title: [EFEMP1 suppresses growth and invasion of lung cancer cells  by downregulating matrix metalloproteinase-7 expression].
abstract: BACKGROUND
  EFEMP1, a member of fibulin family proteins, is a very important extracellular matrix protein which is involved in cell metabolism and its role in tumor occurrence and progression is still poorly understood. The aim of this study is to investigate the functional effect and mechanism of EFEMP1 in lung cancer cell growth and invasion.
  
  
  METHODS
  EFEMP1 expression in lung cancer cells was determined by Western blot. The promoter methylation status of EFEMP1 was detected by methylation-specific PCR (MSP). After transfection of control or EFEMP1 vector in lung cancer cells, the ability of colony formation and invasion was detected by colony formation experiment and matrigel invasion method. Western blot and real-time PCR were used to detect matrix metalloproteinase-7 (MMP-7) expression. Luciferase assay was used to detect expression of MMP-7 reporter construct transfected with or without EFEMP1 in lung cancer cells.
  
  
  RESULTS
  Western blot result showed EFEMP1 expression was downregulated in lung cancer cells. The promoter region of EFEMP1 was methylated in A549 and H1299 and after treatment with 5-aza-2'-deoxycytidine, the EFEMP1 expression was upregulated. The growth and invasion of A549 and H1299 were all significantly suppressed by transfecting with EFEMP1 and the MMP-7 expression was dowanregulated by EFEMP1 as well. Expression activity of MMP-7 reporter construct was decreased by cotransfecting with EFEMP1.
  
  
  CONCLUSIONS
  Collectively, these results suggest that EFEMP1 functions as a suppressor of lung cancer growth and invasion. Epigenetic silencing of EFEMP1 promotes lung cancer invasion and metastasis by activating MMP-7 expression.
authors: Department of Clinical Laboratory, Tianjin Children's Hospital, Tianjin 300074, China.
authors: Yuanyuan
authors: Y
authors: Lang
authors: Department of Immunology, Basic Medical College, Tianjin Medical University, Tianjin 300070, China.
authors: Jie
authors: J
authors: Meng
authors: Department of Immunology, Basic Medical College, Tianjin Medical University, Tianjin 300070, China.
authors: Xiaomeng
authors: X
authors: Song
authors: Department of Immunology, Basic Medical College, Tianjin Medical University, Tianjin 300070, China.
authors: Xiaojun
authors: X
authors: Chen
mesh_terms: D045744:Cell Line, Tumor; D049109:Cell Proliferation; D019175:DNA Methylation; D015536:Down-Regulation; D016326:Extracellular Matrix Proteins / Q000235:genetics / Q000378:metabolism*; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008175:Lung Neoplasms / Q000201:enzymology* / Q000235:genetics / Q000473:pathology / Q000503:physiopathology; D020783:Matrix Metalloproteinase 7 / Q000235:genetics* / Q000378:metabolism; D009361:Neoplasm Invasiveness; D011401:Promoter Regions, Genetic
chemical_list: C119630:EFEMP1 protein, human; D016326:Extracellular Matrix Proteins; D020783:Matrix Metalloproteinase 7