| Background:MM is the most aggressive malignant tumor with poor prognosis,the mortality of MM is increasing in recent years,which has become a serious threat to the life and health of our people.It is a hot and difficult problem to find specific prognostic indicators to guide the treatment of patients individually and improve the prognosis and survival rate of patients all over the world.Genetic factors play an important role in the occurrence and development of MM.GWAS has made outstanding contributions in identifying the susceptibility of MM genes.Previous studies have found some regions with genome-wide significance related to MM,but lack of studies on the biological function of gene loci on MM.GWAS pathway analysis can integrate the biological functions of signaling pathways,reflect the biological mechanism of disease occurrence and development more accurately,and provide an effective means for comprehensive research on genetic susceptibility of MM.Peroxisome is a ubiquitous dynamic organelle,which plays an important role in tumors characterized by metabolic abnormalities such as colorectal cancer,liver cancer,bladder cancer and so on.However,there are few studies on the effect of peroxisome signaling pathway genetic susceptibility on MM survival prognosis,and it has not been effectively verified in the population.Therefore,further study on MM and its confirmation in different populations is expected to provide an effective specific indicator for the prognosis of MM.Objectives:1.This research is based on 2 melanoma GWAS database,analysis the association of peroxisome pathway gene polymorphisms and survival of melanoma;2.To evaluate the effect of positive loci on survival prognosis of MM patients and establish prognostic prediction model of MM patients to improve the survival prognosis prediction ability;3.The influence of peroxisome pathway gene polymorphism positive loci on the survival prognosis of MM was further verified in cells and human tissues,providing a new biological prediction index and theoretical basis for the prognosis and individualized treatment of MM patients.Methods:For the discovery dataset,we extracted a genotyping dataset from The University of Texas MD Anderson Cancer Center(MDACC).We assessed the associations between 8,397 common single-nucleotide polymorphisms(SNPs)in 88 peroxisome pathway genes and melonoma survival in two-stage analysis.We then replicated the results in another dataset from the Nurse Health Study(NHS)/Health Professionals Follow-up Study(HPFS).Multivariate Cox regression analysis and statistical analysis with multiple test correction were used to select sites with statistical significance associated with melanoma survival.The effects of positive loci on MM survival and prognosis were evaluated by genetic model analysis,combination analysis and stratified analysis.For selected statistically significant loci,use the area under the curve evaluation prediction model for prognosis of melanoma prediction ability.Public databases,cytology and human tissues were used to verify the biological function of positive loci in genetic susceptibility to MM.Results:1.From MDACC dataset,we extracted 8,397 SNPs located in 88 peroxisome pathway of candidate genes,277 SNPs associated with melanoma screening after validation in the NHS/HPFS study,27 SNPs located on the four genes are statistically significant(P < 0.05 and BFDP < 0.8).Two independent SNPs associated with melanoma survival(TMEM135rs567403 C>G and PEX5 rs7969508 A>G)were finally selected,which were still statistically significant in multivariate regression analysis(P=0.003 and 0.031,respectively).2.The TMEM135 rs567403 G and PEX5 rs7969508 G alleles were found to be associated with an increased risk of death in melanoma patients(in the MDACC study,the P values of the additive model trend test were 0.036 and 0.030,respectively;In NHS/HPFS,the P values of additive model trend test were 0.040 and 0.004,respectively;In the combined study,P values of the trend test of the additive model are 0.023 and 0.001,respectively).The risk genotype TMEM135 rs567403 CG + GG and PEX5 rs7969508 AG +GG combination,according to the number of risk genotype(NRG)are divided into different genetic models,the higher the NRG score,the worse the melanoma survival,showing a dose-dependent pattern,with trend test P values of 0.002,0.003,and 0.0003 in the MDACC study,NHS/HPFS study,and combined study,respectively.In the NHS/HPFS dataset,the prognostic model included two identified independent SNP risk genotypes,and the ROC curve for 5-year specific survival showed a 16.83% improvement in predictive performance(54.05% vs.70.88%,P=0.003).3.MM cytological level experiment showed that the mRNA expression levels of TMEM135 and PEX5 of rs567403 C>G and rs7969508 A>G were significantly higher than those of human melanocytes,with statistically significant differences.4.Chi-square test in immunohistochemical human tissue samples showed that the rate of local and distant metastasis in immunohistochemical PEX5-positive patients was significantly increased,and Kaplan-Meier curve showed that the disease-free survival and overall survival in TMEM135-positive patients were significantly decreased.Conclusions:1.In this study,it was found that the polymorphisms of TMEM135 rs567403 C>G and PEX5 rs7969508 A > G in the peroxisome pathway were significantly associated with the survival of MM,and both the alleles of TMEM135 rs567403 G and PEX5 rs7969508 G could increase the risk of death from MM.2.In combination analysis,with the increase of the number of risk genotypes(TMEM135 rs567403 CG + GG and PEX5 rs7969508 AG + GG),the risk of death from melanoma increased gradually in a dose-dependent pattern.Adding polymorphisms of TMEM135 rs567403 G and PEX5 rs7969508 G in peroxisome pathway found in this study to the survival prediction model of melanoma can improve the prediction ability of the model.3.The TMEM135 rs567403 and PEX5 rs7969508 of peroxisome pathway are correlated with the survival prognosis of MM,which may affect the progression of MM through up-regulating the mRNA expression levels of TMEM135 and PEX5,which may be the molecular biological mechanism affecting the susceptibility of MM.4.Peroxisome pathway TMEM135 gene can significantly reduce the survival prognosis of patients,and PEX5 gene is an independent risk factor for local and distant metastasis of MM.The polymorphism of TMEM135 and PEX5 genes in peroxisome pathway can provide a new biological predictor and theoretical basis for the prognosis and individualized treatment of MM patients. |
PDF Full Text Request