[Alterations of telomerase activity and apoptosis induced by 2-methoxyestradiol in human myelodysplastic syndrome cell line MUTZ-1].

Objective: To study the effect of 2-methoxyestradiol(2-ME) on telomerase activity expression and apoptosis in human myelodysplastic syndrome cells line MUTZ-1.
Methods: MUTZ-1 cells were incubated with different concentrations of 2-ME, apoptosis rate and cell cycle were measured by flow cytometry (FCM). Telomerase activity in MUTZ-1 cells was examined by telomeric repeat amplification protocol-Enzyme linked immunosorbent assay (TRAP-ELISA).
Results: The FCM analysis showed that cells in G0/G1 phase and S phase were decreased, while in G2/M phase increased after exposed to 1,2 and 4 micromol/L of 2-ME for 12 hours (P < 0.05). 1 and 2 micromol/L of 2-ME had no notable effect on MUTZ-1 cells as compared with the control group (P > 0. 05). Cells incubated with 1, 2 and 4 micromol/L of 2-ME for 36 hours were induced apoptosis, the percentage of apoptosis was between (12.87 +/- 0.86)% and (21.82 +/- 1.71)% with a dose- and time- dependent manner. Telomerase activity was significantly inhibited in these concentration and negatively correlated with cell number in G2/M phase (r = -0.979, P = 0.021) and increased apoptosis (r = -0.970, P = 0.030 ), respectively. Moreover, the inhibition effect of telomerase activity was enhanced in a dose- and time- dependent manner.
Conclusions: 2-ME-induced apoptosis and inhibition of telomerase activity provide a possible mechanism for explaining the 2-ME's anticancer activity.