The correlative analysis of indefinite dysplasia and dysplasia,and its p16 methylation in human gastric mucosa with Helicobacter pylori infection / 北京大学学报(医学版)

ABSTRACT

Objective:To compare the CpG island methylation status of p16 in subjects with gastric indefinite dysplasia or dysplasia,and investigate its association with exposure factors.Methods: Methylation status of p16 was determined by methylation specific PCR method and denaturing high-performance liquid chromatography analysis in 223 indefinite dysplasia and 130 dysplasia from Linqu County in Shandong Province,an area with high GC mortality rates.Multivariable analysis was used to analyze the relationship between p16 methylation and age,gender,cigarette smoking,alcohol drinking,and Helicobacter pylori infection.Results: The methylation frequency of p16 in indefinite dysplasia was not significantly different from that of dysplasia(28.3% vs.24.6%,P=0.46).No significant association was found between p16 methylation and age,gender,cigarette smoking,and alcohol drinking.In dysplasia,the association between p16 methylation and Helicobacter pylori infection was close to the statistical significance by univariate analysis that the relative risk of p16 methylation of the infected subjects(n=93) is higher than that of the uninfected subjects(n=37)(OR=2.62,95%CI 0.92 to 7.43,P=0.07).But by multivariate analysis,there was no association between them(P=0.11).Conclusion: The frequency of p16 methylation in gastric mucosa of indefinite dysplasia was similar to that of dysplasia.p16 methylation status was not associated with age,but might be significantly associated with Helicobacter pylori infection.