USP9X and cholangiocarcinoma: In summary, this study is the first to demonstrate that USP9X exerts tumor-suppressive effects in cholangiocarcinoma by deubiquitinating and stabilizing the EGLN3 protein, thereby activating the KIF1Bβ-mediated apoptotic pathway and establishing a novel USP9X-EGLN3-KIF1Bβ tumor-suppressive axis (Figure 6).