The DNA methylome of inflammatory bowel disease (IBD) reflects intrinsic and extrinsic factors in intestinal mucosal cells.

Abnormal DNA methylation has been described in human inflammatory conditions of the gastrointestinal tract, such as inflammatory bowel disease (IBD). As other complex diseases, IBD results from the balance between genetic predisposition and environmental exposures. As such, DNA methylation may be the consequence (and potential effector) of both, genetic susceptibility variants and/or environmental signals such as cytokine exposure. We attempted to discern between these two non-excluding possibilities by performing a combined analysis of published DNA methylation data in intestinal mucosal cells of IBD and control samples. We identified abnormal DNA methylation at different levels: deviation from mean methylation signals at site and region levels, and differential variability. A fraction of such changes is associated with genetic polymorphisms linked to IBD susceptibility. In addition, by comparing with another intestinal inflammatory condition (i.e., coeliac disease) we propose that aberrant DNA methylation can also be the result of unspecific processes such as chronic inflammation. Our characterization suggests that IBD methylomes combine intrinsic and extrinsic responses in intestinal mucosal cells, and could point to knowledge-based biomarkers of IBD detection and progression.

Different Cell Cycle Modulation in SKOV-3 Ovarian Cancer Cell Line by Anti-HIV Drugs.

Antiretroviral drugs used for the treatment of human immunodeficiency virus (HIV) have proven to be effective even against cancer. Drawing from this background, the aim of our research project was to evaluate the effects of anti-HIV drugs that belong to the nucleoside and nucleotide reverse transcriptase inhibitor [NRTI; abacavir (ABC) and tenofovir (TDF)], nonnucleoside reverse transcriptase inhibitor [NNRTI; efavirenz (EFV) and etravirine (ETR)], and protease inhibitor [PI; darunavir (DRV)] categories on ovarian adenocarcinoma cell line SKOV-3. Using FACS analysis, we observed that treatment with NRTIs and NNRTIs showed a block in the G0/G1 phase. In particular, ETR displayed a relevant block in the progression of the G0/G1 phase of the cell cycle compared with the other examined drugs, and it also induced differentiation of SKOV-3 cells. In contrast, FACS analysis demonstrated that ABC and the PI inhibitor DRV showed no effect on the proliferation of cancer cells. DAPI (4',6-diamidino-2-phenylindole) staining demonstrated that cells treated with NNRTIs (EFV and ETR) presented more DNA damage compared with other treatments. Immunoblotting analysis demonstrated that TDF, EFV, and ETR were able to obtain a reduction in the expression of cyclin D1 and Rb hypophosphorylation, and an increase in p21 concentration. Finally, we observed that ETR also induced differentiation, as demonstrated by Western blot, with high levels of E-cadherin expression. Therefore, our study provides additional evidence supporting the in vitro cytotoxic effects of ETR and EFV. Furthermore, it promotes the hypothesis for their potential use as therapeutic agents in ovarian cancer.