Singh Anand, Pruett Nathanael, Pahwa Roma, Mahajan Arushi P, Schrump David S, Hoang Chuong D
Thoracic Surgery Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA.
Urology Oncology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA.
Mol Ther Nucleic Acids. 2021 Apr 3;24:669-681. doi: 10.1016/j.omtn.2021.04.001. eCollection 2021 Jun 4.
Malignant pleural mesothelioma (MPM) is an incurable surface neoplasm with peculiar pathobiology. MPM proliferates by using the tyrosine-kinase-Ras pathway. Despite representing an attractive therapeutic target, there are no standard agent(s) specifically inhibiting Ras signaling adopted in clinical settings. We posited that biologic effects of microRNA (miRNA) can disrupt this molecular network. Using patient samples, cell lines, and murine tumor xenograft models, we confirmed specific genes in the Ras pathway are targeted by an MPM-associated miRNA and then examined its therapeutic effects. We verified significant and consistent downregulation of miR-206 in MPM tissues. When miR-206 is ectopically re-expressed in MPM cells and delivered to tumor xenografts in mice, it exerted significant cell killing by suppressing multiple components of the receptor-tyrosine-kinase-Ras-cell-cycle-signaling network; some of which were prognostic when overexpressed and/or have not been druggable. Of note, we validated as a novel target of miR-206. Overall, this miR-206-targeting mechanism manifested as induced G1/S cell cycle arrest. In addition, we identified a novel MPM therapeutic combination by adding systemic-route abemaciclib with local-route miR-206, which showed additive efficacy translating to improved survival. Our pre-clinical study suggests a potential pathophysiologic role for, and therapeutic relevance of, miR-206 in MPM.
恶性胸膜间皮瘤(MPM)是一种具有独特病理生物学特性的无法治愈的体表肿瘤。MPM通过酪氨酸激酶-Ras途径增殖。尽管Ras信号通路是一个有吸引力的治疗靶点,但临床上尚无专门抑制Ras信号传导的标准药物。我们推测微小RNA(miRNA)的生物学效应可以破坏这一分子网络。利用患者样本、细胞系和小鼠肿瘤异种移植模型,我们证实了Ras途径中的特定基因是一种与MPM相关的miRNA的作用靶点,然后研究了其治疗效果。我们验证了MPM组织中miR-206存在显著且一致的下调。当miR-206在MPM细胞中异位重新表达并递送至小鼠体内的肿瘤异种移植模型时,它通过抑制受体酪氨酸激酶-Ras-细胞周期信号网络的多个组分发挥显著的细胞杀伤作用;其中一些组分在过表达时具有预后意义且/或尚未有可靶向的药物。值得注意的是,我们验证了[具体内容缺失]是miR-206的一个新靶点。总体而言,这种靶向miR-206的机制表现为诱导G1/S期细胞周期阻滞。此外,我们通过将全身给药的阿贝西利与局部给药的miR-206联合使用,确定了一种新的MPM治疗组合,该组合显示出相加疗效并转化为生存期的改善。我们的临床前研究表明miR-206在MPM中具有潜在的病理生理作用和治疗相关性。