PB1204 - Synergistic role in accelerating clot formation and fibrin polymerisation of cancer cells and platelets: a thromboelastometric study

Background: The histological type and the aggressiveness of cancer cells as well as the acquisition of resistance to chemotherapy are significant predictors for the high risk of cancer associated thrombosis (CAT).The impact of cancer cells on clot formation kinetics and the qualitative characteristics of the clot has not been evaluated yet.

Aims: Analyze the variables which influence the kinetics and the qualitative characteristics of the clot after triggering thrombin generation by cells from pancreatic cancer (BXPC3), native and resistant breast cancer (MCF7 and MCF7R10) and multiple myeloma (RPMI-8226 and U266) associated with different risk of CAT.

Methods: Thromboelastometry, was used for the study of clot formation and firmness in whole blood (WB), platelet rich and platelet poor plasma (PRP and PPP respectively). Clotting time (CT), α-angle and maximum clot firmness (MCF) were analyzed.

Results: In PPP BXPC3 and MCF7 and MCF7R10 reduced TC, while RPMI8226 and U266 did not. All cancer lines increased α-angle compared to HUVECs, and did not significantly affect MCF.
In PRP, BXPC3 reduced the TC, in contrast to MCF7 and MCF7R10, myeloma cells prolonged it compared to HUVEC. BXPC3 increased the α-angle compared to HUVEC, unlike the other cell lines. Only myeloma cells decreased the MCF compared to HUVEC.
In WB BXPC3 and MCF7 decreased TC unlike MCF7R10 myeloma cells prolonged it. Only BXPC3 increased the α-angle. The presence of cancer cells decreased the MCF compared to the control (HUVEC).

Conclusion(s): This study demonstrates that cancer cells have an impact on clot formation kinetics without affecting clot firmness. The impact on clot formation kinetics is determined mainly by histological type. BXPC3 has a more pronounced effect on clot formation kinetics than Doxorubicin sensitive or resistant breast cancer cells, myeloma cells delay fibrin formation and polymerisation and decrease clot firmness. Platelets have a synergistic effect on the kinetics of clot formation.