DNA Methylation and Cancer

Abstract

Introduction: Epigenetic is defined as the study of the mutations in DNA and histones that are heritable and do not change the sequence of DNA bases. Histone mutations may include: methylation, phosphorylation and acetylation. However, in the DNA molecule, only methylation occurs. It consists of the addition of a methyl group to the cytosine that usually precedes the guanine (CpG dinucleotide), and is present mainly in gene promoter regions. The DNA methylation participates in gene transcription, among other functions. Objective: The objective of this study was to review the literature about cancer and its association with the aberrant methylation pattern, as well as the disease prognosis and therapeutic results. Method: A complete review of the literature was carried out through electronic search in the Pubmed database. The time period comprehended by the study was 2000 to 2010. The articles were selected by accessibility, excluding reviews and research conducted on cell lines and animals. Results: The articles selected revealed that several types of cancer are associated with aberrant methylation patterns. In addition, the methylation pattern may help in the disease prognosis. Other studies show that methylation can be modulated by environmental factors such as diet, smoking and drugs. Conclusion: Based on the fact that epigenetic changes are potentially reversible, the importance of the epigenetic studies lies not only in better understanding cancer, but also in discovering the potential tumor markers and developing drug therapies.