene blue (DMB) test . The norThe cytogenetic analysis was performed on metaphase chromosomes obtained from phytohemagglutinin (PHA)-stimulated peripheral blood lymphocytes following standard procedures. All chromosome preparations were G-banded and analyzed with a minimum resolution of 550 to 600 bands .The X-inactivation pattern was determined from peripheral lymphocytes by polymerase chain reaction (PCR) analysis of a polymorphic CAG trinucleotide repeat in the polyglutamine region of the androgen receptor (AR) gene . The XCITen female carriers of MPS II from 6 unrelated families with no parental consanguinity participated in the study. The mean age of the participants was 40.5 ± 13.1 and ranged from 17 to 67 years. The majority of the participating women were mothers (n = 6) of previously diagnosed MPS II patients recruited in the HOS registry, but there was also one grandmother, one aunt, one sister and one cousin.IDS were seen in five families and a small deletion in one. Only two of the missense mutations were previously described (c.998C>T and c.1048A>C). The karyotypes were normal in all women (data not shown). Extreme skewing XCI pattern was not identified in any of them. Moderately skewed XCI pattern was found in 6 women, of whom 4 were 40 years or older. Three out of six had increased GAGs. Therefore, a conjunction of skewed XCI pattern and GAGs elevation was observed in 2 / 5 aged carriers (≥ 40 years) and 1 / 5 in the group (< 40 years).The carriers’ information at baseline, including medical history and/or physical examination, is presented in Additional file The results of the clinical examinations and complementary examinations are also described in Additional file 5 in 5 / 9 carriers (Data not shown). The neurophysiological examination detected 3 / 5 women with mild to moderate CTS. The cognitive assessment identified 5 / 7 females with normal intelligence quotient (IQ) scores, one with a low IQ and the oldest female carrier with Hunter manifestations who presented a limited borderline score, according to the Kaufman Brief Intelligence test and the Wechsler Intelligence Scale for Adults. These two females were from the same family.Overall, the laboratory data revealed that platelets were increased up to 4.83 × 10Echographics and imaging exams were not performed in all women for technical reasons. Abdominal imaging was obtained from 6 participants, with hepatic anomalies observed in 3 who also showed other Hunter manifestations . All 3 carriers with increased GAG levels presented degenerative bone changes. The 42-year old carrier (number 2) showed hip dysplasia and typical Hunter paddle-shaped ribs  , therefoXCI increases in tissues with age, reaching up to 40% of skewed lyonization in women aged 60 or over . The ageUnfortunately, I2S enzyme activity was not measured in these women. It is already known that MPS II carriers show lower plasma and leukocyte I2S activities when compared with no carriers but this reduction was not associated, in Schwartz study, either with increased levels of urinary GAGs or with the occurrence of clinical manifestations . FurtherPinto et al. explained that the major differences in clinical manifestations among X-linked diseases may depend on the cell autonomy of the gene product involved and, therefore, on the occurrence of cross-correction mechanism, which was deficient in Fabry disease and preserved in MPS II . It was IDS activity, urinary levels of GAGs, karyotyping and conducted an X-inactivation assay [Previous investigations on MPS II were based on data from medical history and patients’ anamnesis about signs and symptoms in organs and systems typically involved in MPS II ,19. In ton assay . TherefoWe found certain clinical signs in the whole group of carriers, such as CTS diagnosed in 4 / 6 women and mild hepatic pathologies described in 3 / 6 participants. Additionally, moderate to severe periodontal disease or dental abscess in 6 / 9 participants and an elevation of platelets was observed in 5 / 9 participants. We are not aware of previous reports of platelet alterations associated with this type of mucopolysaccharidosis and certainly we cannot describe the practical significance of this finding.Overall, we found 3 carriers aged 38, 42 and 52 showing some typical MPS II clinical manifestations, including recurrent acute otitis, bilateral neurosensorial deafness, dentature since their twenties, hepatomegaly, skeletal anomalies and mild to moderate CTS, skewed XCI and GAGs elevation. Subjects aged 42 and 52 years  are sisters and signs and symptoms of the disease were more clearly evident in the older women, so it is possible that MPS II’s penetrance and clinical severity index in female carriers increase with age.It would have been interesting to study also non-heterozygotes females as part of a control group, because some of these clinical findings may be commonly found in healthy population. Nevertheless, the work was conducted inside the public health care system and we were limited given the costly and comprehensive work-up to be done in females without added risk factors (such as MPS II carriers). The small population of our study makes it difficult to reach a conclusive result, but our data provide traces of subtle clinical and biochemical signs in female carriers of MPS II.These results suggest that, like other X-linked diseases, MPS II heterozygotes may show a progressive disease phenotype, and this appears to be associated with a significant skewing of X-inactivation, presumably in the normal allele. The evolution of signs and symptoms is often a better indicator of MPS II involvement than a static snapshot of the presence or absence of certain manifestations. Therefore, it is important to monitor changes over time. It would be convenient that MPS heterozygotes are monitored closely at least every 12–24 months thereafter at a centre with experience. Assessments should include evaluation of the musculoskeletal and cardiovascular systems, ears, airways, eyes, skin, nervous system, abdomen and gastrointestinal system, as outlined in Additional file However, further comprehensive studies that look for subtle signs and symptoms of this disease are required in a larger age-stratified female carrier population.AR: Androgen receptor; BAEPs: Brainstem auditory evoked potentials; CTS: Carpal tunnel syndrome; DMB: Dimethylene blue; GAG: Glycosaminoglycans; HOS: Hunter Outcome Survey; IDS: Iduronate 2-sulfatase gene; IQ: Intelligence quotient; I2S: Enzyme iduronate 2-sulfatase; MPS II: Mucopolysaccharidosis type II; MRI: Magnetic resonance imaging; PCR: Polymerase chain reaction; XCI: X chromosome inactivation.E G-N, MR D-J, C A-M, R C-C, ML C, E G-G, and O A-L are members of the Spanish HOS (Hunter Outcome Survey), which receives financial support from Shire Human Genetic Therapies. E G-N is a member of the HSEEC (Hunter Syndrome European Expert Council), which receives financial support from Shire Human Genetic Therapies. Except for the editorial assistance acknowledged below, the authors did not receive any financial support for the project presented in this manuscript.EG-N has contributed in the study design, recruitment of participants and in the collection of their data, as well as in the analysis and interpretation of results. EG-N also participated in drafting the paper and has revised the intellectual content to give final approval of the manuscript. MRD-J, CA-M, RC-C, MLC, EG-G, and OA-L were involved in the recruitment of subjects, data collection and analysis of results. All authors have critically read and revised the paper, and approved the final version to be published.Clinical, biochemical and genetic data in MPS II female carriers.Click here for file


Cytochrome P450 1A1 (CYP1A1) is a member of the CYP1 family, which is a key enzyme in the metabolism of many endogenous substrates and exogenous carcinogens. To date, many studies have examined the association between CYP1A1 MspI and Ile462Val polymorphisms and cancer risk in various populations, but their results have been conflicting rather than consistent.To assess this relationship more precisely, a meta-analysis based on 198 publications was performed. Odds ratios (OR) and corresponding 95% confidence intervals (CIs) were used to assess the association. The statistical heterogeneity across studies was examined with a chi-square-based Q-test.Overall, a significant elevated risk of cancer was associated with CYP1A1 MspI and Ile462Val polymorphisms for all genetic models studied. Further stratified analysis by cancer types revealed that the MspI polymorphism may increase the risk of lung cancer and cervical cancer whereas the Ile462Val polymorphism may contribute to a higher risk of lung cancer, leukemia, esophageal carcinoma, and prostate cancer. In the subgroup analysis by ethnicity, obvious associations were found in the Asian population for the MspI polymorphism while an increased risk of cancer was observed in Asians and Caucasians for the Ile462Val polymorphism.The results of this meta-analysis suggest that CYP1A1 MspI and Ile462Val polymorphisms contribute to increased cancer susceptibility among Asians. Additional comprehensive system analyses are required to validate this association and other related polymorphisms. Cytochromes P450 (CYP450s) are heme-containing enzymes important to phase I-dependent metabolism of drugs and other xenobiotics . StudiesCYP1A1 is mainly expressed extrahepatically, especially in epithelial tissues, and it is critical for the metabolism of many endogenous substrates and exogenous carcinogens. Because of CYP450 1A1’s ability to catalyze the first step in the metabolism of polycyclic aromatic hydrocarbons , CYP1A1 may contribute to the formation of highly reactive intermediates ,7 which http://www.cypalleles.ki.se) [Several polymorphisms of CYP1A1 have been described and current information can be found on the Human CYP allele nomenclature website (s.ki.se) . Accumuls.ki.se) ,11. Suscs.ki.se) . Two funs.ki.se) .To date, a number of meta-analyses have been performed to explore the association between the MspI and Ile462Val polymorphisms of CYP1A1 and various cancers including prostate, ovarian, breast, lung, and colorectal cancer and leukemia, to name a few that occur in different ethnic populations ,7,14-18.All papers regarding the association between CYP1A1 polymorphisms and cancer risk published up to December 31, 2012 were identified through comprehensive searches using the PubMed database with the following terms and keywords: ‘‘cytochrome P450 1A1”, ‘‘CYP1A1’’ and ‘‘polymorphism’’, ‘‘variation’’, ‘‘mutation’’ and these terms were also paired with ‘‘cancer’’, ‘‘tumor’’ and ‘‘carcinoma’’. The search was limited to human studies and English language papers.For inclusion, the studies must have met the following criteria: (a) having information on the evaluation of the CYP1A1 polymorphism and cancer risk, (b) using a case-control design, and (c) containing complete information about all genotype frequencies. Exclusion criteria included (a) studies not focused on cancer or CYP1A1 research, (b) reviews, (c) reports without usable data, and (d) duplicate publications.Information was carefully extracted from all qualified publications independently by two researchers (K Liu and SQ Wang) based on the inclusion criteria listed above. Disagreements were resolved through a discussion between the two researchers. The following information was collected from each included study using a standardized data collection protocol S1: the OR (odds ratios) and their 95% CIs  were used to determine the strength of association between CYP1A1 MspI and Ile462Val polymorphisms and cancer risk. The percentage weight determined by the precision of its estimate of effect and, in the statistical software in STATA, is equal to the inverse of the variance. The risks (ORs) of cancer associated with CYP1A1 MspI and Ile462Val polymorphisms were estimated for each study. The statistical significance of the summary OR was determined with the Z-test. In our meta-analysis, we examined the association between allele C of the MspI polymorphism and the risk of cancer compared to that of allele T. Also, additive (CC vs. TT and CC vs. CT), recessive (CC vs. CT + TT), and dominant (CC + CT vs. TT) genetic models were investigated. The same method was applied to the Ile462Val polymorphism. Stratified analyses were also performed with respect to cancer type , ethnicity, source of controls and sample size . Heterogeneity analysis was confirmed by the Chi-square-based Q-test. A P-value greater than 0.10 for the Q-test indicated a lack of heterogeneity among the studies, and then the fixed-effects model (the Mantel–Haenszel method) was used to calculate the summary OR estimate of each study. Otherwise, the random effects model (DerSimonian and Laird method) was used. The HWE in the control group was estimated by Fisher’s exact test and a P-value<0.05 was considered significant. An estimate of potential publication bias was performed using a funnel plot, in which the standard error of log (OR) of each study was plotted against its log (OR). An asymmetric plot suggests a possible publication bias. Funnel plot asymmetry was assessed by the method of Egger’s linear regression test, a linear regression approach to measure funnel plot asymmetry on the natural logarithmic scale of the OR. All statistical analyses were performed with the Stata software , using two-sided P-values.Seven hundred and ninety potentially relevant citations were reviewed, and 198 publications  met the inclusion criteria and were selected in our meta-analysis. The study search process is depicted in In terms of the MspI polymorphism, 37783 cases and 50536 controls from 148 case-controlled studies were available. Study characteristics are summarized in With respect to the Ile462Val polymorphism, 134 case–controlled studies were eligible (34466 cases and 44371 controls), comprising 67 studies with Asian populations, 45 studies with Caucasian populations, 3 studies with African populations and 19 studies with mixed populations. 52 studies were conducted on general populations, 52 were hospital based and 3 were mixed. There were 26 lung cancer studies, 25 breast cancer studies, 8 leukemia studies, 9 prostate cancer studies, 12 head and neck cancer studies, 8 colorectal cancer studies, 6 endometrial cancer studies, 3 cervical cancer studies, 4 ovarian cancer studies, 4 gastric cancer studies, 10 esophageal carcinoma studies, 3 hepatocellular cancer studies, 6 oral cancer studies and other cancers were categorized into the “others” group. Among the 134 case-control studies, 42 studies included a sample size≥500. Detailed study characteristics are summarized in Regarding genotyping methods, PCR–RFLP, TaqMan and allele-specific PCR methods were commonly used. For most studies, cancers were confirmed histologically or pathologically and all controls were chiefly matched for sex and age. In addition, the distribution of genotypes in the controls of all eligible studies was consistent with the Hardy-Weinberg equilibrium (HWE). The relationship between the MspI polymorphism and the risk of different kinds of cancer is summarized in Concerning the Ile462Val polymorphism data: the pooled ORs, along with their 95% CIs, are presented in detail in Take the CYP1A1 Ile462Val genotype for example, there was significant heterogeneity for allele contrast (G vs. A: P <0.001), the additive genetic model comparison (G/G vs. G/A: P <0.001 and G/G vs. A/A: P <0.001), the dominant model comparison (G/G+G/A vs. A/A: P <0.001), and the recessive model comparison (G/G vs. G/A+A/A: P <0.001). Using a meta-regression analysis to explore the source of heterogeneity for dominant model comparisons (G/G+G/A vs. A/A) by ethnicity, cancer types, source of controls, and sample size, we observed that sample size  contributed to substantially altered heterogeneity, which could account for 100% of the heterogeneity source. Simultaneously, we found that cancer types , ethnicity , or source of controls  did not contribute to the source of heterogeneity.The sensitivity analysis was conducted by abandoning certain studies, such as the study that did not conform to HWE, the HWE in the control group was estimated by Fisher’s exact test. Studies before and after the process of individual study omission which had a P-value<0.05 were determined not to conform to HWE. After individual study omission, the corresponding pooled OR was not altered significantly. Sensitivity analysis thus confirmed that the meta-analysis results were statistically robust and that our results were reliable and stable.Begg’s funnel plot and Egger’s test were performed to evaluate the literature publication bias. Regarding the CYP1A1 MspI polymorphism 2, the fCYP genes which are comprised of large families of endoplasmic and cytosolic enzymes, play a role in drug, steroid hormone, and procarcinogen metabolism. In humans, the CYPP450s complex  contains more than 15 different enzymes . Some CYPrevious studies about CYP1A1 polymorphisms and cancer risk have been inconclusive. To clarify any association, we conducted a meta-analysis of 198 publications. To the best of our knowledge, this is the first meta-analysis to evaluate the relationship between CYP1A1 polymorphisms and overall cancer risk. Our study also provides a subgroup analysis stratified by ethnicity, source of control, cancer type and sample size. Our results indicated that the MspI polymorphism C/C genotype was associated with an increased risk of cancers, especially for lung and cervical cancer among Asians and mixed populations, whereas the Ile462Val polymorphism G/G genotype was associated with an increased risk of lung cancer, leukemia, esophageal carcinoma, and prostate cancer among Caucasians and Asians.Because tumor origin could influence the results from meta-analyses, we performed subgroup analyses by cancer type. We found that CYP1A1 MspI and Ile462Val polymorphisms correlated with increased lung cancer susceptibility. Also, the MspI polymorphism C/C genotype is associated with an increased risk of cervical cancer. Interestingly, Gutman and co-workers  reportedIn the subgroup analysis by ethnicity, the MspI C/C polymorphism was found to confer an increased cancer risk among Asians and mixed population but not Caucasians or Africans. For the Ile462Val G/G polymorphism, statistically significantly elevated cancer risks were observed in Asians and Caucasians but not in Africans or in mixed descendant populations. The exact mechanism for the ethnic discrepancy is uncertain but differences in underlying genetic backgrounds and social factors among different populations studied may be important. Ethnically diverse subjects may have unique cultures and life-styles that can contribute to different genetic characteristics and susceptibility to specific cancers. Also, in this meta-analysis, the sample size and numbers of studies in African groups and mixed groups were not adequate to evaluate any association. Finally, selection bias, different matching criteria and misclassifications of disease status and genotyping may have contributed to the discrepancy. Overall, our data do suggest genetic diversity among different ethnicities.Other limitations of this study included heterogeneity, which can interfere with the interpretation of meta-analysis data. Although we minimized this likelihood by performing a careful search of published studies, using explicit criteria for a study’s inclusion and performing strict data extraction and analysis, significant interstudy heterogeneity nevertheless existed in nearly every comparison. In our meta-analysis, the sample size of studies among Africans and among several cancer types is small and limited. As a result, the sample size accounted for most of the heterogeneity source. However, we did not exclude the possibility that ethnic or tumor type differences may contribute to the relatively large heterogeneity. Simultaneously, heterogeneity may arise from differences in the selection of controls, as well as subject age distribution and lifestyle factors. In addition, lack of original data from reviewed studies limited our evaluation of potential interactions because the interactions between gene-to-gene, gene-to-environment, and even different polymorphic loci of the same gene that may modulate cancer risks. Finally, the quantity of published studies was insufficient for a comprehensive analysis, particularly for single types of cancer and Africans. A better analysis would include detailed individual data such as age and sex. Therefore, more studies with sufficient sample sizes and detailed information are warranted. Also, studies indexed by the selected databases were included for the meta-analysis, and some relevant published studies or unpublished studies with null results may have been overlooked which would bias our results.In conclusion, although significant heterogeneity from included studies existed, our meta-analysis provided evidence to support an association between the CYP1A1 MspI and Ile462Val polymorphisms and increased cancer risk. The effects of the two genotypes of each CYP1A1 polymorphism are diverse according to subgroup analysis stratified by ethnicity, cancer type, and source of control. In the future, strict selection of patients, well-matched controls, standardized and unbiased methods and larger sample sizes are essential. Gene-gene and gene-environment interactions should also be considered as well as ethnic-specific studies to investigate the role of the two functional polymorphisms in Africans and specific cancer types.Checklist S1PRISMA 2009 Checklist.(DOC)Click here for additional data file.File S1All eligible articles involved in this meta-analysis.(DOC)Click here for additional data file.Table S1Stratification analyses of the P value and 95% confidence interval for MspI polymorphism.(DOC)Click here for additional data file.Table S2Stratification analyses of the P value and 95% confidence interval for Ile462Val polymorphism.(DOC)Click here for additional data file.Table S3Characteristics of studies included in the meta-analysis for MspI polymorphism. A generalized distribution of MspI genotype frequencies for each included study is listed.(DOC)Click here for additional data file.Table S4Characteristics of studies included in the meta-analysis for Ile462Val polymorphism. A generalized distribution of Ile462Val genotype frequencies for each included studies is listed.(DOC)Click here for additional data file.