Inhibition of tumor growth was observed when PYK2 was ablated either in the BC cells (Figure 2B; Figure S2A, Supporting Information), in the TME (Figure 2G), or selectively in macrophages of the TME (Figure 5E), demonstrating the striking influence of TAMs on tumor growth, and the critical role of PYK2 in macrophage–breast cancer communication. Here, PTK2B is linked to breast carcinoma.