The purpose of the study was to investigate the
biological risk of asbestiform
antigorite, which is a fibrous variety of
antigorite, one of the natural
mineral fibres of the
serpentine group to which
asbestos chrysotile belongs. Asbestiform
antigorite is very abundant and commonly found associated with
asbestos chrysotile in serpentinites, a kind of rock outcropping present in many geographical locations worldwide. In this study we evaluated the morphological, immunohistochemical and functional effects of
antigorite fibres in alveolar epithelial
cancer cells (A549), a standardized human cell line currently used as a model to study cytotoxicity induced by pharmacological agents. The
antigorite fibres were identified and characterized morphologically and chemically by X-ray
powder diffractometry, transmission and scanning electron microscopy, both with annexed energy dispersive spectrometry. The effects of 50 microg/ml of
antigorite in A549 lung cells treated at 24 and 48 h resulted in increased synthesis of
VEGF, Cdc42 and
beta-catenin that represent potential risks for
cancer development.
Phalloidin labelling showed an irregular distribution of filamentous actin resulting from
antigorite contact. Our studies indicate potential cellular toxicity of
antigorite in vivo, providing the opportunity to elucidate the effect of
asbestos on
cancer induction and possible modes of
therapy.