辐射诱发大鼠气管上皮细胞恶性转化过程中染色体非随机异常

NONRANDOM CHROMOSOME CHANGES IN RAT TRACHEAL EPITHELIAL CELL LINE TRANSFORMED BY RADIATION

本文采用Ｇ显带技术研究了辐射致大鼠气管上皮（ＲａｔＴｒａｃｈｅａｌＥｐｉｔｈｅｌｉｕｍ，ＲＴＥ）细胞体外恶性转化过程中染色体非随机异常，结果：（１）细胞受照后，在传代早期以亚二倍体细胞为主，随传代次数增加其比例逐渐降低，在传代后期以多倍体细胞为主，这种变化趋势可能与细胞转化进展有关；（２）在转化细胞，１５号染色体长臂重排（１５ｑ＋）为其特征性染色体改变，它可能在ＲＴＥ细胞恶性转化过程中起重要作用；（３）Ｍａｒｋｅｒ染色体Ｍ１、Ｍ２和Ｍ３随传代次数增加发生频率逐渐升高，特别是Ｍ１和Ｍ２在致瘤细胞高频出现（＞９０％），提示可能与细胞转化进展有关。

Cytogenetic analysis was performed on one cell line which were derived from rat tracheal epithelium(RTE) cells transformed by α-particles irradiation in vitro.The passages of 5th,18th,39th and colony cells of 40th passage from soft agar(SA) culturing were observed.The results showed that the majority of cells was near-diploid at early passage,but was polypolid at late passage.This changing tendency of chromosome numbers with passaging might be related to transformative progression.And the increasing of long arm of chromosome 15(15q +) which was frequent at 5th passage and occurred in a clonal fashion(100%) in SA cells suggested a correlation with neoplastic transformation of RTE cells.Meanwhile,three Marker chromosomes of M1,M2 and M3 showed passage-dependent increasing.Especially M1 and M2 which were highly frequent in tumourigenic cells might be involved in transformative progression.