Detection of SNCA and FBN1 methylation in the stool as a biomarker for colorectal cancer.

Aim. We examined the methylation status of SNCA and FBN1 genes in patients' paired tissue and stool samples for detection of colorectal cancer (CRC). Patients and Methods. 89 DNA tissue samples (normal/cancer) and corresponding stool samples were analyzed in our study. In addition, 30 stool samples were collected as healthy controls. Results. The methylation level of those samples was measured by methylation-specific polymerase chain reaction (MSP). The result shows that compared with the paired controls, both SNCA and FBN1 were significantly hypermethylated in CRC patients in tissue samples (P < 0.001). In the stool samples, hypermethylated SNCA and FBN1 were detected to be significantly higher than that in normal stool samples (P < 0.001). The combined sensitivity of at least one positive among the two markers in stool samples was 84.3%, with a specificity of 93.3%. In addition, our experiment suggested that the positive rates of SNCA and FBN1 in Dukes A stage were significantly higher than that of FOBT (P = 0.039; P = 0.006, resp.). Conclusion. We concluded that methylation testing of SNCA and FBN1 genes in stool sample may offer a good alternative in a simple, promising, and noninvasive detection of colorectal cancer.