Brain-enriched hyaluronan binding (BEHAB)/brevican cleavage in a glioma cell line is mediated by a disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS) family member.
Brain-enriched hyaluronan binding (BEHAB)/brevican is a brain-specific extracellular matrix protein containing a cleavage site between Glu(395)-Ser(396), which bears remarkable homology to the "aggrecanase" site in the cartilage proteoglycan aggrecan. Expression of BEHAB/brevican is dramatically increased in human gliomas, notoriously invasive tumors. Recently, we showed that the rat 9L gliosarcoma cell line, which does not express BEHAB/brevican and forms non-invasive tumors when grown as intracranial grafts, can form invasive tumors when transfected with a 5' cDNA fragment of BEHAB/brevican, but not when transfected with the full-length cDNA. In marked contrast, the highly invasive CNS-1 glioma cell line expresses and cleaves BEHAB/brevican protein when grown as an intracranial graft. These results suggest that both synthesis and cleavage of BEHAB/brevican protein may play a role in the invasiveness of gliomas. We report here, using an antibody developed to the neoepitope created by BEHAB/brevican cleavage at the Glu(395)-Ser(396) site, that the CNS-1 cells are able to cleave the protein in vitro. We characterized the CNS-1-derived cleavage activity by assaying its ability to cleave BEHAB/brevican proteoglycan, and determined that the enzyme is a constitutively expressed, secreted activity. Using a variety of protease inhibitors, reverse transcriptase-polymerase chain reaction, and specific antibodies, we determined that this activity is likely to be a member of the ADAMTS family of metalloproteinases, specifically ADAMTS4. These results suggest a novel function for ADAMTS family members in BEHAB/brevican cleavage and glioma and indicate that inhibition of ADAMTS in glioma may provide a novel therapeutic strategy.
Matthews
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RT
Section of Neurobiology, Yale University School of Medicine, New Haven, Connecticut 06520, USA. russell.matthews@yale.edu
Gary
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SC
Zerillo
C
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Pratta
M
M
Solomon
K
K
Arner
E C
EC
Hockfield
S
S
D051722:ADAM Proteins / Q000037:antagonists & inhibitors / Q000378:metabolism*; D000071121:ADAMTS4 Protein; D000818:Animals; D001483:Base Sequence; D001921:Brain / Q000378:metabolism*; D058581:Brevican; D011508:Chondroitin Sulfate Proteoglycans / Q000378:metabolism*; D017931:DNA Primers; D019483:Disintegrins / Q000378:metabolism*; D005910:Glioma / Q000378:metabolism / Q000473:pathology; D006801:Humans; D006820:Hyaluronic Acid / Q000378:metabolism*; D006868:Hydrolysis; D037181:Lectins, C-Type; D008666:Metalloendopeptidases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D009419:Nerve Tissue Proteins / Q000378:metabolism*; D011233:Precipitin Tests; D011480:Protease Inhibitors / Q000494:pharmacology; D051381:Rats; D019699:Thrombospondins / Q000737:chemistry*; D014162:Transfection; D014407:Tumor Cells, Cultured
C546938:BCAN protein, human; C546939:Bcan protein, rat; D058581:Brevican; D011508:Chondroitin Sulfate Proteoglycans; D017931:DNA Primers; D019483:Disintegrins; D037181:Lectins, C-Type; D009419:Nerve Tissue Proteins; D011480:Protease Inhibitors; D019699:Thrombospondins; D006820:Hyaluronic Acid; D051722:ADAM Proteins; C571365:ADAMTS4 protein, rat; D008666:Metalloendopeptidases; D000071121:ADAMTS4 Protein