title: A role for Jag2 in promoting uveal melanoma dissemination and growth.
abstract: OBJECTIVE
  Controlling the spread of uveal melanoma is key to improving survival of patients with this common intraocular malignancy. The Notch ligand Jag2 has been shown to be upregulated in primary tumors that metastasize, and we therefore investigated its role in promoting invasion and clonogenic growth of uveal melanoma cells.
  
  
  METHODS
  mRNA and protein expression of Notch pathway components were measured using qPCR and Western blot in uveal melanoma cell lines. Expression of Jag2 ligand was upregulated using Jag2-GFP-MSCV constructs or downregulated by sh-Jag2 in the uveal melanoma cell lines Mel285, Mel290, 92.1, and OMM1, and the effects on growth and invasion were assessed.
  
  
  RESULTS
  Jag2 was introduced into Mel285 and Mel290 cells, which have low baseline levels of both this ligand and Notch activity. Overall growth of the Jag2-expressing cultures increased somewhat, and a significant 3-fold increase in clonogenic growth in soft agar was also noted. Introduction of Jag2 increased motility in both wound-healing and transwell invasion assays. We also observed a significant increase in Jag2 and Hes1 mRNA in invasive OMM1 cells that had passed through a Matrigel-coated filter in the transwell assay when compared with noninvading cells. Loss-of-function studies performed in 92.1 and OMM1 lines using Jag2 shRNAs showed that downregulation of the ligand significantly suppressed cellular growth, invasion, and migration.
  
  
  CONCLUSIONS
  Our data suggest that Jag2 may play an important role in promoting Notch activity, growth, and metastasis in uveal melanoma.
authors.affiliation: Department of Pathology, Johns Hopkins University, School of Medicine, Baltimore, Maryland 21287, USA.
authors.forename: Laura
authors.initials: L
authors.lastname: Asnaghi
authors.forename: James T
authors.initials: JT
authors.lastname: Handa
authors.forename: Shannath L
authors.initials: SL
authors.lastname: Merbs
authors.forename: J William
authors.initials: JW
authors.lastname: Harbour
authors.forename: Charles G
authors.initials: CG
authors.lastname: Eberhart
mesh_terms: D051792:Basic Helix-Loop-Helix Proteins / Q000235:genetics / Q000378:metabolism; D015153:Blotting, Western; D045744:Cell Line, Tumor; D002465:Cell Movement; D018398:Homeodomain Proteins / Q000235:genetics / Q000378:metabolism; D006801:Humans; D036341:Intercellular Signaling Peptides and Proteins / Q000235:genetics / Q000378:metabolism*; D000072101:Jagged-2 Protein; D008024:Ligands; D020935:MAP Kinase Signaling System; D008545:Melanoma / Q000378:metabolism / Q000473:pathology*; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D009361:Neoplasm Invasiveness / Q000473:pathology; D009362:Neoplasm Metastasis; D010766:Phosphorylation; D012333:RNA, Messenger / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction; D051880:Receptors, Notch / Q000502:physiology*; D015398:Signal Transduction; D000072056:Transcription Factor HES-1; D015854:Up-Regulation; D014604:Uveal Neoplasms / Q000378:metabolism / Q000473:pathology*
chemical_list: D051792:Basic Helix-Loop-Helix Proteins; D018398:Homeodomain Proteins; D036341:Intercellular Signaling Peptides and Proteins; D000072101:Jagged-2 Protein; D008024:Ligands; D008565:Membrane Proteins; D012333:RNA, Messenger; D051880:Receptors, Notch; D000072056:Transcription Factor HES-1; C490504:JAG2 protein, human; C078493:HES1 protein, human