RESUMEN
Pancreatic adenocarcinoma is the fourth leading cause of malignancy-related deaths, with rapid development of drug resistance driven by pancreatic cancer stem cells. However, the mechanisms sustaining stemness and chemotherapy resistance in pancreatic ductal adenocarcinoma (PDAC) remain unclear. Here, we demonstrate that Bicaudal C homolog 1 (BICC1), an RNA binding protein regulating numerous cytoplasmic mRNAs, facilitates chemoresistance and stemness in PDAC. Mechanistically, BICC1 activated tryptophan catabolism in PDAC by up-regulating indoleamine 2,3-dioxygenase-1 (IDO1) expression, a tryptophan-catabolizing enzyme. Increased levels of tryptophan metabolites contribute to NAD+ synthesis and oxidative phosphorylation, leading to a stem cell-like phenotype. Blocking BICC1/IDO1/tryptophan metabolism signaling greatly improves the gemcitabine (GEM) efficacy in several PDAC models with high BICC1 level. These findings indicate that BICC1 is a critical tryptophan metabolism regulator that drives the stemness and chemoresistance of PDAC and thus a potential target for combinatorial therapeutic strategy against chemoresistance.
Asunto(s)
Resistencia a Antineoplásicos , Células Madre Neoplásicas , Neoplasias Pancreáticas , Triptófano , Triptófano/metabolismo , Humanos , Resistencia a Antineoplásicos/genética , Células Madre Neoplásicas/metabolismo , Células Madre Neoplásicas/patología , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/tratamiento farmacológico , Línea Celular Tumoral , Animales , Ratones , Regulación Neoplásica de la Expresión Génica , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/patología , Carcinoma Ductal Pancreático/tratamiento farmacológico , Carcinoma Ductal Pancreático/genética , Gemcitabina , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacología , Proteínas de Unión al ARN/metabolismo , Proteínas de Unión al ARN/genética , Indolamina-Pirrol 2,3,-Dioxigenasa/metabolismo , Indolamina-Pirrol 2,3,-Dioxigenasa/genéticaRESUMEN
Rapid development of drug resistance after chemotherapy is a major cause of treatment failure in individuals with pancreatic ductal adenocarcinoma (PDAC). In this study, we illustrate that tumor-derived interleukin 35 (IL-35) mediates the accelerated resistance of PDAC to gemcitabine (GEM). We observe that GEM resistance can spread from GEM-resistant PDAC cells to GEM-sensitive cells, and that IL-35 is responsible for the propagation of chemoresistance, which is supported by sequencing and experimental data. Additionally, we discover that GEM-resistant cells have significantly higher levels of IL-35 expression. Mechanistically, aberrantly expressed IL-35 triggers transcriptional activation of SOD2 expression via GP130-STAT1 signaling, scavenging reactive oxygen species (ROS) and leading to GEM resistance. Furthermore, GEM treatment stimulates IL-35 expression through activation of the NF-κB pathway, resulting in acquired chemoresistance. In the mouse model, a neutralizing antibody against IL-35 enhances the tumor suppressive effect of GEM. Collectively, our data suggests that IL-35 is critical in mediating GEM resistance in pancreatic cancer, and therefore could be a valuable therapeutic target in overcoming PDAC chemoresistance.
