Department of Laboratory Medicine, School of Medicine, Hunan Normal University, Changsha 410013, China.
School of Medicine, Chongqing University, Chongqing 400030, China.
Cells. 2024 Oct 30;13(21):1798. doi: 10.3390/cells13211798.
Ubiquitination is an important post-transcriptional modification crucial for maintaining cell homeostasis. As a deubiquitination enzyme, ubiquitin-specific protease 1 (USP1) is associated with tumor progression; however, its role in bladder cancer is unknown. This study aimed to analyze USP1 expression and study its roles in bladder cancer.
The web server GEPIA was used to analyze the USP1 expression. To explore USP1's function in bladder cancer, we constructed USP1-knockout cell lines in UMUC3 cells. A FLAG-USP1 (WT USP1) plasmid and a plasmid FLAG-USP1 C90S (catalytic-inactive mutant) were used to overexpress USP1 in T24 cells. CCK8, colony formation, and Transwell assays were used to assess cell viability, proliferation, and migration. RNA-sequencing (RNA-seq) and dual-luciferase reporter assays were performed to screen the pathway. Co-immunoprecipitation and immunofluorescence were used to explore the interaction between USP1 and c-MYC. A xenograft mouse model was used to study the role of USP1 in bladder cancer.
USP1 expression was upregulated in human bladder cancer cells and correlated with poor patient prognosis. USP1 overexpression promoted cell proliferation, clone formation, and migration, and this was attenuated by genetic ablation of USP1. Furthermore, we observed that deficiency inhibited tumor formation in vivo. Mechanistically, the c-MYC pathway was remarkably activated compared with the other pathways. Furthermore, USP1 could interact with c-MYC and increase c-MYC's stability depending on the catalytic activity of USP1.
Our results suggested that high expression of USP1 promotes bladder cancer progression by stabilizing c-MYC; hence, USP1 may serve as a novel therapeutic target for treating bladder cancer.
泛素化是一种重要的转录后修饰，对于维持细胞内稳态至关重要。作为一种去泛素化酶，泛素特异性蛋白酶 1（USP1）与肿瘤进展有关；然而，其在膀胱癌中的作用尚不清楚。本研究旨在分析 USP1 的表达，并研究其在膀胱癌中的作用。
使用 web 服务器 GEPIA 分析 USP1 的表达。为了探讨 USP1 在膀胱癌中的功能，我们在 UMUC3 细胞中构建了 USP1 敲除细胞系。使用 FLAG-USP1（WT USP1）质粒和质粒 FLAG-USP1 C90S（催化失活突变体）在 T24 细胞中过表达 USP1。使用 CCK8、集落形成和 Transwell 测定评估细胞活力、增殖和迁移。进行 RNA 测序（RNA-seq）和双荧光素酶报告基因测定筛选通路。使用 co-immunoprecipitation 和免疫荧光来探索 USP1 和 c-MYC 之间的相互作用。使用异种移植小鼠模型研究 USP1 在膀胱癌中的作用。
USP1 在人膀胱癌细胞中表达上调，并与患者预后不良相关。USP1 的过表达促进了细胞增殖、克隆形成和迁移，而 USP1 的遗传缺失则减弱了这一作用。此外，我们观察到缺陷抑制了体内肿瘤的形成。机制上，与其他通路相比，c-MYC 通路显著被激活。此外，USP1 可以与 c-MYC 相互作用，并依赖于 USP1 的催化活性增加 c-MYC 的稳定性。
我们的结果表明，高表达的 USP1 通过稳定 c-MYC 促进膀胱癌的进展；因此，USP1 可能成为治疗膀胱癌的一种新的治疗靶点。
