Project description:In patients with pancreatic ductal adenocarcinoma (PDAC), we show that response to radiation therapy (RT) is characterized by increased IL2R and IL2R expression, decreased ILR2 and exhaustion markers. The bispecific PD-1-targeted IL-2 variant (IL2v) immunocytokine with engineered IL-2 cis-targeted to PD-1 and abolished IL2R binding targets the activation of tumor-antigen specific T cells while rescuing them from Treg suppression. Using aPD1-IL2v in orthotopic PDAC KPC-driven tumor models, we show marked improvement in local and metastatic survival along with profound increase in tumor-infiltrating polyfunctional CD8 T cell subsets with a transcriptionally and metabolically active phenotype, and preferential activation of antigen-specific CD8 T cells. In combination with single dose RT, aPD1-IL2v treatment results in a robust, durable expansion of polyfunctional CD8 T cells, T cell stemness, tumor-specific memory immune response, NK cell activation, and decreased Tregs. These data show that the novel aPD1-IL2v, leads to profound local and distant response in PDAC.
Project description:PurposeTo provide a detailed description of practical approaches to dose escalation in pancreatic cancer.Methods and materialsThe current paper represents an international collaborative effort of radiation oncologists from the MR-linac consortium with expertise in pancreatic dose escalation.ResultsA 15-fraction hypofractionated intensity modulated radiation therapy (67.5 Gy in 15 fractions) and 5-fraction stereotactic body radiation therapy case (50 Gy in 5 fractions) are presented with information regarding patient selection, target volumes, organs at risk, dose constraints, and specific considerations regarding quality assurance. Additionally, we address barriers to dose escalation and briefly discuss future directions in dose escalation for pancreatic cancer, including particle therapy and magnetic resonance guided radiation therapy.ConclusionsThis article on dose escalation for pancreatic cancer may help to guide academic and community based physicians and to serve as a reference for future therapeutic trials.
Project description:PurposeLocal tumor progression is a cause of significant morbidity and mortality in patients with pancreatic ductal adenocarcinoma (PDAC) with surgically unresectable disease. Novel and effective approaches to accomplish durable local control are urgently needed. We tested whether CPI-613 (devimistat), a first-in-class investigational small molecule inhibitor of mitochondrial metabolism, was capable of altering cancer cell energy metabolism and sensitizing PDAC cells to radiation therapy (RT).Methods and materialsThe effect of a combined treatment of RT with CPI-613 on the viability of, clonogenic potential of, and cell death induction in PDAC cells (MiaPaCa-2 and Panc-1) was determined using a trypan blue dye exclusion assay, a colony formation assay, and a 7-amino-actinomycin D assay, respectively. The synergistic effects of CPI-613-RT and chemotherapeutic agents (gemcitabine or 5-fluorouracil) were measured in MiaPaCa-2 cells using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and spheroid formation assay. Changes in energy metabolism were determined by profiling metabolites treated with either RT, CPI-613, or both using liquid chromatography-mass spectrometry.ResultsThis study demonstrates that a combination of single-fraction RT (2 and 10 Gy) with CPI-613 significantly inhibits PDAC cell growth compared with RT alone. Molecular analysis revealed inhibition of α-ketoglutarate dehydrogenase at the protein level. In addition, we demonstrate enhanced cell death of PDAC cells when treated with RT-CPI-613 combination. Targeted metabolomic analysis on PDAC cells post-CPI-613-RT treatment revealed alterations in key mitochondrial metabolites, with broader target engagement by the combination treatment, indicating the sensitization of CPI-613-treated PDAC cells to RT. Furthermore, a combination treatment of CPI-613 with either gemcitabine or 5-fluorouracil in the presence of 2 Gy RT synergistically inhibits PDAC cell proliferation.ConclusionsOur results support a novel combination of CPI-613-RT that warrants further preclinical and early-phase clinical investigations. A phase 1 trial designed to identify the maximum tolerated dose of CPI-613 in combination with chemo-RT in patients with PDAC was recently initiated (NCT05325281).
Project description:We present the design and synthesis of a small library of substituted biguanidium salts and their capacity to inhibit the growth of pancreatic cancer cells. We first present their in vitro and membrane activity, before we address their mechanism of action in living cells and in vivo activity. We show that phenylethynyl biguanidium salts possess higher ability to cross hydrophobic barriers, improve mitochondrial accumulation and anticancer activity. Mechanistically, the most active compound, 1b, like metformin, activated AMPK, decreased the NAD+/NADH ratio and mitochondrial respiration, but at 800-fold lower concentration. In vivo studies show that compound 1b significantly inhibits the growth of pancreatic cancer xenografts in mice, while biguanides currently in clinical trials had little activity.
Project description:Pancreatic ductal adenocarcinoma (PDAC) is a deadly disease, with its mortality rate approaching its incidence rate every year. Accordingly, much interest has been generated in harnessing the immune system in order to improve survival outcomes for these patients. Pancreatic cancer is not thought to be as immunogenic as other cancers that have seen promising results with immune checkpoint inhibitors alone, therefore likely several targets within the cancer-immunity cycle will need to be employed for successful treatment. We sought to investigate both the current state of the field in immunotherapy in PDAC with a special emphasis on combined approaches with radiation therapy (RT). We also summarized ongoing clinical trials that are examining the use of radiotherapy with other immune-stimulating agents in the treatment of PDAC. A PubMed and clinicaltrials.gov search was conducted using the following search terms, either alone or in combination: "pancreatic cancer", "immunotherapy", and "abscopal effect". Open clinical trials were reviewed and included if they involved both RT and other immune-stimulating agents. Pancreatic cancers tend to reside within immune-suppressive tumor microenvironments (TME), express PD-L1, and secrete several immuno-suppressive agents, such as TGF-B, IL-10, indoleamine 2,3-dioxygenase, galectin-1. Whole-cell vaccine therapies, peptide and protein vaccines, dendritic cell vaccines, and vaccines with micro-organisms have been investigated by themselves with promising results. Open clinical trials are currently investigating the use of these vaccines, which increase antigen presentation, with treatments that stimulate release of tumor antigens including RT. There are currently at least 21 open clinical trials investigating the combination of RT with other immune-stimulating agents. The combination of RT and immunotherapy may be a promising avenue for PDAC treatment and deserves further research.