PECAM1 and neoplasm: In line with these results, intratumoral injection of cGAMP on B16 tumor-bearing IFN-β–YFP reporter mice significantly induced IFN-β–GFP signal in endothelial cells (CD45–CD31+), as well as that in macrophages (CD45+F4/80+) and DCs (CD45+CD11c+) with even higher levels (Figure 3, F and G).