【摘要】 目的:研究干扰素-α(IFN-α)联合高三尖杉酯碱(HHT)对K562细胞端粒酶逆转录酶及端粒酶的作用,并探讨其与细胞凋亡的关系。方法:IFN-α、HHT以及两药联合作用K562细胞后用MTT法检测细胞增殖,吉姆萨-瑞氏染色观察细胞形态,PI-AnnexinVFITC双染色、流式细胞仪检测细胞凋亡,Krupp改良的荧光素标记的端粒重复扩增方法(TRAP)检测K562细胞端粒酶活性,RT-PCR方法检测hTERTmRNA表达变化。结果:5×106U.L-1IFN-α分别联合5-40μg.L-1HHT诱导K562细胞凋亡从而抑制其生长,单用HHT时IC50为27.35μg.L-1,联用5×106U.L-1IFN-α后IC50降为18.72μg.L-1;IFN-α与HHT联用明显下调hTERTmRNA表达并抑制K562细胞的端粒酶活性。结论:IFN-α联合HHT可以诱导细胞凋亡,这可能与下调细胞hTERTmRNA的表达水平,抑制端粒酶活性有关。两药联合作用强于单独用药,提示临床IFN-α联合HHT治疗慢性髓细胞白血病(CML)可能比单用HHT效果更好。更多还原

【Abstract】 AIM:To examine the synergistic action of interferon-α(IFN-α)and homoharringtonine(HHT)on the human telomerase reverse transcriptase(hTERT)mRNA expression and telomerase activity in K562 cells,and to explore their relationship with apoptosis.METHODS:The growth of cell line K562 induced by agents was assayed by MTT,morphological observation was assayed by Wright-Giemsa,apoptosis was assayed by flow cytometry(FCM)according to the positive PI-Annexin V FITC and Krupp modify TRAP assay was used to test K562 telomerase activity and RT-PCR to hTERT mRNA expression.RESULTS:5×106 U/L IFN-α in combination with 5-40 μg/L HHT respectively inhibited K562 growth through inducing cellular apoptosis,IC_ 50 was 27.35 μg/L incubated by HHT only and IC_ 50 of HHT decreased to 18.72 μg/L while in combination with 5×106 U/L.The level of hTERT mRNA expression in K562 cells was declined and the activity of K562 telomerase was inhibited by IFN-α in combination with HHT.CONCLUSION:The simultaneous IFN-α and HHT inducing K562 apoptosis may be related to suppressing the hTERT mRNA expressing level and inhibiting the activity of telomerase.The function of simultaneous two agents was higher than only one agent applying,suggestting that the clinic acurative effect may be better for CML patients with IFN-α and HHT simultaneously than IFN-α alone.更多还原