title: Combination of survivin siRNA with neoadjuvant chemotherapy enhances apoptosis and reverses drug resistance in breast cancer MCF-7 cells.
abstract: BACKGROUND
  Chemotherapeutic resistance is a main problem in clinical breast cancer therapy. The purpose of our study is to investigate whether the combination of neoadjuvant chemotherapy and survivin siRNA treatment could enhance the therapeutic effect of neoadjuvant chemotherapy using paclitaxel or epirubicin.
  
  
  METHODS
  The molecular cloning technique was applied to construct the expression vector of siRNA against survivin. Effectene Transfection Reagent was used to transfect plasmids to MCF-7 cells. Survivin expressions were detected by quantitative real-time PCR (qRT-PCR) and Western blot methods. The effect of paclitaxel or epirubicin, with or without the combination of survivin siRNA treatment, on drug susceptibility of MCF-7 cells was detected by CCK-8 assay. MCF-7 cell apoptosis was detected by Flow Cytometry.
  
  
  RESULTS
  Survivin siRNA effectively inhibited the expression of Survivin RNA and protein levels (P < 0.05). Both paclitaxel and epirubicin can suppress the proliferation of MCF-7 cells and induce apoptosis to a certain degree respectively. The combination of survivin siRNA with the two chemotherapy drugs significantly enhanced both effects of the two chemotherapeutics respectively (P < 0.05).
  
  
  CONCLUSIONS
  Survivin siRNA combined with the neoadjuvant chemotherapy can significantly enhance the sensitivity of MCF-7 cells to chemotherapeutics and cell apoptosis. This technology has important potential value in the therapeutic study of breast cancer.
authors.affiliation: Department of Vascular Surgery, Second Hospital, Shanxi Medical University, Taiyuan, China.
authors.forename: Honglin
authors.initials: H
authors.lastname: Dong
authors.forename: Luyu
authors.initials: L
authors.lastname: Yao
authors.forename: Weilin
authors.initials: W
authors.lastname: Bi
authors.forename: Fusheng
authors.initials: F
authors.lastname: Wang
authors.forename: Wei
authors.initials: W
authors.lastname: Song
authors.forename: Yonggang
authors.initials: Y
authors.lastname: Lv
mesh_terms: D000903:Antibiotics, Antineoplastic / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects*; D015153:Blotting, Western; D001943:Breast Neoplasms / Q000188:drug therapy / Q000235:genetics / Q000473:pathology*; D003131:Combined Modality Therapy; D019008:Drug Resistance, Neoplasm / Q000235:genetics*; D015251:Epirubicin / Q000494:pharmacology*; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D051034:Inhibitor of Apoptosis Proteins / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D020360:Neoadjuvant Therapy; D034741:RNA, Small Interfering / Q000235:genetics*; D060888:Real-Time Polymerase Chain Reaction; D000077022:Survivin; D014407:Tumor Cells, Cultured
chemical_list: D000903:Antibiotics, Antineoplastic; C107489:BIRC5 protein, human; D051034:Inhibitor of Apoptosis Proteins; D034741:RNA, Small Interfering; D000077022:Survivin; D015251:Epirubicin