[Effects of arsenic trioxide, ginseng saponin and beta-elemene on telomere-telomerase system in K562 cell line].

The aim was to explore the modulating and inhibiting effects of arsenic trioxide, ginseng saponin and beta-elemene on telomere length and telomerase activity in K562 cell line, and to study their anti-tumor mechanism and seek new method of therapy for acute leukemia. Human erythroleukemia cell line K562 was co-cultured with arsenic trioxide, ginseng saponin, beta-elemene separately, cells were collected after 24, 48 and 72 hours for further detecting. Telomere length and telomerase activity were detected by the methods of Southern-blot and PCR-ELISA respectively. The effects of these drugs on telomere length and telomerase activity were observed at different concentrations and length of time. The results showed that (1) telomerase activity of K562 cells decreased after co-cultured with arsenic trioxide, ginseng saponin and beta-elemene. The inhibiting effects depended on drug concentrations and length of time. When co-cultured at proper concentration and period of time, telomerase activity could be inhibited; (2) viability of K562 cells decreased after co-cultured with arsenic trioxide, ginseng saponin and beta-elemene, the inhibiting effect depends on drug concentrations and length of time; (3) after co-cultured with arsenic trioxide, ginseng saponin, and beta-elemene for 72 hours, telomere length of K562 cell line prolonged a little. It is concluded that (1) arsenic trioxide, ginseng saponin and beta-elemene can inhibit telomerase activity in K562 cell line, the suppression of telomerase activity may be one of the mechanisms of anti-tumor effect; (2) arsenic trioxide, ginseng saponin and beta-elemene can inhibit the growth of K562 cell line, the inhibiting effect depends on concentration and time; (3) when telomerase activity was suppressed, the telomere length prolonged a little, indicating that in K562 cell line may exist another mechanism to regulate telomere length, except telomerase activation.