视黄酸诱导人神经母细胞瘤SK-N-SH细胞分化过程中核基质蛋白组成的变化

在鉴定视黄酸(retinoic acid, RA)诱导人神经母细胞瘤SK-N-SH细胞分化的基础上,应用免疫细胞化学、选择性抽提和蛋白质组学分析技术,对SK-N-SH细胞诱导分化过程中核基质蛋白组成变化进行了系统研究.实验结果显示,经1 μmol/L RA处理后SK-N-SH细胞呈极性状,伸出较长的轴突样突起,胞体逐渐变小变圆.免疫细胞化学结果显示,处理后神经细胞特异表达的蛋白synaptophysin、NSE、MAP2的表达量都较对照组有明显增强.双向凝胶电泳分析显示,在RA诱导SK-N-SH细胞分化前后存在52个差异表达的核基质蛋白,经质谱分析,鉴定了其中的41个蛋白.蛋白印迹杂交进一步确证了诱导分化差异表达核基质蛋白中nucleophosmin和prohibitin等的表达变化.研究结果表明,1 μmol/L RA对SK-N-SH细胞具有显著的诱导分化作用,在SK-N-SH细胞分化过程中,其核基质蛋白组成发生了明显变化.这些变化对于揭示人神经母细胞瘤细胞癌变与逆转机制和肿瘤细胞增殖与分化调控机理均有十分重要的意义,从而为研究神经系统正常发育过程及神经系统疾病的发病机理提供科学依据.

Differentiation of Human Neuroblastoma SK-N-SH Cells and Alteration of Its Nuclear Matrix Proteins Induced by Retinoic Acid

The alteration of the nuclear matrix proteins (NMPs) during differentiation of human neuroblastoma SK-N-SH cells after being induced by retinoic acid (RA) have been investigated by immunocytochemistry, selective extraction-whole mount optic and two-dimensional gel electrophoresis. It revealed that RA could induce neuroblastoma cells to extend neurite-like processes. The immunocytochemistry observation revealed that the expression of neuronal markers, including synaptophysin, NSE, MAP2 were up-regulated in SK-N-SH after RA treatment. And the 2-DE result displayed that 52 nuclear matrix proteins, 41 of which were identified by mass spectrometry, were differently expressed after being treated with RA. The changes of nucleophosmin, prohibitin and hnRNP A2/B1 differently expressed in nuclear matrix proteins during differentiation induced by RA, was further confirmed by Western blotting. It demonstrated that SK-N-SH cells had been undergone a restorational change similar to normal neural cells after RA treatment. And induced differentiation SK-N-SH cells are companied with the expression alteration of NMPs. This alteration is important to reveal the relationship between nuclear matrix proteins and neuroblastoma cell carcinogenesis and reversion, and to elucidate the regulational principal of cell proliferation and differentiation.