Epi-Drugs and Epi-miRs: Moving Beyond Current Cancer Therapies

Epigenetic modifications determine phenotypic characteristics in a reversible, stable and genotype-independent manner. Epigenetic modifications mainly encompass CpG island methylation and histone modifications, both being important in the pathogenesis of malignancies. The reversibility of epigenetic phenomenon provides a suitable therapeutic option that is reactivation of epigenetically silenced tumor-suppressor genes. Inhibition of DNA methyltransferase, histone deacetylase and Aurora B kinase, individually or collectively, could feasibly prevent or reverse the impact of epigenetic silencing. MicroRNAs [miRNAs] are an important layer of epigenetic controlling of gene expression, and serve as diagnostic and prognostic biomarkers as well as treatment targets for several types of cancer. miRNAs are involved inepigenetically silencing or activation of genes, tumor-suppressor genes and oncogenes, and their modulation opens new horizons for designing novel cancer therapeutic agents.