title: Adrenomedullin is a cross-talk molecule that regulates tumor and mast cell function during human carcinogenesis.
abstract: We have previously demonstrated that adrenomedullin (AM) plays a critical role as an autocrine/paracrine tumor cell survival factor. We now present evidence that AM is an important regulator of mast cell (MC) function and that this modulation is potentially involved in tumor promotion. AM induced histamine or beta-hexosaminidase release from rat and human MCs through a receptor-independent pathway. AM was chemotactic for human MCs and stimulated mRNA expression of vascular endothelial growth factor, monocyte chemoattractant protein-1, and basic fibroblast growth factor in this cell type. Differentiated but not undifferentiated human MCs responded to hypoxic insult with elevated AM mRNA/protein expression. Using confocal microscopy, we identified AM-producing MCs in tumor infiltrates of human breast and lung cancer patients. In mixed culture assays the AM-producing human MC line HMC-1 augmented both anchorage-dependent and -independent growth of human lung cancer A549 cells, an effect that was suppressed by MC-targeted siRNA AM knockdown. Finally, HMC-1 cells induced in vivo angiogenesis as assessed by directed in vivo angiogenesis assay analysis; neutralizing anti-AM monoclonal antibody blocked this ability. Our collective data suggest a new role for AM as a cross-talk molecule that integrates tumor and MC communication, underlying a unique promotion mechanism of human cancers.
authors.affiliation: CCBB, CCR, National Cancer Institute, Bldg. 10, Rm., 12N226, Bethesda, MD 20892, USA. zudairee@mail.nih.gov
authors.forename: Enrique
authors.initials: E
authors.lastname: Zudaire
authors.forename: Alfredo
authors.initials: A
authors.lastname: Martínez
authors.forename: Mercedes
authors.initials: M
authors.lastname: Garayoa
authors.forename: Rubén
authors.initials: R
authors.lastname: Pío
authors.forename: Gurmeet
authors.initials: G
authors.lastname: Kaur
authors.forename: Michael R
authors.initials: MR
authors.lastname: Woolhiser
authors.forename: Dean D
authors.initials: DD
authors.lastname: Metcalfe
authors.forename: William A
authors.initials: WA
authors.lastname: Hook
authors.forename: Reuben P
authors.initials: RP
authors.lastname: Siraganian
authors.forename: Theresa A
authors.initials: TA
authors.lastname: Guise
authors.forename: John M
authors.initials: JM
authors.lastname: Chirgwin
authors.forename: Frank
authors.initials: F
authors.lastname: Cuttitta
mesh_terms: D053607:Adrenomedullin; D000818:Animals; D002450:Cell Communication / Q000502:physiology*; D045744:Cell Line, Tumor; D018932:Chemokine CCL2 / Q000378:metabolism; D002634:Chemotaxis, Leukocyte / Q000502:physiology; D016222:Fibroblast Growth Factor 2 / Q000096:biosynthesis; D006801:Humans; D008407:Mast Cells / Q000378:metabolism*; D018613:Microscopy, Confocal; D009369:Neoplasms / Q000378:metabolism*; D009389:Neovascularization, Pathologic / Q000378:metabolism; D010455:Peptides / Q000378:metabolism*; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D020239:Receptor Cross-Talk / Q000502:physiology*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D042461:Vascular Endothelial Growth Factor A / Q000096:biosynthesis
chemical_list: D018932:Chemokine CCL2; D010455:Peptides; D012333:RNA, Messenger; D042461:Vascular Endothelial Growth Factor A; D016222:Fibroblast Growth Factor 2; D053607:Adrenomedullin