Project description:Pancreatic ductal adenocarcinoma (PDA) is characterized by abundant desmoplasia and poor tissue perfusion. These features are proposed to limit access of therapies to neoplastic cells and blunt treatment efficacy. Indeed, several agents that target the PDA microenvironment promote chemotherapy delivery and improve anti-neoplastic responses in murine models of PDA. Here, we employed the FG-3019 monoclonal antibody directed against the pleiotropic matricellular signaling molecule connective tissue growth factor (CTGF/CCN2). FG-3019 treatment increased PDA cell killing and led to a dramatic tumor response without altering gemcitabine delivery. Microarray expression profiling revealed the down-regulation by FG-3019 of several anti-apoptotic transcripts, including the master regulator Xiap, down-regulation of which has been shown to sensitize PDA to gemcitabine. Decreases in XIAP protein by FG-3019 in the presence and absence of gemcitabine were confirmed by immunoblot, while increases in XIAP protein were seen in PDA cell lines treated with recombinant CTGF. Therefore, alterations in survival cues following targeting of tumor microenvironmental factors may play an important role in treatment responses in animal models and, by extension, PDA patients. Total RNA was isolated from KPC mouse PDA tumors 9 days after initiation of treatment with IgG (n=7 biological replicates), FG-3019 (n=5), IgG + gemcitabine (n=6), or FG-3019 + gemcitabine (n=6) and hybridized to Affymetrix 430A 2.0 microarrays. CEL files were processed by GC-RMA and rescaled using median per-gene normalization in GeneSpring GX 7.3.1.
Project description:Pancreatic ductal adenocarcinoma (PDAC) continues to be a major health problem. A ketogenic diet (KD), characterized by a very low carbohydrate and high fat composition, has gained attention for its anti-tumor potential. We evaluated the effect and mechanisms of feeding a strict KD alone or in combination with gemcitabine in the autochthonous LSL-KrasG12D/+; LSL- Trp53 R172H/+; Pdx1-Cre (KPC) mouse model. For this purpose, both male and female pancreatic tumor-bearing KPC mice were allocated to a control diet (CD; %kcal: 70% carb, 14% protein, 16% fat), a KD (%kcal: 14% protein, 1% carb, 85% fat), a CD + gemcitabine (CG), or a KD + gemcitabine (KG) group. Mice fed a KD alone or in combination with gemcitabine showed significantly increased blood β-hydroxybutyrate levels compared to mice fed a CD or CG. KPC mice fed a KG had a significant increase in overall median survival compared to KPC mice fed a CD (increased overall median survival by 42%). Interestingly, when the data was disaggregated by sex, the effect of a KG was significant in female KPC mice (60% increase in median overall survival), but not in male KPC mice (28% increase in median overall survival). Mechanistically, the enhanced survival response to a KD combined with gemcitabine was multifactorial, including inhibition of ERK and AKT pathways, regulation of fatty acid metabolism and the modulation of the gut microbiota. In summary, a KD in combination with gemcitabine appears beneficial as a treatment strategy in PDAC in KPC mice, deserving further clinical evaluation.
Project description:Gemcitabine constitutes one of the backbones for chemotherapy treatment in pancreatic ductal adenocarcinoma (PDAC) but patients often show poor or complete lack of response to this agent. Molecular markers downstream of Gemcitabine treatment in pre-clinical models may provide an insight into resistance mechanisms. We identified potential secretory biomarkers of Gemcitabine resistance (response) in the transgenic KRasG12D; Trp53R172H; Pdx-1 Cre (KPC) mouse model of PDAC using cytokine arrays. We validated the oncogenic role of the cytokine tissue inhibitor of matrix metalloproteinases 1 (TIMP-1) in primary pancreatic tumours and metastasis using both in vitro techniques and animal models. We identified potential pathways affected downstream of TIMP-1 using the Illumina Human H12 array. Our findings were validated in both primary and metastatic models of pancreatic cancer. Gemcitabine increases inflammatory cytokines including TIMP-1 in the KPC mouse model. TIMP-1 is upregulated in patients with pancreatic intraepithelial neoplasias grade 3 and PDAC lesions relative to matched normal pancreatic tissue. Additionally, we demonstrate that TIMP-1 plays a role in tumour proliferation and angiogenesis, while inhibition resensitises to gemcitabine and radiotherapy. Strikingly, serum TIMP-1 levels support the formation of liver metastasis through the recruitment of immunosuppressive cell populations, such as CD11b+Gr1+ myeloid cells and CD4+CD25+FOXP3+ Tregs to the hepatic microenvironment. Gemcitabine treatment results in upregulation of the pro-tumourigenic/pro-metastatic cytokine TIMP-1, which partially explains the therapeutic resistance and poor responses to this therapy in PDAC. Our study provides a rationale for the development and testing of TIMP-1 specific inhibitors in addition to chemo/radiotherapy.
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:We investigated the genetic profiles of IL33 and PD1-treated group 2 innate lymphoid cells (ILC2) harvested from KPC tumors and draining lymph nodes in a pancreatic ductal adenocarcinoma (PDAC) mouse model.
Project description:The goal of this study is to investigate the molecular mechanisms of LIF action on pancreatic cancer cells in the classical pancreatic ductal adenocarcinoma mouse model KrasLSL-G12D;Tp53f/f;Rosa26LSL-Luc;Pdx1-Cre mice EpCAM+ pancreatic cancer cells were isolated from pancreatic tumors developped in KrasLSL-G12D;Tp53f/f;Rosa26LSL-Luc;Pdx1-Cre mice treated with either gemcitabine plus control IgG or gemcitabine plus anti-LIF antibody by FACS
Project description:Gemcitabine has been a first-line therapeutic agent for pancreatic ductal adenocarcinoma (PDAC) pancreatic cancer; however, acquisition of resistance to gemcitabine remains a major challenge. We analyzed miRNAs expression profiles by array-based miRNAs analysis between gemcitabine–resistant (PANC-1/GEM) and parental PANC-1 cells.
Project description:No reliable predictors of susceptibility to gemcitabine chemotherapy exist in pancreatic ductal adenocarcinoma. MicroRNAs (miR) are epigenetic gene regulators with tumorsuppressive or oncogenic roles in various carcinomas. This study assesses chemoresistant PDAC for its specific miR expression pattern. Gemcitabine-resistant variants of two mutant p53 human pancreatic adenocarcinoma cell lines were established. MicroRNA screening was investigated by microarray.
Project description:This study used 10X Genomics, single-cell RNA-sequencing to examine the differentiation states of cancer cells present in tumors derived from the KrasLSL-G12D; Trp53LSL-R172H; Pdx1-Cre (KPC) mouse model of pancreatic ductal adenocarcinoma. The study analyzed tumors from 8 different mice.