PECAM1 and neoplasm: We then analyzed tumor tissues using immunohistochemistry (IHC) and found that treatment with AP-4-139B led to reduced immunostaining for Ki67 (proliferation) and CD31 (angiogenesis), along with an increase in staining for cell death markers Cleaved Lamin A and Cleaved Caspase 3 (Fig. 5J, K, Supplementary Fig. 5D, E).