Department of Medical Biochemistry and Cell Biology, Institute of Biomedicine, University of Gothenburg, Sweden.
Cima, University of Navarra, Pio XII, Pamplona, Spain.
Cancer Res. 2021 Mar 15;81(6):1457-1471. doi: 10.1158/0008-5472.CAN-19-3499. Epub 2020 Dec 28.
Neuroblastoma has a low mutation rate for the gene. Alternative ways of p53 inactivation have been proposed in neuroblastoma, such as abnormal cytoplasmic accumulation of wild-type p53. However, mechanisms leading to p53 inactivation via cytoplasmic accumulation are not well investigated. Here we show that the neuroblastoma risk-associated locus 6p22.3-derived tumor suppressor is a p53-responsive lncRNA that regulates p53 subcellular levels. Low expression of provided resistance to genotoxic drugs by promoting p53 accumulation in cytoplasm and loss from mitochondrial and nuclear compartments. Depletion of altered CRM1 function and contributed to the loss of p53-dependent nuclear gene expression during genotoxic drug treatment. CRM1 inhibition rescued p53-dependent nuclear functions and sensitized -depleted cells to genotoxic drugs. Combined inhibition of CRM1 and MDM2 was even more effective in sensitizing aggressive neuroblastoma cells with p53 cytoplasmic accumulation. Thus, our mechanistic studies uncover an -dependent CRM1/MDM2-based potential combination therapy for patients with high-risk neuroblastoma. SIGNIFICANCE: This study shows how a p53-responsive lncRNA mediates chemotherapeutic response by modulating nuclear p53 pathways and identifies a potential treatment strategy for patients with high-risk neuroblastoma.
神经母细胞瘤的 基因突变速率较低。已经提出了神经母细胞瘤中 p53 失活的其他途径,例如野生型 p53 的异常细胞质积累。然而,导致通过细胞质积累使 p53 失活的机制尚未得到很好的研究。在这里,我们表明神经母细胞瘤风险相关基因座 6p22.3 衍生的肿瘤抑制因子 是一种 p53 反应性 lncRNA,可调节 p53 亚细胞水平。 的低表达通过促进细胞质中 p53 的积累并从线粒体和核区室丢失来提供对遗传毒性药物的抗性。 耗竭改变了 CRM1 功能,并有助于在遗传毒性药物处理期间丧失 p53 依赖性核基因表达。CRM1 抑制挽救了 p53 依赖性核功能,并使耗尽细胞对遗传毒性药物敏感。CRM1 和 MDM2 的联合抑制甚至更有效地使具有 p53 细胞质积累的侵袭性神经母细胞瘤细胞敏感。因此,我们的机制研究揭示了一种基于依赖于 的 CRM1/MDM2 的潜在联合治疗方法,可用于治疗高危神经母细胞瘤患者。
本研究表明,p53 反应性 lncRNA 通过调节核 p53 途径来介导化疗反应,并为高危神经母细胞瘤患者确定了一种潜在的治疗策略。