PTK2B and breast cancer: The primary tumor was also tested through IHC, NP‐C8018‐7840 significantly inhibited the phosphorylation of PTK2B at Tyr402, PTK at Tyr397, and SRC at Tyr416 of the breast cancer primary site, but had little impact on total‐PTK2B, total‐PTK, and total‐SRC (Figure S13B, Supporting Information).