To do this, we treated wild-type or Kindlin-2 knockdown breast cancer cell BT549 with EGF for 5 min to activate EGF-induced protein tyrosine phosphorylation and then applied the Src superbinder (engineered Src kinase SH2 domain) photo-pTyr-scaffold to capture Kindlin-2 regulated pTyr protein complexes in response to EGF stimulation by mass spectrometry (MS). Here, EGF is linked to breast carcinoma.