Nrf2调控的分子机制以及这些机制如何影响用于疾病干预的化学调节。
Molecular mechanisms of Nrf2 regulation and how these influence chemical modulation for disease intervention.
作者信息
Harder Bryan, Jiang Tao, Wu Tongde, Tao Shasha, Rojo de la Vega Montserrat, Tian Wang, Chapman Eli, Zhang Donna D
机构信息
Department of Pharmacology and Toxicology, University of Arizona, Tucson, Arizona 85721, U.S.A.
Department of Pharmacology and Toxicology, University of Arizona, Tucson, Arizona 85721, U.S.A. Arizona Cancer Center, University of Arizona, Tucson, Arizona 85724, U.S.A.
出版信息
Biochem Soc Trans. 2015 Aug;43(4):680-6. doi: 10.1042/BST20150020. Epub 2015 Aug 3.
Nrf2 (nuclear factor erytheroid-derived-2-like 2) transcriptional programmes are activated by a variety of cellular stress conditions to maintain cellular homoeostasis. Under non-stress conditions, Nrf2 is under tight regulation by the ubiquitin proteasome system (UPS). Detailed mechanistic investigations have shown the Kelch-like ECH-associated protein 1 (Keap1)-cullin3 (Cul3)-ring-box1 (Rbx1) E3-ligase to be the primary Nrf2 regulatory system. Recently, both beta-transducin repeat-containing E3 ubiquitin protein ligase (β-TrCP) and E3 ubiquitin-protein ligase synoviolin (Hrd1) have been identified as novel E3 ubiquitin ligases that negatively regulate Nrf2 through Keap1-independent mechanisms. In addition to UPS-mediated regulation of Nrf2, investigations have revealed a cross-talk between Nrf2 and the autophagic pathway resulting in activation of Nrf2 in a non-canonical manner. In addition to regulation at the protein level, Nrf2 was recently shown to be regulated at the transcriptional level by oncogenic K-rat sarcoma (Ras). A consequence of these differential regulatory mechanisms is the dual role of Nrf2 in cancer: the canonical, protective role and the non-canonical 'dark-side' of Nrf2. Based on the protective role of Nrf2, a vast effort has been dedicated towards identifying novel chemical inducers of Nrf2 for the purpose of chemoprevention. On the other hand, upon malignant transformation, some cancer cells have a constitutively high level of Nrf2 offering a growth advantage, as well as rendering cancer cells resistant to chemotherapeutics. This discovery has led to a new paradigm in cancer treatment; the initially counterintuitive use of Nrf2 inhibitors as adjuvants in chemotherapy. Herein, we will discuss the mechanisms of Nrf2 regulation and how this detailed molecular understanding can be leveraged to develop Nrf2 modulators to prevent diseases, mitigate disease progression or overcome chemoresistance.
核因子红细胞衍生 2 样 2(Nrf2)转录程序可被多种细胞应激条件激活,以维持细胞内稳态。在非应激条件下,Nrf2 受到泛素蛋白酶体系统(UPS)的严格调控。详细的机制研究表明, Kelch 样 ECH 相关蛋白 1(Keap1)-cullin3(Cul3)-环框蛋白 1(Rbx1)E3 连接酶是主要的 Nrf2 调节系统。最近,含β-转导蛋白重复序列的 E3 泛素蛋白连接酶(β-TrCP)和 E3 泛素蛋白连接酶滑膜素(Hrd1)均被鉴定为新型 E3 泛素连接酶,它们通过不依赖 Keap1 的机制对 Nrf2 进行负调控。除了 UPS 介导的对 Nrf2 的调控外,研究还揭示了 Nrf2 与自噬途径之间的相互作用,导致 Nrf2 以非经典方式被激活。除了在蛋白质水平上的调控外,最近还发现 Nrf2 在转录水平上受到致癌性 K-鼠肉瘤(Ras)的调控。这些不同调控机制的一个结果是 Nrf2 在癌症中的双重作用:经典的保护作用和 Nrf2 的非经典“阴暗面”。基于 Nrf2 的保护作用,人们致力于寻找新型 Nrf2 化学诱导剂以用于化学预防。另一方面,在恶性转化后,一些癌细胞具有持续高水平的 Nrf2,这不仅为癌细胞提供了生长优势,还使癌细胞对化疗药物产生抗性。这一发现导致了癌症治疗的新范式;最初看似违反直觉地将 Nrf2 抑制剂用作化疗佐剂。在此,我们将讨论 Nrf2 的调控机制,以及如何利用这种详细的分子理解来开发 Nrf2 调节剂,以预防疾病、减轻疾病进展或克服化疗耐药性。