[摘 要] 目的：探究泛素特异性蛋白酶20（USP20）在胰腺癌组织中的表达及其对胰腺癌细胞增殖和迁移的作用及分子机制。 方法：用癌症基因组图谱（TCGA）数据库数据分析USP20和扭曲家族碱性螺旋-环-螺旋转录因子（TWIST）在胰腺癌组织中的表 达，通过 Kaplan-Meier 曲线评估其与患者预后的相关性。常规培养正常胰腺细胞 HPNE 和胰腺癌细胞 MIAPaca2、BxPC3、 PANC1、SW1990 和 Aspc1，用 WB 法检测 USP20 蛋白在其中的表达。将 PANC1 和 SW1990 细胞分为 shNC 组、shUSP20-1 组和 shUSP20-2组，用转染试剂将相应的慢病毒感染各组细胞，用qPCR法和WB法验证敲减效率，用CCK-8法、克隆形成实验、划痕 愈合实验、Transwell实验和流式细胞术分别检测各组细胞的增殖、迁移能力和细胞周期，WB法检测各组细胞中的上皮-间质转化 转录因子相关蛋白的表达。免疫共沉淀和泛素化实验检测USP20是否与TWIST相互作用，阐明USP20是否通过泛素化途径调 控TWIST表达。结果：USP20、TWIST mRNA在胰腺癌组织中均呈高表达（均P < 0.05），其表达水平与患者预后呈负相关（均 P < 0.05）。USP20蛋白在PANC1 、SW1990、MIAPaca2和BxPC3细胞中均呈高表达（均P < 0.001）。敲减USP20均可明显抑制 PANC1 和 SW1990 细胞的增殖、迁移能力（均 P < 0.001）。USP20 与 TWIST 相互结合（P < 0.05 或 P < 0.01），USP20 通过降低 TWIST泛素化水平稳定其表达（P < 0.01）。结论：USP20在胰腺癌组织中呈高表达，通过去泛素化TWIST稳定其表达，从而促进 胰腺癌细胞的增殖和迁移，提示USP20可能成为胰腺癌诊断和治疗的潜在靶点。

[Abstract] Objective: To investigate the expression of ubiquitin-specific protease 20 (USP20) in pancreatic cancer tissues and its role and molecular mechanism in the proliferation and migration of pancreatic cancer cells. Methods: The Cancer Genome Atlas (TCGA) database was used to analyze USP20 and TWIST family bHLH transcription factor (TWIST) expression in pancreatic cancer tissues. Kaplan-Meier curve analysis was used evaluate their correlation with patient prognosis. Normal pancreatic cells (HPNE) and pancreatic cancer cells (MIAPaca2, BxPC3, PANC1, SW1990, Aspc1) were routinely cultured, and USP20 protein expression was detected by Western blot (WB). PANC1 and SW1990 cells were divided into shNC, shUSP20-1, and shUSP20-2 groups, and transfected with corresponding lentiviruses. Knockdown efficiency was verified by qPCR and WB. Cell proliferation, migration, and cell cycle distribution were assessed using CCK-8, colony formation, wound healing, Transwell assays, and flow cytometry, respectively. WB was used to detect the expression of epithelial-mesenchymal transition (EMT)-related transcription factors. Co-immunoprecipitation (CoIP) and ubiquitination assays were conducted to determine whether USP20 interacts with TWIST and regulates its expression via the ubiquitination pathway. Results: USP20 and TWIST mRNA levels were significantly upregulated in pancreatic cancer tissues (both P < 0.05), and their levels were negatively correlated with patient prognosis (both P < 0.05). USP20 protein was highly expressed in PANC1, SW1990, MIAPaca2, and BxPC3 cells (all P < 0.001). Knockdown of USP20 significantly inhibited the proliferation and migration of PANC1 and SW1990 cells (all P < 0.001). USP20 interacted with TWIST (P < 0.05 or P < 0.01) and stabilized TWIST expression by reducing its ubiquitination level (P < 0.01). Conclusion: USP20 is highly expressed in pancreatic cancer tissues and promotes pancreatic cancer cell proliferation and migration by stabilizing TWIST through deubiquitination. These findings suggest that USP20 may serve as a potential diagnostic and therapeutic target in the treatment of pancreatic cancer.

[基金项目] 国家自然科学基金（No. U2004138）；江苏省高等学校自然科学研究项目（No. 21KJD310002）；江苏省青蓝工程 优秀教学团队（No. 2022-25）