College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, Scotland, UK.
Siriraj Centre of Research Excellence for Cancer Immunotherapy, Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok, Thailand.
Sci Rep. 2024 Apr 18;14(1):8998. doi: 10.1038/s41598-024-59451-3.
Pancreatic ductal adenocarcinoma (PDAC) is considered the third leading cause of cancer mortality in the western world, offering advanced stage patients with few viable treatment options. Consequently, there remains an urgent unmet need to develop novel therapeutic strategies that can effectively inhibit pro-oncogenic molecular targets underpinning PDACs pathogenesis and progression. One such target is c-RAF, a downstream effector of RAS that is considered essential for the oncogenic growth and survival of mutant RAS-driven cancers (including KRAS PDAC). Herein, we demonstrate how a novel cell-penetrating peptide disruptor (DRx-170) of the c-RAF-PDE8A protein-protein interaction (PPI) represents a differentiated approach to exploiting the c-RAF-cAMP/PKA signaling axes and treating KRAS-c-RAF dependent PDAC. Through disrupting the c-RAF-PDE8A protein complex, DRx-170 promotes the inactivation of c-RAF through an allosteric mechanism, dependent upon inactivating PKA phosphorylation. DRx-170 inhibits cell proliferation, adhesion and migration of a KRAS PDAC cell line (PANC1), independent of ERK1/2 activity. Moreover, combining DRx-170 with afatinib significantly enhances PANC1 growth inhibition in both 2D and 3D cellular models. DRx-170 sensitivity appears to correlate with c-RAF dependency. This proof-of-concept study supports the development of DRx-170 as a novel and differentiated strategy for targeting c-RAF activity in KRAS-c-RAF dependent PDAC.
胰腺导管腺癌 (PDAC) 被认为是西方世界癌症死亡的第三大主要原因,为晚期患者提供了几种可行的治疗选择。因此,迫切需要开发新的治疗策略,以有效抑制 PDAC 发病机制和进展所依赖的致癌分子靶点。其中一个靶点是 c-RAF,它是 RAS 的下游效应物,被认为是突变 RAS 驱动的癌症(包括 KRAS PDAC)致癌生长和存活所必需的。在此,我们展示了一种新型的穿透细胞肽破坏剂 (DRx-170) 如何破坏 c-RAF-PDE8A 蛋白-蛋白相互作用 (PPI),从而代表了一种有区别的方法来利用 c-RAF-cAMP/PKA 信号轴并治疗 KRAS-c-RAF 依赖性 PDAC。通过破坏 c-RAF-PDE8A 蛋白复合物,DRx-170 通过依赖于失活 PKA 磷酸化的变构机制促进 c-RAF 的失活。DRx-170 抑制 KRAS PDAC 细胞系 (PANC1) 的细胞增殖、粘附和迁移,而不依赖于 ERK1/2 活性。此外,DRx-170 与 afatinib 联合使用可显著增强 2D 和 3D 细胞模型中 PANC1 的生长抑制作用。DRx-170 的敏感性似乎与 c-RAF 的依赖性相关。这项概念验证研究支持将 DRx-170 开发为一种新型的、有区别的策略,用于靶向 KRAS-c-RAF 依赖性 PDAC 中的 c-RAF 活性。