Project description:Aberrant tyrosine kinase activity can influence tumor growth and is regulated by phosphorylation. Pancreatic ductal adenocarcinoma (PDAC) is a very lethal disease, with minimal therapeutic options. We investigated phosphorylated kinases as target in PDAC. Mass spectrometry-based phosphoproteomic analysis was performed of PDAC cell lines to evaluate active kinases. Pathway analysis and inferred kinase activity was performed to identify novel targets. We investigated targeting of focal adhesion kinase in vitro with drug perturbations in combination with chemotherapeutics used against PDAC. Phosphoproteome analysis upon treatment was performed to evaluate signaling..PDAC cell lines portrayed high activity of multiple receptor tyrosine kinases. Non-receptor kinase, focal adhesion kinase (FAK), was identified in all cell lines by our phosphoproteomic screen and pathway analysis. Targeting of this kinase with defactinib validated reduced phosphorylation profiles. Additionally, FAK inhibition had anti-proliferative and anti-migratory effects. Combination with (nab-)paclitaxel had a synergistic effect on cell proliferation in vitro and reduced tumor growth in vivo. In conclusion, our study shows a high phosphorylation of several oncogenic receptor tyrosine kinases in PDAC cells and validated FAK inhibition as potential synergistic target with Nab-paclitaxel
Project description:Cancer-associated fibroblasts (CAFs), although considered as the most abundant pancreatic ductal adenocarcinoma (PDAC) stromal cells playing a critical role in tumor progression and chemoresistance, are not yet directly druggable. Here we report that focal adhesion kinase (FAK) activity (evaluated based on 397 tyrosine phosphorylation level) in CAFs is highly increased compared to its activity in fibroblasts from healthy pancreas. Fibroblastic FAK activity is an independent prognostic marker for disease free and overall survival of PDAC patients (cohort of 120 PDAC samples). Genetic inactivation of FAK within fibroblasts (FAK-kinase-dead, KD) reduces fibrosis and immunosuppressive cell number within primary tumor and dramatically decreases tumor spread. Mechanistically, pharmacologic and genetic fibroblastic FAK inactivation reduces fibroblast migration/invasion, decreases extracellular matrix (ECM) expression and deposition by CAFs, and negatively impacts M2 macrophage polarization and migration. Thus, FAK activity within CAFs appears as an independent PDAC prognostic marker and a druggable driver of tumor cell invasion.
Project description:Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive cancers with a high level of liver metastasis. Despite substantial advances, resistance to therapy, including gemcitabine, is still a major obstacle to improved progression free survival. Recent studies have indicated that endothelial cell (EC) focal adhesion kinase (FAK) regulates DNA-damaging therapy induced angiocrine factors and chemosensitivity in malignant cells. However, the effect of EC-FAK regulated angiocrine signalling in chemosensitivity of metastatic PDAC remains unexplored. Here, we show that inducible loss of EC-FAK in both orthotopic and spontaneous mouse models of PDAC reduces liver metastasis and improves survival rates in gemcitabine treated, but not untreated, mice, without affecting primary tumour growth, tumour vascularization, blood vessel leakage or early metastatic events. Phosphoproteomics analysis show a downregulation of the MAPK/ RAF/ PAK signalling pathways in gemcitabine treated FAK-depleted ECs compared to gemcitabine treated WT ECs. Moreover, low levels of EC-FAK correlate with increased survival and reduced relapse in gemcitabine treated human PDAC patients, supporting the clinical relevance of our findings. Altogether, we have identified a new role of EC-FAK regulating PDAC liver metastasis upon gemcitabine treatment that impacts on survival.
Project description:Immunotherapeutics represent highly promising agents with the potential to improve patient outcomes in a variety of cancer types. Unfortunately, single-agent immunotherapy has achieved limited clinical benefit to date in patients suffering from pancreatic ductal adenocarcinoma (PDAC). This may be due to the presence of a uniquely immunosuppressive tumor microenvironment (TME) present in PDACs, which creates a barrier to effective immune surveillance. Critical obstacles to immunotherapy in PDAC tumors include the dense desmoplastic stroma that acts as a barrier to T-cell infiltration and the high numbers of tumor-associated immunosuppressive cells. We have identified hyperactivated focal adhesion kinase (FAK) activity in neoplastic PDAC cells as a significant regulator of the fibrotic and immunosuppressive TME. We found that FAK activity was elevated in human PDAC tissues and correlates with high levels of fibrosis and poor CD8+ cytotoxic T-cell infiltration. Single-agent FAK inhibition (VS-4718) dramatically limited tumor progression, resulting in a doubling of survival in the p48-Cre/LSL-KrasG12D/p53Flox/+ (KPC) mouse model of human PDAC. This alteration in tumor progression was associated with dramatically reduced tumor fibrosis, decreased numbers of tumor-infiltrating immature myeloid cells and immunosuppressive macrophages. We postulated that these desirable effects of FAK inhibition on the TME might render PDAC tumors more sensitive to immunotherapy. Accordingly, we found that VS-4718 rendered the previously unresponsive KPC mouse model responsive to anti-PD1 and anti-CTLA4 antagonists leading to a nearly tripling of survival times. These data suggest that FAK inhibition increases immune surveillance by overcoming the fibrotic and immunosuppressive PDAC TME thus rendering tumors more responsive to immunotherapy. We treated KP orthotopic tumor-bearing mice with vehicle and FAK inhibitor (FAKi) for 14 days, then extracted total RNA from tumor tissues.
Project description:Single-agent immunotherapy has achieved limited clinical benefit to date in patients with pancreatic ductal adenocarcinoma (PDAC). This may be a result of the presence of a uniquely immunosuppressive tumor microenvironment (TME). Critical obstacles to immunotherapy in PDAC tumors include a high number of tumor-associated immunosuppressive cells and a uniquely desmoplastic stroma that functions as a barrier to T cell infiltration. We identified hyperactivated focal adhesion kinase (FAK) activity in neoplastic PDAC cells as an important regulator of the fibrotic and immunosuppressive TME. We found that FAK activity was elevated in human PDAC tissues and correlated with high levels of fibrosis and poor CD8+ cytotoxic T cell infiltration. Single-agent FAK inhibition using the selective FAK inhibitor VS-4718 substantially limited tumor progression, resulting in a doubling of survival in the p48-Cre;LSL-KrasG12D;Trp53flox/+ (KPC) mouse model of human PDAC. This delay in tumor progression was associated with markedly reduced tumor fibrosis and decreased numbers of tumor-infiltrating immunosuppressive cells. We also found that FAK inhibition rendered the previously unresponsive KPC mouse model responsive to T cell immunotherapy and PD-1 antagonists. These data suggest that FAK inhibition increases immune surveillance by overcoming the fibrotic and immunosuppressive PDAC TME and renders tumors responsive to immunotherapy.
Project description:Focal adhesion kinase (FAK) is a non-receptor tyrosine kinase that plays an important role in proliferation, motility, adhesion, invasion, angiogenesis, and survival signaling. Focal adhesion kinase has been shown to be overexpressed in many types of tumors, including breast cancer at early stages of tumorigenesis. To study the biological role of FAK in breast tumorigenesis, we used FAKsiRNA to down-regulate FAK in MCF-7 cell lines. Experiment Overall Design: Eight samples were analyzed in MCF-7, MCF-7-Vector, MCF-7 control (luciferase) siRNA and FAKsiRNA#1, FAKsiRNA#2
Project description:Focal adhesion kinase (FAK) is a non-receptor tyrosine kinase that plays an important role in proliferation, motility, adhesion, invasion, angiogenesis, and survival signaling. Focal adhesion kinase has been shown to be overexpressed in many types of tumors, including breast cancer at early stages of tumorigenesis. To study the biological role of FAK in breast tumorigenesis, we used FAKsiRNA to down-regulate FAK in MCF-7 cell lines.
Project description:To further development of our lncRNA and mRNA expression approach to pancreatic ductal adenocarcinoma(PDAC), we have employed lncRNA and mRNA microarray expression profiling as a discovery platform to identify lncRNA and mRNA expression in pancreatic ductal adenocarcinoma.Human pancreatic ductal adenocarcinoma tissues and normal pancreatic tissues from PDAC donors and other duodenum diseases donors. analyze mRNA and lncRNA expression in pancreatic ductal adenocarcinoma (PDAC) by microarray platform
Project description:To explore the potential involvement of circular RNAs (circRNAs) in pancreatic ductal adenocarcinoma (PDAC) oncogenesis, we conducted circRNA profiling in six pairs of human PDAC and adjacent normal tissue by microarray. Our results showed that clusters of circRNAs were aberrantly expressed in PDAC compared with normal samples, and provided potential targets for future treatment of PDAC and novel insights into PDAC biology. Analyze circular RNA expression in pancreatic ductal adenocarcinoma (PDAC) by microarray platform.
Project description:We report KH-type splicing regulatory protein (KHSRP) as a novel m6A reader with oncogenic functions in pancreatic ductal adenocarcinoma (PDAC). KHSRP recognizes and stabilizes its target mRNAs (e.g., MET, ITGAV and ITGB1) in an m6A-dependent manner, therefore activating downstream FAK signaling and promoting PDAC progression. Targeting KHSRP shows promising anti-tumoral effects in vitro and in vivo, indicating that KHSRP may serve as a therapeutic target for PDAC.