Abstract 6160: Tie2-mediated AMPK activation by ferritin-based protein C nanoparticles inhibits advanced prostate cancer development through induction of vasodilation

Abstract

Abstract Prostate cancer (PCa) is one of the most common malignancies and the second-leading cause of cancer-related mortality in men in Western countries. Androgen deprivation therapy (ADT) is an initial systemic therapy for advanced PCa, but almost all cancer eventually becomes castration resistant. Recently, we introduced ferritin-based protein C nanoparticles (PCNs), known as TFG and TFMG, which enhance normalization of the tumor vasculature. However, the exact underlying mechanism how PCNs induces AMP-activated protein kinase (AMPK) activation and anti-tumor activity in castration-resistant prostate cancer (CRPC) remains unknown. Here, we investigated the role of PCNs for CRPC development in endothelial cells. We found that TFMG inhibits prostate cancer castration resistance by activating AMPK through the Tie2-mediated signaling pathway. TFMG treatment increased AMPK phosphorylation at Thr172 and acetyl-CoA carboxylase (ACC) at Ser79 in EA.hy926 cells. TFMG treatment also significantly increased the phosphorylation of endothelial nitric oxide synthase (eNOS) with inducing nitric oxide (NO) production in EA.hy926 cells. In addition, TFMG treatment induced the vasodilatory effect in isolated rat mesenteric resistance arteries (MRAs), which was blocked by NO synthase inhibitor L-NAME. Interestingly, these effects were all abolished by pretreatment with Compound C (an AMPK inhibitor), rebastinib (selective Tie2 Inhibitor), AMPK knockdown using siRNA, or dominant negative AMPKα recombinant adenovirus. Finally, we found that TFMG functionally abrogates CRPC development in mouse model. In summary, TFMG exerted vasodilatation through activating Tie2/AMPK/eNOS signaling in endothelial cells, which leads to the overcoming vasoconstriction induced ADT. This study provides the potential value of TFMG in vasodilation of blood vessels leading suppression of CRPC development. Citation Format: You Mie Lee, Ji-Hak Jeong, Hyunha Jang, Jihye You. Tie2-mediated AMPK activation by ferritin-based protein C nanoparticles inhibits advanced prostate cancer development through induction of vasodilation [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 6160.