肿瘤抑素19肽诱发人肿瘤细胞HepG2凋亡机制研究

Mechanism of apoptosis in HepG2 cells induced by tumstatin 19 peptide

目的研究肿瘤抑素19肽(T19肽)对人肝癌细胞HepG2的诱导凋亡作用并探讨其作用的分子机制,为临床联合应用抗肿瘤药物提供理论依据。方法采用亲和层析的方法提取T19肽,分离纯化后经Tricine-SDS-PAGE鉴定T19肽。MTT比色实验测定T19肽对肝癌细胞的半数抑制浓度。HE染色、AO/EB实验验证T19肽促进细胞凋亡的作用。流式细胞仪检测细胞线粒体膜电位的变化,Western blot检测细胞色素C(Cyt C)从线粒体到胞浆的易位情况。结果 T19肽对肝癌细胞HepG2有一定的抑制作用并呈剂量依赖的方式。T19肽降低了线粒体膜电位,引起Cyt C从线粒体释放到胞浆。结论 T19肽通过线粒体途径引起肝癌细胞HepG2凋亡。

Objective To study the effect of tumstatin 19 peptide（T19） on apoptosis of HepG2 cells and its molecular mechanism,to supply the theoretical evidence for the clinical application of combination therapy.Methods Recombinant peptide 19 was purified by affinity chromatograph and identified by Trincine-SDS-PAGE.MTT was used to assay the concentration of lethal dose 50（LD50）.Hematoxylin and eosin staining（HE staining）and AO/EB staining were used to evaluate the morphological changes during apoptosis.The changes of mitochondria membrane potential were detected by flow cytometry（FCM）.Translocation of cytochrome C（Cyt C） was assayed by Western blot.Results T19 peptide both inhibited the growth of HepG2 cells and 293 cells in a dose-dependent manner.T19 peptide made the mitochondrial potential loss and cytochrome C delivered from mitochondria to endochylema.Conclusion T19 peptide could induce tumor cell apoptosis through a mitochondrial pathway.