title: Simultaneous inhibition of the HGF/MET and Erk1/2 pathways affect uveal melanoma cell growth and migration.
abstract: OBJECTIVE
  Nearly all primary uveal melanoma (UM) that metastasize involve the liver. Hepatocyte growth factor (HGF) is proposed to be an important microenvironmental element in attracting/supporting UM metastasis through activation of MET. The majority (>85%) of UM express mutations in the G-alpha proteins, that drive the MEK-ERK1/2 pathway. Thus, we proposed that the combination of MET and MEK inhibition would inhibit the growth and migration of G-alpha protein mutant versus non-mutant UM cells.
  
  
  METHODS
  Western-blots demonstrated the relative protein levels of ERK1/2 and MET in UM cells. Cells were treated with the small molecule inhibitors AZD6244 (MEKi) and/or MK-8033 (METi) and downstream markers evaluated. Further studies determined the effect of combination MEKi and METi treatment on cell growth, apoptosis and migration.
  
  
  RESULTS
  All G-alpha protein mutant UM cell lines express MET mRNA and protein. The level of mRNA expression correlates with protein expression. MEKi, but not METi treatment results in markedly reduced ERK1/2 phosphorylation. Either MEKi or METi treatment alone results in reduced cell proliferation, but only modest induction of apoptosis. The combination MEKi+METi results in significant reduction of proliferation in G-alpha protein mutant cells. UM cell migration was blocked by METi, but not MEKi treatment.
  
  
  CONCLUSIONS
  MET protein expression showed no correlation with G-alpha protein mutation status. Combining MEKi with METi treatment has added benefit to either treatment alone in reducing G-alpha protein mutant UM cell growth. Combining METi with MEKi treatment adds the effect of limiting uveal melanoma cell migration.
authors.affiliation: Melanoma Medical Oncology, University of Texas, MD Anderson Cancer Center, Houston, Texas, United States of America.
authors.forename: Chandrani
authors.initials: C
authors.lastname: Chattopadhyay
authors.affiliation: Melanoma Medical Oncology, University of Texas, MD Anderson Cancer Center, Houston, Texas, United States of America.
authors.forename: Elizabeth A
authors.initials: EA
authors.lastname: Grimm
authors.affiliation: Melanoma Medical Oncology, University of Texas, MD Anderson Cancer Center, Houston, Texas, United States of America ; Systems Biology, University of Texas, MD Anderson Cancer Center, Houston, Texas, United States of America.
authors.forename: Scott E
authors.initials: SE
authors.lastname: Woodman
mesh_terms: D017209:Apoptosis / Q000187:drug effects; D001562:Benzimidazoles / Q000494:pharmacology; D001567:Benzocycloheptenes / Q000494:pharmacology; D002453:Cell Cycle / Q000187:drug effects; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D044385:GTP-Binding Protein alpha Subunits / Q000235:genetics / Q000378:metabolism; D043802:GTP-Binding Protein alpha Subunits, Gq-G11; D015972:Gene Expression Regulation, Neoplastic; D017228:Hepatocyte Growth Factor / Q000037:antagonists & inhibitors / Q000235:genetics* / Q000378:metabolism; D006801:Humans; D019950:Mitogen-Activated Protein Kinase 1 / Q000037:antagonists & inhibitors / Q000235:genetics* / Q000378:metabolism; D048052:Mitogen-Activated Protein Kinase 3 / Q000037:antagonists & inhibitors / Q000235:genetics* / Q000378:metabolism; D009154:Mutation; D047428:Protein Kinase Inhibitors / Q000494:pharmacology; D019859:Proto-Oncogene Proteins c-met / Q000037:antagonists & inhibitors / Q000235:genetics* / Q000378:metabolism; D015398:Signal Transduction; D013449:Sulfonamides / Q000494:pharmacology
chemical_list: C517975:AZD 6244; D001562:Benzimidazoles; D001567:Benzocycloheptenes; C554061:GNAQ protein, human; D044385:GTP-Binding Protein alpha Subunits; C066855:HGF protein, human; D047428:Protein Kinase Inhibitors; D013449:Sulfonamides; C581209:1-(3-(1-methyl-1H-pyrazol-4-yl)-5-oxo-5H-benzo(4,5)cyclohepta(1,2-b)pyridin-7-yl)-N-(pyridin-2-ylmethyl)methanesulfonamide; D017228:Hepatocyte Growth Factor; C491743:MET protein, human; D019859:Proto-Oncogene Proteins c-met; C535150:MAPK1 protein, human; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D043802:GTP-Binding Protein alpha Subunits, Gq-G11