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Membrane type‐1 matrix metalloproteinase stimulates tumour cell‐induced platelet aggregation: role of receptor glycoproteins

2004; Wiley; Volume: 141; Issue: 2 Linguagem: Inglês

10.1038/sj.bjp.0705606

1476-5381

David Alonso‐Escolano, Alex Y. Strongin, Ada W.Y. Chung, Elena I. Deryugina, Marek W. Radomski,

Platelet Disorders and Treatments

Matrix metalloproteinase‐2 (MMP‐2) plays a role in agonist‐ and tumour cell‐induced platelet aggregation (TCIPA). MMP‐2 is synthesized as a proenzyme and is activated at the cell surface by membrane type‐1 matrix metalloproteinase (MT1‐MMP, MMP‐14). The significance of tumour cell‐associated MT1‐MMP for TCIPA was investigated using human breast carcinoma MCF7 cells stably coexpressing the integrin α v β 3 with MT1‐MMP, cells expressing α v β 3 alone and mock‐transfected cells. Western blot and zymography confirmed that α v β 3/MT1‐MMP cells expressed MT1‐MMP and efficiently processed proMMP‐2 to MMP‐2. Aggregometry, phase‐contrast and transmission electron microscopy and flow cytometry were used to characterize TCIPA induced by MCF7 cell lines. The aggregating potency of cells was: α v β 3/MT1‐MMP > α v β 3=mock cells, as shown by aggregometry and phase‐contrast microscopy. Electron microscopy revealed close, membrane–membrane interactions between activated platelets and α v β 3/MT1‐MMP cells during TCIPA. Inhibition of MMP‐2 with the neutralizing anti‐MMP‐2 antibody (5 μ g ml −1 ) and o ‐phenanthroline (100 μ M ) reduced aggregation induced by α v β 3/MT1‐MMP cells. TCIPA induced by α v β 3/MT1‐MMP cells was also reduced by inhibiting the generation and actions of ADP with apyrase (250 μ g ml −1 ) and 2‐methylthio‐AMP (2‐MeSAMP) (30 μ M ), but not N 6 ‐methyl‐2′‐deoxyadenosine‐3′,5′‐bisphosphate (MRS2179) (30 μ M ). Flow cytometry demonstrated that TCIPA enhanced expression of glycoprotein (GP) Ib and IIb/IIIa receptors not only on platelets but also on breast cancer cells. Thus, (a) human breast carcinoma cell surface‐associated MT1‐MMP, via activating proMMP‐2, stimulates TCIPA; (b) ADP amplifies the effects of MMPs via stimulation of P2Y 12 receptors and (c) both tumour‐ and platelet‐derived GPIb and GPIIb/IIIa are involved in the aggregatory effects of MT1‐MMP. British Journal of Pharmacology (2004) 141 , 241–252. doi: 10.1038/sj.bjp.0705606