Early induction of genetic instability and apoptosis by arsenic in cultured Chinese hamster cells

In order to assess at what time from the beginning of exposure inorganic arsenic can give rise to genetic instability and trigger apoptosis, V79-C13 Chinese hamster cells were treated with 10 microM sodium arsenite for 24 h. Under these conditions, cell survival was >70% and cells showed neither an increase in chromosome aberration frequency nor a delay in cell cycle progression. Investigations, which were carried out every 6 h during the treatment, revealed an early appearance of genetically unstable cells, namely micronucleated, multinucleated and mononucleated 'giant' cells, as well as apoptotic cells. Indirect immunostaining using anti-beta-tubulin antibody showed severe alterations in …