Department of Clinical and Biological Sciences, University of Turin, Regione Gonzole 10, 10043, Orbassano, Italy.
Department of Molecular Biotechnology and Health Sciences, University of Turin, Via Nizza 52, 10126, Turin, Italy.
J Exp Clin Cancer Res. 2021 Apr 16;40(1):136. doi: 10.1186/s13046-021-01921-x.
Oxidative stress is a hallmark of many cancers. The increment in reactive oxygen species (ROS), resulting from an increased mitochondrial respiration, is the major cause of oxidative stress. Cell fate is known to be intricately linked to the amount of ROS produced. The direct generation of ROS is also one of the mechanisms exploited by common anticancer therapies, such as chemotherapy.
We assessed the role of NFKBIA with various approaches, including in silico analyses, RNA-silencing and xenotransplantation. Western blot analyses, immunohistochemistry and RT-qPCR were used to detect the expression of specific proteins and genes. Immunoprecipitation and pull-down experiments were used to evaluate protein-protein interactions.
Here, by using an in silico approach, following the identification of NFKBIA (the gene encoding IκBα) amplification in various cancers, we described an inverse correlation between IκBα, oxidative metabolism, and ROS production in lung cancer. Furthermore, we showed that novel IκBα targeting compounds combined with cisplatin treatment promote an increase in ROS beyond the tolerated threshold, thus causing death by oxytosis.
NFKBIA amplification and IκBα overexpression identify a unique cancer subtype associated with specific expression profile and metabolic signatures. Through p65-NFKB regulation, IκBα overexpression favors metabolic rewiring of cancer cells and distinct susceptibility to cisplatin. Lastly, we have developed a novel approach to disrupt IκBα/p65 interaction, restoring p65-mediated apoptotic responses to cisplatin due to mitochondria deregulation and ROS-production.
氧化应激是许多癌症的标志。活性氧（ROS）的增加，源于线粒体呼吸的增加，是氧化应激的主要原因。细胞命运与产生的 ROS 量密切相关。ROS 的直接产生也是常见抗癌疗法（如化疗）所利用的机制之一。
我们通过各种方法评估了 NFKBIA 的作用，包括计算机分析、RNA 沉默和异种移植。使用 Western blot 分析、免疫组织化学和 RT-qPCR 来检测特定蛋白质和基因的表达。免疫沉淀和下拉实验用于评估蛋白质-蛋白质相互作用。
在这里，我们通过计算机分析方法，在确定各种癌症中 NFKBIA（编码 IκBα 的基因）扩增后，描述了肺癌中 IκBα、氧化代谢和 ROS 产生之间的反比关系。此外，我们表明，新型 IκBα 靶向化合物与顺铂治疗联合使用会导致 ROS 超过耐受阈值增加，从而导致氧化细胞死亡。
NFKBIA 扩增和 IκBα 过表达鉴定了一种独特的癌症亚型，与特定的表达谱和代谢特征相关。通过 p65-NFKB 调节，IκBα 过表达有利于癌细胞的代谢重编程，并对顺铂具有不同的敏感性。最后，我们开发了一种破坏 IκBα/p65 相互作用的新方法，由于线粒体失调和 ROS 产生，恢复了 p65 介导的对顺铂的凋亡反应。
