PTK2 and breast cancer: For example, LGMN derived from breast cancer cells binds to Integrin αvβ3 on the cell surface through the RGD (Arginyl-glycyl-aspartic acid) motif, activating the FAK (Focal Adhesion Kinase)/Src (Steroid receptor coactivator)/RhoA (Ras homolog gene family member A) signaling pathway and promoting cancer cell migration and invasion independent of LGMN protease activity [10].