二氯乙酸对ras基因的DNA损伤作用

DNA damage of ras gene induced by dichloroacetic acid

目的研究二氯乙酸(dichloroacetic acid,DCA)对ras基因的DNA损伤作用,探讨其致癌作用分子机制。方法制备各ras基因外显子单链探针;DCA染毒TK6细胞,提取基因组DNA,再经RDPCR扩增,扩增产物与探针杂交显色。结果成功制备各ras基因外显子单链探针,Southern杂交检测到DCA对N-ras基因外显子2和H-ras基因外显子2的DNA损伤片段杂交条带,未检测出其对N-ras基因外显子1和H-ras基因外显子1的DNA损伤作用。结论DCA可造成ras基因DNA损伤,可能与其致癌作用机制密切相关,属于遗传毒性物质。

Objective Applying randomized terminal linker-dependent PCR（RDPCR） to detect the DNA damage of ras gene induced by diehloroacetie aeid（DCA） .Methods Preparing single-stranded probes of exons of ras gene in human. The TK6 cell was treated with DCA, then the genomie DNA was amplified by RDPCR and detected by Southern hybridization with the probes. Results Single-stranded probes of exons of ras gene were prepared. From the Southern blot, the clear hybridized bands induced by DCA could be seen in the position of exon 2 of N- ras and H- ras gene respectively, but those of exon 1 of N- ras and H- ras gene were not detected. Conclusion DCA can cause the DNA damage of ras gene, which would has strong correlation with it＇s mechanism of carcinogenesis, so it is a kind of genotoxic substance.