Relationship between Downregulation of DAL-1 and Carcinogenesis of Colorectal Adenocarcinoma

Objective To study the relationship of DAL-1 downregulation and carcinogenesis of colorectal adenocarcinoma.Methods RT-PCR was used to detect DAL-1 mRNA expression in colorectal cancer cell lines and colorectal adenocarcinoma tissues.BSP and MSP were performed to examine the DAL-1 promoter methylation status in colorectal cancer cell lines and colorectal adenocarcinoma tissues.5-aza-dC treatment was performed to verify the promoter methylation status of DAL-1 in colorectal cancer cell lines.Results Expression of DAL-1 was found in colorectal cancer cell lines;there was no significant difference between DAL-1 expressions among the cell lines.DAL-1 was significantly reduced in a portion of colorectal adenocarcinoma tissues.Frequency of DAL-1 downregulation was significantly higher in patients with lymph node metastasis or in Dukes C and Dukes D(P0.05).DAL-1 promoter methylation was rare phenomenon.Conclusion Downregulation of DAL-1 plays an important role in carcinogenesis of colorectal adenocarcinoma,especially in advanced colorectal adenocarcinoma.However,the gene promoter methylation doses not regulate the expression of DAL-1.