title: Relationship Between HSP70 and ERBB2 Expression in Breast Cancer Cell Lines Regarding Drug Resistance.
abstract: BACKGROUND
  Heat shock protein 70 (HSP70) is known to be downstream of human epidermal growth factor receptor-2 (ERBB2), but little is known regarding the relationship between HSP70 and drug resistance mediated by ERBB2 in breast cancer.
  
  
  METHODS
  After infecting breast cancer cells with lentivirus-mediated Lenti-ShHSP70 and Lenti-ShERBB2, we examined the expression of HSP70 and ERBB2 by real-time polymerase chain reaction and western blotting.
  
  
  RESULTS
  Compared to the control groups, mRNA expression of HSP70 was decreased in lentivirus-infected, and western blotting indicated a concordant reduction of HSP70 protein. On the other hand, ERBB2 was significantly down-regulated by HSP70 silencing in SK-BR-3 cells at both the mRNA and protein levels. Expression of HSP70 in transfected cells was also reduced by Lenti-ShERBB2. CCK8 viability assay indicated that inhibition of HSP70 increased the sensitivity of SK-BR-3 cells to fluorouracil treatment.
  
  
  CONCLUSIONS
  HSP70 affects ERBB2 and ERBB2-mediated drug-resistance in breast cancer cells.
authors.affiliation: Department of Oncology, Qingdao Municipal Hospital, School of Medicine, Qingdao University, Qingdao, P.R. China.
authors.forename: L U
authors.initials: LU
authors.lastname: Yue
authors.affiliation: Department of Oncology, Yantai Yuhuangding Hospital Affiliated To Qingdao University, Yantai, P.R. China.
authors.forename: Jin-Yu
authors.initials: JY
authors.lastname: Xiang
authors.affiliation: Department of Oncology, Yantai Yuhuangding Hospital Affiliated To Qingdao University, Yantai, P.R. China.
authors.forename: Ping
authors.initials: P
authors.lastname: Sun
authors.affiliation: Department of Oncology, Qingdao Municipal Hospital, School of Medicine, Qingdao University, Qingdao, P.R. China.
authors.forename: Ya-Sai
authors.initials: YS
authors.lastname: Yao
authors.affiliation: Department of Oncology, Qingdao Municipal Hospital, School of Medicine, Qingdao University, Qingdao, P.R. China.
authors.forename: Zhen-Ni
authors.initials: ZN
authors.lastname: Sun
authors.affiliation: Centre for Medical Research, The Affiliated Hospital of Qingdao University, Qingdao, P.R. China.
authors.forename: Xiang-Ping
authors.initials: XP
authors.lastname: Liu
authors.affiliation: Departments of Galactophore Surgery, The Affiliated Hospital of Qingdao University, Qingdao, P.R. China.
authors.forename: Hai-Bo
authors.initials: HB
authors.lastname: Wang
authors.affiliation: Department of Oncology, The Sixth People's Hospital, Medical College, Shanghai Jiao Tong University, Shanghai, P.R. China.
authors.forename: Zan
authors.initials: Z
authors.lastname: Shen
authors.affiliation: Centre for Medical Research, The Affiliated Hospital of Qingdao University, Qingdao, P.R. China yry0303@163.com.
authors.forename: Ru-Yong
authors.initials: RY
authors.lastname: Yao
mesh_terms: D000964:Antimetabolites, Antineoplastic / Q000494:pharmacology*; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D019008:Drug Resistance, Neoplasm; D005260:Female; D005472:Fluorouracil; D015972:Gene Expression Regulation, Neoplastic; D018840:HSP70 Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D034622:RNA Interference; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000235:genetics / Q000378:metabolism*; D014162:Transfection
chemical_list: D000964:Antimetabolites, Antineoplastic; D005472:Fluorouracil; D018840:HSP70 Heat-Shock Proteins; D012333:RNA, Messenger; D018719:Erb-b2 Receptor Tyrosine Kinases; C508053:ERBB2 protein, human
keywords: ERBB2; HSP70; breast cancer; drug resistance; fluorouracil; lentivirus