Project description:BACKGROUND: CXCR1/2 inhibitors are being implemented with immunotherapies in PDAC clinical trials. CXCL ligands are a family of cytokines responsible for stimulating these receptors; while typically secreted by activated immune cells, fibroblasts, and even adipocytes, they are also secreted by immune-evasive cancer cells. CXCL ligand release is known to occur in response to inflammatory stimuli, whether pathogenic (bacterial) or endogenous (obesity). Obesity has been linked to poor patient outcome and altered anti-tumor immunity in pancreatic cancer. Importantly, adipose-derived cytokines and chemokines have been implicated as potential drivers of tumor cell immune evasion; cumulatively these findings suggest that targeting CXC ligands may be beneficial in the context of obesity. METHODS: RNA-sequencing of human PDAC cell lines was used to assess differential influences of adipose conditioned media on the cancer cell transcriptome. In addition, the adipose-induced secretome of PDAC cells was validated with ELISA for induced CXCL5 secretion. Human tissue data from CPTAC was used to correlate IL-1β and TNF expression with both CXCL5 mRNA and protein levels. CRISPR-Cas9 was used to knock out CXCL5 from a murine PDAC cell line in order to assess orthotopic tumor studies in syngeneic, diet-induced obese mice. Flow cytometry was used to compare the immune profiles between tumors. Mice were monitored for differences in tumor size at endpoint in combination with Anti-PD-1 immune checkpoint blockade therapy. RESULTS: Human adipose conditioned media (hAT-CM) stimulates CXCL5 secretion from PDAC cells via either IL-1β or TNF; neutralization of both is required to significantly block release of CXCL5 from tumor cells. Ablation of CXCL5 from tumors promoted an enriched immune phenotype with an unanticipatedly increased number of exhausted CD8 T cells. Application of anti-PD-1 treatment to control tumors failed to alter tumor growth, yet treatment of CXCL5 deficient tumors showed response by significantly diminished tumor mass. CONCLUSIONS: In summary, our findings show that both TNF and IL-1β can stimulate CXCL5 release from PDAC cells in vitro, which correlates with expression in patient data. CXCL5 depletion in vivo alone is sufficient to promote T cell infiltration into tumors, increasing efficacy of checkpoint blockade inhibition and alleviating tumor burden.
Project description:The CD155/TIGIT axis can be co-opted during immune evasion in chronic viral infections and cancer. Pancreatic adenocarcinoma (PDAC) is a highly lethal malignancy, and immune-based strategies to combat this disease have been largely unsuccessful to date. We corroborate prior reports that a substantial portion of PDAC harbors predicted high affinity MHC class I-restricted neoepitopes and extend these findings to advanced/metastatic disease. Using two novel preclinical models of neoantigen-expressing PDAC, we demonstrate that intratumoral neoantigen-specific CD8+ T cells adopt multiple states of dysfunction, which are similar to tumor-infiltrating lymphocytes of human PDAC patients. Mechanistically, genetic and/or pharmacologic modulation of the CD155/TIGIT axis was sufficient to promote immune evasion in autochthonous neoantigen-expressing PDAC. Finally, we demonstrate that the CD155/TIGIT axis is critical to maintain immune evasion in PDAC and uncover a combination immunotherapy (TIGIT/PD-1 co-blockade plus CD40 agonism) that elicits profound anti-tumor responses in preclinical models, now poised for clinical evaluation.
Project description:Purpose: The goal of this study was to identify BET-dependent pathways in the PDAC stroma and the epithelial compartment. Methods: Monocultures and Cocultures of a low passage PDAC cell line (MGH1319) and a cancer-associated fibroblast cell line (CAF-1) were treated with either BETi (CPI203) or CTRL for 24 hours. Each condition was done as a single experiment and all cells were subjected to FACS, RNA was isolated using the RNeasy Micro Kit (CAT No.74004) and sequenced at 75 bp Pair End on the NextSeq sequencer (Illumina). qRT–PCR validation was performed using TaqMan assays. Results: In vitro co-cultures of PDAC and CAF cells demonstrated that matrisome expression was regulated by BET-dependent PDAC-CAF crosstalk. Conclusions: PDAC matrisome expression is dependent on tumor-stroma crosstalk and regulated in parts by BET proteins.
Project description:Pancreatic ductal adenocarcinoma (PDAC) is a highly metastatic and lethal disease. Gasdermins are primarily associated with necrosis via membrane permeabilization and pyroptosis, a lytic pro-inflammatory type of cell death. In this study, we report GSDMC upregulation during PDAC progression. GSDMC directly induces genes related to stemness, EMT, and immune evasion. Targeting Gsdmc in murine PDAC models reprograms the immunosupressive tumor microenvironment, resulting in diminished tumor initiation, growth, metastasis, and enhanced response to PD-1 checkpoint inhibition. Mechanistically, we discover that ADAM17 cleaves GSDMC, releasing a C-terminal fragment that translocates to the nucleus and binds to promoter regions of stemness, metastasis, and immune evasion-related genes. Pharmacological inhibition of GSDMC cleavage or hindrance of its nuclear translocation was equally effective in suppressing downstream targets and inhibiting PDAC progression. Our findings position GSDMC as a potential therapeutic target for enhancing treatment response in this deadly disease.
Project description:CXCL5, a strong neutrophil-chemoattractant, has been reportet to be expressed in different cancer entities with diverse outcomes in disease progression. Contradictory outcome in disease progression in different tumor entities might be explained by a tumor type specific expression pattern of chemokines, chemokine receptors and growth factors that act in concert with CXCL5. This study evaluates the impact of CXCL5 expression on the tumor mircoenvironment in a syngeneic mouse melanoma model.
Project description:Pancreatic ductal adenocarcinoma (PDAC) is one of the deadliest malignancies and is known for its high resistance and low response to treatment. Tumor immune evasion is a major stumbling block in designing effective anticancer therapeutic strategies. Karyopherin alpha 2 (KPNA2), a member of the nuclear transporter family, is elevated in multiple human cancers and accelerates carcinogenesis. However, the specific role of KPNA2 in PDAC remains unclear. In this study, we found that expression of KPNA2 was significantly upregulated in PDAC compared to adjacent nontumor tissue and its high expression was correlated with poor survival outcome by analyzing the GEO datasets. Similar KPNA2 expression pattern was also found in both human patient samples and KPC mouse models through IHC staining. Although KPNA2 knockdown failed to impair the vitality and migration ability of PDAC cells in vitro, the in vivo tumor growth was significantly impeded and the expression of immune checkpoint ligand PD-L1 was reduced by silencing KPNA2. Furthermore, we uncovered that KPNA2 modulated the expression of PD-L1 by mediating nuclear translocation of STAT3. Collectively, our data suggested that KPNA2 has the potential to serve as a promising biomarker for diagnosis in PDAC.
Project description:Pancreatic ductal adenocarcinoma (PDAC) is one of the deadliest malignancies and is known for its high resistance and low response to treatment. Tumor immune evasion is a major stumbling block in designing effective anticancer therapeutic strategies. Karyopherin alpha 2 (KPNA2), a member of the nuclear transporter family, is elevated in multiple human cancers and accelerates carcinogenesis. However, the specific role of KPNA2 in PDAC remains unclear. In this study, we found that expression of KPNA2 was significantly upregulated in PDAC compared to adjacent nontumor tissue and its high expression was correlated with poor survival outcome by analyzing the GEO datasets. Similar KPNA2 expression pattern was also found in both human patient samples and KPC mouse models through IHC staining. Although KPNA2 knockdown failed to impair the vitality and migration ability of PDAC cells in vitro, the in vivo tumor growth was significantly impeded and the expression of immune checkpoint ligand PD-L1 was reduced by silencing KPNA2. Furthermore, we uncovered that KPNA2 modulated the expression of PD-L1 by mediating nuclear translocation of STAT3. Collectively, our data suggested that KPNA2 has the potential to serve as a promising biomarker for diagnosis in PDAC.