PECAM1 and neoplasm: We also stained OVCAR5 tumor sections for CD31 and found a significantly lower mean (± SEM) number of vessels in mice given the combination of L-Grb2 and paclitaxel (17.78 ± 3.46, p < 0.01 compared to control) than in the L-Grb2–only (24.88 ± 3.88), control (33.33 ± 3.25), and paclitaxel-only (34.11 ± 4.75) groups (Figure 5D).