The Relationship Of P16 Gene Promoter CpG Island Methylation With Epithelial Ovarian Cancer

BackgroundThe pathogenesis of ovarian cancer is complex and the pathogenesis is not clear.Many related experiments have shown that different methylation levels of different genes are detected in ovarian cancer,which is considered to be closely related to the occurrence of ovarian cancer.As a tumor suppressor gene that negatively regulates cell cycle,P16 inhibits the transcription and expression of this gene when methylation occurs in its promoter region,resulting in malignant cell proliferation.Some scholars have detected the methylation of P16 gene in ovarian cancer,which is believed to be related to the occurrence of ovarian cancer.However,other scholars suggested that the methylation of P16 gene was not significantly correlated with ovarian cancer through meta-analysis.ObjectiveThe purpose of this study was to investigate the methylation changes of CpG island in P16 gene promoter region in epithelial ovarian cancer(EOC)tissue samples and explore its relationship with EOC.MethodsCollected 13 cases of ovarian tissue samples(including 8 cases of serous cystadenocarcinoma,1 case of mucinous cystadenocarcinoma and 1 case of endometrial carcinoma)diagnosed with EOC(stage III),and 2 cases of normal ovarian tissue samples underwent total hysterectomy and bilateral adnexectomy for uterine diseases in the hospitalized patients.Methylation status of P16 gene in samples was determined by methylation specific polymerase chain reaction(MS-PCR)and the optimal temperature for PCR primers amplification was evaluated.Real-time fluorescence quantitative PCR(qPCR)was used to determine the methylation state of the samples again,and the specific products of PCR were verified by clonal sequencing.Results1 MS-PCR method was used to detect the methylation status of P16 gene1.1 The incidence of P16 gene promoter CpG island methylation in EOC and normal ovarian tissue was 69.2%(9/13)and 50.0%(1/2),respectively.The methylation rate of P16 gene in EOC was 72.7%(8/11),100%(1/1),and 0%(0/1)in serous cystadenocarcinoma,mucinous cystadenocarcinoma,and endometrioid carcinoma,respectively.1.2 The experimental group and control group in the annealing temperature 60-56 ? electrophoresis stripe of specific PCR products,when there was a nonspecific product less than 54 ? stripe;2 The methylation status of P16 gene was detected by qPCRThe incidence of CpG island methylation of P16 gene promoter in EOC and normal ovarian tissue was 0%(0/13)and 0%(0/2),respectively,and the difference was not statistically significant when P>0.05 was compared between the two groups.ConclusionsThe P16 gene promoter CpG island studied in this experiment is not methylated,so it is not considered to be correlated with the incidence of EOC.