title: Glial cell-derived neurotrophic factor upregulates the expression and activation of matrix metalloproteinase-9 in human pancreatic cancer.
abstract: BACKGROUND
  We have previously reported that the glial cell-derived neurotrophic factor (GDNF) promotes pancreatic cancer cell invasion in vitro. The purpose of this study was to determine whether GDNF regulates the expression and activation of matrix metalloproteinase-9 (MMP-9) in human pancreatic cancer cells.
  
  
  METHODS
  We used human pancreatic cancer cell line MIA PaCa-2. The effect of GDNF on mRNA and protein expression was measured by Northern blot, Western blot and enzyme-linked immunosorbent assay. MMP proteolytic activity was detected by gelatin zymography. To determine which intracellular pathways were involved, we used the following inhibitors: tyrosine kinase inhibitor Genistein, MEK-1 inhibitor PD98059 and PI3-K inhibitor Wortmannin.
  
  
  RESULTS
  GDNF increased MMP-9 mRNA and protein expression in MIA PaCa-2 cells in a dose-dependent manner. Treatment with GDNF enhanced gelatinolytic activity of the pro and active form of MMP-9. Inhibitor experiments showed that the expression and activity of pro MMP-9 was totally inhibited by Genistein and partially by Wortmannin, whereas PD98059 had no effect. All three compounds inhibited the activity of the active form of MMP-9.
  
  
  CONCLUSIONS
  GDNF upregulates the expression and enzymatic activity of MMP-9 through different signaling pathways in MIA PaCa-2. These findings suggest that GDNF modulates MMP-9 expression and activation, and this may promote pancreatic cancer invasion.
authors.affiliation: Section of Gastrointestinal Surgery, the David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA.
authors.forename: Yuji
authors.initials: Y
authors.lastname: Okada
authors.forename: Guido
authors.initials: G
authors.lastname: Eibl
authors.forename: John P
authors.initials: JP
authors.lastname: Duffy
authors.forename: Howard A
authors.initials: HA
authors.lastname: Reber
authors.forename: Oscar J
authors.initials: OJ
authors.lastname: Hines
mesh_terms: D003470:Culture Media / Q000737:chemistry; D004305:Dose-Response Relationship, Drug; D004789:Enzyme Activation / Q000187:drug effects; D005780:Gelatin / Q000378:metabolism; D051100:Glial Cell Line-Derived Neurotrophic Factor; D006801:Humans; D020780:Matrix Metalloproteinase 9 / Q000235:genetics / Q000378:metabolism*; D009414:Nerve Growth Factors / Q000008:administration & dosage / Q000494:pharmacology*; D010190:Pancreatic Neoplasms / Q000201:enzymology / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D011994:Recombinant Proteins / Q000008:administration & dosage / Q000494:pharmacology; D014407:Tumor Cells, Cultured; D015854:Up-Regulation / Q000187:drug effects
chemical_list: D003470:Culture Media; C495039:GDNF protein, human; D051100:Glial Cell Line-Derived Neurotrophic Factor; D009414:Nerve Growth Factors; D012333:RNA, Messenger; D011994:Recombinant Proteins; D005780:Gelatin; D020780:Matrix Metalloproteinase 9