EPIGENOME CHANGES AND THE SMOKING HABIT

Abstract

Introduction: Environmental factors such as cigarette agents are capable of altering the genome of the cells and lead to tumor development. Recently, the ability of the cigarette to cause alterations in the epigenome has also been investigated. Epigenome refers to information of the genome that is not related to the sequence of DNA bases. Objective: The aim of this study was to conduct a literature review about smoking and its association with the altered pattern of DNA methylation in tumor samples. Method: The research considered articles published from 2000 to 2010 in Pubmed database. Articles were selected by accessibility, excluding reviews and research on cell lines and animals. Results: The selected articles revealed that smoking can alter the epigenome even in organs not directly exposed as the mouth and lung, suggesting that cigarette smoking has a widespread effect, probably changing in some way the whole system of the individual. Some articles have reported changes in the pattern of DNA methylation in healthy tissues of smokers. Conclusion: Smoking-associated cancers may have an epigenetic mechanism involved even in organs not directly exposed. The presence of epigenetic changes in healthy tissue can serve as a warning to the clinician responsible for the patient, since it has been suggested to be as strong biomarker for many types of cancers and then it is a tool for diagnosis and treatment course. DESCRIPTORS Neoplasm. Cigarette. DNA. Genes. Genetic. Smoking. Methylation.