PECAM1 and cancer: Analyzing samples from predisposing conditions (such as ulcerative colitis) to neoplastic pre-cancerous lesions to invasive cancer, we detected a significant increase in angiogenesis using CD31 staining, inflammatory cells expressing CD68 or CD15, cytokines like IL-6 and other mediators that play a key role in the innate immune system, in particular TLR4.