An Overview of the Epigenetic Modifications of Gene Expression in Tumorigenesis

Abstract

The five leading causes of cancer-related deaths are lung (1,760,000 deaths), colorectal (862,000 deaths), stomach (783,000 deaths), liver (782,000 deaths), and breast (627,000 deaths) cancers. Epigenetic changes can alter chromatin compaction, leading to the regulation of gene expression without changing the primary DNA sequence. Epigenetic mechanisms are normally involved in cellular processes such as genomic stability, chromosome X inactivation, and embryonic development and differentiation. Similar to other types of chromatin modifications, DNA methylation has been verified to affect the expression of various genes. Any impairment in these mechanisms alters the regulation of gene expression and can contribute to malignant cell transformation. Over the past few years, extensive innovations within the field of epigenetics have encouraged its application as a major strategy for the treatment of important diseases such as cancer.

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