CCL2 and neoplasm: CCL2 has been reported to play a critical role in macrophage recruitment and residence.[39] We assessed the impact of Ccn1 deletion in KPC cells on macrophage recruitment by placing tumor cells in the Transwell chamber and immune cells above, with a layer of Matrigel on top (Figure5A), which demonstrated that Ccn1‐deficient KPC cells induced greater macrophages migration (Figure 5B).