Effects of HER-2 RNA interference on HER-2-positive breast cancer cell sensitivity to chemotherapeutic agent

OBJECTIVE:To study the effects HER-2 gene RNA interference (RNAi) on the chemo-sensitivity of HER-2-positive breast cancer cell. METHODS:A plasmid vector capable of mediating HER-2 RNAi was constructed,and HER-2 positive breast cancer cell line SKBR-3 was transfected with constructed vector. The expression of HER-2 mRNA and protein was analyzed by RT-PCR and Western blotting; Also,transfected cells were co-cultured with different concentrations of epirubicin and the growth of SKBR-3 cells was analyzed by MTT. RESULTS:The expression of HER-2 mRNA and HER-2 protein was downregulated about 60% and 55%,respectively,in response to vector-mediated HER-2 RNAi. Furthermore,the chemo-sensitivity to epirubicin of the SKBR-3 cell was enhanced significantly by HER-2 gene RNAi and the IC50 was 0.25 μg/μL. CONCLUSION:HER-2 is a good target for RNAi and RNAi,targeting HER-2 gene can cause HER-2 positive breast cancer cell growth inhibition and increasing sensitivity to chemotherapeutics.