NNK及X-射线诱导大鼠气管上皮细胞转化的研究

本文采用无血清F12培养基培养大鼠气管上皮(RTE)细胞。RTE细胞可在该种培养基中生长,增殖。形成典型的上皮细胞集落。当无血清培养基换成含血清的选择性培养基时,正常细胞停止生长进而退化死亡,而转化的RTE细胞则可以继续生长,成为转化集落。转化集落经多次传代可在裸鼠体内引起肿瘤。大鼠暴露于致癌物NNK或X射线后,收集其RTE细胞,先在体外进行无血清培养然后再进行选择性培养,其转化率明显高于对照组。RTE细胞体内—体外转化实验对于探究人类肺癌发生机制有一定意义。

STUDY ON TRANSFORMATION OF RAT TRACHEAL EPITHELIAL CELLS INDUCED BY NNK OR X RAY

In this study, serum-free F12 medium was used for the culture of rat tracheal epithelial (RTE) cells. RTE cells can grow, proliferate and form typical epithelial cell colonies in this medium. The colony forming efficiency of RTE cells is about 1%.Normal RTE cells cease to proliferate and senesce after serum-free F12 medium was replaced by serum-containing selective F12 medium without several growth fectors.In contrast, carcinogen-altered RTE cells continue to grow and form transformed colonies.Many of the carcinogen-altered RTE cells can be subcultured and become immortalized cell lines. Squamous cell carcinoma developed in nude mice inoculated with transformed RTE cells of high passage. Furthermore, an in vivo-in vitro transformation assay of RTE cells was developed. The frequency of transformed colonies increased in tracheal epithelial cells of rats exposed to NNK or X-rays in vivo. This new in vivo-in vitro transformation assay is significance.