Fig. 3

Effect of F11R/JAM-A-derived peptide (P4D) on colony formation by endothelial and breast cancer cells. The colonies were counted 14 days after cell incubation with the peptides and were expressed as the surviving factor (SF), that is the number of colonies that arise after treatment of cells. SF was calculated as described in Materials and Methods section. The cells were untreated (Ctrl), treated with the control scrambled peptide (Scr) or with the F11R/JAM-A antagonistic peptide (P4D) at a concentration of 500 μM. Shapiro–Wilk normality W test was performed whether the data fall upon Gaussian distribution: EA.hy926–passed (P-values for Ctrl: 0.9591, for Scr: 0.1546, for P4D: 0.7538); HMEC-1–passed (P-values for Ctrl: 0.5587, for Scr: 0.6681, for P4D: 0.1515); MDA-MB-231–passed (P-values for Ctrl: 0.2779, for Scr: 0.4005, for P4D: 0.5815). Subsequently, the statistical analysis was performed by one-way ANOVA followed, where applicable, by Tukey’s multiple comparison test. The differences between the groups where found to be not significantly different for EA.hy926 (P = 0.1863) and for HMEC-1 (P = 0.1774). The differences between the MDA-MB-231 groups were significant (P < 0.0001) and the results of Tukey’s multiple comparisons test were as follows: for Ctrl vs. Scr P = 0.3410; for Ctrl vs. P4D P < 0.0001; for Scr vs. P4D P = 0.0015