title: Tumor angiogenesis is caused by single melanoma cells in a manner dependent on reactive oxygen species and NF-κB.
abstract: Melanomas have a high angiogenic potential, but respond poorly to medical treatment and metastasize very early. To understand the early events in tumor angiogenesis, animal models with high tumor resolution and blood vessel resolution are required, which provide the opportunity to test the ability of small molecule inhibitors to modulate the angiogenic tumor program. We have established a transgenic melanoma angiogenesis model in the small laboratory fish species Japanese medaka. Here, pigment cells are transformed by an oncogenic receptor tyrosine kinase in fish expressing GFP throughout their vasculature. We show that angiogenesis occurs in a reactive oxygen species (ROS)- and NF-κB-dependent, but hypoxia-independent manner. Intriguingly, we observed that blood vessel sprouting is induced even by single transformed pigment cells. The oncogenic receptor as well as human melanoma cells harboring other oncogenes caused the production of pro-angiogenic factors, most prominently angiogenin, through NF-κB signaling. Inhibiting NF-κB prevented tumor angiogenesis and led to the regression of existing tumor blood vessels. In conclusion, our high-resolution medaka melanoma model discloses that ROS and NF-κB signaling from single tumor cells causes hypoxia-independent angiogenesis, thus, demonstrating that the intrinsic malignant tumor cell features are sufficient to initiate and maintain a pro-angiogenic signaling threshold.
authors.affiliation: Department of Physiological Chemistry I, Biocenter, Am Hubland, University of Wurzburg, Wurzburg, Germany.
authors.forename: Maximilian K
authors.initials: MK
authors.lastname: Schaafhausen
authors.forename: Wan-Jen
authors.initials: WJ
authors.lastname: Yang
authors.forename: Lazaro
authors.initials: L
authors.lastname: Centanin
authors.forename: Joachim
authors.initials: J
authors.lastname: Wittbrodt
authors.forename: Anja
authors.initials: A
authors.lastname: Bosserhoff
authors.forename: Andreas
authors.initials: A
authors.lastname: Fischer
authors.forename: Manfred
authors.initials: M
authors.lastname: Schartl
authors.forename: Svenja
authors.initials: S
authors.lastname: Meierjohann
mesh_terms: D000818:Animals; D015687:Cell Hypoxia; D045744:Cell Line, Tumor; D002470:Cell Survival; D029941:Fish Proteins / Q000494:pharmacology; D020869:Gene Expression Profiling; D049452:Green Fluorescent Proteins / Q000235:genetics; D057809:HEK293 Cells; D061307:Human Umbilical Vein Endothelial Cells; D006801:Humans; D008545:Melanoma / Q000098:blood supply* / Q000378:metabolism; D051379:Mice; D009389:Neovascularization, Pathologic / Q000378:metabolism*; D009990:Oryzias; D034622:RNA Interference; D034741:RNA, Small Interfering; D017382:Reactive Oxygen Species / Q000378:metabolism*; D020794:Receptor Protein-Tyrosine Kinases / Q000494:pharmacology; D012259:Ribonuclease, Pancreatic / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction; D019715:Tissue Inhibitor of Metalloproteinase-1 / Q000235:genetics / Q000378:metabolism; D051996:Transcription Factor RelA / Q000378:metabolism*
chemical_list: D029941:Fish Proteins; D034741:RNA, Small Interfering; D017382:Reactive Oxygen Species; C498144:Rela protein, mouse; C560822:TIMP1 protein, human; D019715:Tissue Inhibitor of Metalloproteinase-1; D051996:Transcription Factor RelA; D049452:Green Fluorescent Proteins; D020794:Receptor Protein-Tyrosine Kinases; C077101:Xmrk protein, Xiphophorus; C046366:angiogenin; D012259:Ribonuclease, Pancreatic
keywords: Melanoma; NF-κB; ROS; Tumor angiogenesis