Hypermethylation of SFRP2 as a potential marker for stool-based detection of colorectal cancer and precancerous lesions

DNA methylation is a key mechanism of colorectal carcinogenesis. Analysis of aberrantly methylation in stool DNA might provide a novel strategy for noninvasive detection of colorectal cancer (CRC). To explore the feasibility of this approach, we have assessed the methylation status of secreted frizzled-related protein gene 2 (SFRP2) in stool samples from patients with CRC with respect to a series of healthy individuals and patients with benign colorectal diseases, using methylation-specific polymerase chain reaction. Methylated SFRP2 occurs in 94.2%, 52.4%, 37.5%, and 16.7% of patients with CRC, adenomas, hyperplstic polyps, and ulcerative colitis, respectively. Of the 24 normal individuals, only 1 revealed methylated DNA. The pilot study revealed that aberrant methylated SFRP2 could be detected frequently in stools from patients with CRC and precancerous lesions. Methylation testing of fecal DNA may be a simple, promising, and noninvasive screening tool for colorectal neoplasia.