环磷酰胺、噻替哌诱发人支气管上皮细胞的染色体畸变

目的与方法：以永生化人支气管上皮细胞（ＢＥＡＳ－２Ｂ）受环磷酰胺、噻替哌诱导并发生癌性转化的细胞为模型，运用染色体Ｇ－显带技术，观察环磷酰胺、噻替哌的遗传病毒作用引起的细胞转化过程中的染色体动态畸变。结果：ＢＥＡＳ－２Ｂ细胞染色体众数４６条，近二倍体，核型稳定，携带有Ｍ１，Ｍ２，Ｍ３三个标志染色体。环磷酰胺转化细胞（ＢＥＡＳ－ＣＰ）为二倍体核型，丢失了１个１４号染色体，增加了Ｍ４异常染色体，该畸变可能与细胞转化的始动，促进和进展有关。噻替哌转化细胞（ＢＥＡＳ－Ｔ）在培养过程中渐趋多倍体细胞，１５代以后部分细胞的１４和２１号染色体各丢失１条，ＢＥＡＳ－Ｔ ２３代在软琼脂上形成克隆的细胞（ＢＥＡＳ－ＳＴ）是多倍体细胞，并具有高频率的非稳定性畸变，ＢＥＡＳ－Ｔ ２５代时为３％，ＢＥＡＳ－Ｓ为３４％，多倍体背景上出现２

CYTOGENETIC ANALYSIS OF TRANSFORMED HUMAN BROCHIAL EPITHELIAL CELLS INDUCED BY CYCLOPHOSPHAMIDE AND THIOTEPA

Purpose and Methods:Utilizing a cell transformed model composed of a human bronchial epithelial cell line(BEAS 2B), BEAS 2B cell transformed by cyclophosphamide (BEAS CP) and thiotepa (BEAS T),cytogenetic alteration associated with neoplastic transformation of human bronchial epithelial cells was observed. Res BEAS 2B cells have near diploid karyotype and genotypically stable. Three chromosomal markers present. BEAS CP cell was mainly diploid with a variable proportion of polyploid cells. Chromosome l4 has lost one of two copies of chromosome and chromosomal mark M4 has formed. Those changes might be the original {alteration} induced by alkylating effect of cyclophosphamide and as the primary alteration involved in transformed initiation, promotion and progression. BEAS T cell mainly consists of polyploid cells, some cells loss of monosomy of chromosome 8 and 21. BEAS T soft agar selected cells (BEAS ST) were all polyploid cells and characterized by a high frequency of unstable aberrations(from 3% of BEAS T 25p up to 34% of BEAS ST). Another special alteration for BEAS ST is two pairs of the largeness tricentric chromosome. Conclusion: These aberrations have a strong relatioship with cell malignant transformation and the transformed cells might have the tumorgenesis {ability} in nude mouse.