CCL2 and neoplasm: In a mouse tumor model of pancreatic adenocarcinoma (PDAC), local delivery of a single 20 Gy dose markedly augmented the release of CCL2 by tumor cells, which was consequently accompanied by the infiltration of inflammatory macrophages expressing C-C chemokine receptor type 2 (CCR2, the cognate receptor for CCL2) (Figure 1) (41).