Cytotoxicity and genotoxicity effects of arsenic trioxide on SQ20B human laryngeal carcinoma cells

Abstract This study investigates the cytotoxicity and the genotoxicity induced by arsenic trioxide As 2 O 3 in human laryngeal SQ20B carcinoma cell line. SQ20B cells were exposed to graded concentrations of arsenic trioxide (2 and 5 μM) for 48 h. Comet assay and γ-H2AX foci formation were used for measuring DNA damages, flow cytometry was used to identify cell cycle alterations and apoptosis, while cell morphology was visualized using transmission electron microscopy. The results show a dose-dependent induction of DNA damages and double strand breaks, alterations in cell cycle and morphologic alterations of cells. These results prove that As 2 O 3 is highly cytotoxic and genotoxic at the micromolar range ina human laryngeal carcinoma cell line.