高三尖杉酯碱诱导HL-60细胞人端粒酶逆转录酶mRNA的变化

Effect of Homoharringtonine on Expression of Human Telomerase Reverse Transcriptase mRNA in HL-60 Cells

为了探讨高三尖杉酯碱 (homoharringtonine ,HHT)抑制HL 6 0细胞端粒酶活性的机制及意义 ,采用半定量RT PCR和PCR ELISA法检测HHT作用后的HL 6 0细胞人端粒酶逆转录酶 (hTERT)mRNA表达和端粒酶活性的变化 ,用TUNEL法检测HL 6 0细胞的凋亡率。结果发现 :与空白对照相比 ,0 .0 0 5 - 0 .0 3μg/mlHHT作用HL 6 0细胞 12小时 ,hTERTmRNA表达无明显变化 ,随HHT浓度增加至 0 .0 4 - 0 .0 5 μg/ml,hTERTmRNA表达明显下降至检测不出。与 0小时相比 ,0 .0 2 μg/mlHHT作用 6 - 18小时后 ,HL 6 0细胞hTERTmRNA表达无明显变化 ,2 4小时后hTERTmRNA表达明显减少 ,至 30小时未能检出hTERTmRNA表达。HL 6 0细胞端粒酶活性的抑制与hTERTmRNA的表达下降趋势基本一致。随HL 6 0细胞hTERTmRNA的表达下降和端粒酶活性的抑制 ,其凋亡率明显增加。结论 :HHT能抑制HL 6 0细胞hTERTmRNA的转录 。

To investigate the mechanism and its significance of the depression of telomerase activity in HL 60 cells exposed to homoharringtonine(HHT), the semi quntitative RT PCR and PCR ELISA were used to detect the expression of hTERT mRNA and telomerase activity in HL 60 cells, the apoptotic rate of HL 60 cells was assayed with TUNEL. The results indicated that compared with the control, the level of hTERT mRNA synthesis in HL 60 cells treated with HHT at 0.005-0.03 μg/ml for 12 hours did not change significantly, but it reduced obviously at 0.04 μg/ml and was undetectable at 0.05 μg/ml. When HL 60 cells incubated with HHT at 0.02 μg/ml for various hours, the expression of hTERT mRNA did not decrease after 6-18 hours and reduced significantly after 24 hours and was undetectable at 30 hours. The tendency for suppression of telomerase activity was consistent with decrease of the expression of hTERT mRNA in HHT treated HL 60 cells. The apoptotic rate of HL 60 cells was apparently increased with the depression of hTERT mRNA and telomerase activity. In conclusion, the transcription of hTERT mRNA in HL 60 cells can be inhibited by HHT. The relationship between regulation of hTERT mRNA expression and HHT induced apoptosis is worth investigating furtherly.