p53基因在RA诱导SH-SY5Y细胞分化后低表达

全反式维甲酸(RA)的抑制肿瘤细胞生长和调控细胞分化的作用是一项重要的研究课题。而p53基因是一个重要的肿瘤抑制基因,在RA的作用中是否涉及到p53的作用尚有待阐明。本文用低浓度的RA(10 μmol/L)作用于SH-SY5Y细胞,每2d换一次液,在作用9 d后,用光学显微镜观察SH-SY5Y细胞的形态学变化,并提取细胞质总RNA进行RT-PCR反应半定量检测p53基因表达。结果显示,SH-SY5Y细胞经RA诱导后,细胞生出较长的突起,具有神经元的形态;而对照组保持成纤维细胞的形态、无明显的形态学变化。RT-PCR半定量显示,在细胞诱导后,p53基因表达明显下调。本文结果提示,RA的作用可能独立于p53基因途径,p53基因的表达变化可能是继发于RA的作用。

RETINOIC ACID DECREASED p53 EXPRESSION LEVEL IN SH-SY5Y CELLS

To investigate the effects of all-trans retinoic acid (RA) on p53 gene expression level after differentiation, SH-SY5Y cells were cultured with 10 μmol/L RA and allowed to grow for 8 days. Medium containing RA was changed every second day. Morphologic features of cells were observed by Nikon light microscope. p53 gene expression was determined by RT-PCR. The results showed: (1) SH-SY5Y cells incubated with RA outgrew neuritis, appearing neuronal phenotype. The control cells retained fibroblast-like shape. (2) p53 gene expression level was decreased in cells cultured with RA in contrast with the control. This study suggests that the effects of RA on SH-SY5Y cells might be independent on p53 pathway, and down-regulation of p53 gene can be sequential to the effects of RA.