Department of Biology, Georgia State University, Atlanta, GA, USA-30303.
Caris Life Sciences, Tempe, Arizona, USA-85282.
Theranostics. 2021 Aug 27;11(18):9089-9106. doi: 10.7150/thno.62724. eCollection 2021.
: Cancer cells rely on glucose metabolism for fulfilling their high energy demands. We previously reported that monoethanolamine (Etn), an orally deliverable lipid formulation, reduced intracellular glucose and glutamine levels in prostate cancer (PCa). Glucose deprivation upon Etn treatment exacerbated metabolic stress in PCa, thereby enhancing cell death. Moreover, Etn was potent in inhibiting tumor growth in a PCa xenograft model. However, the precise mechanisms underlying Etn-induced metabolic stress in PCa remain elusive. The purpose of the present study was to elucidate the mechanisms contributing to Etn-mediated metabolic rewiring in PCa. : Glucose transporters (GLUTs) facilitate glucose transport across the plasma membrane. Thus, we assessed the expression of GLUTs and the internalization of GLUT1 in PCa. We also evaluated the effects of Etn on membrane dynamics, mitochondrial structure and function, lipid droplet density, autophagy, and apoptosis in PCa cells. : Compared to other GLUTs, GLUT1 was highly upregulated in PCa. We observed enhanced GLUT1 internalization, altered membrane dynamics, and perturbed mitochondrial structure and function upon Etn treatment. Etn-induced bioenergetic stress enhanced lipolysis, decreased lipid droplet density, promoted accumulation of autophagosomes, and increased apoptosis. : We provide the first evidence that Etn alters GLUT1 trafficking leading to metabolic stress in PCa. By upregulating phosphatidylethanolamine (PE), Etn modulates membrane fluidity and affects mitochondrial structure and function. Etn also induces autophagy in PCa cells, thereby promoting apoptosis. These data strongly suggest that Etn rewires cellular bioenergetics and could serve as a promising anticancer agent for PCa.
: 癌细胞依赖葡萄糖代谢来满足其高能量需求。我们之前报道过,单乙醇胺(Etn),一种可口服的脂质制剂,可降低前列腺癌(PCa)细胞内的葡萄糖和谷氨酰胺水平。Etn 处理导致葡萄糖剥夺会加剧 PCa 中的代谢应激,从而增强细胞死亡。此外,Etn 在 PCa 异种移植模型中抑制肿瘤生长的效果显著。然而,Etn 诱导的 PCa 代谢应激的确切机制仍不清楚。本研究旨在阐明 Etn 介导的 PCa 代谢重编程的机制。: 葡萄糖转运蛋白(GLUTs)促进葡萄糖穿过质膜的转运。因此,我们评估了 GLUTs 的表达和 GLUT1 在 PCa 中的内化。我们还评估了 Etn 对 PCa 细胞的膜动力学、线粒体结构和功能、脂滴密度、自噬和细胞凋亡的影响。: 与其他 GLUTs 相比,GLUT1 在 PCa 中高度上调。我们观察到 Etn 处理后 GLUT1 内化增强、膜动力学改变以及线粒体结构和功能受损。Etn 诱导的生物能应激增强了脂肪分解、降低了脂滴密度、促进了自噬体的积累并增加了细胞凋亡。: 我们首次提供证据表明,Etn 改变 GLUT1 转运导致 PCa 中的代谢应激。通过上调磷脂酰乙醇胺(PE),Etn 调节膜流动性并影响线粒体结构和功能。Etn 还诱导 PCa 细胞中的自噬,从而促进细胞凋亡。这些数据强烈表明,Etn 重新构建了细胞的生物能量学,可作为治疗 PCa 的有前途的抗癌剂。