DNA methylation of ZIC1 and KLOTHO gene promoters in colorectal carcinomas and its clinicopathological significance

Abstract

To determine DNA methylation status of ZIC1 and KLOTHO gene in colorectal carcinomas and its relationship with clinicopathological features of patients. The mRNA expression of ZIC1 and KLOTHO genes in colorectal carcinomas was detected by real-time quantitative RT-PCR, and the promoter methylation status was detected by methylation specific PCR (MSP). The relationship of ZIC1 and KLOTHO methylation status with clinicopathological features of colorectal carcinoma was analyzed. The mRNA expression levels of ZIC1 and KLOTHO genes were significantly down-regulated in tumor tissues when compared to adjacent nontumor tissues (P<0.001). ZIC1 and KLOTHO methylation was detected in 80.0%(20/25) and 76.0%(19/25) of colorectal tumor tissues, respectively, and the both positive rate was 64.0%(16/25). The down-regulated expression of ZIC1 and KLOTHO in colorectal carcinoma may relate to promoter methylation. The detection of methylation of ZIC1 and KLOTHO gene potentially provides biomarkers for diagnosis of colorectal carcinoma.