title: Lentivirus-mediated inhibition of Med19 suppresses growth of breast cancer cells in vitro.
abstract: OBJECTIVE
  The mediator is a large multiprotein complex vital for transcription regulation. Human Med19 is a critical subunit of the mediator complex and plays an important role in stabilizing the whole mediator. To understand the role and mechanism of Med19 in breast cancer, we carried out studies on the impacts of lentivirus-mediated inhibition of Med19 on breast cancer cells in vitro.
  
  
  METHODS
  The expression of Med19 in breast cancer tissue was detected using immunohistochemical analysis. The impacts of lentivirus-mediated inhibition of Med19 on breast cancer cells were detected using flow cytometric, cell proliferation, BrdU incorporation, and colony formation assays.
  
  
  RESULTS
  The upregulated expression of Med19 was found in breast cancer tissues. Med19 expression was significantly associated with tumor grade (p = 0.026). The expression of Med19 was strongly suppressed in human breast cancer MDA-MB-231 and MCF-7 cells infected with lentiviruses delivering small hairpin RNA (shRNA) against Med19. The inhibition of Med19 elicited augmentation of G0/G1 phase proportion and significantly attenuated the growth of MDA-MB-231 and MCF-7 cells in vitro.
  
  
  CONCLUSIONS
  Med19 plays an important role in the proliferation of human breast cancer cells, which suggested that the lentiviruses delivering shRNA against Med19 could be a promising tool for breast cancer therapy.
authors.affiliation: Oncology Institute, The Fourth Affiliated Hospital of Soochow University, 200 Huihe Road, Wuxi 214062, China. lihuali_1@yahoo.cn
authors.forename: Li-Hua
authors.initials: LH
authors.lastname: Li
authors.forename: Jie
authors.initials: J
authors.lastname: He
authors.forename: Dong
authors.initials: D
authors.lastname: Hua
authors.forename: Zi-Jian
authors.initials: ZJ
authors.lastname: Guo
authors.forename: Qi
authors.initials: Q
authors.lastname: Gao
mesh_terms: D001943:Breast Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology / Q000628:therapy*; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D005260:Female; D016193:G1 Phase; D006801:Humans; D016086:Lentivirus / Q000235:genetics*; D056892:Mediator Complex / Q000235:genetics* / Q000378:metabolism*; D010957:Plasmids; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000235:genetics*; D014158:Transcription, Genetic; D015854:Up-Regulation
chemical_list: C558319:MED19 protein, human; D056892:Mediator Complex; D034741:RNA, Small Interfering