DNA Methylation Analysis Of Whole Genome Promoter In Prostate Carcinoma

Prostate cancer(PCa)is the most common tumor in the elderly men.Worldwide,the incidence of prostate cancer in men in second place in all malignant tumor.The incidence of prostate cancer in the United States has more than lung cancer,became the first men's health hazard of the tumor.According to the latest data,China's national cancer center prostate cancer since 2008 and became the highest incidence of urinary system tumor,incidence reached 9.92/100000 in 2009,ranked sixth in the male malignancies,mortality rate of 4.19/100000,in all men ranked ninth in the malignant tumor.However,the specificity and sensitivity of serum prostate specific antigen(PSA)levels were controversial.We aim to reveal a novel diagnosis biomarker in PCa.PART I PROMOTER DNA METHYLATION ANALYSIS REVEALS A COMBINED DIAGNOSIS CpG-BASED BIOMARKER FOR PROSTATE CANCERObjectives:We explored the differerce methylation of prostate cancer promoter region and mined the potimum diagnostic markers using bioinformatics analysis.We validated the methylation levels and mRNA expression of these markers,and explored the clinical diagnosis value and looked forward to find better biological diagnosis markers.Materials and methods: The differential methylated CpG sites between 423 primary PCa and 39 adjacent samples from TCGA,Illumina HumanMethylation 450 platform was analyzed.The diagnostic methylation markers were mined by using the Prediction Analysis of Microarrays(PAM)package in Bioconductor,then the GEO data was used to verify.Pyrosequencing was applied to improve methylation levels of 5 CpGs(cg06363129,cg08843517,cg05385513,cg07220448 and cg11417025)in our samples.Results: The Area Under ROC Curve(AUC)of 8 diagnostic methylation CpGs(cg06363129,cg08843517,cg03576469,cg05385513,cg07220448,cg11417025,cg20883831 and cg23824801)in TCGA data ranged from 0.910 to 0.939.Except for cg20883831 and cg23824801,the correlation between methylation level of other 6 sites and their expression in patients were significant(r>0.5 and p<0.001).The methylation level of cg06363129 had a significant difference between the groups of GS=7 and GS?8(P<0.05).Pyrosequencing in our samples confirmed that 4 diagnostic methylation sites(cg06363129,cg08843517,cg05385513 and cg11417025)had a high diagnostic efficacy.Conclusions: The combined diagnosis of 4 methylation CpGs sites(cg06363129,cg08843517,cg05385513 and cg11417025)in gene promoter has high tissue-specific and diagnostic efficacy for PCa.These results revealed a novel potential biomarker for diagnosis of the prostate cancer.Part II DNA METHYLATION ANALYSIS OF WHOLE GENOME PROMOTERIN PROSTATE CANCERObjectives : As one of the important epigenetic regulation modifications,the DNA methylationrapidly gained researchers' attention,because it occurs before precancerous lesion.In this study,we analyzed promoter differential methylation and identified biomakers for prostate cancer and examined methylated levels of biomarker of key genes.It aimed to explore the diagnostic value of methylationin prostate cancer clinically and the relationship between the prostate cancer promoter methylation pattern and its development.Materials and methods: We exploited and analysis DNA promoter differential methylation of 462 primary prostate cancer and paired 39 adjacent tissues from the Cancer Genome TCGA database.Bioinformatics to find the difference the methylation of promoter,After through the Receiver operating characteristic(ROC)curve in the diagnosis of methylated promoter performance assessment.And discrete map was obtained by Gradpad software has confirmed its expression product has relevance.Results: We found 992 differentially methylated promoters,and there were 663 hypermethylated and 329 hypomethylated promoters respectively.PAMR to select 5 promoter were ENSG00000161055 of SCGB3A1,ENSG00000213366 of GSTM2P1,ENSG00000144655 of CSRNP1,ENSG00000138356 of AOX1,ENSG00000213316 of LTC4 S gene.The diagnostic efficacy of was 0.920 of AUC curve.Finally discrete figure shows the five promoters related to express meaningful,P < 0.001.Conclusion: Our results reveal 5 promoters,included ENSG00000161055,ENSG00000213366,ENSG00000144655,ENSG00000138356 and ENSG00000213316,could be the novel potential biomarkers for prostate cancer diagnosis.