PECAM1 and prostate neoplasm: However, an increase in cell apoptosis as demonstrated by a significant increase in cleaved caspase-3 staining was detected in prostate tumors from mice injected with shCdGAP cells (Fig. 8f) whereas no difference in the cell proliferation marker Ki-67 or CD-31 staining was detected between control and shCdGAP tumors (Supplementary Fig. 4a, b).