Project description:Glioblastoma is an aggressive brain malignancy with a dismal prognosis. With emerging evidence that disproves the immune privileged environment in the brain, there is much interest in examining various immunotherapy strategies to treat these incurable cancers. Unfortunately, to date, clinical studies investigating immunotherapy regimens have not provided much evidence of efficacy, leading to questions about the suitability of immunotherapy strategies for these tumors. Inadequate inherent populations of lymphocytes in tumor (TILs) and limited trafficking of systemic circulating T cells into the central nervous system (CNS) likely contribute to the poor response to immunotherapy treatment for primary CNS cancers. This paucity of TILs is in concert with the finding of epigenetic silencing of genes that promote immune cell movement (chemotaxis) to the tumor. In this study we evaluated the ability of GSK126, a blood-brain barrier permeable small molecule inhibitor of EZH2, to reverse the epigenetic silencing of chemokines like CXCL9 and CXCL10. When combined with anti-PD-1 treatment, these IFN driven chemokines promote T cell infiltration, resulting in decreased tumor growth and enhanced survival in immunocompetent murine sub-cutaneous and intracranial tumor syngeneic models of GBM. Examination of the tumor micro-environment revealed that the decrease in tumor growth in the mice treated with the drug combination was accompanied by increased tumor CD8 T cell infiltration along with higher IFN expression. Additionally, a significant increase in CXCR3+ T cells in the draining lymph nodes was also found. Taken together, our data suggests that in glioblastoma, epigenetic modulation using GSK126 could improve current immunotherapy strategies by reversing the epigenetic changes that enable immune cell evasion leading to enhanced immune cell trafficking to the tumor.
Project description:Cancers evade the immune system in order to grow or metastasise through the process of cancer immunoediting. While checkpoint inhibitor therapy has been effective for reactivating tumour immunity in some cancers, many solid cancers, including breast cancer, remain largely non-responsive. Understanding the way non-responsive cancers evolve to evade immunity, what resistance pathways are activated and whether this occurs at the clonal level will improve immunotherapeutic design. We tracked cancer cell clones during the immunoediting process and determined clonal transcriptional profiles that allow immune evasion in murine mammary tumour growth in response to immunotherapy with anti-PD1 and anti-CTLA4. Clonal diversity was significantly restricted by immunotherapy treatment at both the primary and metastatic sites. These findings demonstrate that immunoediting selects for pre-existing breast cancer cell populations, that immunoediting is not a static process and is ongoing during metastasis and immunotherapy treatment. Isolation of immunotherapy resistant clones revealed unique and overlapping transcriptional signatures. The overlapping gene signature was predictive of poor survival in basal-like breast cancer patient cohorts. Some of these overlapping genes have existing small molecules which can be used to potentially improve immunotherapy response.
Project description:Tumor-induced immunosuppression remains a major challenge for immunotherapy of cancer patients. To further elucidate why an allogeneic gene-modified (Interleukin-7(IL-7)/CD80 co-transfected) renal cell cancer vaccine failed to induce clinically relevant TH1-polarized immune responses, peripheral blood mononuclear cells (PBMCs) from enrolled study patients were analyzed by gene expression profiling (GEP) both prior and after vaccination. At baseline before vaccination, a profound downregulation of gene signatures associated with antigen presentation, immune response/T cells, cytokines/chemokines and signaling/transcription factors was observed in renal cell cancer patients as compared to healthy controls. Vaccination led to a partial reversion of preexisting immunosuppression, however, GEP indicated that an appropriate TH1 polarization could not be achieved. Most interestingly, our results suggest that the nuclear factor kappa B (NF-M-NM-:B) signaling pathway might be involved in the impairment of immunological responsiveness and the observed TH2 deviation. In summary, our data suggest that GEP might be a powerful tool for the prediction of immunosuppression and the monitoring of immune responses within immunotherapy trials. Gene expression was profiled using Affymetrix Human Gene v1.1 ST microarrays in the following settings: 9 RCC patients were profiled before and after vaccination (pairs of measurements) and additionally 9 healthy control samples were profiled.
Project description:Tumor metabolic reprogramming has been recognized as a critical determinant in tumor development and cancer immunotherapy. Aberrant choline metabolism is emerging as a defining hallmark of cancer. However, its impact on antitumor immunity remains largely unclear. Carbohydrate responsive element binding protein (ChREBP)-mediated choline deprivation impels tumor-associated macrophages (TAMs) reprogramming and maintains an immunosuppressive tumor microenvironment (TME). Mechanistically, ChREBP interacts with SP1 to increase the expression of immunosuppressive chemokines CCL2 and CXCL1, as well as choline transporter SLC44A1. As such, high expression of CCL2 and CXCL1 expression promotes recruitment of TAMs and MDSCs in the TME. Tumor cells with high SLC44A1 expression compete consuming choline with M1-like TAMs, inhibiting cGAS-STING signaling and promoting the polarization of M1 to M2 macrophages. Clinically, ChREBP-SP1-choline metabolism axis expression is associated with poor clinical outcome in CRC. Inhibiting ChREBP reduces M2-like TAMs and MDSCs to enhance anti-tumor immunity, suggesting ChREBP as a potential immunotherapy target in cancer.
Project description:Overcoming immunosuppression in tumor microenvironment (TME) is fundamental to the development of novel cancer immunotherapies. Herein, we revealed an unrecognized role of IL-16 in shaping anti-tumor immunity. Compared with healthy subjects, cancer patients had impaired production of IL-16, which was correlated with inferior patient prognosis. In multiple murine cancer models, IL-16 administration augmented the anti-tumor immune responses and thus restrained tumor growth. Mechanistically, IL-16 potentiated the polarization of T helper 1 (Th1) cells and the production of their effector cytokine IFN-γ, Mechanistically, IL-16 blocked glutamine catabolism by downregulating glutaminase (GLS) expression in CD4+ T cells. The IL-16-established Th1 tumor microenvironment further increased the expression of CXCR3 ligands in tumor-associated macrophages, which improved the therapeutic efficacy of immune checkpoint blockade (ICB). In cancer patients who received anti-PD1 therapy, high IL-16 levels correlated with better responsiveness. Finally, we found that the impaired production of histamine by mast cells was a causative factor for IL-16 downregulation in TME. Thus, IL-16 administration may serve as a potential approach to augment anti-tumor immunity, and also improve the outcome of ICB therapy in cancer patients. Collectively, we provided new insights into the biological function of IL-16 and thus highlighted its potential clinical value in cancer immunotherapy.
Project description:Overcoming immunosuppression in tumor microenvironment (TME) is crucial for the development of novel cancer immunotherapies. In this study, we revealed a previously unrecognized role of IL-16 in shaping anti-tumor immunity. Compared to healthy individuals, cancer patients exhibited impaired production of IL-16, which was associated with inferior patient prognosis. In multiple murine cancer models, IL-16 administration augmented the anti-tumor immune responses and thus restrained tumor growth. Further investigation uncovered that IL-16 potentiated the polarization of T helper 1 (Th1) cells and the production of their effector cytokine IFN-γ. Mechanistically, IL-16 inhibited glutamine catabolism by downregulating the expression of glutaminase (GLS) in CD4+ T cells. The establishment of IL-16-dependent Th1 tumor microenvironment further increased the expression of CXCR3 ligands in tumor-associated macrophages (TAMs), thereby improving the therapeutic effectiveness of immune checkpoint blockade (ICB). In cancer patients who received anti-PD1 therapy, higher levels of IL-16 were correlated with better responsiveness. Finally, we found that the impaired production of histamine by mast cells was a contributing factor to the downregulation of IL-16 in TME. Therefore, IL-16 could potentially be utilized as a therapeutic approach to augment anti-tumor immunity, and improve the outcome of ICB therapy in cancer patients. Collectively, our research provided new insights into the biological function of IL-16, emphasizing its potential clinical significance in cancer immunotherapy.
Project description:scRNAseq-based unsupervised clustering and clonotyping revealed that Th1/17 and CCR6 SP clusters formed metacluster Th7R, which was distinct from Th1 or Th17, characterized by high expression of the IL-7 receptor. Use of this cluster to assess antitumor CD4+ T cell immunity from the peripheral blood and to predict the efficacy of immune checkpoint inhibitors will pave the way for novel antitumor immunotherapy strategies for patients.
Project description:Analysis of the effect of cyclophosphamide on peripheral blood leukocyte gene expression. Certain chemotherapeutic drugs such as cyclophosphamide can enhance the antitumor efficacy of immunotherapy because of their capacity to modulate innate and adaptive immunity. Indeed, it has been argued that this capacity may be more significant to chemotherapeutic efficacy in general than is presently appreciated. To gain insights into the core mechanisms of chemoimmunotherapy, we methodically profiled the effects of cyclophosphamide on gene expression in bone marrow, spleen and peripheral blood, and on cytokine expression in plasma and bone marrow of tumor-bearing mice. Gene and protein expression were modulated early and transiently by cyclophosphamide, leading to upregulation of a variety of immunomodulatory factors, including danger signals, pattern recognition receptors, inflammatory mediators, growth factors, cytokines, chemokines and chemokine receptors. These factors are involved in sensing cyclophosphamide myelotoxicity and activating repair mechanisms, which, in turn, stimulate immunoactivation events that promote efficacy. In particular, cyclophosphamide induced a T helper 17 (Th17)-related gene signature associated with an increase in Th17, Th1 and activated CD25+CD4+Foxp3- T lymphocytes and a slight recovery of regulatory T-cells. By analyzing gene and protein expression kinetics and their relationship to the antitumor efficacy of different therapeutic schedules of combination, we determined that optimal timing for performing adoptive immunotherapy is approximately 1 day after cyclophosphamide treatment. Together, our findings highlight factors that may propel the efficacy of chemoimmunotherapy, offering a mechanistic glimpse of the important immune modulatory effects of cyclophosphamide Four-condition experiment, Untreated mice - Cyclophosphamide-treated mice 1 day - Cyclophosphamide-treated mice 2 days - Cyclophosphamide-treated mice 5 days. Biological replicates: 4, controls: 4, independently harvested. Two replicates per array.