Abstract : Epigenetics is the study which involves the modifications in gene expression without changes in DNA
nucleotide sequences. Methylation of DNA and chromatin remodeling through histone proteins are believed to
be the most crucial epigenetic changes. Micro RNAs (miRNAs) are also shown to mediate the epigenetic gene
regulation in mammals.DNA methylation can activate or inhibit the differentiation of stem cells by affecting the
regulatory regions of its developmental genes like Oct4, Nanog and Sox2. In cancer, mutations in genetic as
well as epigenetic elements play a vital role. The epigenetic changes in cancer are distinct in that they can be
therapeutically reversed more easily. Aberrant DNA methylation (hypomethylation, hypermethylation) has its
role at the molecular level in a number of cancers. This review will provide an insight into the epigenetic
mechanisms involved in the regulation of stem cell specific genes Oct4, Sox2 and Nanog, alongwith the
epigenetic modifications leading to cancer.
Keywords: Cancer epigenetics, DNA methylation, Epigenetics, Histone modifications, Oct4, Sox2 and Nanog,
Stem cells.
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