Single-cell RNA sequencing of immune cells from murine GBM tumors
Ontology highlight
ABSTRACT: We analyzed effects of IFNAR deficiency on immune cells of the GBM TME and also analyzed how anti-PD1 affected these immune cells in absence of type I IFN signaling. We also analyzed the effects of anti-PD1 treatment on the immune cell populations in absence of IFN production.
Project description:Tumors arise and grow despite anti-cancer immune responses. These responses can be stimulated by immunotherapies such as immune checkpoint inhibitors (e.g. anti-PD1 antibodies) and chimeric antigen receptors (CAR). Efficacy of these agents in solid tumors including colorectal cancers (CRC) is limited by immunosuppressive tumor microenvironment (TME) that prevents killing of malignant cells by cytotoxic T lymphocytes (CTL). Understanding the nature of TME-generated immunosuppression is of paramount importance. Here we report that TME elicited immunosuppression via eliminating activated CTL; this elimination required TME stress-induced downregulation of the IFNAR1 chain of type I interferon (IFN) receptor and attenuation of its signaling. Downregulation of IFNAR1 was observed in human colorectal cancers (CRC) and in mouse CRC models where it was required for efficient tumor development and progression. Stabilization of IFNAR1 on CTL improved their survival and increased anti- tumor activities of CAR T cells and PD1 inhibitors thereby providing a rationale for targeting IFNAR1 degradation for immunotherapies optimization. Two genotypes of mice were examined either 9 or 21 days post injection of MC38 colon cancer cells or MC38mRFP cells, respectively. 2-3 replicate mice were analyzed on separate arrays for each condition. 6 conditions in total were analyzed.
Project description:Tumors arise and grow despite anti-cancer immune responses. These responses can be stimulated by immunotherapies such as immune checkpoint inhibitors (e.g. anti-PD1 antibodies) and chimeric antigen receptors (CAR). Efficacy of these agents in solid tumors including colorectal cancers (CRC) is limited by immunosuppressive tumor microenvironment (TME) that prevents killing of malignant cells by cytotoxic T lymphocytes (CTL). Understanding the nature of TME-generated immunosuppression is of paramount importance. Here we report that TME elicited immunosuppression via eliminating activated CTL; this elimination required TME stress-induced downregulation of the IFNAR1 chain of type I interferon (IFN) receptor and attenuation of its signaling. Downregulation of IFNAR1 was observed in human colorectal cancers (CRC) and in mouse CRC models where it was required for efficient tumor development and progression. Stabilization of IFNAR1 on CTL improved their survival and increased anti- tumor activities of CAR T cells and PD1 inhibitors thereby providing a rationale for targeting IFNAR1 degradation for immunotherapies optimization.
Project description:Introduction: Immune checkpoint inhibitors(ICIs) targeting programmed cell death protein 1 (PD1) confer significant survival benefits to patients with non-small cell lung cancer (NSCLC). However, there remains a substantial unmet need to identify therapeutic approaches to overcome resistance and provide benefits to these patients. High-dose ascorbic acid (AA) acts synergistically with many standard anticancer treatments. However, little is known about the effect of high-dose AA on improving the efficacy of anti-PD1 inhibitors in NSCLC. This study aimed to elucidate the effects of high-dose AA on anti-PD1 immunotherapy in NSCLC. Methods: The combined effects of high-dose AA and anti-PD1 were investigated using a coculture model of H460 cells and CD8+ T cells and an LLC1 lung cancer syngeneic mouse model. To investigate the molecular mechanism, tumor tissues from mice were analyzed by comprehensive proteomic profiling using nano-LC-ESI-MS/MS. Results: Pretreatment with a high dose of AA led to enhanced the sensitivity to the cytotoxicity of CD8+ T cells derived from healthy donor for H460 cells. Additionally, the combination of anti-PD1 and high-dose AA significantly increased CD8+ T cell cytotoxicity in H460 cells. The combination of anti-PD1 and high-dose AA showed dramatic antitumor effects in a syngeneic mouse model of lung cancer by significantly reducing tumor growth and increasing CD8+ T cell-dependent cytotoxicity and macrophage activity. Comprehensive protein analysis confirmed that high-dose AA in anti-PD1-treated tumor tissues enhanced the antitumor effects by regulating various immune-related mechanisms, including the B cell and T cell receptor signaling pathways, Fc gamma R-mediated phagocytosis, and natural killer (NK) cell-mediated cytotoxicity. Discussion: Our results suggest that high-dose AA may be a promising adjuvant to potentiate the efficacy of anti-PD1 immunotherapy.
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:The recognition of the immune system as a key component of the tumor microenvironment (TME) led to promising therapeutics. Since such therapies benefit only subsets of patients, understanding the activities of immune cells in the TME is required. Eosinophils are an integral part of the TME especially in mucosal tumors. Nonetheless, their role in the TME and the environmental cues that direct their activities are largely unknown, especially in metastasis. We report that breast cancer-driven lung metastasis is characterized by resident and recruited eosinophils. Eosinophil recruitment to the metastatic lung was regulated by G protein coupled receptor signaling but independent of CCR3. Functionally, eosinophils promoted lymphocyte-mediated anti tumor immunity. Transcriptome and proteomic analyses identified the TME rather than intrinsic differences between eosinophil subsets as a key instructing factor directing anti tumorigenic eosinophil activities. Specifically, TNF-a/IFN-g-activated eosinophils facilitated CD4+ and CD8+ T cell infiltration and promoted anti-tumor immunity. Collectively, we identify a mechanism by which the TME entrains eosinophils to adopt anti-tumorigenic properties, which may lead to the development of eosinophil-targeted therapeutics.
Project description:<p>Although immune checkpoint blockade (CPB) leads to prolonged responses in 15-40% of patients with metastatic melanoma, treatment refractory disease and progression after initial response remain major causes of mortality. While predictors of response have been reported, the common mechanisms of both primary and acquired resistance are poorly understood. To identify mechanisms of resistance and examine the evolving landscape in response to CPB, we performed whole exome sequencing (WES), immunohistochemistry (IHC), and RNA-sequencing (RNAseq) of longitudinal tumor biopsies from 17 metastatic melanoma patients treated with various CPB therapies. We found no significant changes in both mutational and neoantigen loads over time between responders and nonresponders. However, we identified abnormalities in one gene, beta-2-microglobulin (<i>B2M</i>), an essential component of MHC Class I antigen presentation, that were present in samples during disease progression but not regression. In total, we identified <i>B2M</i> aberrations in 29.4% of patients, including multiple early frameshift mutations, loss of heterozygosity (LOH) overlapping <i>B2M</i>, and absence of tumor-specific <i>B2M</i> protein expression. Additional defects in the antigen presentation and IFNγ pathways were identified but were not restricted to progressing lesions in our cohort. In two independent cohorts of 105 and 38 melanoma patients treated with ipilimumab (anti-CTLA4) and pembrolizumab (anti-PD1) respectively, we found that <i>B2M</i> LOH was enriched 3-fold in nonresponders (~30%) vs. responders (~10%) and associated with poorer overall survival (log-rank p=0.01, p=0.006). Loss of both copies of <i>B2M</i> was found only in nonresponders. We also found evidence for association of LOH overlapping <i>IFNGR1</i> with poorer overall survival exclusively in the anti-PD1 cohort. Thus, <i>B2M</i> loss is likely a common mechanism of primary and acquired resistance to therapies targeting CTLA4 or PD-1.</p>
Project description:Most immunotherapies benefit only subsets of cancer patients, except those with autoimmune diseases due to dysregulation of their immune system. Here, the ARE-del mouse model featuring IFNg-autoimmunity allowed us to examine the relationship between cancer, autoimmunity and immunotherapy. We demonstrate that systemic levels of IFNg below 20 pg/ml in ARE-del+/- (HET) mice exerts moderate anti-tumor effects and increase (p=0.02; ANOVA) overall survival (OS); while higher levels did not that replicate in vivo the anti-tumor “bell shape” response of IFNg. Having confirmed that PD1 and CD40 are expressed in tumor-bearing ARE-del mice, anti-PD1 and anti-CD40 alone or combined were used to improve the antitumor effects of IFNg in ARE-del+/- (HET) mice. In ARE-del+/+ (WT) mice, PD1/CD40 inhibited tumor growth and improve OS because it prevented increased infiltration and trapping of tumor associated macrophages (TAMs) into necrotic areas, an event also decreased by anti-CD40 but promoted by anti-PD1. Conversely, in ARE-del+/- (HET) mice, MHC class II expressing TAM infiltration associated with severe hematological and liver adverse effects hampered the efficiency of PD1/CD40, despite significant tumor growth inhibition and strong induction of IFNg signaling. Thus, excessive activation of IFN negatively impacted immune outcome. Given the lack of consensus on the right levels of IFNg, our data show the upper limit of IFNg that define the efficacy of checkpoint inhibitors in tumor-bearing hosts with autoimmune disease.
Project description:Type I Interferons (IFN-I) are anti-viral and immuno-modulating cytokines involved in many steps across tumor initiation and progression. IFN-I act directly on tumor cells inhibiting cell growth and indirectly by activating immune cells to mount antitumor response. To understand the role of endogenous IFN-I in spontaneous, oncogene-driven carcinogenesis, we characterized tumors arising in Her2/neu transgenic (neuT) mice carrying a non-functional mutation in the IFN-I receptor (IFNAR1), thus being unresponsive to this family of cytokines. Compared to parental neu+/-mice (neuT mice), IFNAR1-/- neu+/- mice (IFNAR-neuT mice) showed earlier onset and increased tumor multiplicity with marked vascularization. Of note, IFNAR-neuT tumors specifically exhibited deregulation of genes having adverse prognostic value in breast cancer patients, including breast cancer stem cells (BCSC) marker aldehyde dehydrogenase-1A1 (ALDH1A1). An increased amount of BCSC was observed in IFNAR-neuT tumors, as assessed by ALDH1A1 enzymatic activity, clonogenic assay and tumorigenic capacity. In vitro exposure of neuT+ mammospheres and cell lines to anti-IFN-I antibodies resulted in increased frequency of ALDH+ cells, suggesting that IFN-I control stemness in tumor cells. Altogether, these results reveal an essential role of IFN-I in NeuT-driven spontaneous carcinogenesis through intrinsic control of BCSC.
Project description:We have explored at the genome-wide expression level the effects of the novel HDAC inhibitor CXD101. In human CRC cell lines, a diverse set of differentially expressed genes were up- and down-regulated. Functional profiling of the expression data highlighted immune-relevant concepts related to antigen processing and natural killer (NK) cell mediated cytotoxicity. Similar gene profiles were apparent when global gene expression was investigated in murine CT26 cells treated with CXD101, which were also apparent in syngeneic CT26 tumours growing in vivo. The ability of CXD101 to affect immune-relevant gene expression coincided with changes in the tumour micro-environment (TME), especially in the sub-groups of tumour-infiltrating lymphocytes which occurred upon CXD101 treatment. The altered TME reflected synergistic anti-tumour activity apparent when CXD101 was combined with immune oncology (IO) agents, like anti-PD1 and anti-CTLA4.The ability of CXD101 to instate antigen presentation and augment NK activity in the TME, combined with the synergy between HDAC inhibitors and IO agents, provides a powerful rationale for exploring the combination effect in human cancers.
Project description:Persistent inflammation driven by cytokines like type-one interferon (IFN-I) can cause immunosuppression. We show that administration of the JAK1 inhibitor itacitinib after anti-PD1 immunotherapy improves immune function and anti-tumor responses in mice, and results in high response rates (67%) in a phase-2 clinical trial for metastatic non-small cell lung cancer. Patients who failed to respond to initial anti-PD1 immunotherapy but responded after addition of itacitinib had multiple features of poor immune function to anti-PD1 alone that improved after JAK inhibition. Itacitinib promoted CD8 T cell plasticity and therapeutic responses of exhausted- and effector-memory-like T cell clonotypes. Patients with persistent inflammation refractory to itacitinib showed progressive CD8 T cell terminal differentiation and progressive disease. Thus, JAK inhibition may improve the efficacy of anti-PD1 immunotherapy by pivoting T cell differentiation dynamics.