Interactions of tumor cells with platelets and leukocytes activate HMVECs. (A) Human lung microvascular endothelial cells (HMVECs) were cocultured with LS180 or Colo205 cells in the absence or presence of polymorphonuclear leukocytes (PMNs), monocytes, and platelets. Representative flow cytometric data of E-selectin expression on HMVECs are shown. CD105 was used to identify HMVECs. (B) Statistical analysis of multiple coculture experiments (n = 4-6) measuring E-selectin expression on HMVECs. Percentage of E-selectin–positive HMVECs is presented (mean ± SEM). Statistical significance was determined by Bonferroni multiple comparison test. **P < .01; ***P < .001. (C) Representative fluorescence images of p65 localization in HMVECs. Nuclear localization of p65 was determined by colocalization (white) of p65 (red) with DAPI (4,6 diamidino-2-phenylindole [Sigma]; blue. HMVECs were detected by CD31 antibody (green). (D) Relative nuclear localization of p65 in HMVECs determined by Imaris software. Data are presented as mean ± SEM of 3 independent experiments.