Epigenetic regulation and cancer (Review)

Abstract

'Epigenetics' is defined as the inheritable changes in gene expression with no alterations in DNA sequences. Epigenetics is a rapidly expanding field, and the study of epigenetic regulation in cancer is emerging. Disruption of the epigenome is a fundamental mechanism in cancer, and several epigenetic drugs have been proven to prolong survival and to be less toxic than conventional chemotherapy. Promising results from combination clinical trials with DNA methylation inhibitors and histone deacetylase inhibitors have recently been reported, and data are emerging that describe molecular determinants of clinical responses. Despite significant advances, challenges remain, including a lack of predictive markers, unclear mechanisms of response and resistance, and rare responses in solid tumors. Preclinical studies are ongoing with novel classes of agents that target various components of the epigenetic machinery. In the present review, examples of studies that demonstrate the role of epigenetic regulation in human cancers with the focus on histone modifications and DNA methylation, and the recent clinical and translational data in the epigenetics field that have potential in cancer therapy are discussed.

Novel histone deacetylase inhibitors derived from Magnolia officinalis significantly enhance TRAIL-induced apoptosis in non-small cell lung cancer

“…Epigenetic alterations of tumor suppressor genes and the resulting altered cellular transformations are closely related to lung cancer progression and metastasis [1,3]. Given their dynamic and reversible characteristics, epigenetic variations are potential targets in lung cancer chemoprevention and treatment.…”

Downregulation of miR-129-2 by promoter hypermethylation regulates breast cancer cell proliferation and apoptosis

“…The methylation of CpG islands in gene promoters has been strongly linked to the silencing of the expression of tumor-suppressor genes in different types of cancers (14)(15)(16)(17). The hypermethylation of promoter CpG islands has been found to affect not only tumor-suppressor mRNAs, but also tumor-suppressor miRNAs.…”

Comprehensive investigation of aberrant microRNA profiling in bladder cancer tissues

“…MicroRNAs (miRNAs) are a class of small, non-coding RNAs of 19 to 24 nucleotides that post-transcriptionally regulate gene expression through RNA interference, gene silencing pathways [4][5][6][7][8][9][10]. Presently, 1881 precursors and 2588 mature miRNAs in human have been identified by the latest version of miRBase (v.21, http://www.mirbase.org/ on 24th, January, 2016) [11].…”