PTK2 and breast cancer: For instance, the P21 (RAC1) activated kinase 1 (PAK1)-dependent phosphorylation of a splicing isoform of the SRC-3 oncogene/c-Src signaling adaptor molecule, namely SRC-3Δ4, colocalized with FAK and EGFR at the plasma membrane, thereby enhancing the migration of breast cancer cells upon EGF stimulation [102].