CHROMOSOMAL-ABERRATIONS IN-VITRO INDUCED BY ANEUGENS

Various aneugens were reported to induce structural chromosomal aberra tions beside their influence on cell division and their aneugenic pote ntial To assess, whether a relationship between disturbance of cell di vision and clastogenic potential exists, CHO cells were treated with t he well-known aneugens colcemid, colchicine and vincristine and invest igated for the induction of structural chromosomal aberrations, polypl oid cells and alterations in mitotic index. At low and intermediate co ncentrations, all compounds induced polyploidy and an increase in mito tic index, but no structural aberrations at all. However, at high conc entrations, colcemid and colchicine both induced numerous structural c hromosomal aberrations in diploid cells. Colchicine was also clastogen ic in tetraploid cells. Vincristine did not induce structural chromoso mal aberrations in diploid cells, but in tetraploid cells. The clastog enic effects showed a clear-cut threshold with all three compounds. Fu rthermore, it was found that the tetraploid condition in CHO cells is generally accompanied by an increase in structural chromosomal aberrat ions, in vehicle controls as well as in cultures treated with the aneu gens. Nevertheless, this study demonstrates that for the three aneugen ic compounds tested, no direct relationship between compound induced d isturbance of cell cycle and compound induced structural chromosomal a berration incidence exists. (C) 1997 Elsevier Science B.V.