Multinucleation and pro-inflammatory cytokine release promoted by fibrous fluoro-edenite in lung epithelial A549 cells

Toxicology In Vitro. 2006 Feb 8; [Epub ahead of print]. Received 9 June 2005;  accepted 30 December 2005.  Available online 9 February 2006. [Link]

S. Travaglionea, 1, B.M. Brunib, 1, L. Falzanoa, P. Filippinib, A. Fabbria, L. Paolettib and C. Fiorentinia

aDepartment of Drug Research and Evaluation, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161 Rome, Italy
bDepartment of Technology and Health, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161 Rome, Italy


An unusual cluster of malignant mesothelioma was evidenced in Biancavilla, a Sicily village where no inhabitant had been significantly and professionally exposed to asbestos. Mineralogical and environmental studies led to the identification of a new prismatic amphibole, named fluoro-edenite. We previously reported, by using the human lung epithelial A549 cells, that prismatic fluoro-edenite was unable to induce changes that could be somehow related to cellular transformation, and this was in accordance with studies carried out in vivo. More recently, a fibrous amphibole with a composition very similar to that of prismatic fluoro-edenite, was identified in Biancavilla. This fibrous fluoro-edenite was shown to induce mesothelioma in rats. In keeping with this effect in vivo, in the present work we observed multinucleation and spreading, common features of transformed cells, as well as pro-inflammatory cytokine release in A549 cells. Such cell changes occurred without interfering with the passage of the resulting multinucleated cells through the cell cycle and without condemning cells to death. Hence, in lung epithelial cells, fibrous fluoro-edenite behaved similarly to the unrelated asbestos type crocidolite, whose connection with severe inflammation and cancer of the lung is renowned.

Keywords: Fibrous fluoro-edenite; Crocidolite; Epithelial cells; Multinucleation; Inflammatory cytokines