tremolite and Adenocarcinoma--Bronchiolo-Alveolar

Given the role of phosphoinositide-specific phospholipase C (PLC) isozymes in the control of cell growth and differentiation we were prompted to analyze the expression of some of these PLC in human bronchoalveolar carcinoma-derived alveolar epithelial A549 cells. The effects of several fluoro-edenite fibers were compared with those of tremolite, a member of the calcic amphibole group of asbestos that originates from Calabria (Italy), and crocidolite, that, due to its high toxicity, is one of the most studied asbestos amphiboles. Our data show an increased expression of both PLC beta1 and PLC gamma1 in A549 cells treated with asbestos-like fibers, hinting at a role of PLC signalling in those cancerous cells.

Topics: Adenocarcinoma, Bronchiolo-Alveolar; Asbestos, Amphibole; Asbestos, Crocidolite; Cell Line, Tumor; Enzyme Activation; Humans; Lung Neoplasms; Phosphatidylinositols; Phospholipase C beta; Phospholipase C delta; Second Messenger Systems

Diagnosis of asbestosis and bronchiolo-alveolar carcinoma was made in a 55-year-old Turkish woman who was a nonsmoker. She originated from and was living in an area with a high prevalence of environmental diseases attributed to tremolite asbestos. Mineralogic analysis of lung tissue revealed very high concentrations of asbestos bodies (1.64 x 10(6)/g of dry tissue) and tremolite fibers (173.7 x 10(6) of dry tissue). This case illustrates the following points: (1) In some areas, environmental exposure can lead to cumulated fiber retention comparable to occupational exposure and thus can represent a risk for lung fibrosis (asbestosis). (2) Lung cancer as a complication of environmental asbestosis also should be considered as a potential environmental disease.

Topics: Adenocarcinoma, Bronchiolo-Alveolar; Asbestos, Amphibole; Asbestosis; Environmental Exposure; Female; Humans; Lung Neoplasms; Middle Aged