Background: Patients diagnosed with gallbladder carcinoma (GBC) accompanied by hepatic metastasis exhibit unfavorable prognoses generally. Mitochondrial dysfunction promotes cellular transformation and cancer cell survival implicating its importance in cancer development. Previous studies have indicated that dynamin 1 like (DNM1L) is a key mediator of mitochondrial fission. However, whether DNM1L regulates mitochondrial homeostasis in GBC remains unknown.

Methods: The morphological changes of mitochondria were investigated by transmission electron microscopy and mitoTracker red staining. Co-immunoprecipitation assay was performed to detect the interaction of ubiquitin-specific protease-3 (USP3) and DNM1L. The cell-derived xenograft and liver metastasis tumor models were established to validate the function of DNM1L in vivo. The metabolomics data from transcriptomics/metabolomics were analyzed to identify the differentially expressed genes/metabolites of DNM1L in GBC.

Results: DNM1L exhibited a marked upregulation in clinical GBC tissues compared to the adjacent tissues, and it promoted proliferation, invasiveness, and migration capability of GBC cells by inducing mitochondrial dysfunction. Mice subcutaneously injected with DNM1L overexpression cells exhibited elevated intrahepatic metastatic nodules within their livers. USP3, a deubiquitinating enzyme, was demonstrated to directly interact with DNM1L and it specifically cleaved the K48-linked polyubiquitin chains to deubiquitinate and stabilize DNM1L. By integrating two omics, we found several altered pathways and speculated that DNM1L disturbed DNA synthesis and glycine, serine, threonine, and pyrimidine metabolism pathways.

Conclusion: Our findings suggest that DNM1L is a promising clinical target for GBC treatment and that focusing on DNM1L may provide new insights into GBC strategy.

Keywords: DNM1L; Deubiquitination; Gallbladder cancer; Mitochondrial homeostasis; USP3.

© 2025. The Author(s).

背景: 胆囊癌（GBC）伴有肝转移的患者通常预后不佳。线粒体功能障碍促进细胞转化和癌细胞存活，暗示其在线粒体疾病发展中的重要性。先前的研究表明，动力相关蛋白 1 样（DNM1L）是线粒体分裂的关键介导物。然而，DNM1L 是否调节 GBC 中的线粒体稳态尚不清楚。

方法: 通过透射电子显微镜和 mitoTracker red 染色研究了线粒体形态变化，并进行了 Co-免疫沉淀测定以检测泛素特异性蛋白酶 3（USP3）与 DNM1L 的相互作用。建立了细胞来源的异种移植和肝转移肿瘤模型，以在体内验证 DNM1L 的功能。从转录组学/代谢组学数据中分析了 DNM1L 在 GBC 中差异表达的基因/代谢物。

结果: 与邻近组织相比，临床 GBC 组织中的 DNM1L 显示出显著上调，并通过诱导线粒体功能障碍促进 GBC 细胞的增殖、侵袭和迁移能力。皮下注射过表达 DNM1L 的细胞的小鼠表现出肝脏内肝转移结节增多。USP3，一种去泛素化酶，被证明直接与 DNM1L 相互作用，并且它特异性地切割 K48 链接的多聚泛素链以去泛素化和稳定 DNM1L。通过整合两种组学数据，我们发现了若干改变的通路，并推测 DNM1L 扰乱了 DNA 合成以及甘氨酸、丝氨酸、苏氨酸和嘧啶代谢途径。

结论: 我们的研究结果表明，DNM1L 是 GBC 治疗的一个有希望的临床靶点，并且关注 DNM1L 可能为 GBC 策略提供新的见解。

关键词: DNM1L；去泛素化；胆囊癌；线粒体稳态；USP3.

© 2025. The Author(s).