Genetic and epi-genetic alterations of the PTEN gene: key in the relationship between type 2 diabetes and cancer

Cancer pathogenesis has been associated with genetic and epigenetic alterations that may lead to the inactivation or decrease of tumor-suppressor genes, such as the PTEN gene. In particular, alterations in the PI3K/PTEN signaling pathways are related to abnormalities associated with diabetes, metabolic syndrome, obesity and cardiovascular diseases. The aim of the study was to evaluate whether the expression levels of the PTEN gene, the 32-bp deletion in the PTEN gene, and the methylation in the PTEN promoter are associated with Type 2 Diabetes Mellitus(T2DM) and cancer development. Peripheral blood samples were obtained from a total of 70 patients of both sexes: 40 patients with T2DM and 30 patients with T2DM and cancer(T2DM+C). In this a novel report that assesses the upregulation of PTEN in T2DM, we observed that PTEN expression is higher in T2DM patients than in healthy individuals and markedly lower in T2DM patients with cancer than in T2DM patients without cancer. Hypermethylation of the PTEN promoter is more frequent in T2DM patients with cancer. Genetic and epigenetic alterations of the PTEN gene may be a key in the relationship between T2DM and cancer. PTEN expression may serve as a potential candidate biomarker for cancer development in T2DM patients.