氯化镉诱导细胞c-fos和c-jun原癌基因转录表达

目的 探讨镉化物的分子致癌机理。方法 应用差异RT－PCR技术对氯化镉（CdCl2)诱导BALB／c-3T3细胞原癌基因c-fos和c-jun进行研究。结果 氯化镉在5－40μmol/L浓度范围内可诱导细胞原癌基因c-fos转录表达，与对照组比较，其差异有高度显著性。经与β-actin标准化后，氯化镉染毒浓度与c-fos表达水平之间存在明显的剂量反应关系。同样，氯化镉在20－40μmol/ml浓度范围内可致另一种细胞原癌基因c-jun高表达。结论 本研究结果提示，原癌基因c-fos和c-jun的超额表达与氯化镉的分子毒作用密切相关。这些结果可部分解释镉化合物的细胞转化作用及其可能的致癌机理。

Induction of Proto-oncogens c-fos and c-jun Expression in BALB/c-3T3 Cells by Cadmium Chloride

OBJECTIVE: This study was aimed to explore the possible carcinogenic mechanisms of cadumium and its related compounds involved at the molecular level. METHODS: We investigated the alternations in expressions of the proto-oncogens c-fos and c-jun in BALB/c-3T3 cells induced by cadmium chloride (CdCl2), using differential RT-PCR protocol. RESULTS: It was found that 2 hours after the cells were exposed to CdCl2, overexpression of an immediate early proto-oncogen c-fos was observed in BALB/c-3T3 cells treated with CdCl2 in concentrations ranging from 5 mumol/ml to 40 mumol/ml, and there was a significant dose-dependent relationship between the concentrations of CdCl2 and the levels of c-fos expression after normalization with beta-actin. In the same way, elevated expression of another immediate early proto-oncogen, c-jun, was induced with CdCl2 in concentrations from 20 to 40 mumol/ml. CONCLUSION: The results seem to indicate that overexpressions of c-fos and c-jun are related to genotoxicity of CdCl2. These results might partly explain the cell transformation and carcinogenesis of cadmium.