Zhang Junjing, Tian Tongguan, Li Xinxing, Xu Kai, Lu Yao, Li Xia, Zhao Xinyu, Cui Ziyi, Wang Zhenxiang, Zhou Yuefan, Xu Yixin, Li Hongchen, Zhang Yan, Du Yu, Lv Lei, Xu Yanping
Department of Gastrointestinal Surgery, Tongji Hospital, Shanghai Key Laboratory of Signaling and Disease Research, Frontier Science Center for Stem Cell Research, School of Life Sciences and Technology, Tongji University, Shanghai, China.
International & Talent Office, Tongji Hospital, Tongji University, Shanghai, China.
Clin Transl Med. 2025 Mar;15(3):e70271. doi: 10.1002/ctm2.70271.
Gastric cancer is one of the most prevalent malignant tumors within the digestive system, and ferroptosis playing a crucial role in its progression. Glutathione peroxidase 4 (GPX4), a key negative regulator of ferroptosis, is highly expressed in gastric cancer and contributes to tumor growth. Targeting the regulation of GPX4 has emerged as a promising approach to induce ferroptosis and develop effective therapy for gastric cancer.
To confirm that OTUD5 is a deubiquitinase of GPX4 and regulates ferroptosis, we performed Western blotting, Co-IP, immunofluorescence, quantitative real-time PCR, Ub assay and flow cytometry experiments. To explore the physiological function of OUTD5, we knocked out the Otud5 gene in the mouse gastric cancer cell line (MFC) using CRISPR-Cas9 and eatablished the subcutaneous tumour model. Immunohistochemistry (IHC) analysis was used to inveatigate the pathological correlation in human gastric cancer.
We report that ovarian tumor domain-containing 5 (OTUD5) interacts with, deubiquitylates and stabilizes GPX4. OTUD5 depletion destabilizes GPX4, promotes lipid peroxidation and sensitizes gastric cancer cells to ferroptosis. Moreover, the p53 activator nutlin-3a suppresses OTUD5 transcription, leading to GPX4 degradation and ferroptosis of gastric cancer cells. Notably, only wild-type p53 has the capacity to inhibit OTUD5 transcription, while p53 mutations or deficiencies correlate with increased OTUD5 expression, promoting gastric cancer progression. Additionally, OTUD5 silencing and nutlin-3a-induced GPX4 degradation enhances the sensitivity of gastric cancer cells to ferroptosis in vivo. Subsequently, the p53/OTUD5/GPX4 axis is confirmed in clinical gastric cancer samples.
Collectively, these findings elucidate a mechanism whereby p53 inactivation upregulates OTUD5 transcription to deubiquitylate and stablize GPX4, resulting in ferroptosis inhibition and gastric cancer progression. This discovery highlights the potential therapeutic value of targeting OTUD5 to promote ferroptosis in p53-inactivated gastric cancer.
OTUD5 mediates GPX4 deubiquitination to regulate its stability. Deletion of OTUD5 promotes ferroptosis and inhibits tumor growth. Wild type p53 inhibits OTUD5 transcription, thereby promoting GPX4 degradation and inhibiting the development of gastric cancer. OTUD5, GPX4 expression and p53 activity are highly correlated and correlates with clinical progression in STAD.
胃癌是消化系统中最常见的恶性肿瘤之一，铁死亡在其进展中起关键作用。谷胱甘肽过氧化物酶4（GPX4）是铁死亡的关键负调节因子，在胃癌中高表达并促进肿瘤生长。靶向调节GPX4已成为诱导铁死亡并开发有效胃癌治疗方法的一种有前景的途径。
为了证实OTUD5是GPX4的去泛素化酶并调节铁死亡，我们进行了蛋白质免疫印迹、免疫共沉淀、免疫荧光、定量实时聚合酶链反应、泛素检测和流式细胞术实验。为了探究OUTD5的生理功能，我们使用CRISPR-Cas9在小鼠胃癌细胞系（MFC）中敲除Otud5基因并建立皮下肿瘤模型。免疫组织化学（IHC）分析用于研究人胃癌中的病理相关性。
我们报道含卵巢肿瘤结构域5（OTUD5）与GPX4相互作用、使其去泛素化并使其稳定。OTUD5缺失使GPX4不稳定，促进脂质过氧化并使胃癌细胞对铁死亡敏感。此外，p53激活剂nutlin-3a抑制OTUD5转录，导致GPX4降解和胃癌细胞铁死亡。值得注意的是，只有野生型p53有能力抑制OTUD5转录，而p53突变或缺陷与OTUD5表达增加相关，促进胃癌进展。此外，OTUD5沉默和nutlin-3a诱导的GPX4降解增强了胃癌细胞在体内对铁死亡的敏感性。随后，在临床胃癌样本中证实了p53/OTUD5/GPX4轴。
总的来说，这些发现阐明了一种机制，即p53失活上调OTUD5转录以去泛素化并稳定GPX4，导致铁死亡抑制和胃癌进展。这一发现突出了靶向OTUD5以促进p53失活型胃癌中铁死亡的潜在治疗价值。
OTUD5介导GPX4去泛素化以调节其稳定性。缺失OTUD5促进铁死亡并抑制肿瘤生长。野生型p53抑制OTUD5转录，从而促进GPX4降解并抑制胃癌发展。OTUD5、GPX4表达和p53活性高度相关，并与胃腺癌的临床进展相关。
