Ras基因家族在二羟环氧苯并(a)芘恶性转化细胞中的表达研究

目的检测环境致癌物苯并(a)芘代谢物二羟环氧苯并芘(BPDE)对人支气管上皮细胞Ras基因家族表达的影响。方法以正常人支气管上皮细胞为对照组,经BPDE恶性转化人支气管上皮细胞为实验组,分别利用RT-PCR、Western blot和免疫细胞化学方法,检测Ras基因家族在mRNA和蛋白水平表达变化。结果RT-PCR实验表明,BPDE恶性转化细胞H-Ras、K-Ras和N-Ras mRNA表达水平分别是正常细胞的2.237、1.254和3.616;Western blot实验显示,H-Ras、K-Ras和N-Ras蛋白表达量分别是正常细胞的1.273倍、1.547和1.600倍;免疫细胞化学实验表明,恶性转化细胞H、K和N-Ras蛋白表达明显强于正常细胞。结论BPDE诱发人支气管上皮细胞恶性转化存在H-Ras、K-Ras和N-Ras基因过表达。

Study on expression of Ras family gene in transformed cells induced by BPDE

OBJECTIVE: To explore the expression of Ras family gene in the malignantly transformed human bronchial epithelial cell line induced by anti-benzo(a)pyrene-trans-7,8- dihydrodiol-9,10-epoxide(BPDE). METHODS: The levels of H-Ras, K-Ras and N-Ras mRNA expression in BPDE transformed 16HBE cells (16HBE-T) and untransformed control 16HBE cells (16HBE-N) were examined using RT-PCR. Expression levels of those three proteins in both kinds of cells were analyzed by western blot and immunocytochemical method. RESULTS: Compared with 16HBE-N, the levels of H-Ras, K-Ras and N-Ras mRNA expression were significantly increased to 2.237, 1.254 and 3.616 times in 16HBE-T, and the protein levels of those genes were increased to 1.273, 1.547 and 1.600 times, respectively. Immunocytochemical method showed expression levels of those proteins in 16HBE-T were significantly higher than those in 16HBE-N. CONCLUSION: H-Ras, K-Ras and N-Ras are overexpressed in 16HBE-T. The activation of oncogenic Ras may participate in malignant transformation of 16HBE induced by BPDE.