Research Paper Volume 12, Issue 6 pp 5091—5120

Time-dependent interactions of blood platelets and cancer cells, accompanied by extramedullary hematopoiesis, lead to increased platelet activation and reactivity in a mouse orthotopic model of breast cancer – implications for pulmonary and liver metastasis

Figure 12. Time-course of the formation of platelet-cancer cell aggregates during 5-week tumor progression in the mouse model of breast cancer. Results are presented as median (horizontal line) and interquartile range (box) (n = 8). The expressions of CD24 (A) or CD44 (B) within the population of the CD41/61-gated cells (platelets) were measured using flow cytometry in non-fixed ‘washed blood’ withdrawn immediately (t0) or after 2 (t2), 3 (t3), 4 (t4) or 5 weeks (t5) from the injection of 4T1 cells. Results are expressed as the percent fraction of CD24/CD41/61 or CD44/CD41/61-positive cells. More experimental details are given in the Materials and methods section. Statistical significance of differences, estimated with Kruskal-Wallis test followed by post hoc Conover-Inman all-pairwise comparisons or one-way ANOVA followed by Tukey’s multiple comparisons test, was: CD24/CD41/61-positive cells (4T1-platelet aggregates), P1,α < 0.001, 4T1 t5 > 4T1 t0; P1,α < 0.01, 4T1 t5 > 4T1 t3, 4T1 t5 > 4T1 t2; P1,α < 0.05, 4T1 t5 > 4T1 t4, 4T1 t4 > 4T1 t0; CD44/CD41/61-positive cells (4T1-platelet aggregates), P1,α < 0.01, 4T1 t5 > 4T1 t4 > 4T1 t3 > 4T1 t0; P1,α < 0.01, 4T1 t5 > 4T1 t4 > 4T1 t2 > 4T1 t0.