Niclosamide nanoparticles enhance pancreatic cancer sensitivity to gemcitabine via HIF-1α inhibition

Pancreatic cancer (PC) exhibits profound metabolic adaptations that support tumor progression, survival, and therapy resistance. Hypoxia-inducible factor-1α (HIF-1α) is a key regulator of these processes, promoting metabolic reprogramming and chemoresistance. Given that mitochondrial metabolites modulate HIF-1α stability, targeting mitochondrial metabolism offers a promising therapeutic strategy. Niclosamide (Nic), a clinically approved anthelmintic, disrupts mitochondrial function but is limited by poor bioavailability. To overcome this, we developed polyanhydride-based Nic nanoparticles (NicNps) to enhance bioavailability and efficacy. NicNps impaired mitochondrial function, suppressed metabolism, downregulated HIF-1α, and inhibited growth of PC cells and orthotopic gemcitabine (Gem)-resistant mouse tumor models. Notably, NicNps combined with Gem overcame therapy resistance by synergistically reducing tumor hypoxia and HIF-1α-driven metabolic reprogramming. These findings highlight NicNps as a mitochondria-targeted, nanoparticle-based therapy that enhances Nic's bioavailability while suppressing HIF-1α-driven adaptations. NicNps in combination with Gem offer a promising strategy to overcome therapy resistance and improve treatment outcomes in patients with pancreatic cancer.