Endothelial, platelet, and tissue factor-bearing microparticles in cancer patients with and without venous thromboembolism.
BACKGROUND
Cancer is a prothrombotic state, with an increased prevalence of venous thromboembolism (VTE). Microparticles (MPs) are sub-micron-sized vesicles derived from activated or apoptotic cells that may play a role in VTE, although evidence of this association is still limited.


OBJECTIVE
To evaluate the hypothesis that elevated numbers of endothelial (EMPs), platelets (PMPs), and Tissue Factor-bearing MPs (TF(+)MPs) in plasma may contribute to cancer-associated thrombosis.


METHODS
EMPs, PMPs and TF(+)MPs plasma levels were measured in 90 consecutive patients (cases) referred to our Department (30 with a first episode of unprovoked VTE; 30 with active cancer; 30 with a diagnosis of acute VTE associated with active cancer), and in a group of 90 healthy subjects (controls). MPs analyses were performed by flow-cytometry (Cytomics FC500).


RESULTS
Cases showed statistically significant higher (mean ± SD) circulating EMPs and PMPs plasma levels (920 ± 341 and 1221 ± 413 MP/μL, respectively) than controls (299 ± 102 and 495 ± 241 MP/μL; p<0.005). Moreover cancer patients (with and without VTE) showed higher (mean ± SD) TF(+)MPs (927 ± 415 MPs/μL) than controls (204 ± 112 MPs/μL; p<0.001). The subgroup of cancer patients plus VTE showed statistically significant higher TF(+)MPs plasma levels (1019 ± 656 MPs/μL) than cancer patients without VTE (755 ± 391 MPs/μL, p = 0.002). Multivariate analysis failed to show a significant association between elevated TF(+)MPs and VTE in cancer patients.


CONCLUSIONS
Our results suggest that MPs might be an important intermediate in the cascade of cellular injury and vascular dysfunctions underlying the process of thrombosis, particularly in cancer. Further clinical investigations are needed to confirm the precise role of MPs in predicting hypercoagulable state in patients with cancer.
Department of Cardiologic, Thoracic, and Vascular Sciences, 2nd Chair of Internal Medicine, University of Padua Medical School, Padua, Italy.
Elena
E
Campello
Luca
L
Spiezia
Claudia M
CM
Radu
Cristiana
C
Bulato
Monica
M
Castelli
Sabrina
S
Gavasso
Paolo
P
Simioni
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001792:Blood Platelets / Q000473:pathology; D016022:Case-Control Studies; D055252:Cell-Derived Microparticles / Q000473:pathology*; D042783:Endothelial Cells / Q000473:pathology; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000097:blood* / Q000473:pathology; D013925:Thromboplastin / Q000378:metabolism; D054556:Venous Thromboembolism / Q000097:blood* / Q000473:pathology
D013925:Thromboplastin