Fibrin-bearing microparticles: marker of thrombo-embolic events in pancreatic and colorectal cancers

Background Microparticles (MPs) are plasma membrane-derived extracellular vesicles present in the bloodstream. We have described a specific signature of MPs, called microparticulosome, in colorectal (CRC) and pancreatic (PC) cancers. We observed that levels of fibrin-bearing MPs were significantly increased in patients suffering from PC and CRC in comparison with control groups. Here, we hypothesised that fibrin-MPs may constitute a relevant biomarker of thrombosis associated with cancer. The objective was to compare the microparticulosome signature between patients presenting with thrombo-embolic event and those without. Methods Patients with CRC and PC were prospectively included and divided in those with thrombo-embolic events (Group A) and those without (Group B).MPs were analyzed by flow cytometer, combining the analysis of Annexin V-positive with characterization of their origin and determination of their procoagulant activities. D-dimer levels were measured in the same samples. Results We included 118 patients, divided in 19 patients with thrombo embolic event and 99 patients without. Fibrin-bearing MPs levels were significantly higher in presence of thrombo-embolic events, contrary to D-dimers levels. Fibrin-bearing MPs were more frequently produced by erythrocytes, endothelial cells or Ep-CAM+cells than platelets or leukocytes. Overall survival was shorter in case of thrombo-embolic events than without. The most frequent genes expressed by MPs derived from PC or CRC were implicated in metastatic diffusion of tumor cells, drug resistance, coagulation and inflammation. Conclusion Circulating MPs, particularly fibrin-bearing MPs, could be used as a new biomarker to predict cancer-associated thrombo-embolic events and poor survival.