Barbosa Mélanie A G, Kruschel Ryan D, Almeida Maria João, Pereira Rúben F, Xavier Cristina P R, McCarthy Florence O, Vasconcelos M Helena
i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135, Porto, Portugal; Cancer Drug Resistance Group, IPATIMUP - Institute of Molecular Pathology and Immunology, University of Porto, 4200-135, Porto, Portugal; FFUP - Faculty of Pharmacy of the University of Porto, 4050-313, Porto, Portugal.
School of Chemistry, Analytical and Biological Chemistry Research Facility, University College Cork, Cork, T12 K8AF, Ireland.
Eur J Pharmacol. 2025 Feb 5;988:177234. doi: 10.1016/j.ejphar.2024.177234. Epub 2024 Dec 24.
Multidrug resistance (MDR) is a major challenge in cancer research. Collateral sensitizers, compounds that exploit the enhanced defense mechanisms of MDR cells as weaknesses, are a proposed strategy to overcome MDR. Our previous work reported the synthesis of two novel Isoquinolinequinone (IQQ) N-oxides that induce collateral sensitivity in MDR ABCB1-overexpressing non-small cell lung cancer (NSCLC) and colorectal cancer cells. Herein, we aimed to investigate underlying mechanisms of antitumor and collateral sensitivity activity of these compounds. We evaluated their effect on cancer cell viability, proliferation, cell cycle profile, and studied their cytotoxicity in non-tumorigenic cells. Their antitumor effect was further studied using NSCLC and colorectal cancer MDR spheroids. To understand underlying collateral sensitivity mechanisms, we assessed the effect on rhodamine-123 accumulation, ROS production, GSH/GSSG balance and expression of key proteins associated with metabolism and redox balance. Both compounds reduced the viability of MDR cells, as 2D cultures or as spheroids, without decreasing the growth of a human nontumorigenic cell line, and increased rhodamine-123 accumulation in MDR NCI-H460/R cells. Moreover, RK2 increased ROS, disrupted GSH balance, and altered expression of proteins associated with oxidative stress protection, particularly in NCI-H460/R cells. The collateral sensitivity effect of RK3 could not be attributed to redox balance disruption, but increased IDH1 expression following treatment suggests a potential metabolic shift in MDR cells. These findings highlight RK2 and RK3 as promising candidates for next stages of drug development. Their distinct mechanisms of action could lead to therapeutic solutions for MDR-related cancers, specifically linked to ABCB1 overexpression.
多药耐药性（MDR）是癌症研究中的一项重大挑战。旁侧敏化剂是一类利用MDR细胞增强的防御机制中的弱点的化合物，是克服MDR的一种提议策略。我们之前的工作报道了两种新型异喹啉醌（IQQ）N-氧化物的合成，它们可在过表达MDR ABCB1的非小细胞肺癌（NSCLC）和结肠癌细胞中诱导旁侧敏感性。在此，我们旨在研究这些化合物抗肿瘤和旁侧敏感性活性的潜在机制。我们评估了它们对癌细胞活力、增殖、细胞周期分布的影响，并研究了它们在非致瘤性细胞中的细胞毒性。使用NSCLC和结肠直肠癌MDR球体进一步研究了它们的抗肿瘤作用。为了了解潜在的旁侧敏感性机制，我们评估了它们对罗丹明-123积累、活性氧（ROS）产生、谷胱甘肽/氧化型谷胱甘肽（GSH/GSSG）平衡以及与代谢和氧化还原平衡相关的关键蛋白表达的影响。这两种化合物都降低了MDR细胞（无论是二维培养还是球体形式）的活力，而不降低人非致瘤性细胞系的生长，并增加了MDR NCI-H460/R细胞中罗丹明-123的积累。此外，RK2增加了ROS，破坏了GSH平衡，并改变了与氧化应激保护相关的蛋白表达，特别是在NCI-H460/R细胞中。RK3的旁侧敏感性作用不能归因于氧化还原平衡的破坏，但处理后异柠檬酸脱氢酶1（IDH1）表达增加表明MDR细胞中可能存在代谢转变。这些发现突出了RK2和RK3作为药物开发下一阶段有前景的候选物。它们独特的作用机制可能为与MDR相关的癌症，特别是与ABCB1过表达相关的癌症带来治疗解决方案。
