Screening And Identification Of Several Abnormal Methylation Genes In Gastric Cancer

Purpose:Genetic alteration is one of the biomarkers of human cancer. Recent studies have showed that promoter alterations in some specific genes are frequent in gastric cancer. By using a highthroughput mass spectrometry on matrix-assisted laser desorption/ionization time-of-flight silico-chips (Mass-Array) and Bisulfite-assisted genomic sequencing (BSP) strategies, we proposed to demonstrate whether DHRS3, a member of the short-chain dehydrogenases/ reductases family, is a potential novel epigenetic target gene in gastric cancer.Experimental:Design: Mass-Array and BSP were used to evaluate and quantify the promoter methylation level. The expression level was determined by real-time PCR. The correlation between the methylation status of the DHRS3 promoter and clinicopathological characteristics of gastric cancer was then assessed. Results:Experiments showed that the promoter of DHRS3 was hypermethylated in gastric cancer. In all 120 clinical samples, the DHRS3 promoter was determined significantly hypermethylated in the tumor samples compared with adjacent normal samples from patients (p<0.0001). The methylation status of DHRS3 was corresponded with the expression level of DHRS3 mRNA.Conclusions:Taken together, these data suggest that DHRS3 down-regulation is associated with promoter hypermethylation in gastric cancer, which may be useful for clinical molecular diagnosis.