Aims/hypothesis: The Edmonton Protocol for islet transplantation has provided hope for type 1 diabetic patients. However, this protocol requires lifelong immunosuppression, specifically sirolimus, a cellular antiproliferate. The effect of sirolimus on human pancreatic ductal cells (HDCs) is not known. This may be important since HDCs are believed to be islet precursors. Since neonatal porcine islets (NPIs), which contain many ductal precursor cells, could be a potential clinical source of islets, we also tested the effects of sirolimus on this tissue.
Methods: HDCs (n=4), NPIs (n=9) and human islets (n=5) were cultured with and without sirolimus (20 ng/ml) for 6 days.
Results: HDCs and NPIs cultured with sirolimus showed a 50 and 28% decrease, respectively, in cell number relative to control (p<0.05). Control cultures expanded 1.65- and 2.44-fold relative to time 0. Decreases in cell number of sirolimus-treated HDCs were not due to apoptosis as measured by TUNEL staining. No functional effects on human islets or NPIs were observed following static incubation with high glucose. Treatment of syngeneically transplanted and naïve BALC/c mice with sirolimus resulted in altered OGTT profiles with prolonged elevation of hyperglycaemia and weight gain. There was no difference in graft and organ insulin content between treatment groups.
Conclusions/interpretation: Our results indicate that sirolimus decreases ductal cell numbers in culture and alters glucose-stimulated insulin secretion in vivo. The administration of sirolimus to islet transplant recipients is likely to impair graft function as a result of decreasing ductal neogenesis and induction of insulin resistance.
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http://dx.doi.org/10.1007/s00125-006-0374-5 | DOI Listing |
J Clin Invest
January 2025
Department of Hepatobiliary and Pancreatic Surgery, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China.
Metabolic reprogramming shapes tumor microenvironment (TME) and may lead to immunotherapy resistance in pancreatic ductal adenocarcinoma (PDAC). Elucidating the impact of pancreatic cancer cell metabolism in the TME is essential to therapeutic interventions. "Immune cold" PDAC is characterized by elevated lactate levels resulting from tumor cell metabolism, abundance of pro-tumor macrophages, and reduced cytotoxic T cell in the TME.
View Article and Find Full Text PDFFront Immunol
January 2025
Department of Hepatobiliary Surgery, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China.
Background: Damage-associated molecular patterns (DAMPs) induced by immunogenic cell death (ICD) may be useful for the immunotherapy to patients undergoing pancreatic ductal adenocarcinoma (PDAC). The aim of this study is to predict the prognosis and immunotherapy responsiveness of PDAC patients using DAMPs-related genes.
Methods: K-means analysis was used to identify the DAMPs-related subtypes of 175 PDAC cases.
Cell Rep Med
January 2025
State Key Laboratory of Systems Medicine for Cancer, Stem Cell Research Center, Ren Ji Hospital, Shanghai Cancer Institute, Shanghai Jiao Tong University School of Medicine, Shanghai, China. Electronic address:
Pancreatic ductal adenocarcinoma (PDAC) relies heavily on glutamine (Gln) utilization to meet its metabolic and biosynthetic needs. How epigenetic regulators contribute to the metabolic flexibility and PDAC's response and adaptation to Gln scarcity in the tumor milieu remains largely unknown. Here, we elucidate that prolonged Gln restriction or treatment with the Gln antagonist, 6-diazo-5-oxo-L-norleucine (DON), leads to growth inhibition and ferroptosis program activation in PDAC.
View Article and Find Full Text PDFSci Transl Med
January 2025
Department of Surgery, UT Southwestern Medical Center, Dallas, TX 75390, USA.
Pancreatic ductal adenocarcinoma (PDAC) driven by the mutation presents a formidable health challenge because of limited treatment options. MRTX1133 is a highly selective and first-in-class KRAS-G12D inhibitor under clinical development. Here, we report that the advanced glycosylation end product-specific receptor (AGER) plays a key role in mediating MRTX1133 resistance in PDAC cells.
View Article and Find Full Text PDFAcute pancreatitis (AP) is a life-threatening condition, with a higher mortality rate in men than women and in which estrogens might play a protective role. This study aimed to investigate sex-dependent differences in a mouse model of caerulein-induced AP. Thirty-six C57BL/6J mice (19 females and 17 males) were treated intraperitoneally with phosphate-buffered saline or caerulein, and sacrificed 12 hours, 2 days, or 7 days after the last injection.
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