Oxidative stress (OS) refers to the imbalance between the generation of reactive oxygen species (ROS) and the ability to scavenge these ROS by endogenous antioxidant systems, where ROS overwhelms the antioxidant capacity. Excessive presence of ROS results in irreversible damage to cell membranes, DNA, and other cellular structures by oxidizing lipids, proteins, and nucleic acids. Oxidative stress plays a crucial role in the pathogenesis of cardiovascular diseases related to hypoxia, cardiotoxicity and ischemia–reperfusion. Here, we describe the participation of OS in the pathophysiology of cardiovascular conditions such as myocardial infarction, anthracycline cardiotoxicity and congenital heart disease. This review focuses on the different clinical events where redox factors and OS are related to cardiovascular pathophysiology, giving to support for novel pharmacological therapies such as omega 3 fatty acids, non-selective betablockers and microRNAs.

Gastric cancer is the third leading cause of cancer mortality worldwide. Unfortunately, most gastric cancer cases are diagnosed in an advanced, non-curable stage and with a limited response to chemotherapy. Drug resistance is one of the most important causes of therapy failure in gastric cancer patients. Although the mechanisms of drug resistance have been broadly studied, the regulation of these mechanisms has not been completely understood. Accumulating evidence has recently highlighted the role of microRNAs in the development and maintenance of drug resistance due to their regulatory features in specific genes involved in the chemoresistant phenotype of malignancies, including gastric cancer. This review summarizes the current knowledge about the miRNAs’ characteristics, their regulation of the genes involved in chemoresistance and their potential as targeted therapies for personalized treatment in resistant gastric cancer.

Gallbladder cancer (GBC) is a highly fatal disease with poor prognosis and few therapeutic alternatives. The molecular mechanisms involved in the pathogenesis of GBC remain poorly understood. The vascular endothelial growth factor A (VEGF-A) is a potent proangiogenic agent involved in the carcinogenesis of many human tumors and is an attractive target for cancer therapy. We characterized VEGF-A expression in advanced GBC and its relation to clinicopathologic features. VEGF-A expression was examined by immunohistochemistry in tissue microarrays containing 224 advanced gallbladder carcinomas and 39 chronic cholecystitis. The cases were classified as low or high expression to evaluate the association of VEGF-A expression level with clinicopathologic variables. The Kaplan-Meier method was used to estimate survival as a function of time, and survival differences were analyzed by the log-rank test. High expression of VEGF-A was observed in 81% (183/224) of tumors and 5.1% (2/39) of chronic cholecystitis (P<0.0001). The VEGF-A expression had a significant relationship with histologic grade and TNM stage (P<0.05). Moreover, 5-year survival analysis indicated that high expression of VEGF-A is associated with a poor prognosis in patients with advanced GBC (P=0.0116). Our results indicate that VEGF-A is highly expressed in GBC and correlates with poor prognosis, suggesting that VEGF-A expression could be used as a biomarker for predicting malignant behavior and for identifying a subset of patients who may benefit from anti-VEGF-A therapies.

Reprimo (RPRM), a highly glycosylated protein, is a new downstream effector of p53-induced cell cycle arrest at the G2/M checkpoint, and a putative tumor suppressor gene frequently silenced via methylation of its promoter region in several malignances. The aim of this study was to characterize the epigenetic inactivation and its biological function in BC cell lines. The correlation between RPRM methylation and loss of mRNA expression was assessed in six breast cancer cell lines by methylation specific PCR (MSP), 5′-Aza-2′-deoxycytidine treatment and RT-PCR assays. MDA-MB-231 cells were chosen to investigate the phenotypic effect of RPRM in cell proliferation, cell cycle, cell death, cell migration and invasion. In the cancer methylome system (CMS) (web-based system for visualizing and analyzing genome-wide methylation data of human cancers), the CpG island region of RPRM (1.1 kb) was hypermethylated in breast cancer compared to normal breast tissue; more interesting still was that ERα(+) tumors showed higher methylation intensity than ERα(−). Downregulation of RPRM mRNA by methylation was confirmed in MDA-MB-231 and BT-20 cell lines. In addition, overexpression of RPRM in MDA-MB-231 cells resulted in decreased rates of cell migration, wound healing and invasion in vitro. However, RPRM overexpression did not alter cell viability, phosphatidylserine (PS) translocation or G2/M cell cycle transition. Taken together, these data suggest that RPRM is involved in decreased cell migration and invasion in vitro, acting as a potential tumor suppressor gene in the MDA-MB-231 cell line.