原肌球蛋白、波形纤维蛋白和热休克蛋白70在肝癌转移亚细胞中表达上调

建立并应用人H74 0 2肝癌细胞SCID鼠肿瘤转移模型 ,从转移肺组织经原代细胞培养 ,筛选并建立转移亚细胞系M H74 0 2 ,进而运用蛋白质组学技术筛选肿瘤转移相关蛋白 .通过二维电泳技术检测 ,比较M H74 0 2细胞和亲本H74 0 2细胞的总蛋白 ,从多个差异蛋白质点中选择出 3个在M H74 0 2细胞中表达明显上调的蛋白质点进行ESI QUAD TOF质谱分析 ,并在MSDB公共蛋白数据库中进行同源比较和分析鉴定 .初步确定这 3个蛋白质分别为原肌球蛋白 (tropomyosin) ,波形纤维蛋白 (vimentin)和热休克蛋白 70 (heatshock 70protein ,HSP70 ) .这些蛋白质参与细胞骨架构成、蛋白质折叠和蛋白质相互作用等许多正常生理活动 ,并有报道原肌球蛋白和波形纤维蛋白与肿瘤转移有关 .利用蛋白质组学方法发现 ,在肝癌转移亚细胞M H74 0 2中 ,原肌球蛋白、波形纤维蛋白和热休克蛋白 70表达明显上调 ,进一步揭示它们在肿瘤转移中具有重要的作用 .

Proteomics Analysis of Differentially Expressed Tropomyosin,Vimentin and HSP 70 in Highly Metastatic Sub-line of Human Hepatoma Cells

Metastasis is the most insidious incidence of cancers.However,little is known about the molecular mechanism of tumor metastasis.A highly metastatic sub-line of H7402 hepatoma cells(termed M-H7402) was developed through screening from the lung tissue of severe combined immunodeficiency(SCID) mice injected with H7402 cells by primary cell culture,M-H7402 cell line was selected as an experimental model.Two-dimensional gel electrophoresis and mass spectrometry are combined to approach the protein profiles associated with tumor metastasis between H7402 and M-H7402 cell lines.Image analysis of Coomassie brilliant blue stained two-dimensional gels revealed that three protein spots showed significantly quantities variation.These candidate proteins were detected by ESI-QUAD-TOF mass spectrometer analysis,and searched in a publicly available MSDB database using peptide mass fingerprinting (PMF).The results showed that they were tropomyosin,vimentin and heat shock protein 70(HSP70),respectively.It was reported that these proteins were involved in the normal physiological activities,such as composing cytoskeleton,protein folding and protein interactinon,etc.Recent study demonstrated that tropomyosin is an essential filament protein and vimentin expression coincides with cellular growth and cell cycle progression as well;while certain tumor cell lines express HSP-70 on cell surface.The up-regulation of tropomyosin,vimentin and heat shock protein 70 were found in M-H7402 cells,suggesting that the proteins were involved in tumor metastasis.