PECAM1 and neoplasm: Immunohistologic endpoints were analyzed on formalin-fixed paraffin-embedded 4-μm tissue sections derived from tumor xenografts and tumor lesions in the lung derived from the orthotopic model and stained with hematoxylin and eosin (Abcam, ab245880) and anti-CD31–directed antibody (1:10, Dako; M0823, RRID: AB_2114471).