Role of platelets, thrombin, integrin IIb-IIIa, fibronectin and von Willebrand factor on tumor adhesion in vitro and metastasis in vivo

M. L. Nierodzik, A. Klepfish, S. Karpatkin

Research output: Contribution to journalArticlepeer-review

Abstract

The role of platelets and thrombin was examined in tumor cell adhesion in vitro and metastasis in vivo. Adhesion of tumor cells to platelets was inhibited by agents inhibiting platelet integrin IIb-IIIa receptor occupancy (MoAb 10E5 and tetrapeptide RGDS) as well as IIb-IIIa ligands (polyclonal antibodies against fibronectin and von Willebrand factor (vWF)). In vivo murine experimental pulmonary metastasis (tail vein injection) could be inhibited by antibody-induced induction of thrombocytopenia and reconstituted by simultaneous injection of human platelets. Preincubation of human platelets with MoAb 10E5 (vs IIb-IIIa) inhibited reconstitution of metastasis. Thrombin activates tumor cell adhesion to platelets by activating platelets as well as tumor cells. Thrombin-activated tumor cells also enhance their adhesion to endothelial cells as well as adhesive ligands fibronectin and vWF. Experimental pulmonary metastasis is enhanced 4-400 fold by preinfusion of thrombin into mice or 10-160 fold by prior treatment of tumor cells with thrombin. The in vitro and in vivo effects of thrombin were mimicked by thrombin receptor activation pep tides SFLLRNPNDKYEPF and SFLLRN. Nine of nine tumor cell lines have the seven transmembrane spanning thrombin receptor detected by the polymerase chain reaction. Thus, both platelets and thrombin contribute to experimental tumor metastasis by fostering and enhancing IIb-IIIa integrin platelet interaction with tumor cells. Since many tumor cells generate thrombin, it is proposed that tumor cells may autoactivate a metastatic phenotype.

Original languageEnglish
Pages (from-to)282-290
Number of pages9
JournalThrombosis and Haemostasis
Volume74
Issue number1
DOIs
StatePublished - 1995
Externally publishedYes

Fingerprint

Dive into the research topics of 'Role of platelets, thrombin, integrin IIb-IIIa, fibronectin and von Willebrand factor on tumor adhesion in vitro and metastasis in vivo'. Together they form a unique fingerprint.

Cite this