CXCR4 and neoplasm: Importantly, CCL2 can also bind to CCR2–CXCR4 heterodimers.[63] CXCR4 was also reduced in PYK2 KO macrophages (Figure 6F,H, J), and is known to play a role in cell migration, suggesting that PYK2 regulates TAM recruitment through both cell autonomous‐dependent mechanisms and tumor–macrophage communication.