Kennedy Barry E, Giacomantonio Michael, Murphy J Patrick, Cutler Samuel, Sadek Maryanne, Konda Prathyusha, Paulo Joao A, Pathak Gopal P, Renkens Saskia H J, Grieve Stacy, Pol Jonathan, Gygi Steven P, Richardson Christopher, Gaston Daniel, Reiman Anthony, Kroemer Guido, Elnenaei Manal O, Gujar Shashi A
Department of Pathology, Dalhousie University, Rm. 11J Sir Charles Tupper Medical Building, 5850 College Street, Halifax, NS B3H 1X5, Canada.
Department of Biology, University of Prince Edward Island, Charlottetown, PEI C1A 4P3, Canada.
Mol Ther Oncolytics. 2022 Feb 20;24:695-706. doi: 10.1016/j.omto.2022.02.017. eCollection 2022 Mar 17.
Cancer cell energy metabolism plays an important role in dictating the efficacy of oncolysis by oncolytic viruses. To understand the role of multiple myeloma metabolism in reovirus oncolysis, we performed semi-targeted mass spectrometry-based metabolomics on 12 multiple myeloma cell lines and revealed a negative correlation between NAD+ levels and susceptibility to oncolysis. Likewise, a negative correlation was observed between the activity of the rate-limiting NAD+ synthesis enzyme NAMPT and oncolysis. Indeed, depletion of NAD+ levels by pharmacological inhibition of NAMPT using FK866 sensitized several myeloma cell lines to reovirus-induced killing. The myelomas that were most sensitive to this combination therapy expressed a functional p53 and had a metabolic and transcriptomic profile favoring mitochondrial metabolism over glycolysis, with the highest synergistic effect in KMS12 cells. Mechanistically, U-C-labeled glucose flux, extracellular flux analysis, multiplex proteomics, and cell death assays revealed that the reovirus + FK866 combination caused mitochondrial dysfunction and energy depletion, leading to enhanced autophagic cell death in KMS12 cells. Finally, the combination of reovirus and NAD+ depletion achieved greater antitumor effects in KMS12 tumors and patient-derived CD138+ multiple myeloma cells. These findings identify NAD+ depletion as a potential combinatorial strategy to enhance the efficacy of oncolytic virus-based therapies in multiple myeloma.
癌细胞能量代谢在决定溶瘤病毒的溶瘤疗效中起着重要作用。为了解多发性骨髓瘤代谢在呼肠孤病毒溶瘤中的作用，我们对12种多发性骨髓瘤细胞系进行了基于半靶向质谱的代谢组学研究，发现NAD⁺水平与溶瘤敏感性之间呈负相关。同样，限速NAD⁺合成酶NAMPT的活性与溶瘤之间也观察到负相关。事实上，使用FK866通过药理学抑制NAMPT来降低NAD⁺水平，使几种骨髓瘤细胞系对呼肠孤病毒诱导的杀伤敏感。对这种联合疗法最敏感的骨髓瘤表达功能性p53，其代谢和转录组谱有利于线粒体代谢而非糖酵解，在KMS12细胞中具有最高的协同效应。从机制上讲，U-C标记的葡萄糖通量、细胞外通量分析、多重蛋白质组学和细胞死亡分析表明，呼肠孤病毒+FK866组合导致线粒体功能障碍和能量消耗，导致KMS12细胞中自噬性细胞死亡增强。最后，呼肠孤病毒和NAD⁺消耗的组合在KMS12肿瘤和患者来源的CD138⁺多发性骨髓瘤细胞中实现了更大的抗肿瘤效果。这些发现确定NAD⁺消耗是一种潜在的联合策略，可增强基于溶瘤病毒的疗法在多发性骨髓瘤中的疗效。
