Thrombin stimulates melanoma tumor‐cell binding to endothelial cells and subendothelial matrix

Abstract

Thrombin has been shown to activate tumor-cell adhesion to platelets, fibronectin and von Willebrand factor 2-to 3-fold in vitro, and enhance metastasis 10-to 156-fold in vivo. We therefore elected to determine whether thrombin binds to tumor cells and whether thrombin-treated tumor cells enhance their adhesion to endothelial cells, the first barrier to tumor invasion and metastasis. Thrombin-treated human and hamster melanoma cells enhanced their adhesion to bovine aortic endothelial cells 2. I -to 2.3-fold, respectively. Similar results were obtained with bovine capillary endothelial cells. Thrombin activation of tumor cells was rapid, reaching its peak 15 rnin after thrombin activation: and transient, declining to baseline levels by 60 min. '"1-thrombin bound to both SK-Mel-28 and HM-29 cells in a saturation-dependent manner, was inhibitable by unlabelled thrombin, and could be 90% washed away with buffer following 30 min of incubation. Electron microscopy of tumor cells bound to fibronectin-coated millipore filters revealed adhesion of naive as well as thrombin- We have recently reported that thrombin-treated tumor cells enhance their adhesion to naive platelets, fibronectin and von Willebrand factor 2-to 3-fold in vitro; and enhance experimental pulmonary metastasis 10-to 156-fold in vivo (Nierodzik et al., 1992). Similar results were obtained with thrombin-activated platelets in vitro and thrombin injected intravenously with tumor cells (Nierodzik et al., 1991). Because the effect of thrombin on in vivo metastasis was considerably greater than its effect on tumor-cell adhesion to platelets and adhesive ligands, we considered the possibility that thrombintreated tumor cells might also enhance their adhesiveness to endothelial cells, an important host barrier against tumor-cell invasion. This proved to be indeed the case.The present report documents saturation binding of thrombin to tumor cells, enhanced adhesion of cells from 2 different thrombin-treated melanoma lines (HM29 and SK Me1 28) to bovine aortic and capillary endothelial cells, as well as the transient adhesive effect of thrombin treatment (peaking at 15 min and disappearing at 60 min). MATERIAL AND METHODS Tumor-cell linesSK Me1 28 is a human melanoma cell line obtained from the ATCC (Rockville, MD). HM-29 is a hamster melanoma, kindly supplied by Dr. J-C. Bystryn of New York University Medical School. Both were grown in RPMI (GTBCO, Grand Island, NY) supplemented with 1% penicillin-streptomycin, 2% glutamine, 1% non-essential amino acids and 10% FCS (GIBCO) in 50-ml plastic tissue-culture flasks. Cells were harvested at subconfluence with Trypsin-EDTA or EDTA alone. Monoclonal antibodiesAnti-pl (AIAS) was a gift from Dr. M. Hemler, DanaFarber Cancer Institute, Boston, MA. Anti-a3P1 (PB15) was a gift from Dr. W.G. Carter. Anti-qP, (LM609) was a gift from Dr. Cheresh, Scripps Clinic, La Jolla, CA. Anti433 (LK-2 against platelet GPIIIa) was prepared in our laboratory. Rat anti-a5 (PlE5) was a gift from Dr. C. Damsky, UCSF, San Francisco, CA, and a...

Differential effects of anticoagulants on tumor development of mouse cancer cell lines B16, K1735 and CT26 in lung

“…Thrombin binds PAR-1 and mediates increased invasiveness and metastatic potential of cancer cells [33][34][35] and enhanced cancer cell adhesion to platelets [36][37][38], endothelial cells [39], fibronectin and Von Willebrand factor [12,37]. Inhibition of thrombin by Hirudin may switch off PAR-1 signalling resulting in decreased tumor growth.…”

Bax-derived membrane-active peptides act as potent and direct inducers of apoptosis in cancer cells

“…TS/A-pc mice mammary carcinoma cells were cultured in RPMI 1640 supplemented with 1% glutamine, 10% FBS, 50 U/ml penicillin, and 50 g/ml streptomycin at 37°C in a humidified 95% air, 5% CO 2 atmosphere. These cells are integrin vb3 positive (Klepfish et al, 1993;Sancey et al, 2007).…”

Role of thrombin as a tumor growth factor

“…3 However, a cause and effect relationship between in vivo thrombin generation, thrombosis and cancer was not rigorously established until ∼18 years ago when Nierodzik et al 4 first reported enhanced murine experimental pulmonary metastasis following the intravenous injection of minute concentrations of thrombin (titered not to reduce the platelet count). This group also demonstrated enhanced adhesion of tumor cells to thrombintreated platelets with as little as 0.001-0.01 U/mL of thrombin exposure for 1 h. 4 In ensuing publications they then observed that thrombin has a protease activated receptor (PAR)-1 binding site on tumor cells 5 and that thrombin can activate tumor cells to adhere more avidly to platelets, fibronectin and von Willebrand factor 6 and endothelial cells 7 implanting and growing. However experiments which measured the effect of hirudin (an exquisitely potent inhibitor of thrombin) on spontaneous metastasis of a highly aggressive murine breast cancer (4T1) tumor cell line following implantation of tumor into the flank demonstrated that endogenous thrombin significantly contributed to tumor implantation, growth, seeding, spontaneous metastasis and death.…”

“…Hematol/Oncol N Amer 1997; 11:71. pulmonary metastasis. 6,8 Most tumor cells studied contain the thrombin PAR-1, [5][6][7][8][9] which is rate-limiting for tumor adhesion to fibronectin 10 as well as experimental metastasis: as demonstrated by transfection experiments in B16F10 melanoma cells, 10 as well as pathophysiologic studies with PAR-1 overexpression in invasive breast carcinoma. 11 Other studies have revealed that thrombin, in the presence of serum can induce tumor cell growth in vitro as well as in vivo.…”