Background: Profound chemoresistance remains an intractable obstacle in pancreatic cancer treatment. Pancreatic cancer stem cells (CSCs) and the ubiquitous hypoxic niche have been proposed to account for drug resistance. However, the mechanism involved requires further exploration. This study investigated whether the hypoxic niche enhances gemcitabine-induced stemness and acquired resistance in pancreatic cancer cells by activating the AKT/Notch1 signaling cascade. The therapeutic effects of blockading this signaling cascade on gemcitabine-enriched CSCs were also investigated.
Methods: The expression levels of CSC-associated markers Bmi1 and Sox2 as well as those of proteins involved in AKT/Notch1 signaling were measured by Western blot analysis. The expression level of the pancreatic CSC marker CD24 was measured by flow cytometry. Change in gemcitabine sensitivity was evaluated by the MTT assay. The ability of sphere formation was tested by the sphere-forming assay in stem cell medium. The ability of migration and invasion was detected by the transwell migration/invasion assay. A mouse xenograft model of pancreatic cancer was established to determine the effect of Notch1 inhibition on the killing effect of gemcitabine in vivo. The ability of metastasis was investigated by an in vivo lung metastasis assay.
Results: Gemcitabine promoted pancreatic cancer cell stemness and associated malignant phenotypes such as enhanced migration, invasion, metastasis, and chemoresistance. The AKT/Notch1 signaling cascade was activated after gemcitabine treatment and mediated this process. Blockading this pathway enhanced the killing effect of gemcitabine in vivo. However, supplementation with hypoxia treatment synergistically enhanced the AKT/Notch1 signaling pathway and collaboratively promoted gemcitabine-induced stemness.
Conclusions: These findings demonstrate a novel mechanism of acquired gemcitabine resistance in pancreatic cancer cells through induction of stemness, which was mediated by the activation of AKT/Notch1 signaling and synergistically aggravated by the ubiquitous hypoxic niche. Our results might provide new insights for identifying potential targets for reversing chemoresistance in patients with pancreatic cancer.
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http://dx.doi.org/10.1186/s13046-018-0972-3 | DOI Listing |
HPB (Oxford)
December 2024
Institute for Surgical Pathology, Medical Center - University of Freiburg, Germany; Core Facility for Histopathology and Digital Pathology, University of Freiburg, Germany; Faculty of Medicine, University of Freiburg, Germany. Electronic address:
Background: In pancreatic surgery Postoperative pancreatic fistula (POPF) represents the most dreaded complication, for which pancreatic texture is acknowledged as one of the strongest predictors. No consensual objective reference has been defined to evaluate the pancreas composition. The presented study aimed to mine histology data of the pancreatic tissue composition with AI assist and correlate it with clinic-pathological parameters derived from the RECOPANC study.
View Article and Find Full Text PDFGastrointest Endosc
January 2025
Division of Digestive and Liver Diseases, University of Texas Southwestern Medical Center, Dallas, TX. Electronic address:
Background & Aims: Pancreatic cysts often pose challenges in predicting malignant progression. Next-generation sequencing has become an appealing ancillary diagnostic test. The diagnostic performance is well characterized, but the impact on clinical management remains unclear.
View Article and Find Full Text PDFInt Immunopharmacol
January 2025
Division of Pancreatic Surgery, Department of General Surgery, West China Hospital, Sichuan University, Chengdu, Sichuan CN 610041, China. Electronic address:
Chronic pancreatitis (CP) is a clinical entity characterized by progressive inflammation and irreversible fibrosis of the pancreas, which ultimately leads to exocrine and/or endocrine insufficiency as well as an increased risk of pancreatic cancer. Currently, there are no specific or effective approved therapies for CP. Herein, we show that macrophage to myofibroblast transdifferentiation (MMT) and M2 macrophage polarization are associated with both human CP and CP experimental mouse models.
View Article and Find Full Text PDFNeoplasia
January 2025
Children's Cancer Institute, Lowy Cancer Research Centre, University of New South Wales, Sydney, NSW 2031, Australia; School of Clinical Medicine, Faculty of Medicine & Health, University of New South Wales, Kensington, New South Wales 2031, Australia; UNSW Centre for Childhood Cancer Research, Faculty of Medicine &Health, University of New South Wales, Kensington, New South Wales 2031, Australia; Australian Centre for NanoMedicine, University of New South Wales, Sydney, NSW 2031, Australia. Electronic address:
Introduction: The impact of endoplasmic reticulum (ER) stress in tumor-associated cells, such as cancer associated fibroblasts (CAFs), immune cells and endothelial cells, on patient outcomes in clinical specimens have not been examined. For the first time, we characterized the expression and spatial locations of ER stress markers, BiP and CHOP, in tumor-associated cells and assessed their prognostic significance in a panel of pancreatic ductal adenocarcinoma (PDAC) patient samples.
Methods: Multiplex immunofluorescence was performed on tumor microarrays and images were analyzed using HALO AI software.
Ann Med
December 2025
Department of Surgery, Faculty of Medicine, Unit of Hepato-Pancreato-Biliary Surgery and Abdominal Organ Transplantation, Doce de Octubre University Hospital, Instituto de Investigación (imas12), Complutense University, Madrid, Spain.
Background: Delayed gastric emptying (DGE) is a frequent complication of pancreatoduodenectomy (PD) and is associated with prolonged hospital stay, readmission, increased hospital costs and decreased quality of life. However, the pathophysiology of DGE remains unclear.
Methods: This is a retrospective study of patients who underwent PD for pancreatic or periampullary tumours.
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