The Research Between Cx32, Cx43Expression And Methylation In Different Developmental Stages Of Helicobacter Pylori-associated Gastric Cancer

Objective:To investigate the association between the expression of Cx32, Cx43mRNA and methylation degree during the sequential pathological stages from chronic superficial gastritis (CSG), chronic atrophic gastritis (CAG), intestinal metaplasia (IM), dysplasia (DYS) to gastric cancer (GC) infected by H.pylori.Methods:Twenty-four gastric mucoses in every sequential pathological stage were from patients infected by H.pylori as well as24normal gastric mucoses (NGM) with no infection according to the gastroscope and pathological analysis. The expression of Cx32, Cx43mRNA was measured by quantative real-time PCR, and the methylation degree of CpG island in Cx32, Cx43promoting area was measured by Methylation-Sepcific PCR(MSP), Bisulfite Benomic Sequence(BSP), and MassArray.Results:(1) The descending tendency in Cx32, Cx43mRNA expression occurred in developmental stages from CSG to GC with H.pylori infection (P<0.05), and lowest in GC. The changes in stages from CAG to GC differed significantly with NGM (P<0.05).(2) The ascending tendency in Cx32, Cx43promoter methylation occurred in developmental stages from CSG to GC with H.pylori infection (P<0.05), and highest in GC. The changes in stages from CAG to GC differed significantly with NGM (P<0.05).(3) It demonstrated strongly negative correlation between Cx32, Cx43mRNA expression and developmental stages of GC (P<0.05), while the positive correlation between Cx32, Cx43methylation and developmental stages of GC (P<0.001).Conclusion:The descending Cx32, Cx43mRNA expression occurred in gastric mucous with H.pylori infection in different stages of precancerous lesion and gastric cancer (from CAG to GC), which probably be resulted from promoter hypermethylation.