甘草提取物体外选择性诱导几种人肿瘤细胞凋亡

Glycyrrhiza uralensis Fisch Extract Selectively Induces Apoptosis in Several Human Cancer Cell Lines in Vitro

目的:从体外诱导人肿瘤细胞凋亡的角度研究传统中药甘草的抗癌作用。方法:采用Hoechst33342染色观察染色体凝聚和流式细胞仪检测凋亡峰两种方法检测细胞凋亡。分别以Fluo3和Rh123为荧光探针,用流式细胞仪测定胞内游离钙和线粒体膜电位△Ψm变化。用免疫组化方法检测原癌基因cfos、cjun与cmyc表达量的变化。结果:甘草选择性诱导胃癌MGC803、肝癌HepG2、肺癌NSCLC与宫颈癌Hela等几种人肿瘤细胞凋亡。甘草处理的MGC803、HepG2和NSCLC细胞均观察到胞内游离钙升高和△Ψm的下降。有趣的是,甘草不能诱导胃癌BGC823细胞凋亡,但其胞内钙和△Ψm与凋亡细胞株具有同样变化规律。原癌基因cfos、cjun与cmyc的蛋白产物在甘草处理的MGC803细胞中明显上调。结论:甘草抗癌活性与诱导肿瘤细胞凋亡有关,胞内钙升高、△Ψm下降和cfos、cjun与cmyc蛋白表达上调参与甘草诱导肿瘤细胞凋亡的调控。

Objective: To determine the anti tumor activity of glycyrrhiza uralensis Fisch in terms of apoptosis induction. Methods: Apoptosis was detected by fluorescence microscope and flow cytometry. Intracellular free Ca2+ and mitochondrial transmembrane potential (△Ψm) were measured by fluorescent probes Fluo 3 and Rh123, respectively. The expression of three proto oncogenes, c myc, c jun, and c fos,was examined by immunohistochemistry. Results: Glycyrrhiza uralensis Fisch extract selectively induced apoptosis in several human cancer cell lines, including MGC 803, HepG2, NSCLC, and Hela. Increase of intracellular free Ca2+ and decrease of △Ψm were observed in the apoptosis of MGC 803, HepG2, and NSCLC. Interestingly, glycyrrhiza uralensis Fisch extract couldn′t induce apoptosis in BGC-823, however, the changes of intracellular free Ca2+ and △Ψm were similar to that of apoptotic cell lines. The expression of c myc, c jun, and c fos in MGC 803 was elevated after the treatment. Conclusions: The anti tumor acitivity of glycyrrhiza uralensis Fisch is related to its ability of apoptosis induction in tumor cells. Increase of intracellular free Ca2+, decrease of △Ψm and the up regulation of c fos, c jun, and c myc protein expression take part in the regulation of apoptosis induced by the extract of glycyrrhiza uralensis Fisch.