α粒子诱发人支气管上皮细胞BEP2D癌变克隆的细胞遗传学分析

Cytogenetic analysis of malignant transformants of human bronchial epithelial cells BEP2D generated by α-particles exposure

目的 :分析α_粒子诱发人支气管上皮细胞BEP2D恶性转化细胞克隆的核型 ,探讨辐射致癌的细胞遗传学变化规律。方法 :1.5Gyα粒子照射BEP2D细胞恶性转化后进行亚克隆 ,用G带显示法分析亚克隆细胞核型。结果 :分析了 5个恶性转化亚克隆细胞 (BERP35T_1,_2 ,_4 ,_5 ,_6 ) ,基本核型与亲本细胞BEP2D相近 ,但有着明显的染色体缺失差异。BERP35T癌变细胞系缺失 1条 13号染色体和Y染色体 ;1条 2号染色体的长臂增加 ;缺失正常的12号染色体 ,出现 1条长臂增加的 12号染色体。此外 ,2株癌变细胞 (BERP35T_2和BERP35T_4 )多倍体高达 4 0 % ,明显高于BEP2D细胞。结论 :染色体缺失 (尤其是 13号染色体缺失 )是辐射致癌的一个显著遗传学特点 ,2号和 12号染色体长臂增加可能导致某些肿瘤相关基因的扩增或激活 ,促进细胞的恶性转化。

Objective: To analyze the cytogenetic changes in malignant transformants of human bronchial epithelial cell line (BEP2D) generated by α_particles exposure.Methods:Tumor cell lines were derived from nude mice bearing malignant transformed cells generated from cells of passage 35 of 1.5 Gy α_particles_irradiated BEP2D cells. G_banding patterns of chromosomes was used to analyze the karyotypes.Results:Five individual malignant transformed cell lines were analyzed. Deletions of one copy of chr13 and chrY, and an unidentified fragment attached to the long arms of chr2 and chr12 respectively (chr2q +, chr12q +) were observed in all the malignant transformed cell lines. The proportion of polyploids of BERP35T_2 and BERP35T_4 cells was about 40 % and was higher than that of PEB2D cells(5%).Conclusions:The process of cellular malignant transformation induced by α_particles exposure could involve some characteristic cytogenetic changes.