Project description:We harvested and sequenced the spontaneous pancreatic tumor generated by a 6-month-old KPC mouse (KrasLSL-G12D; Trp53LSL-R172H; Ptf1a-Cre).
Project description:Bulk RNA sequencing of sorted peri-pancreatic LN cDC1s from different stages of neoplastic development in the KPC mouse model of pancreatic adenocarcinoma.
Project description:To study possible CNVs and genes affected by CNVs in the cancer associated fibroblast populations of pancreatic cancers, we applied single cell sequencing technology (10x Genomics) to identify different subpopulations in murine KPC pancreatic tumors and pancreata of age- and gender-matched non-tumor bearing mice. Single cell RNA sequencing (scRNA-Seq) identified three major CAF subpopulations which were interrogated together with the ductal carcinoma population for CNVs using a previously reported inferCNV algorithm. Fibroblasts and ductal cells identified by scRNA-Seq in normal, uninvolved pancreas were used as reference and inferCNVs in both CAF and ductal carcinoma cells were validated with CNVs previously reported within a large high-resolution array comparative genomic hybridization (aCGH) of KPC tumors. CNVs were exclusively detected in the myelofibroblastic cancer associated fibroblast (myCAF) subpopulation and not in the other CAF phenotypes. In comparison to ductal carcinoma cells, myCAFs were less frequently affected by CNVs. CNVs in the myCAFs which were unique for the myCAFs and not shared with gene loci affected by CNVs in ductal carcinoma cells included known regulators of CAF activation, CAF-mediated cancer cell invasion, or antagonists of TGFβ signaling.
Project description:During carcinoma progression, mesenchymal stromal cells (MSCs) become recruited to tumors and contribute to the pool of cancer-associated fibroblasts (CAFs). Sub-populations of CAFs, have diverse and incompletely understood effects on disease progression and resistance to therapy. Adipose stromal cells (ASCs), the MSCs from fat tissue increasingly recruited by carcinomas in the context of obesity, have been shown to support cancer progression. Here, the roles of perivascular CAFs expressing platelet-derived growth factor receptor beta (Pdgfrb) and of CAFs expressing non-glycanated decorin (ngDCN), a marker of ASCs, were analyzed. We used mice orthotopically grafted with pancreatic ductal adenocarcinoma (KPC) cells. Ablation of cells expressing thymidine kinase under the control of Pdgfrb promoter with ganciclovir resulted in suppression of primary pancreatic tumor growth. However, ablation Pdgfrb+ cells induced spontaneous metastases to the liver. For depletion of ngDCN+ cells, we used a hunter-killer peptide D-CAN, which has been previously reported to induce apoptosis of ASCs and CAFs in mouse models. Here, D-CAN also had a negative effect on pancreatic tumor growth, however, there was no significant effect on metastatic dissemination. Single cell RNA sequencing of tumors demonstrated that targeting of Pdgfrb+ and ngDCN+ stromal cells had distinct effects on sub-populations of CAFs. Endothelial cell and cancer cell survival was decreased by depletion of either Pdgfrb+ or ngDCN+ stroma. However, pathway analysis revealed that depletion of Pdgfrb+ and ngDCN+ stromal cells has different effects on the markers of cancer cell aggressiveness. D-CAN treatment, and to a less extent Pdgfrb+ cell ablation, suppressed macrophage M2 polarization and increased infiltration of cytotoxic T-lymphocytes. This observation, confirmed in the MyCap graft model of prostate cancer, suggested that ablation of ngDCN+ stroma should synergize with immune checkpoint inhibitors. We tested the effect of D-CAN on the efficacy of anti-PD-L1 antibody in the orthotopic KPC model. Compared to D-CAN and anti-PD-L1 antibody alone, combination treatment had a synergistic effect on tumor growth. Importantly, liver metastases were suppressed by the D-CAN / anti-PD-L1 antibody combination, but not by individual agents. We conclude that improved approaches to target mesenchymal stroma in tumors may be effective in combination with immunotherapy.
Project description:This study used 10X Genomics, single-cell RNA-sequencing to examine the cell types present in the KrasLSL-G12D; Trp53LSL-R172H; Pdx1-Cre (KPC) mouse model for pancreatic ductal adenocarcinoma. The study analyzed tumors from 4 different mice. For each tumor, we performed flow sorting to isolate all viable cells, and to isolate a fibroblast-enriched population of cells for single-cell RNA-seq to determine the transcriptomes of individual cells in KPC pancreatic ductal adenocarcinoma tumors.
Project description:Single cell transcriptomes of CD45+ cells from KPC tumor subcutaneous allografts, either treated with PD-1+CTLA-4 checkpoint blockade or treatment-naïve.
