IL-18 regulates melanoma VLA-4 integrin activation through a Hierarchized sequence of inflammatory factors.
Very late antigen-4 (VLA-4) is frequently overexpressed on melanoma cells contributing to inflammation-dependent metastasis. Melanoma cell adhesion to endothelium via VLA-4-vascular cell adhesion molecule-1 (VCAM-1) interaction was used to study VLA-4 activation during melanoma cell response to inflammation. Cooperation among major inflammatory mediators was analyzed in melanoma cells exposed to single inflammatory factors in the presence of inhibitors for other assayed mediators. A stepwise cascade of hierarchized molecules heterogeneously made and used during melanoma response to IL-18, induced hydrogen peroxide (H2O2), in turn activating VLA-4 and melanoma cell adhesion to endothelium. The cascade involved prostaglandin E2 (PGE2) production from melanoma induced by IL-18-dependent tumor necrosis factor-α (TNFα); next, PGE2-induced IL-1β via vascular endothelial growth factor (VEGF) secretion, which in turn induced VLA-4 activation via cyclooxygenase 2-dependent H2O2. This sequence operated in IL-18R/VLA-4/VEGF-expressing murine (B16) and human (A375 and 883) melanomas, but not in those without this phenotype. Separation of active VLA-4-expressing B16 melanoma cells through immobilized VCAM-1 verified their higher IL-18R/TNFR1/VEGFR2 expression and metastatic growth than inactive VLA-4-expressing cells. However, cooperation among melanoma cell sub-populations with heterogeneous cytokine receptor levels may occur through VLA-4-stimulating factors, leading to intratumoral amplification of metastatic potential. Therefore, expression of the VLA-4-stimulating factor sequence may help to predict melanoma prometastatic risk, and offers therapeutic targets for metastatic melanoma deactivation through VLA-4 activation blockade.
Innoprot SL, Bizkaia Technology Park, Derio, Bizkaia, Spain.
María
M
Valcárcel
Department of Cellular Biology and Histology, Basque Country University School of Medicine and Dentistry, Leioa, Bizkaia, Spain.
Teresa
T
Carrascal
Department of Cellular Biology and Histology, Basque Country University School of Medicine and Dentistry, Leioa, Bizkaia, Spain.
Olatz
O
Crende
CEU-San Pablo University and HM-Hospitals School of Medicine, Institute of Applied Molecular Medicine (IMMA), Boadilla del Monte, Madrid, Spain. Electronic address: fernando.vidalvanaclocha@ceu.es.
Fernando
F
Vidal-Vanaclocha
D000818:Animals; D002448:Cell Adhesion / Q000276:immunology; D045744:Cell Line, Tumor; D006801:Humans; D007249:Inflammation / Q000276:immunology / Q000378:metabolism; D039041:Integrin alpha4beta1 / Q000276:immunology* / Q000378:metabolism; D020382:Interleukin-18 / Q000276:immunology* / Q000378:metabolism; D008099:Liver / Q000166:cytology; D008113:Liver Neoplasms / Q000453:epidemiology / Q000276:immunology / Q000556:secondary; D008297:Male; D008545:Melanoma / Q000453:epidemiology / Q000276:immunology / Q000556:secondary; D051379:Mice; D008810:Mice, Inbred C57BL; D008819:Mice, Nude; D061251:Primary Cell Culture; D053724:Receptors, Interleukin-18 / Q000235:genetics / Q000276:immunology; D047888:Receptors, Tumor Necrosis Factor, Type I / Q000235:genetics / Q000276:immunology; D012307:Risk Factors; D012878:Skin Neoplasms / Q000453:epidemiology / Q000276:immunology / Q000473:pathology; D040301:Vascular Endothelial Growth Factor Receptor-2 / Q000235:genetics / Q000276:immunology
D039041:Integrin alpha4beta1; D020382:Interleukin-18; D053724:Receptors, Interleukin-18; D047888:Receptors, Tumor Necrosis Factor, Type I; D040301:Vascular Endothelial Growth Factor Receptor-2