论文部分内容阅读
研究了维甲酸（ＲＡ）对鼻咽癌细胞生长、表型和癌基因表达的作用．用ＲＡ诱导鼻咽癌细胞，绘制诱导前后的细胞曲线，观察细胞形态，并用Ｎｏｒｔｈｅｒｎ杂交和ＤＮａｓｅⅠ超敏感区分析法检测基因表达和调控．结果表明，ＲＡ能显著抑制鼻咽癌细胞的生长，前５ｄ下降约５０％．ＲＡ处理后的细胞从典型的多边形形态变成扁平、细长，类似纤维细胞状的形态．ＲＡ诱导前ｃ－ｍｙｃ基因和ｃ－Ｈａ－ｒａｓ基因ＨＮＥ２细胞中高表达，而诱导后ｃ－ｍｙｃ基因表达水平急剧下降，ｃ－Ｈａ－ｒａｓ基因无明显改变．在实验中还发现ＲＡ诱导前后的ｃ－ｍｙｃ基因和ｃ－Ｈａ－ｒａｓ基因中一些重要的超敏感位点和它们的功能．由实验结果可得到如下结论：ＲＡ能促进鼻咽癌细胞分化，通过对染色体上调控位点的作用来抑制ｃ－ｍｙｃ基因的表达，ＤＮａｓｅⅠ超敏感位点与细胞的分化程度、细胞的组织特异性和基因表达状态有关，ｃ－ｍｙｃ基因可通过不同的调控方式而失活．
The effect of retinoic acid (RA) on the growth, phenotype and oncogene expression of nasopharyngeal carcinoma cells was studied. Nasopharyngeal carcinoma cells were induced by RA, the cell curve was drawn before and after induction, and the cell morphology was observed. The gene expression and regulation were detected by Northern blot and DNase Ⅰ hypersensitivity analysis. The results showed that RA could significantly inhibit the growth of nasopharyngeal carcinoma cells by about 50% in the first 5 days. RA-treated cells changed from a typical polygonal morphology to a flat, elongated, fibroblast-like morphology. The c-myc gene and c-Ha-ras gene HNE2 cells were highly expressed in RA before induction, while the expression of c-myc gene was abruptly decreased after induction, while the c-Ha-ras gene was not significantly changed. Some important hypersensitivity sites and their functions in c-myc and c-Ha-ras genes before and after RA induction were also found in experiments. From the experimental results, we can draw the following conclusions: RA can promote nasopharyngeal carcinoma cell differentiation, inhibit the expression of c-myc gene through the role of chromosomal regulatory sites, DNase Ⅰ hypersensitivity sites and cell differentiation, cell tissue specificity Sex and the status of gene expression, c-myc gene can be inactivated by different regulatory methods.