Epigenetic regulation of miR-218 and its host gene, SLIT2 in breast cancer

Numerous studies have shown that microRNAs are deregulated in various types of cancer. Although miR-218 aberrant expression has been documented in various cancers, the epigenetic regulation of miR-218 is unclear in breast cancer. Our results demonstrate that treatment of breast cancer cells with demethylating agent, 5-azacytidine, resulted in increased expression of miR-218 and its host gene slit-2, suggesting that they are epigenetically regulated in breast cancer. The ectopic expression of miR-218 sensitize breast cancer cell to doxorubicin treatment. The results suggest that miR-218 is epigenetically regulated along with its host gene and function as a tumor suppressor in breast cancer. miR-218 and SLIT2 may have potential therapeutic value in combination with demethylating drug in breast cancer patients.