Effects of triphenyltin on growth and viability of K562 leukemia cells

The effects of triphenyltin on growth and viability of K562 human leukemia cells were examined using a flow cytometer with fluorescent dyes, ethidium bromide, fluo-3-AM, and propidium iodide. Triphenyltin at concentrations ra nging from 30 nM to 1 mu M inhibited the growth of K562 cells in a dose-dep endent manner when the cells were incubated with triphenyltin at respective concentrations for 72 h. Triphenyltin at 100 nM slowed the rate of growth without affecting the viability. Triphenyltin at 300 nM or higher greatly d ecreased the viability of K562 cells. Triphenyltin at 300 nM increased the concentration of intracellular Ca2+ and induced cell cycle arrest in G2/M p hase and apoptosis in K562 cells. The concentration of triphenyltin inducin g 50% inhibition of growth of K562 cells was lower than those of cisplatin, diphenyltin, monophenyltin, triethyltin and trimethyltin. However, tributy ltin was equally toxic. Results suggest that there are several types of mec hanisms for the inhibitory action of triphenyltin on the growth of K562 cel ls, being dependent on its concentration. (C) 1998 Elsevier Science B.V. Al l rights reserved.