Figure 5. Effect of BxPc-3 tumors on thrombosis in mice.

(A–E) BxPc-3 cells or PBS were injected into the pancreas of nude mice. Tumors were allowed to develop for 8–16 weeks until tumors reached a maximum of 2 cm³ in size. Blood was drawn from the inferior vena cava (IVC) and plasma collected and stored at −80°C. Levels of (A) microvesicles (MV) tissue factor activity (TF), (B) thrombin-antithrombin complexes (TATc) and (C) platelet factor 4 (PF4) were measured in mouse plasma from tumor-bearing mice and controls. (*P<0.05, PBS n=10, BxPc-3 n=5). Data were analyzed by unpaired student’s t-test. Tumor weights (g) with detectable MV TF activity are indicated in panel A. Mice with tumor weights of 1.9 g and 0.3 g did not have detectable MV TF activity. (D) Thrombosis was induced in BxPc-3 tumor-bearing nude mice or PBS controls by stenosis of the IVC. Thrombus formation was quantified in mice using high-frequency ultrasonography. Data is presented as mean ± SEM. (p<0.001. PBS n=6, BxPc-3 n=5). Data were analyzed by two-way ANOVA with Bonferroni posttests comparing all data to the PBS control at each time point. (E) Percent incidence of thrombosis is shown from the thrombosis experiments in panel D. There was no difference in thrombus incidence found by log-rank sums test between tumor bearing and non-tumor bearing mice.