Effect of Notch1 gene silencing by RNA interference on proliferation and apoptosis of human breast cancer line MCF-7

Purpose To explore the proliferation and apoptosis of human breast cancer MCF-7 cell by applying RNA interference technique to silence Notch1 gene.Methods Four small fragments of siRNA and one negative control were sequenced and cloned into the vector.The recombinant plasmids were then transfected into breast cancer cell line MCF-7 by Sofast transfection assay.The transcription and translation level of Notch1 expression were detected by RT-PCR and Western blot.Meanwhile,the proliferation and apoptosis of transfected tumor cells were determined by cck8 and flow-cytometry assay.The protein expressions of NF-κB and Caspase-3 were detected by Western Blot.Results The recombinant plasmids containing Notch1 shRNA were successfully constructed.Notch1 expression was significantly knocked down after shRNA plasmid transfection(P0.05).Notch1 shRNA visibly inhibited the proliferation of breast cancer cell(P0.05)and the apoptosis rate increased after 48 h transfection(P0.01).The expression of NF-κB decreased but the expression of Caspase-3 increased significantly.Conclusions Notch1 gene silenced by shRNA can inhibit the proliferation and induce the apoptosis of human breast cancer cell line MCF-7 which may be regulated though NF-κB pathway,and the process might serve as a potential approach for breast cancer gene therapy.