Metabolic reprogramming via statin repurposing: A strategy to reverse the Warburg effect and overcome gemcitabine resistance in pancreatic ductal adenocarcinoma

Background: Pancreatic ductal adenocarcinoma (PDAC) remains among the deadliest cancers, with mortality projected to rank second in cancer-related deaths by 2030. Gemcitabine is a first-line chemotherapy, but resistance frequently develops, leading to poor prognosis. Metabolic reprogramming, particularly enhanced glycolysis driven by hypoxia and HIF-1alpha activation, is a key mechanism of gemcitabine resistance. Statins, commonly used cholesterol-lowering drugs that inhibit HMG-CoA reductase, have demonstrated potential metabolic and anti-cancer effects with an established safety profile. This study investigated whether statins could overcome gemcitabine resistance in PDAC by targeting glycolytic adaptation. Methods: Gemcitabine-resistant PDAC cell lines (MIA PaCa-2 and BxPC-3) and patient-derived 3D organoids were treated with simvastatin alone or combined with gemcitabine. Outcomes included cell viability, apoptosis, migration, invasion, and glycolytic activity (measured by extracellular acidification rate [ECAR] and lactate production). Expression of glycolysis-related genes HIF-1alpha, HK2, and LDHA was measured by RT-qPCR and Western blotting. Pharmacological modulation of HIF-1alpha was used to validate the mechanism. Clinical significance was assessed via EUS-FNA samples from 50 patients with PDAC treated with Gemcitabine and transcriptomic data from The Cancer Genome Atlas (TCGA). Results: Simvastatin reduced the viability of Gemcitabine-resistant PDAC cells compared with parental cell lines (IC50: 20-21 μM vs. 37-39 μM in parental cells; p <0.01) and showed synergy with Gemcitabine (Bliss scores: 5.5 and 4.29) and markedly enhanced anti-tumor activity, reducing viability by 41.7% and 44.4%, respectively. The combination significantly suppressed migration and invasion and increased apoptosis ( p <0.001), accompanied by increased cleaved PARP and caspase-3. Resistant cells exhibited elevated glycolysis, and simvastatin, especially in combination with Gemcitabine, reduced lactate, ECAR, and expression of HIF-1alpha, HK2, and LDHA at both mRNA and protein levels ( p <0.01), mimicking HIF-1alpha inhibition. In two PDAC organoids, combination therapy disrupted structure and reduced viability while downregulating glycolytic genes. Clinically, high HIF-1alpha/HK2/LDHA expression correlated with Gemcitabine nonresponse and worse PFS/OS in both our gemcitabine-treated cohort and TCGA dataset. Conclusion: Statins restore gemcitabine sensitivity in PDAC by suppressing HIF-1alpha-driven glycolytic reprogramming, reversing the metabolic adaptations responsible for chemoresistance. With their proven safety, affordability, and wide availability, statins offer a promising, immediately translatable approach to improve outcomes in gemcitabine-resistant PDAC.