臭灵丹中黄酮类化合物对人喉癌细胞Hep-2凋亡的影响及机制

Effect of 3,5-hydroxy-6,7,3',4'-tetramethoxyflavone isolated from Laggera pterodonta on apoptosis of Hep-2 cells in vitro

目的:探讨中药臭灵丹中黄酮类化合物诱导人喉癌细胞Hep-2凋亡的机制。方法:MTT法检测分离自臭灵丹的黄酮类化合物3,5-二羟基-6,7,3',4'-四甲氧基黄酮(HTMF)对2种正常细胞的毒性和对3种肿瘤细胞株的增殖抑制作用;采用流式细胞仪检测化合物对Hep-2细胞凋亡率的影响;Western blotting法检测凋亡蛋白caspase-3和caspase-9的变化。结果:HTMF显著抑制Hep-2细胞的增殖并呈浓度、时间双重依赖性关系,但对正常细胞Vero和EVC304的毒性较小,对A549和HepG2细胞抑制作用小。流式细胞仪检测结果显示HTMF对Hep-2细胞有促凋亡作用并呈明显的量效、时效关系。Western blotting结果显示HTMF可诱导Hep-2细胞中caspase-3和caspase-9蛋白的活化,并呈时间依赖性关系。结论:HTMF对人喉癌细胞Hep-2的生长有显著的抑制作用,其机制可能通过激活caspase-9进而活化caspase-3诱导Hep-2细胞凋亡。

AIM： To investigate the effect of 3,5-hydroxy-6,7,3＇ ,4＇ - tetramethoxyflavone （HTMF） iso- lated from Laggera pterodonta on Hep - 2 cell apoptosis and the underlying mechanism. METHODS ： The MTT assay was used to observe the cytotoxicity of HTMF to the normal cells and the inhibitory effect of HTMF on the proliferation of tumor cells. The apoptosis was determined by flow cytometry. Western blotting was used to detect the expression of caspase - 3 and caspase -9. RESULTS： HTMF significantly inhibited the growth of Hep -2 cells in dose and time dependent manners. HTMF exhibited weak cytotoxicity to the two normal cell lines Vero and EVC304, while showed low effect of anti - proliferation on HepG2 cells and A549 ceils. The increase in apoptosis of Hep -2 cells by HTMF was observed with dose and time dependent manners. Western blotting showed that HTMF time dependently increased the expression of caspase - 3 and caspase -9 in Hep -2 ceils. CONCLUSION： HTMF has high inhibitory effect on the proliferation of Hep -2 cells by induction of apoptosis in the tumor cells through caspase -9 and caspase -3 activation. However, the cytotoxicity of HTMF to the normal cells is low.