The perchloroethylene-induced toxicity in dry cleaning workers lymphocytes through induction of oxidative stress.

Evaluation of the compounds and metabolites, and studying their side effects in the workplace is essential. This study was designed to evaluate the exposure of dry  cleaning workers to perchloroethylene (PEC), and its liver and kidney damage, and oxidative stress in B-lymphocytes isolated from the workers. Blood samples were evaluated for liver (alanine transaminase [ALT] and aspartate transaminase [AST]) and kidney (BUN and creatinine) markers. For measurement of PEC, exhaled, personal, and ambient air samples were collected and analyzed gas chromatography (GC-FID) through the NIOSH 1003 and 3704 methods. Also, the parameters of oxidative stress including the level of reactive oxygen species (ROS), glutathione (GSH), oxidized glutathione (GSSG), and lipid peroxidation (LPO) in B-lymphocytes were evaluated. The results showed that the levels of liver enzymes ALT and AST in dry cleaning workers are higher than in the control group. The personal exposure levels and exhaled air concentration of PEC in dry cleaning workers were above the recommended national occupational exposure limits (OELs) and the biological exposure index (BEI). The levels of ROS, LPO, and GSSG in B-lymphocytes from the dry cleaning workers are higher than the control group, and the levels of GSH in dry cleaning workers are lower. The results suggested that exposure of dry cleaning workers to PEC could be associated with liver damage and oxidative damage in B-lymphocytes.

Epithelial-to-mesenchymal transition in thyroid cancer: a comprehensive review.

The Metastatic progression of solid tumors, such as thyroid cancer is a complex process which involves various factors. Current understanding on the role of epithelial-mesenchymal transition (EMT) in thyroid carcinomas suggests that EMT is implicated in the progression from follicular thyroid cancer (FTC) and papillary thyroid cancer (PTC) to poorly differentiated thyroid carcinoma (PDTC) and anaplastic thyroid cancer (ATC). According to the literature, the initiation of the EMT program in thyroid epithelial cells elevates the number of stem cells, which contribute to recurrent and metastatic diseases. The EMT process is orchestrated by a complex network of transcription factors, growth factors, signaling cascades, epigenetic modulations, and the tumor milieu. These factors have been shown to be dysregulated in thyroid carcinomas. Therefore, molecular interferences restoring the expression of tumor suppressors, or thwarting overexpressed oncogenes is a hopeful therapeutic method to improve the treatment of progressive diseases. In this review, we summarize the recent findings on EMT in thyroid cancer focusing on the main role-players and regulators of this process in thyroid tumors.