Nutrigenetics, nutrigenomics and phenotypic outcomes of dietary low-dose alcohol consumption in the suppression and induction of cancer development: evidence from in vitro studies

It is known that the intake of alcoholic beverages may impair genetic and epigenetic regulatory events with consequent crucial effects on cell phenotypes and that its association with selected genotypes can lead to a different risk of cancer in the population. The aim of this review is to pick up selected studies on this topic and recapitulate some of the biochemical and nutrigenetic/nutrigenomic aspects involved in the impact of dietary low-dose alcohol consumption on the switching-on or -off of tumorigenic pathways. These include i) the existence of predisposing or protective human genotypes and the relationship between dietary compounds and alcohol in the promotion or inhibition of carcinogenesis; ii) the effects of other components of alcoholic drinks in the modulation of the expression of oncogenes and oncosuppressors, the autophagic flux and the onset of apoptosis, with examples of their cytospecificity; and iii) the role of alcoholic beverage consumption within particular dietary regimens, including the Mediterranean diet. Taking all the data into account, several alcohol-associated bioactive dietary compounds appear capable to modulate peculiar intracellular pathways predisposing to or protecting from cancer. Advances in the nutrigenetic, nutrigenomic and nutriepigenetic knowledge complementing the biochemical and molecular approaches will help in unveiling their impact on health outcome.

Alcohol Intake and Abnormal Expression of Brf1 in Breast Cancer

Breast cancer is the most common malignant disease of females. Overall, one woman in every nine will get breast cancer at some time in her life. Epidemiological studies have indicated that alcohol consumption has most consistently been associated with breast cancer risk. However, the mechanism of alcohol-associated breast cancer remains to be addressed. Little is known about the effects of alcohol consumption on Brf1 (TFIIIB-related factor 1) expression and RNA Pol III gene (RNA polymerase III-dependent gene) transcription, which are responsible for protein synthesis and tightly linked to cell proliferation, cell transformation, and tumor development. Emerging evidences have indicated that alcohol induces deregulation of Brf1 and Pol III genes to cause the alterations of cell phenotypes and tumor formation. In this paper, we summarize the progresses regarding alcohol-caused increase in the expression of Brf1 and Pol III genes and analysis of its molecular mechanism of breast cancer. As the earlier and accurate diagnosis approach of breast cancer is not available yet, exploring the molecular mechanism and identifying the biomarker of alcohol-associated breast cancer are especially important. Recent studies have demonstrated that Brf1 is overexpressed in most ER+ (estrogen receptor positive) cases of breast cancer and the change in cellular levels of Brf1 reflects the therapeutic efficacy and prognosis of this disease. It suggests that Brf1 may be a potential diagnosis biomarker and a therapeutic target of alcohol-associated breast cancer.