Project description:Background & Aims: Pancreatic ductal adenocarcinomas (PDAC) are characterized by fibrosis and an abundance of cancer-associated fibroblasts (CAFs). We investigated strategies to disrupt interactions among CAFs, the immune system, and cancer cells, focusing on adhesion molecule cadherin 11 (CDH11), which has been associated with other fibrotic disorders and is expressed by activated fibroblasts. Methods: We compared levels of CDH11 mRNA in human pancreatitis and pancreatic cancer tissues and cells, compared with normal pancreas, and measured levels of CDH11 protein in human and mouse pancreatic lesions and normal tissues. We crossed p48-Cre;LSL-KrasG12D/+;LSL-Trp53R172H/+ (KPC) mice with CDH11-knockout mice and measured survival times of offspring. Pancreata were collected and analyzed by histology, immunohistochemistry, and (single-cell) RNA sequencing; RNA and proteins were identified by imaging mass cytometry. Some mice were given injections of PD1 antibody or gemcitabine and survival was monitored. Pancreatic cancer cells from KPC mice were subcutaneously injected into Cdh11+/+ and Cdh11–/– mice and tumor growth was monitored. Pancreatic cancer cells (mT3) from KPC mice (C57BL/6), were subcutaneously injected into Cdh11+/+ (C57BL/6J) mice and mice were given injections of antibody against CDH11, gemcitabine, or small molecule inhibitor of CDH11 (SD133) and tumor growth was monitored. Results: Levels of CDH11 mRNA and protein were significantly higher in CAFs than in pancreatic cancer epithelial cells, human or mouse pancreatic cancer cell lines, or immune cells. KPC/Cdh11+/– and KPC/Cdh11–/– mice survived significantly longer than KPC/Cdh11+/+ mice. Markers of stromal activation entirely surrounded pancreatic intraepithelial neoplasias in KPC/Cdh11+/+ mice and incompletely in KPC/Cdh11+/– and KPC/Cdh11–/– mice, whose lesions also contained fewer FOXP3+ cells in the tumor center. Compared with pancreatic tumors in KPC/Cdh11+/+ mice, tumors of KPC/Cdh1+/– mice had increased markers of antigen processing and presentation; more lymphocytes and cytokines associated with lymphocyte infiltration; decreased extracellular matrix components; and reductions in markers and cytokines associated with immunosuppression. Administration of the PD1 antibody did not prolong survival of KPC mice with 0, 1, or 2 alleles of Cdh11. Gemcitabine extended survival only of KPC/Cdh11+/– and KPC/Cdh11–/– mice or reduced subcutaneous tumor growth in mT3 engrafted Cdh11+/+ mice given in combination with the CDH11 antibody. A small molecule inhibitor of CDH11 reduced growth of pre-established mT3 subcutaneous tumors only if T and B cells were present in mice. Conclusions: Knockout or inhibition of CDH11, which is expressed by CAFs in the pancreatic tumor stroma, reduces growth of pancreatic tumors, increases their response to gemcitabine, and significantly extends survival of mice. CDH11 promotes immunosuppression and extracellular matrix deposition, and might be developed as a therapeutic target for pancreatic cancer.
Project description:BACKGROUND & AIMS: Acinar cells produce digestive enzymes that impede transcriptomic characterization of the exocrine pancreas. Thus, single-cell RNA-sequencing (scRNA-seq) studies of the pancreas underrepresent acinar cells relative to histological expectations, and a robust approach to capture pancreatic cell responses in disease states is needed. We sought to innovate a method that overcomes these challenges to accelerate study of the pancreas in health and disease. METHODS: We introduce FixNCut, a scRNA-seq approach where tissue is reversibly fixed with dithiobis(succinimidyl propionate) prior to dissociation and single-cell preparation. We apply FixNCut to an established mouse model of acute pancreatitis, validate findings using GeoMx whole transcriptome atlas (WTA) profiling, and integrate our data with prior studies to benchmark our method in both mouse and human pancreas datasets. RESULTS: FixNCut achieves unprecedented definition of challenging pancreatic cells including acinar and immune populations in homeostasis and acute pancreatitis, and identifies changes in all major cell types during injury and recovery. We define the acinar transcriptome during homeostasis and acinar-to-ductal metaplasia and establish a unique gene set to measure deviation from normal acinar identity. We characterize pancreatic immune cells, and analysis of T-cell subsets reveals a polarization of the homeostatic pancreas towards type-2 immunity. We report immune responses during acute pancreatitis and recovery, including early neutrophil infiltration, expansion of dendritic cell subsets, and a substantial shift in the transcriptome of macrophages due to both resident macrophage activation and monocyte infiltration. CONCLUSIONS: FixNCut preserves pancreatic transcriptomes to uncover novel cell states during homeostasis and following pancreatitis, establishing a broadly applicable approach and reference atlas for study of pancreas biology and disease.
Project description:An Epigenetic Memory of Inflammation Induces Context-Dependent Lineage Plasticity in the Pancreas with Divergent Phenotypic Outcomes [Acute Pancreatitis scRNA-seq]
Project description:BACKGROUND & AIMS: Pancreatic ductal adenocarcinoma (PDAC) is usually incurable. Contrary to genetic mechanisms involved in PDAC pathogenesis, epigenetic alterations are ill defined. Here we determine the contribution of epigenetically silenced genes to the development of PDAC. METHODS: We investigated methylated DNAs from PDACs, chronic pancreatitis and normal pancreatic tissues using Methyl-CpG immunoprecipitation followed by microarray hybridization. Promoter methylation of selected genes was confirmed with the Epityper assay. Expression levels were evaluated by quantitative RT-PCR. WNK2 was further investigated in tissue microarrays, methylation analysis of early pancreatic intraepithelial neoplasia (PanINs), mouse models for PDAC and pancreatitis, re-expression studies after demethylation, and cell growth assays using WNK2 overexpression. RESULTS: A total of 3.8% of 27.800 interrogated CpG islands were hypermethylated in PDAC versus normal and chronic pancreatitis tissues. Hypermethylation was confirmed in 12 out of 13 selected islands and was associated with gene silencing in 4 of them. The most prominently hypermethylated gene, WNK2, was further investigated. Demethylation assays confirmed the link between methylation and expression. WNK2 hypermethylation was higher in pancreatic tumor cells than in surrounding inflamed tissues and was observed in PanIN lesions as well as in a PDAC mouse model. WNK2 mRNA and protein expression were lower in PDAC and chronic pancreatitis compared to normal tissues both in patients and mouse models. Overexpression of WNK2 led to a reduced cell growth and WNK2 expression in tissues correlated negatively with the expression of pERK1/2, a downstream target of WNK2 responsible for cell proliferation. CONCLUSIONS: WNK2 is downregulated by promoter hypermethylation early in PDAC pathogenesis and may support tumor cell growth via the ERK-MAPK pathway. 3 types of pancreatic tissue samples: 5 normals, 2 chronic pancreatitis, 7 tumors (PDAC)
Project description:A total of 16 clinical samples from ductal adenocarcinoma, 6 samples from chronic pancreatitis, and 4 samples from morphologically normal resection margins from chronic pancreatitis resectates were analyzed.
Project description:NP_total or SP_total stand for normal or acute pancreatitis proteome data respectively. NP_phospho or SP_phospho stand for normal or acute pancreatitis phosphoproteome data respectively.
Project description:Pancreatic ductal adenocarcinoma (PDAC) causes involuntary wasting of adipose and muscle tissue, also known as cachexia. Cachexia is a major cause of cancer-related deaths, particularly among patients with PDAC. Here we profiled gene expression in adipose tissue and skeletal muscle in normal/sham control mice and in mice bearing orthotopic PDAC tumors. PDAC tumors were initiated by intra-pancreatic injection of a cell line derived from the KPC (Kras-G12D;Trp-R172H;Pdx1::Cre) genetically engineered mouse model of pancreatic cancer, or by injection of the same cell line deleted for the IL6 gene using CRISPR/Cas9. KPC-IL6 knockout (ko) cells caused less adipose wasting and no muscle loss compared with KPC-wildtype (wt) cells.
Project description:To examine the effect of AC484 inhibition on the tumor immune microenvironment, we performed scRNA-seq on CD45+ cells from B16 and KPC tumors from mice treated with vehicle, anti-PD-1, or AC484.
Project description:Pancreatic cancer is among the deadliest cancers that affects almost 54,000 patients in United States alone, with 90% of them succumbing to the disease. Lack of early detection is considered to be the foremost reason for such dismal survival rates. Our study shows that resident gut microbiota is altered at the early stages of tumorigenesis much before development of observable tumors in a spontaneous, genetically engineered mouse model for pancreatic cancer. In the current study, we analyzed the microbiome of in a genetic mouse model for PDAC (KRASG12DTP53R172HPdxCre or KPC) and age-matched controls using WGS at very early time points of tumorigenesis. During these time points, the KPC mice do not show any detectable tumors in their pancreas. Our results show that at these early time points, the histological changes in the pancreas correspond to a significant change in certain gut microbial population. Our predictive metabolomic analysis on the identified bacterial species reveal that the primary microbial metabolites involved in progression and development of PDAC tumors are involved in polyamine metabolism.