thromboplastin and Hemangiosarcoma

Hypercoagulability is a common paraneoplastic complication in dogs with various malignant tumors. Importantly, tissue factor procoagulant activity (TF-PCA) induced by TF-bearing microparticles (TF-MPs) is associated with hypercoagulability in human patients with cancer. However, TF-PCA in tumor cells and the association between circulating TF-MPs and hypercoagulability in dogs with malignant tumors remain poorly understood. Therefore, the present study was conducted to evaluate the TF-PCA in various types of canine tumor cell lines and plasma in dogs with malignant tumors. Mammary gland tumor, hemangiosarcoma, and malignant melanoma cell lines, but not lymphoma cell lines, expressed TF on their surfaces and showed cellular surface and MP-associated TF-PCA. The plasma TF-PCA was elevated in some dogs that naturally developed such tumors. No significant difference was observed in plasma TF-PCA between the disseminated intravascular coagulation (DIC) group (median: 43.40; range: 3.47-85.19; n=5) and non-DIC group (median: 7.73; range: 1.70-16.13; n=12). However, plasma TF-PCA was remarkably elevated in three of five dogs with DIC. To the best of our knowledge, this is the first study to evaluate plasma TF-PCA in dogs with malignant tumors. Further studies must be conducted to determine the cellular origin of TF-MPs and the efficacy of plasma TF-PCA as a biomarker of DIC in dogs with malignant tumors.

Topics: Animals; Cell Line, Tumor; Cell-Derived Microparticles; Dog Diseases; Dogs; Female; Flow Cytometry; Hemangiosarcoma; Lymphoma; Mammary Neoplasms, Animal; Melanoma; Neoplasms; Thromboplastin

OBJECTIVE To evaluate expression of procoagulant tissue factor (TF) by canine hemangiosarcoma cells in vitro. SAMPLES 4 canine hemangiosarcoma cell lines (SB-HSA [mouse-passaged cutaneous tumor], Emma [primary metastatic brain tumor], and Frog and Dal-1 [primary splenic tumors]) and 1 nonneoplastic canine endothelial cell line (CnAoEC). PROCEDURES TF mRNA and TF antigen expression were evaluated by quantitative real-time PCR assay and flow cytometry, respectively. Thrombin generation was measured in canine plasma and in coagulation factor-replete or specific coagulation factor-deficient human plasma by calibrated automated thrombography. Corn trypsin inhibitor and annexin V were used to examine contributions of contact activation and membrane-bound phosphatidylserine, respectively, to thrombin generation. RESULTS All cell lines expressed TF mRNA and antigen, with significantly greater expression of both products in SB-HSA and Emma cells than in CnAoEC. A greater percentage of SB-HSA cells expressed TF antigen, compared with other hemangiosarcoma cell lines. All hemangiosarcoma cell lines generated significantly more thrombin than did CnAoEC in canine or factor-replete human plasma. Thrombin generation induced by SB-HSA cells was significantly lower in factor VII-deficient plasma than in factor-replete plasma and was abolished in factor X-deficient plasma; residual thrombin generation in factor VII-deficient plasma was abolished by incubation of cells with annexin V. Thrombin generation by SB-HSA cells was unaffected by the addition of corn trypsin inhibitor. CONCLUSIONS AND CLINICAL RELEVANCE Hemangiosarcoma cell lines expressed procoagulant TF in vitro. Further research is needed to determine whether TF can be used as a biomarker for hemostatic dysfunction in dogs with hemangiosarcoma.

Topics: Animals; Biomarkers; Brain Neoplasms; Cell Line, Tumor; Dog Diseases; Dogs; Flow Cytometry; Hemangiosarcoma; Mice; Real-Time Polymerase Chain Reaction; RNA, Messenger; Skin Neoplasms; Splenic Neoplasms; Thromboplastin

The objective of this study is to report the use of thromboelastography as a diagnostic tool for the hyperfibrinolytic phase of disseminated intravascular coagulopathy in a dog with metastatic haemangiosarcoma. We established a cytological (i.e. fine needle aspirate) and histopathological (i.e. excisional surgical biopsy) diagnosis of haemangiosarcoma in a 10-year-old male castrated Bichon Frise with multiple dark purple dermoepidermal nodules on the ventral abdomen and medial stifle areas, multiple small pulmonary nodules and a solitary liver mass. The dog was treated with chemotherapy (AC protocol). Forty-nine days after completion of four treatment cycles, the dog was presented for recheck. Complete blood count revealed anaemia and mild thrombocytopenia. Chemistry profile showed no significant abnormalities. Analysis of haemostasis consisted of prolonged clotting times (prothrombin time, activated partial thromboplastin time), mild hypofibrinogenaemia and increased D-dimers. A presumptive diagnosis of disseminated intravascular coagulopathy was made. A re-calcified thromboelastography was simultaneously done to confirm the coagulopathy. Thromboelastographic tracings correlated with the plasma-based test results showing hypocoagulability (prolonged clotting times and prolonged thromboelastography clot kinetics; weaker clot with decreased fibrinogen levels, platelet count and lower thromboelastography tracing amplitude) and hyperfibrinolysis (increased D-dimers and increased D-dimers and increased thromboelastography lysis parameters). Based on these results, the dog was considered to be in the hyperfibrinolytic phase of disseminated intravascular coagulopathy. Results of the conventional haemostasis tests supported those obtained on thromboelastography. Humane euthanasia was performed because of poor prognosis and progressive disease, making further follow-up unavailable. As demonstrated in this case report, thromboelastography was found to be a helpful diagnostic tool for the diagnosis and monitoring of the hyperfibrinolytic phases of disseminated intravascular coagulopathy.

Topics: Animals; Blood Coagulation; Disseminated Intravascular Coagulation; Dog Diseases; Dogs; Fatal Outcome; Hemangiosarcoma; Male; Thrombelastography; Thrombin; Thromboplastin

Topics: Adult; Biomarkers; Cell Adhesion Molecules; Endothelium, Vascular; Factor VIII; Hemangiosarcoma; Humans; Intercellular Adhesion Molecule-1; Liver Neoplasms; Male; Thromboplastin; Tumor Cells, Cultured

Vascular endothelial cells are a target for blood-borne pathogens which may affect their integrity and thromboresistant properties. Here, we report that cultured bovine and human endothelial cells lose their thromboresistance following interaction with the avian hemangioma-inducing retrovirus. We show that the envelope (env) gene product, glycoprotein 85, is responsible for this effect, which appears soon after infection without viral replication or cell transformation. Induction of thrombogenicity is associated with a reduction in prostacyclin release and increased expression of tissue factor. These observations may explain the occurrence of thrombosis frequently observed in association with the hemangiosarcomas induced by avian hemangioma-inducing retrovirus. These unique endothelial cell-virus interactions may also be a model for the pathogenesis of various vascular diseases.

Topics: Animals; Avian Leukosis Virus; Cattle; Cells, Cultured; Endothelium, Vascular; Epoprostenol; Extracellular Matrix; Hemangiosarcoma; Kinetics; Platelet Aggregation; Thromboplastin; Thrombosis; Viral Envelope Proteins