昆明山海棠根部水提液诱导HL-60细胞凋亡及对c-Myc基因表达的调控

目的 研究昆明山海棠Tripterygium hypoglaucum(Celastraceae)(THH)根部水提液对早幼粒白血病HL-60细胞凋亡的诱导作用及机制。方法 通过特征性的形态学观察，Annexin—V标记，以及流式细胞仪检测中次G1峰的形成确定THH的诱导细胞凋亡作用；应用Western Blotting研究THH对c—Myc蛋白表达的影响。结果 THH根部水提液可诱导早幼粒白血病HL-60细胞凋亡。在浓度高于18μg／mL时，THH对HL-60细胞的诱导凋亡作用呈现浓度与时间的相关性。在THH处理2～4h后，癌基因蛋白c—Myc表达降低99％以上。结论 THH抑制了c—Myc蛋白的翻译或后翻译过程，从而降低了c—Myc在细胞周期运转中的作用，导致大量细胞凋亡．

Apoptosis in HL-60 cells induced and c-Myc expression down-regulated by root aqueous extract from Tripterygium hypoglaucum

Object To investigate the effects of the root aqueous extract of Tripterygium hypoglaucum(Levl.) Hutch (Celastraceae) (THH) on human promyelocytic leukemia HL-60 cells and its mechanism.Methods Cell growth and toxicity assays, flow cytometry, confocal fluorescence microscopy and Annexin-V labeling, and Western Blotting Assay were used. Results THH causedmorphological changes hypodiploid sub-G1 cell accumulation and induced dose- and time-dependent apoptosis in HL-60 cells at concentrations above 18 μg/mL. Western Blotting analysis showed a more than 99% decrease of the nuclear oncoprotein c-Myc after 2-4 h of THH treatment. Conclusion THH decreases c-Myc protein expression,leading to the deactivation of cell cycle progression pathways and an accumulation of hypodiploid sub-G1cells thateventually enter apoptosis.