Department of Molecular and Cellular Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas.
Department of Biochemistry and Molecular Biology, UTHealth Medical School, Houston, Texas.
Cancer Res. 2021 Aug 1;81(15):4054-4065. doi: 10.1158/0008-5472.CAN-20-3792. Epub 2021 Jun 11.
Pancreatic ductal adenocarcinoma (PDAC) is almost universally lethal. A critical unmet need exists to explore essential susceptibilities in PDAC and to identify druggable targets to improve PDAC treatment. KRAS mutations dominate the genetic landscape of PDAC and lead to activation of multiple downstream pathways and cellular processes. Here, we investigated the requirement of these pathways for tumor maintenance using an inducible -driven PDAC mouse model (iKras model), identifying that RAF-MEK-MAPK signaling is the major effector for oncogenic KRAS-mediated tumor maintenance. However, consistent with previous studies, MEK inhibition had minimal therapeutic effect as a single agent for PDAC and . Although MEK inhibition partially downregulated transcription of glycolysis genes, it failed to suppress glycolytic flux in PDAC cells, which is a major metabolic effector of oncogenic KRAS. Accordingly, an genetic screen identified multiple glycolysis genes as potential targets that may sensitize tumor cells to MEK inhibition. Inhibition of glucose metabolism with low-dose 2-deoxyglucose in combination with a MEK inhibitor induced apoptosis in -driven PDAC cells . The combination also inhibited xenograft PDAC tumor growth and prolonged overall survival in a genetically engineered PDAC mouse model. Molecular and metabolic analyses indicated that co-targeting glycolysis and MAPK signaling results in apoptosis via induction of lethal endoplasmic reticulum stress. Together, our work suggests that combined inhibition of glycolysis and the MAPK pathway may serve as an effective approach to target KRAS-driven PDAC. SIGNIFICANCE: This study demonstrates the critical role of glucose metabolism in resistance to MAPK inhibition in KRAS-driven pancreatic cancer, uncovering a potential therapeutic approach for treating this aggressive disease.
胰腺导管腺癌 (PDAC) 几乎普遍致命。目前迫切需要探索 PDAC 的基本易感性,并确定可用药的靶点,以改善 PDAC 的治疗效果。KRAS 突变主导 PDAC 的遗传景观,并导致多个下游途径和细胞过程的激活。在这里,我们使用诱导型驱动的 PDAC 小鼠模型 (iKras 模型) 研究了这些途径对肿瘤维持的需求,确定 RAF-MEK-MAPK 信号传导是致癌 KRAS 介导的肿瘤维持的主要效应物。然而,与先前的研究一致,MEK 抑制作为 PDAC 的单一药物治疗效果极小,并且。尽管 MEK 抑制部分下调了糖酵解基因的转录,但它未能抑制 PDAC 细胞中的糖酵解通量,这是致癌 KRAS 的主要代谢效应物。因此,遗传筛选确定了多个糖酵解基因作为潜在的靶点,这些靶点可能使肿瘤细胞对 MEK 抑制敏感。低剂量 2-脱氧葡萄糖与 MEK 抑制剂联合抑制葡萄糖代谢可诱导驱动的 PDAC 细胞凋亡。该组合还抑制了异种移植 PDAC 肿瘤的生长,并延长了遗传工程 PDAC 小鼠模型中的总生存期。分子和代谢分析表明,靶向糖酵解和 MAPK 信号的共同抑制通过诱导致命的内质网应激导致细胞凋亡。总之,我们的工作表明,联合抑制糖酵解和 MAPK 通路可能是针对 KRAS 驱动的 PDAC 的有效方法。意义:这项研究表明葡萄糖代谢在抵抗 MAPK 抑制在 KRAS 驱动的胰腺癌中的关键作用,揭示了治疗这种侵袭性疾病的潜在治疗方法。