RESUMO
<p><b>OBJECTIVE</b>To construct DNA double-strand break (DSB) repair protein hKu70 deficient cell strain and to observe its biological characters for studying the functions of hKu70 gene and the effects of occupational harmfulness factors on DSB repair.</p><p><b>METHODS</b>Human lung fibroblasts (HLF) were transfected with the eukaryotic expression plasmids of hKu70 gene antisense RNA (pEGFP-C1-K) to construct hKu70 protein deficient cells (named as "HLFK"). The protein expression levels of hKu70 gene in HLFC and HLFK were detected by the Western blotting to estimate the effects of antisense inhibition. Morphology, growth character and growth status in soft agar of transfected HLFK were observed.</p><p><b>RESULTS</b>pEGFP-C1-K vector was successfully expressed in HLF. The protein expression level of hKu70 gene in HLFK was decreased by 42% as compared with that in HLFC. No obvious changes of the biologic characters were observed in HLFK.</p><p><b>CONCLUSION</b>The hKu70 protein deficient cell strain was successfully constructed. The hKu70 protein deficiency alone didn't induce obvious changes of the biological characters in HLFK.</p>