RUNX3 gene methylation in ovarian cancer cell lines

RUNX3 is one of the suppressor gene in ovarian cancer, it is not clear whether the expression of RUNX3 is regulated by its promoter methylation or the demethylating agent 5-aza-2´-deoxycytidine. We carried out methylation - specific PCR (MSP) to investigate the methylation status of RUNX3 promoter region in human ovarian cancer cell line 3AO, KOV3 and normal ovarian epithelial cell NOEC. The methylation of RUNX3 promoter was found in tumor cells but not in NOEC. When treated with 5-aza-2´-deoxycytidine, the methylation was induced or completely reversed, the growth of tumor cells were notably inhibited, however, the agent did not affect the growth of NOEC. In conclusion, methylation of RUNX3 may be involved in the carcinogenesis of ovarian cancer and may serve as a predictive biomarker. The reversion of methylation by 5-aza-2´-deoxycytidine offers a novel therapeutic strategy for ovarian cancer.