CRIPTO and cancer: In the context of PCa bone metastasis, CRIPTO was shown to modulate TGF-β signaling, which is one of the key molecules of bone remodeling following metastatic progression and it was previously demonstrated that CRIPTO binds TGF-β and inhibits its signaling, potentially supporting an inhibition of the cytostatic effect of TGF-β in cancer [18,151,175].