title: Podosomes as novel players in endothelial biology.
abstract: Podosomes and invadopodia, collectively known as invadosomes, are specialized cell-matrix contacts with an inherent ability to degrade extracellular matrix. Their occurrence in either normal (podosomes) or cancer cells (invadopodia) is thus traditionally associated with cell invasiveness and tissue remodelling. These specialized micro-domains of the plasma membrane are characterized by enrichment of F-actin, cortactin and metalloproteases. Recent developments in the field show that, under some circumstances, vascular endothelial cells (ECs) can be induced to form this kind of peculiar structures. Cultured ECs contain either 0.5-1-μm-wide individual podosomes or 5 to 10 μm wide ring-like clusters of podosomes (podosome rosettes). The formation of individual podosomes or podosome rosettes in ECs can be induced by soluble factors, such as TGFβ, VEGF, TNFα or pharmacological agents, such as phorbol esters. Recently, the evidence of the existence of such structures in vascular endothelium has been provided by ex vivo observation. Endothelial podosome rosettes have recently been functionally linked to arterial remodelling and sprouting angiogenesis. Concerted efforts aim now at confirming the relevance of endothelial podosomes in these patho-physiological processes in vivo. In the current review, we will introduce some general considerations regarding ECs in the vascular system. From there on, we will review the various EC types where podosomes have been described and the state-of-art knowledge hitherto generated regarding endothelial podosome features.
authors.affiliation: Laboratory of Cell Migration, Candiolo Cancer Institute, FPO, IRCCS, Turin, Italy; Edwin L. Steele Laboratory for Tumor Biology, Department of Radiation Oncology, Harvard Medical School, Massachusetts General Hospital, Boston, MAUSA.
authors.forename: Giorgio
authors.initials: G
authors.lastname: Seano
authors.affiliation: European Institute of Chemistry and Biology, Université de Bordeaux, Pessac, France; INSERM, 1045, Université de Bordeaux, Bordeaux, France.
authors.forename: Thomas
authors.initials: T
authors.lastname: Daubon
authors.affiliation: European Institute of Chemistry and Biology, Université de Bordeaux, Pessac, France; INSERM, 1045, Université de Bordeaux, Bordeaux, France. Electronic address: e.genot@iecb.u-bordeaux.fr.
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Génot
authors.affiliation: Laboratory of Cell Migration, Candiolo Cancer Institute, FPO, IRCCS, Turin, Italy; Department of Oncology, University of Torino, Turin, Italy. Electronic address: luca.primo@ircc.it.
authors.forename: Luca
authors.initials: L
authors.lastname: Primo
mesh_terms: D000818:Animals; D022081:Cell Surface Extensions / Q000378:metabolism* / Q000648:ultrastructure; D042783:Endothelial Cells / Q000378:metabolism* / Q000648:ultrastructure; D006801:Humans; D007249:Inflammation / Q000378:metabolism / Q000473:pathology; D007511:Ischemia / Q000378:metabolism / Q000473:pathology; D009369:Neoplasms / Q000098:blood supply / Q000378:metabolism / Q000648:ultrastructure; D009389:Neovascularization, Pathologic / Q000378:metabolism / Q000473:pathology; D018919:Neovascularization, Physiologic
keywords: Endothelial cell; Invadosome; Podosome; Rosette; Tumour angiogenesis; Vascular sprouting