Connective tissue growth factor is a substrate of ADAM28.
ADAM28, a member of the ADAM (a disintegrin and metalloproteinase) gene family, is over-expressed by carcinoma cells and the expression correlates with carcinoma cell proliferation and progression in human lung and breast carcinomas. However, information about substrates of ADAM28 is limited. We screened interacting molecules of ADAM28 in human lung cDNA library by yeast two-hybrid system and identified connective tissue growth factor (CTGF). Binding of CTGF to proADAM28 was demonstrated by yeast two-hybrid assay and protein binding assay. ADAM28 cleaved CTGF in dose- and time-dependent manners at the Ala(181)-Tyr(182) and Asp(191)-Pro(192) bonds in the hinge region of the molecule. ADAM28 selectively digested CTGF in the complex of CTGF and vascular endothelial growth factor(165) (VEGF(165)), releasing biologically active VEGF(165) from the complex. RT-PCR and immunohistochemical analyses demonstrated that ADAM28, CTGF and VEGF are commonly co-expressed in the breast carcinoma tissues. These data provide the first evidence that CTGF is a novel substrate of ADAM28 and suggest that ADAM28 may promote VEGF(165)-induced angiogenesis in the breast carcinomas by the CTGF digestion in the CTGF/VEGF(165) complex.
Department of Pathology, School of Medicine, Keio University, Tokyo, Japan.
Satsuki
S
Mochizuki
Rena
R
Tanaka
Masayuki
M
Shimoda
Junko
J
Onuma
Yutaka
Y
Fujii
Hiromitsu
H
Jinno
Yasunori
Y
Okada
D051722:ADAM Proteins / Q000235:genetics / Q000378:metabolism*; D001943:Breast Neoplasms / Q000098:blood supply* / Q000201:enzymology; D002277:Carcinoma / Q000098:blood supply* / Q000201:enzymology; D045744:Cell Line, Tumor; D055513:Connective Tissue Growth Factor / Q000235:genetics / Q000378:metabolism*; D005260:Female; D006801:Humans; D009389:Neovascularization, Pathologic / Q000201:enzymology*; D013379:Substrate Specificity; D020798:Two-Hybrid System Techniques; D042461:Vascular Endothelial Growth Factor A / Q000494:pharmacology
C526317:CCN2 protein, human; D042461:Vascular Endothelial Growth Factor A; D055513:Connective Tissue Growth Factor; D051722:ADAM Proteins; C410224:ADAM28 protein, human