Lu Yangyang, Li Yan, Sun Xueying, Li Xin, Zhao Shufen, Fang Yuanyuan, Qiu Wensheng, Luo Cheng, Qi Weiwei
Department of Oncology, The Affiliated Hospital of Qingdao University, Qingdao, China.
School of Basic Medical Sciences, Yichun University, Yichun, China.
Free Radic Biol Med. 2026 Feb 16;244:284-295. doi: 10.1016/j.freeradbiomed.2025.12.019. Epub 2025 Dec 15.
Gastric cancer treatment remains challenging due to tumor heterogeneity and drug resistance. Cuproptosis, a novel form of cell death induced by excessive copper accumulation in mitochondria, is regulated by FDX1 and involves cytotoxic aggregation of lipoylated proteins such as DLAT. Given the markedly elevated copper levels observed in gastric cancer tissues, triggering cuproptosis represents a promising therapeutic strategy. Since cuproptosis strongly relies on active mitochondrial respiration, we hypothesized that mitochondrial uncoupling-which dissociates electron transport from oxidative phosphorylation by dissipating the proton gradient across the inner mitochondrial membrane, thereby enhancing respiratory activity-could sensitize gastric cancer cells to cuproptosis. In this study, we first established a cuproptosis model in gastric cancer cells using elesclomol combined with copper. We then systematically evaluated the enhancing effect of mitochondrial uncoupling on this process. Using the classical uncoupler FCCP and clinically relevant agents (niclosamide, nitazoxanide, and oxyclozanide), we confirmed mitochondrial uncoupling through membrane potential depolarization, an increased NAD/NADH ratio, elevated oxygen consumption, and decreased ATP levels. Importantly, mitochondrial uncoupling significantly potentiated the cytotoxic effect of elesclomol-copper ion treatment in gastric cancer cells, which was closely associated with increased DLAT oligomerization. Mechanistic investigations revealed that mitochondrial uncoupling promotes cuproptosis susceptibility by upregulating DLAT and FDX1 protein expression and remodeling cellular metabolism. In summary, this study highlights the key role of mitochondrial uncoupling in amplifying cuproptosis and proposes a novel combination strategy based on metabolic intervention. These findings offer a new theoretical foundation and potential clinical translation prospects for gastric cancer treatment.
由于肿瘤异质性和耐药性，胃癌治疗仍然具有挑战性。铜死亡是一种由线粒体中过量铜积累诱导的新型细胞死亡形式，由FDX1调节，涉及硫辛酰化蛋白（如DLAT）的细胞毒性聚集。鉴于在胃癌组织中观察到铜水平显著升高，触发铜死亡代表了一种有前景的治疗策略。由于铜死亡强烈依赖于活跃的线粒体呼吸，我们假设线粒体解偶联——通过消散线粒体内膜上的质子梯度使电子传递与氧化磷酸化分离，从而增强呼吸活性——可以使胃癌细胞对铜死亡敏感。在本研究中，我们首先使用依沙莫林联合铜在胃癌细胞中建立了铜死亡模型。然后，我们系统地评估了线粒体解偶联对这一过程的增强作用。使用经典解偶联剂FCCP和临床相关药物（氯硝柳胺、硝唑尼特和奥昔氯生），我们通过膜电位去极化、NAD/NADH比值增加、耗氧量升高和ATP水平降低证实了线粒体解偶联。重要的是，线粒体解偶联显著增强了依沙莫林-铜离子处理对胃癌细胞的细胞毒性作用，这与DLAT寡聚化增加密切相关。机制研究表明，线粒体解偶联通过上调DLAT和FDX1蛋白表达以及重塑细胞代谢来促进铜死亡易感性。总之，本研究强调了线粒体解偶联在放大铜死亡中的关键作用，并提出了一种基于代谢干预的新型联合策略。这些发现为胃癌治疗提供了新的理论基础和潜在的临床转化前景。
