thromboplastin and Neoplasms--Germ-Cell-and-Embryonal

Patients with germ cell tumors (GCTs) receiving cisplatin-based chemotherapy are at increased risk of thrombosis, but the underlying cellular and molecular mechanisms remain obscure.. To study baseline tissue factor (TF) expression by GCT cell lines and its modulation by cisplatin treatment.. TF expression was assessed by single-stage clotting and thrombin generation assay, flow cytometry, ELISA, and Western blot analysis. Cell cycle analysis and detection of phosphatidylserine (PS) membrane exposure were carried out by flow cytometry. TF mRNA was analyzed by quantitative RT-PCR.. Significant expression of TF-specific procoagulant activity (PCA) was detected on three non-seminoma (NT2, 2102Ep, NCCIT) and one seminoma cell line (TCam-2). Treatment with 0.4μM cisplatin (corresponding to the IC50) for 48hrs increased TF PCA on NT2 cells 3-fold, an effect that was largely independent of PS exposure and that could not be explained by translocation of active TF from intracellular storage pools. Cisplatin-induced TF PCA expression in NT2 cells did not occur before 12hrs, but was steady thereafter and accompanied by a 2-fold increase in total and surface-located TF antigen. Importantly, increased TF gene transcription or production and release of an intermediate factor were not involved in this process. Cell cycle analysis suggested that cisplatin-induced G2/M arrest resulted in an accumulation of procoagulant TF on the membrane surface of NT2 cells.. In addition to induction of apoptosis/necrosis with PS-mediated activation of preformed TF, cisplatin may alter the procoagulant phenotype of GCT cells through an increase in total cellular TF antigen.

Topics: Antineoplastic Agents; Apoptosis; Cell Line, Tumor; Cell Survival; Cisplatin; Dose-Response Relationship, Drug; Gene Expression Regulation, Neoplastic; HL-60 Cells; Humans; Neoplasms, Germ Cell and Embryonal; Thromboplastin

Brain tumor patients have an increased risk of venous thromboembolism (VTE). An important role in cancer-related VTE has been suggested for tissue factor (TF), the main initiator of the coagulation cascade. We conducted a prospective cohort study to determine whether expression levels of TF in brain tumors are associated with future VTE.. We immunohistochemically determined TF-expression in brain tumor specimens of 96 adult patients (8 low-grade and 82 high-grade gliomas, 6 embryonal tumors) that were included in the Vienna Cancer and Thrombosis Study (CATS). Each patient was prospectively followed until the occurrence of VTE and/or death within a period of two years or loss of follow-up.. Fifteen brain tumor patients (15.6%) developed VTE during follow-up. Seventy-seven brain tumors (80.2%) stained positive for TF. Staining was strong in 13 (13.5%), moderate in 64 (66.7%) and negative in 19 (19.8%) tumors. No statistically significant association between TF-expression (negative, focal, widespread) and the occurrence of VTE was found. The hazard ratio (HR) for VTE was 1.30 (95% confidence interval [CI]: 054 - 3.14, p=0.567) when patients with negative-, focal- and widespread TF expression were compared and not statistically significant. Also when tumors were categorized into two groups (focal/widespread versus negative TF-expression), the HR for future VTE was not statistically significant (HR: 1.45, 95% CI: 0.44 - 7.37; p=0.578). An association can still not be definitely excluded, as this study was underpowered.. Our data indicate that TF-expression levels in brain tumors are not strongly associated with future VTE.

Topics: Brain Neoplasms; Female; Glioma; Humans; Immunohistochemistry; Male; Middle Aged; Neoplasms, Germ Cell and Embryonal; Risk Factors; Thromboplastin; Venous Thromboembolism