Differential Procoagulant Phenotype of Pancreatic and Breast Cancer Cells Related to Different Tissue Factor Activity.

Tissue factor (TF) expressed by some cancer cells is implicated in metastasis and angiogenesis. The influence of cancer cells on blood coagulation has not been adequately studied. We evaluated the procoagulant potential of pancreatic and breast cancer cells (BXPC3 and MCF7 cell lines respectively) when they are in contact with human platelet-poor plasma (PPP). At 40% and 90% confluence, adhesive cultures of BXPC3 and MCF7 cells were treated with trypsine according to standardized procedure and cancer cells were suspended in normal human platelet poor plasma (PPP) at increasing concentrations. Coagulation was triggered by CaCl₂ addition and thrombin generation (TG) was monitored using the Calibrated Automated Thrombogram-Thrombinoscope® (Biodis-France). In some experiments, cancer cells were incubated for 30 min with a polyclonal specific anti-TF antibody (American Diagnostics). Cancer cells accelerated TG by decreasing significantly lag-time, and time to Peak of thrombin (ttPeak) but they did not significantly influence the endogenous thrombin potential. BXPC3 had significantly more potent procoagulant activity compared to MCF7 cells. Incubation of cancer cells with anti-TF antibody resulted in a concentration dependent inhibition of their procoagulant effect. The IC50 of the anti-TF antibody for TG induced by BXPC3 was about 10-fold higher to that for MCF7. Pancreatic cancer cells (BXPC3) and breast cancer cells (MCF7) accelerate thrombin generation of human plasma in a TF-dependent manner. BXPC3 have more potent procoagulant activity than MCF7 probably due to increased TF expression.