title: A cancer cell metalloprotease triad regulates the basement membrane transmigration program.
abstract: Carcinoma cells initiate the metastatic cascade by inserting invasive pseudopodia through breaches in the basement membrane (BM), a specialized barrier of cross-linked, extracellular matrix macromolecules that underlies epithelial cells and ensheaths blood vessels. While BM invasion is the sine qua non of the malignant phenotype, the molecular programs that underlie this process remain undefined. To identify genes that direct BM remodeling and transmigration, we coupled high-resolution electron microscopy with an ex vivo model of invasion that phenocopies the major steps observed during the transition of carcinoma in situ to frank malignancy. Herein, a triad of membrane-anchored proteases, termed membrane type-1, type-2, and type-3 metalloproteinases, are identified as the triggering agents that independently confer cancer cells with the ability to proteolytically efface the BM scaffolding, initiate the assembly of invasive pseudopodia, and propagate transmigration. These studies characterize the first series of gene products capable of orchestrating the entire BM remodeling program that distinguishes the carcinomatous phenotype.
authors.affiliation: Division of Molecular Medicine and Genetics, Department of Internal Medicine, Life Sciences Institute, University of Michigan, Ann Arbor, Michigan 48109, USA.
authors.forename: Kevin
authors.initials: K
authors.lastname: Hotary
authors.forename: Xiao-Yan
authors.initials: XY
authors.lastname: Li
authors.forename: Edward
authors.initials: E
authors.lastname: Allen
authors.forename: Susan L
authors.initials: SL
authors.lastname: Stevens
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Weiss
mesh_terms: D000818:Animals; D001485:Basement Membrane / Q000201:enzymology / Q000502:physiology* / Q000648:ultrastructure; D019556:COS Cells; D002460:Cell Line; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000502:physiology; D002522:Chlorocebus aethiops; D024141:Collagen Type IV / Q000378:metabolism; D005109:Extracellular Matrix / Q000378:metabolism / Q000648:ultrastructure; D006801:Humans; D053511:Matrix Metalloproteinase 14 / Q000235:genetics / Q000378:metabolism; D053517:Matrix Metalloproteinase 15 / Q000235:genetics / Q000378:metabolism; D053513:Matrix Metalloproteinase 16 / Q000235:genetics / Q000378:metabolism; D053504:Matrix Metalloproteinases, Membrane-Associated / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D009154:Mutation / Q000235:genetics; D009361:Neoplasm Invasiveness; D009369:Neoplasms / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology; D034741:RNA, Small Interfering / Q000235:genetics; D051381:Rats; D019714:Tissue Inhibitor of Metalloproteinases / Q000378:metabolism
chemical_list: D024141:Collagen Type IV; D034741:RNA, Small Interfering; D019714:Tissue Inhibitor of Metalloproteinases; D053517:Matrix Metalloproteinase 15; D053513:Matrix Metalloproteinase 16; D053504:Matrix Metalloproteinases, Membrane-Associated; D053511:Matrix Metalloproteinase 14