[Comparative analysis of differentiating and apoptogenic effects of cytidine, thymidine, and guanosine on cells of human erythromyeloleukemic cell line K562].

The antiproliferative, differentiating and apoptogenic effects of purinic (cytidine and thymidine) and pyrimidinic (guanosine) nucleosides on K562 cells were investigated. Induction of erythroid differentiation (haemoglobin synthesis) in cancer cells was observed after 2 and 4 days incubation with 2 mM thymidine and 1 mM guanosine. Increase of haemoglobin synthesis in K 562 cells incubated with 2 mM cytidine was detected at 4 day. Analysis of the DNA-degrading effect (induction of apoptosis) of the reagents used on K 562 cells by fluorescent dyes and modulation activity of caspase 9 and also caspases 3,7,10 is induced with thymidine and guanosine but not with cytidine.