WITHDRAWN: ROS/KRAS/AMPK signaling determines gemcitabine-induced pancreatic cancer stem-like cell property in vitro

Abstract

Poor prognosis of pancreatic cancer (PanCa) is partially due to chemoresistance to gemcitabine (GEM), the standard chemotherapy. Dysregulated glucose metabolism is revealed to contribute to therapeutic resistance and pluripotent state. Cancer stem cells (CSCs) rewire cellular metabolism to survive the chemotherapeutics and initiate cancer relapse. However, few studies focus on the effect of GEM on cancer cell metabolism, the stemness status, and the involved mechanisms which are crucial in PanCa treatment. In this study, we demonstrate that GEM treatment induces metabolic reprogramming from mitochondrial oxidation to glycolysis and promotes cancer stem-like status. However, inhibition of glycolysis using 2-deoxy-D-glucose (2-DG) suppresses cancer stemness and strengthens the cytotoxicity of GEM. We further demonstrate that GEM-induced metabolic reprogramming is KRASdependent as knockdown of KRAS reverses the metabolic shift. In addition, GEMinduced metabolic reprogramming activates AMP-activated protein kinase (AMPK) which promotes glycolytic flux and cancer stemness. Our results further reveal the involvement of GEM-induced reactive oxygen species (ROS) in the activation of KRAS/ AMPK pathway in regulation of metabolic reprogramming and cancer stemness, while N-acetyl-L-cysteine (NAC), a ROS scavenger, inhibits the activated KRAS/AMPK pathway, which is further validated by introducing exogenous hydrogen peroxide (H 2 O 2). Collectively, these findings reveal an undesired effect of GEM in PanCa treatment. Therefore, regulating cellular redox, targeting KRAS/AMPK signaling, or reversing metabolic reprogramming may be effective approaches to eliminate CSCs and enhance chemosensitivity of GEM to improve the prognosis of patients with PanCa.