PECAM1 and colorectal carcinoma: In addition, we assessed the the microvessel density in transplanted CRC tumors by CD31 immuno-reactivity and hemoglobin concentration and found that the TFS treatment group decreased intra-tumoral microvessel density and hemoglobin concentration in comparison to the PBS control group (p < 0.05) suggesting the anti-angiogeneic effect of TFS (Figure 7D).