Demethylation of the CD133 gene is frequently detected in advanced colorectal cancer.

BACKGROUND

Recently, it has been reported that colorectal carcinoma is created and propagated by a small number of undifferentiated tumorigenic CD133(+) cells. Furthermore, it has been reported that CD133 expression is directly regulated by epigenetic modifications. Therefore, it is possible that CD133 expression by gene demethylation is related to colorectal carcinogenesis.

MATERIALS AND

METHODS

The methylation status of the CD133 gene was examined in primary carcinomas and the corresponding normal tissues derived from 48 patients with colorectal cancer using quantitative methylation-specific PCR (qMSP) and the correlation between the methylation status and the clinicopathological findings was evaluated.

RESULTS

Demethylation of the CD133 gene was detected in 19 out of the 48 (40%) primary colon carcinomas, suggesting that the demethylation of CD133 is frequently observed in colorectal carcinomas. The clinicopathological data were correlated with the demethylation results. A significant difference was observed in the maximal tumor size (p=0.0222). Moreover, a trend was shown toward preferentially developing lymph node metastasis in demethylated tumors (p=0.214).

CONCLUSION

CD133 was more frequently demethylated in advanced colorectal carcinomas.