PTBP3 and neoplasm: PTBP3 binds with the caveolin 1 (CAV1) CU-rich region to regulate ASEs, activating steroid receptor coactivator (Src) and focal adhesion kinase (FAK) proteins to promote GC lymphatic metastasis.275 In addition, HNRNPM binds with circURI1 (unconventional prefoldin RPB5 interactor 1) in GC to inhibit tumor metastasis, which may serve as a self-protection mechanism.