PO.ET06.01 · 实验与分子治疗
氧化应激介导的非凋亡、非自噬性细胞死亡:一种在机制上独特的克服结直肠癌细胞耐药策略
Oxidative stress-mediated non-apoptotic, non-autophagic cell death: A mechanistically distinct strategy to overcome resistance in colorectal cancer cells
作者与单位 Authors & Affiliations
摘要 Abstract
中文摘要
癌症仍是全球主要的死亡原因之一,其治疗失败往往由凋亡耐药所驱动,这是限制传统抗癌治疗疗效的一大障碍。靶向替代性的、不依赖caspase的细胞死亡通路已成为克服这种耐药的有前景策略。本研究中,我们评估了两种机制上截然不同的小分子——一种BCL-XL抑制剂和一种NRF2激活剂——对结直肠癌细胞系的影响,以探究它们诱导非凋亡细胞死亡的能力。两种药物均以剂量和时间依赖的方式降低细胞活力。NRF2激活剂在较低浓度下即触发细胞质空泡化,这是副凋亡(paraptosis)的特征,并伴随内质网(ER)扩张、氧化应激以及副凋亡的关键抑制因子Alix的下调。这种细胞死亡方式需要新生蛋白质合成,且不依赖caspase激活、PARP切割和DNA片段化。相反,BCL-XL抑制剂表现出在空泡化诱导的细胞死亡与经典凋亡之间的剂量依赖性转换,后者以磷脂酰丝氨酸外翻和DNA片段化为标志。这些发现强调了氧化应激介导的、与空泡化相关的非凋亡细胞死亡是一种机制上独特且具有治疗意义的模式,可用于靶向凋亡耐药的癌细胞。这一方法可能为利用肿瘤氧化还原脆弱性、同时绕过传统细胞死亡通路的创新癌症疗法铺平道路。
查看英文原文 English abstract
Cancer remains a leading cause of mortality worldwide, with therapeutic failure often driven by apoptosis resistance a major hurdle that limits the efficacy of conventional anticancer therapies. Targeting alternative, caspase-independent cell death pathways has emerged as a promising strategy to overcome this resistance. In this study, we evaluated the effects of two mechanistically distinct small molecules a BCL-XL inhibitor and an NRF2 activator on colorectal cancer cell lines to investigate their ability to induce non-apoptotic cell death. Both agents reduced cell viability in a dose- and time-dependent manner. The NRF2 activator triggered cytoplasmic vacuolation at lower concentrations, characteristic of paraptosis, accompanied by endoplasmic reticulum (ER) dilation, oxidative stress, and downregulation of Alix, a key inhibitor of paraptosis. This mode of cell death required de novo protein synthesis and was independent of caspase activation, PARP cleavage, and DNA fragmentation. In contrast, the BCL-XL inhibitor displayed a dose-dependent switch between vacuolation-induced cell death and classical apoptosis, marked by phosphatidylserine externalization and DNA fragmentation. These findings underscore oxidative stress-mediated, vacuolation-associated non-apoptotic cell death as a mechanistically distinct and therapeutically relevant modality for targeting apoptosis-resistant cancer cells. This approach may pave the way for innovative cancer therapies that exploit tumor redox vulnerabilities while bypassing traditional cell death pathways.
利益披露 Disclosure
M. Rehman, None..
A. Gajani, None..
M. Fatima, None..
P. Jawaid, None..
A. Shafiq, None..
A. H. Rajabali, None.