title: Heparanase degrades syndecan-1 and perlecan heparan sulfate: functional implications for tumor cell invasion.
abstract: Heparanase (HPSE-1) is involved in the degradation of both cell-surface and extracellular matrix (ECM) heparan sulfate (HS) in normal and neoplastic tissues. Degradation of heparan sulfate proteoglycans (HSPG) in mammalian cells is dependent upon the enzymatic activity of HPSE-1, an endo-beta-d-glucuronidase, which cleaves HS using a specific endoglycosidic hydrolysis rather than an eliminase type of action. Elevated HPSE-1 levels are associated with metastatic cancers, directly implicating HPSE-1 in tumor progression. The mechanism of HPSE-1 action to promote tumor progression may involve multiple substrates because HS is present on both cell-surface and ECM proteoglycans. However, the specific targets of HPSE-1 action are not known. Of particular interest is the relationship between HPSE-1 and HSPG, known for their involvement in tumor progression. Syndecan-1, an HSPG, is ubiquitously expressed at the cell surface, and its role in cancer progression may depend upon its degradation. Conversely, another HSPG, perlecan, is an important component of basement membranes and ECM, which can promote invasive behavior. Down-regulation of perlecan expression suppresses the invasive behavior of neoplastic cells in vitro and inhibits tumor growth and angiogenesis in vivo. In this work we demonstrate the following. 1) HPSE-1 cleaves HS present on the cell surface of metastatic melanoma cells. 2) HPSE-1 specifically degrades HS chains of purified syndecan-1 or perlecan HS. 3) Syndecan-1 does not directly inhibit HPSE-1 enzymatic activity. 4) The presence of exogenous syndecan-1 inhibits HPSE-1-mediated invasive behavior of melanoma cells by in vitro chemoinvasion assays. 5) Inhibition of HPSE-1-induced invasion requires syndecan-1 HS chains. These results demonstrate that cell-surface syndecan-1 and ECM perlecan are degradative targets of HPSE-1, and syndecan-1 regulates HPSE-1 biological activity. This suggest that expression of syndecan-1 on the melanoma cell surface and its degradation by HPSE-1 are important determinants in the control of tumor cell invasion and metastasis.
authors: Department of Comparative Biomedical Sciences-SVM, Louisiana State University, Baton Rouge, Louisiana 70803, USA.
authors: Jane
authors: J
authors: Reiland
authors: Ralph D
authors: RD
authors: Sanderson
authors: Marian
authors: M
authors: Waguespack
authors: Steven A
authors: SA
authors: Barker
authors: Robert
authors: R
authors: Long
authors: Daniel D
authors: DD
authors: Carson
authors: Dario
authors: D
authors: Marchetti
mesh_terms: D000230:Adenocarcinoma; D000818:Animals; D002462:Cell Membrane / Q000737:chemistry; D015179:Colorectal Neoplasms; D005109:Extracellular Matrix / Q000737:chemistry; D005966:Glucuronidase / Q000037:antagonists & inhibitors / Q000378:metabolism*; D019812:Heparan Sulfate Proteoglycans / Q000378:metabolism* / Q000494:pharmacology; D006497:Heparan Sulfate / Q000378:metabolism* / Q000494:pharmacology; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008545:Melanoma / Q000473:pathology / Q000648:ultrastructure; D008562:Membrane Glycoproteins / Q000378:metabolism* / Q000494:pharmacology; D051379:Mice; D009361:Neoplasm Invasiveness / Q000503:physiopathology* / Q000517:prevention & control; D009362:Neoplasm Metastasis; D011509:Proteoglycans / Q000378:metabolism* / Q000494:pharmacology; D011994:Recombinant Proteins / Q000378:metabolism; D013379:Substrate Specificity; D053668:Syndecan-1; D053667:Syndecans; D014407:Tumor Cells, Cultured; D000099175:Heparanase
chemical_list: D005966:Glucuronidase; D019812:Heparan Sulfate Proteoglycans; D006497:Heparan Sulfate; D008562:Membrane Glycoproteins; D011509:Proteoglycans; D011994:Recombinant Proteins; D053668:Syndecan-1; D053667:Syndecans; D000099175:Heparanase; C508241:SDC1 protein, human; C508242:Sdc1 protein, mouse; C071927:perlecan