Nitric Oxide Services, LLC, St. John Paul II Center for Science Innovation, North Canton, OH, U.S.A.
Department of Math & Sciences, Walsh University, North Canton, OH, U.S.A.
Anticancer Res. 2020 Dec;40(12):6751-6763. doi: 10.21873/anticanres.14698. Epub 2020 Dec 7.
BACKGROUND/AIM: Chemoresistance is a major consequence of multicycle chemotherapy and can be attributed to constitutive activation of pro-survival signaling pathways. Nitric oxide is a ubiquitous signaling molecule which has been shown to inhibit several pathways involved with survival signaling in cancer cells. We have previously demonstrated the anti-tumor activity of a nitric oxide-donor, nitrosylcobalamin (NO-Cbl), mediated by increased expression of tumor necrosis factor-related apoptosis-inducing ligand (Apo2L/TRAIL) and its receptors in human tumors. We also demonstrated that a functional Apo2L/TRAIL receptor is necessary for the induction of cell death by NO-Cbl and the Apo2L/TRAIL death receptor DR4 (TRAIL R1) is S-nitrosylated. The aim of the study was to examine the effects of nitric oxide (NO) on nuclear factor kappa B (NF-κB) and determine whether nitric oxide could sensitize drug-resistant melanomas to Apo2L/TRAIL via inhibition of NF-κB or inhibitor kappa B kinase (IKK).
Antiproliferative effects of NO-Cbl and Apo2L/TRAIL were assessed in malignant melanomas and non-tumorigenic melanocyte and fibroblast cell lines. Athymic nude mice bearing human melanoma A375 xenografts were treated with NO-Cbl and Apo2L/TRAIL. Apoptosis was measured by the TUNEL assay. The activation status of NF-κB was established by assaying luciferase reporter activity, the phosphorylation status of IκBα, and in vitro IKK activity.
NO-Cbl sensitized Apo2L/TRAIL-resistant melanoma cell lines to growth inhibition by Apo2L/TRAIL, but had minimal effect on normal cell lines. NO-Cbl and Apo2L/TRAIL exerted synergistic anti-tumor activity against A375 xenografts. NO-Cbl suppressed Apo2L/TRAIL- and TNF-α-mediated activation of a transfected NF-κB-driven luciferase reporter. NO-Cbl inhibited IKK activation, characterized by decreased phosphorylation of IκBα.
NO-Cbl treatment rendered Apo2L/TRAIL-resistant malignancies sensitive to the anti-tumor effects of Apo2L/TRAIL in vitro and in vivo. The use of nitric oxide to inhibit NF-κB and potentiate the effects of chemotherapeutic agents, such as Apo2L/TRAIL, represents a promising anti-cancer combination based on recent clinical investigations of anti-TRAIL antibodies for cancer treatment strategies.
背景/目的：多周期化疗导致的化疗耐药是一个主要后果，其可归因于存活信号通路的组成型激活。一氧化氮是一种普遍存在的信号分子，已被证明可抑制癌细胞中几种与存活信号相关的通路。我们之前已经证明，一氧化氮供体硝普酸钠（NO-Cbl）通过增加人肿瘤中肿瘤坏死因子相关凋亡诱导配体（Apo2L/TRAIL）及其受体的表达来发挥抗肿瘤活性。我们还证明，NO-Cbl 和 Apo2L/TRAIL 死亡受体 DR4（TRAIL R1）的功能性 Apo2L/TRAIL 受体的表达对于诱导细胞死亡是必需的，并且 Apo2L/TRAIL 死亡受体 DR4（TRAIL R1）被 S-亚硝基化。本研究的目的是研究一氧化氮（NO）对核因子 kappa B（NF-κB）的影响，并确定一氧化氮是否可以通过抑制 NF-κB 或抑制κB 激酶（IKK）使耐药性黑色素瘤对 Apo2L/TRAIL 敏感。
在恶性黑色素瘤和非致瘤性黑色素细胞和成纤维细胞系中评估了 NO-Cbl 和 Apo2L/TRAIL 的抗增殖作用。用 NO-Cbl 和 Apo2L/TRAIL 治疗携带人黑色素瘤 A375 异种移植物的裸鼠。通过 TUNEL 测定法测量细胞凋亡。通过测定荧光素酶报告基因活性、IκBα的磷酸化状态和体外 IKK 活性来确定 NF-κB 的激活状态。
NO-Cbl 使 Apo2L/TRAIL 耐药的黑色素瘤细胞系对 Apo2L/TRAIL 的生长抑制作用敏感，但对正常细胞系的作用很小。NO-Cbl 和 Apo2L/TRAIL 对 A375 异种移植物具有协同的抗肿瘤活性。NO-Cbl 抑制 Apo2L/TRAIL 和 TNF-α介导的转染的 NF-κB 驱动的荧光素酶报告基因的激活。NO-Cbl 抑制 IKK 激活，表现为 IκBα的磷酸化减少。
NO-Cbl 处理使 Apo2L/TRAIL 耐药的恶性肿瘤对 Apo2L/TRAIL 的体外和体内抗肿瘤作用敏感。基于最近对用于癌症治疗策略的抗 TRAIL 抗体的临床研究，使用一氧化氮抑制 NF-κB 并增强化疗药物（如 Apo2L/TRAIL）的作用代表了一种很有前途的抗癌联合治疗方法。
