硫化砷诱导HL-60细胞凋亡中端粒酶活性和hTERT mRNA表达的改变

Changes of telomerase activity and hTERT mRNA expression in the process of apoptosis of HL-60 cells in- duced by arsenic sulfide

目的:探讨硫化砷在诱导急性非淋巴细胞白血病(APL)细胞株HL-60凋亡的同时,对端粒酶活性的影响及作用机制。方法:采用PCR-ELISA法测定端粒酶活性;半定量RT-PCR检测hTERT mRNA的表达;流式细胞仪分析细胞周期、细胞 凋亡及CD11b表达。结果:用0.3-0.6 mg/L的硫化砷作用72 h,不能诱导HL-60细胞凋亡,将剂量增至1.5-3.0 mg/L时,凋亡细胞的比率逐渐增高,同时伴随HL-60细胞端粒酶活性和hTERT mRNA表达受抑。随着硫化砷浓度的增高,HL-60细胞在G2/M期的比率渐增高。3.0 mg/L的硫化砷作用72 h,HL-60细胞CD11b的表达由1.27％升至6.07％。结论:硫化砷在诱导HL-60细胞凋亡的同时,下调其端粒酶活性。G2/M期细胞比率的增高可能与端粒酶活性降低相关。高浓度硫化砷72 h可轻度诱导HL-60细胞分化。

AIM: To explore the effect of arsenic sulfide on telomerase activity of HL-60 cells. METHODS: Telomerase activity was determined by PCR-ELISA. The expression of hTERT-mR-NA was analyzed by semi-quantitative RT-PCR. Flow cy-tometry was used to analyze the cell cycle, apoptosis and CDllb expression of HL-60 cells. RESULTS: Treament of HL-60 cells with 0.3 -0.6 mg/L arsenic sulfide for 72 h did not induce apoptosis of the cells, while 1.5-3.0 mg/L did. Furthermore, 1.5 -3.0 mg/L arsenic sulfide inhibited the telomerase activity and hTERT-mRNA expression in HL-60 cells. Proportion of the cells in Q2/M phase was increased when being treated with arsenic sulfide. 3. 0 mg/L arsenic sulfide upregulated CDllb expression in HL-60 cells from 1.0% to 6. 8%. CONCLUSION: Arsenic sulfide can inhibit telomerase activity. The increase of proportion of HL-60 cells in G2/M phase may be related to the reduction of telomerase activity. High dosage of arsenic sulfide can slightly induce differentiation of HL-60 cells.