The epigenetically-regulated miR-663 targets H-ras in K-562 cells.

miR-663 is a tumour suppressor that is potentially regulated by modification of CpG islands. Whether aberrant methylation is one of the reasons for miR-663 down-regulation in some malignant cells and whether miR-663 targets oncogenes warrants further research. In the present study, we report that the CpG islands in the upstream region of pre-miR-663 are aberrantly methylated in the k-562 cell line and in the white blood cells of some chronic myelogenous leukaemia patients, and also that H-ras is one of the genes targeted by miR-663. Over-expression of miR-663 may suppress proliferation of the k-562 cell line in part by enhancing cell apoptosis.