Project description:DDR2 regulates collagen production by CAFs in the tumor microenvironment by controlling the transcription of arginase 1, and CAFs are a major source of arginase activity and L-arginine metabolites in ovarian cancer models. We aimed to determine which cell populations are DDR2 and Arg1 positive in the ID8 p53-/- BRCA2-/- tumor model
Project description:Ovarian cancer has poor survival outcomes particularly for advanced stage, metastatic disease. Metastasis is promoted by interactions of stromal cells, such as cancer-associated fibroblasts (CAFs) in the tumor microenvironment (TME), with tumor cells. CAFs play a key role in tumor progression by remodeling the TME and extracellular matrix (ECM) to result in a more permissive environment for tumor progression. It has been shown that fibroblasts, in particular myofibroblasts, utilize metabolism to support ECM remodeling. However, the intricate mechanisms by which CAFs support collagen production and tumor progression are poorly understood. In this study, we show that the fibrillar collagen receptor, Discoidin Domain Receptor 2 (DDR2), promotes collagen production in human and mouse omental CAFs through arginase activity. CAFs with high DDR2 or arginase promote tumor colonization in the omentum. In addition, DDR2-depleted CAFs had decreased ornithine levels leading to decreased collagen production and polyamine levels compared to WT control CAFs. Tumor cell invasion was decreased in the presence CAF conditioned media (CM) depleted of DDR2 or arginase-1, and this invasion defect was rescued in the presence of CM from DDR2-depleted CAFs that constitutively overexpressed arginase-1. Similarly, the addition of exogenous polyamines to CM from DDR2-depleted CAFs led to increased tumor cell invasion. We detected SNAI1 protein at the promoter region of the arginase-1 gene, and DDR2-depleted CAFs had decreased levels of SNAI1 protein at the arginase-1 promoter region. Furthermore, high stromal arginase-1 expression correlated with poor survival in ovarian cancer patients. These findings highlight how DDR2 regulates collagen production by CAFs in the tumor microenvironment by controlling the transcription of arginase-1, and CAFs are a major source of arginase activity and L-arginine metabolites in ovarian cancer models.
Project description:Extracellular matrix (ECM) regulates carcinogenesis. As a major ECM component, collagen interacts with integrin and a non-typical receptor discoidin domain receptor tyrosine kinase 2 (DDR2), but how DDR2 regulates cancer progression is poorly understood. Apart from its signaling function, ECM provides a mechanical environment for cancer, but the impact of biomechanics on cancer remains enigmatic. Here, we performed RNA-seq of a human neuroblastoma cell line SH-SY5Y. We found that DDR2 knockdown, but not increasing substrate stiffness, upregulated pro-proliferative genes and down-regulated axonogenesis genes. Surprisingly, despite no transcriptome changes, increasing of stiffness attenuates SH-SY5Y cell proliferation, an effect also observed after DDR2 knockdown. Our results indicate that two ECM effectors, DDR2 and biomechanics, could control cancer cell proliferation through different mechanisms.
Project description:Single-cell RNA sequencing was performed on injured and uninjured hindlimb tissue of Ddr2 slie/slie mice and littermate controls following 30% total body surface area burn and Achilles’ tenotomy injury to determine the role of DDR2 in heterotopic ossification and aberrant differentiation during wound healing.
Project description:Collagen type XI alpha 1 (COL11A1) is a novel biomarker associated with cisplatin resistance in ovarian cancer. However, the mechanisms underlying how COL11A1 confers cisplatin resistance in ovarian cancer are poorly understood. We identified that fatty acid β-oxidation (FAO) is upregulated by COL11A1 in ovarian cancer cells and that COL11A1-driven cisplatin resistance can be abrogated by inhibition of FAO. Furthermore, our results demonstrate that COL11A1 also enhances the expression of proteins involved in fatty acid synthesis. Interestingly, COL11A1-induced upregulation of fatty acid synthesis and FAO is modulated by the same signaling molecules. We identified that binding of COL11A1 to its receptors, α1β1 integrin and discoidin domain receptor 2 (DDR2), activates Src-Akt-AMPK signaling to increase the expression of both fatty acid synthesis and oxidation enzymes, although DDR2 seems to be the predominant receptor. Inhibition of fatty acid synthesis downregulates FAO despite the presence of COL11A1, suggesting that fatty acid synthesis might be a driver of FAO in ovarian cancer cells. Taken together, our results suggest that COL11A1 upregulates fatty acid metabolism in ovarian cancer cells in a DDR2-Src-Akt-AMPK dependent manner. Therefore, we propose that blocking FAO might serve as a promising therapeutic target to treat ovarian cancer, particularly cisplatin-resistant recurrent ovarian cancers which typically express high levels of COL11A1.
Project description:Genetically engineered mouse models of lung cancer have demonstrated an important role in understanding the function of novel lung cancer oncogenes and tumor suppressor genes identified in genomic studies of human lung cancer. Further, these models are important platforms for pre-clinical therapeutic studies. Here, we generated a mouse model of lung adenocarcinoma driven by mutation of the Discoidin Domain Receptor 2 (DDR2) gene combined with loss of TP53. DDR2L63V;TP53L/L mice developed poorly differentiated lung adenocarcinomas in all transgenic animals analyzed with a latency of 40-50 weeks and a median survival of 67.5 weeks. Mice expressing wild-type DDR2 with combined TP53 loss did not form lung cancers. DDR2L63V; TP53L/L tumors displayed robust expression of DDR2 and immunohistochemical markers of lung adenocarcinoma comparable to previously generated models of lung adenocarcinoma though also displayed concomitant expression of the squamous cell markers p63 and SOX2. Tumor-derived cell lines were not solely DDR2 dependent and displayed up-regulation of and partial dependence on MYCN. Combined treatment with the BET inhibitor JQ1 and the mutltitargeted DDR2 inhibitor dasatinib inhibited tumor growth in vitro and in vivo. Together, these results suggest that DDR2 mutation can drive lung cancer initiation in vivo and provide a novel mouse model for lung cancer therapeutics studies. We used microarrays to detail the gene expression profile of mouse primary lung tumor cell lines driven by DDR2L63V;p53L/L and KrasG12D;p53L/L. When DDR2L63V; p53 and KrasG12D;p53L/L mice developed lung tumors confirmed by MRI, the mice were sacrificed and lung tumor nodules were harvested, finely minced, and cultured in 100 mm dishes with RPMI 1640/10% FBS/1% pen-strep/2mM L-Glutamine. After 3 passages, frozen stocks of these short-term cultures were prepared, and further characterized by genotyping. DDR2 expression was induced by treating cells with 2 ug/ml DOX every 2 to 3 days and confirmed by western blot analysis. The cells were cultured in RPMI 1640/10% FBS/1% pen-strep/2mM L-Glutamine. All cells were cultured at 37oC in a humidified incubator with 5% CO2.
Project description:Combined therapy with anti-BRAF plus anti-MEK is currently used as first-line treatment of patients with metastatic melanomas harboring the somatic BRAF V600E mutation. However, the main issue with targeted therapy is the acquisition of tumor cell resistance. In 70% of resistant melanoma cells, the resistant process consists in epithelial-to-mesenchymal transition (EMT). This process called phenotype switching makes melanoma cells more invasive. Its signature is characterized by MITF low, AXL high, and actin cytoskeleton reorganization through RhoA activation. In parallel of this phenotype switching phase, the resistant cells exhibit an anarchic cell proliferation due to hyper-activation of the MAP kinase pathway. We show that a majority of human melanoma overexpress discoidin domain receptor 2 (DDR2) after treatment. The same result was found in resistant cell lines presenting phenotype switching compared to the corresponding sensitive cell lines. We demonstrate that DDR2 inhibition induces a decrease in AXL expression and reduces stress fiber formation in resistant melanoma cell lines. In this phenotype switching context, we report that DDR2 control cell and tumor proliferation through the MAP kinase pathway in resistant cells in vitro and in vivo. Therefore, inhibition of DDR2 could be a new and promising strategy for countering this resistance mechanism.
Project description:Genetically engineered mouse models of lung cancer have demonstrated an important role in understanding the function of novel lung cancer oncogenes and tumor suppressor genes identified in genomic studies of human lung cancer. Further, these models are important platforms for pre-clinical therapeutic studies. Here, we generated a mouse model of lung adenocarcinoma driven by mutation of the Discoidin Domain Receptor 2 (DDR2) gene combined with loss of TP53. DDR2L63V;TP53L/L mice developed poorly differentiated lung adenocarcinomas in all transgenic animals analyzed with a latency of 40-50 weeks and a median survival of 67.5 weeks. Mice expressing wild-type DDR2 with combined TP53 loss did not form lung cancers. DDR2L63V; TP53L/L tumors displayed robust expression of DDR2 and immunohistochemical markers of lung adenocarcinoma comparable to previously generated models of lung adenocarcinoma though also displayed concomitant expression of the squamous cell markers p63 and SOX2. Tumor-derived cell lines were not solely DDR2 dependent and displayed up-regulation of and partial dependence on MYCN. Combined treatment with the BET inhibitor JQ1 and the mutltitargeted DDR2 inhibitor dasatinib inhibited tumor growth in vitro and in vivo. Together, these results suggest that DDR2 mutation can drive lung cancer initiation in vivo and provide a novel mouse model for lung cancer therapeutics studies. We used microarrays to detail the gene expression profile of mouse primary lung tumor cell lines driven by DDR2L63V;p53L/L and KrasG12D;p53L/L.
Project description:Elevation of arginase enzyme activity in the lung contributes to the pathogenesis of various chronic inflammatory diseases and infections. Inhibition of arginase expression and activity is able to alleviate those effects. Here, we investigated the immunomodulatory effect of arginase inhibitor in C. neoformans infection. In the pulmonary cryptococcosis model that was shown to recapitulate human infection, we found arginase expression was excessively induced in the lung during the late stage of infection. To inhibit the activity of arginase, we administered a specific arginase inhibitor, nor-NOHA, during C. neoformans infection. Inhibition of arginase reduced eosinophil infiltration and level of IL-13 secretion in the lungs. Whole lung transcriptome RNA-sequencing analysis revealed that treatment with nor-NOHA resulted in shifting the Th2-type gene expression patterns induced by C. neoformans infection to the Th1-type immune profile, with higher expression of cytokines Ifng, Il6, Tnfa, Csf3, chemokines Cxcl9 and Cxcl10 and transcription factor Stat1. More importantly, mice treated with arginase inhibitor had more infiltrating brain leukocytes and enhanced gene expression of Th1-associated cytokines and chemokines that are known to be essential for protection against C. neoformans infection. Inhibition of arginase dramatically attenuated spleen and brain infection, with improved survival. Taken together, these studies demonstrated that inhibiting arginase activity induced by C. neoformans infection can modulate host immune response by enhancing protective type-1 immune response during C. neoformans infection. The inhibition of arginase activity could be an immunomodulatory target to enhance protective anti-cryptococcal immune responses.