Epigenetic agents such as DNA methyltransferase inhibitors and inhibitors of histone deacetylase are currently used in clinical studies to reverse altered histone modifications and aberrant DNA methylation which can lead to tumor growth. Because epigenetic modifications are functionally equivalent to genetic changes and some have been linked to tumorigenic events, researchers have attempted to identify epigenetic mechanisms that may lead to disease such as cancer. Recent data has shown that the use of these agents positively influence the induction of down-modulated immunoactive(e.g. MHC class I or II), co-stimulatory and adhesive molecules on tumor cells, cytokine production and the expression of tumor-rejecting antigens. Therefore, the anti-tumor therapeutic potential of these agents is promising and are welcomed additions to the medicinal arsenal currently used in the fight against cancer.