ABSTRACT
CD226 has been reported to participate in the rescue of CD8+ T cell dysfunction. In this study, we aimed to assess the prognostic value of CD226 in tumor-infiltrating lymphocytes (TILs) derived from colorectal cancer (CRC) liver metastases treated with chemotherapy and radical surgery. TILs from 43 metastases were isolated and analyzed ex vivo using flow cytometry. CD155 and CD3 levels in the tumor microenvironment were assessed by immunohistochemistry. Exploration and validation of biological processes highlighted in this study were performed by bioinformatics analysis of bulk RNA-seq results for 28 CRC liver metastases pretreated with chemotherapy as well as public gene expression datasets. CD226 expression contributes to the definition of the immune context in CRC liver metastases and primary tumors. CD226 on CD8+ T cells was not specifically coexpressed with other immune checkpoints, such as PD1, TIGIT, and TIM3, in liver metastases. Multivariate Cox regression analysis revealed CD226 expression on CD8+ T cells to be an independent prognostic factor (p = 0.003), along with CD3 density at invasion margins (p = 0.003) and TIGIT expression on CD4+ T cells (p = 0.019). CD155 was not associated with the prognostic value of CD226. Gene expression analysis in a validation dataset confirmed the prognostic value of CD226 in CRC liver metastases but not in primary tumors. Downregulation of CD226 on CD8+ TILs in the liver microenvironment was restored by IL15 treatment. Overall, CD226 expression on liver metastasis-infiltrating CD8+ T cells selectively contributes to immune surveillance of CRC liver metastases and has prognostic value for patients undergoing radical surgery.
Subject(s)
Colorectal Neoplasms , Liver Neoplasms , Humans , CD8-Positive T-Lymphocytes , Colorectal Neoplasms/pathology , Liver Neoplasms/secondary , Prognosis , Receptors, Immunologic/metabolism , Tumor MicroenvironmentABSTRACT
Combining immunogenic cell death-inducing chemotherapies and PD-1 blockade can generate remarkable tumor responses. It is now well established that TGF-ß1 signaling is a major component of treatment resistance and contributes to the cancer-related immunosuppressive microenvironment. However, whether TGF-ß1 remains an obstacle to immune checkpoint inhibitor efficacy when immunotherapy is combined with chemotherapy is still to be determined. Several syngeneic murine models were used to investigate the role of TGF-ß1 neutralization on the combinations of immunogenic chemotherapy (FOLFOX: 5-fluorouracil and oxaliplatin) and anti-PD-1. Cancer-associated fibroblasts (CAF) and immune cells were isolated from CT26 and PancOH7 tumor-bearing mice treated with FOLFOX, anti-PD-1 ± anti-TGF-ß1 for bulk and single cell RNA sequencing and characterization. We showed that TGF-ß1 neutralization promotes the therapeutic efficacy of FOLFOX and anti-PD-1 combination and induces the recruitment of antigen-specific CD8+ T cells into the tumor. TGF-ß1 neutralization is required in addition to chemo-immunotherapy to promote inflammatory CAF infiltration, a chemokine production switch in CAF leading to decreased CXCL14 and increased CXCL9/10 production and subsequent antigen-specific T cell recruitment. The immune-suppressive effect of TGF-ß1 involves an epigenetic mechanism with chromatin remodeling of CXCL9 and CXCL10 promoters within CAF DNA in a G9a and EZH2-dependent fashion. Our results strengthen the role of TGF-ß1 in the organization of a tumor microenvironment enriched in myofibroblasts where chromatin remodeling prevents CXCL9/10 production and limits the efficacy of chemo-immunotherapy.
Subject(s)
Cancer-Associated Fibroblasts , Neoplasms , Mice , Animals , Cancer-Associated Fibroblasts/pathology , CD8-Positive T-Lymphocytes , Immunotherapy/methods , Chemokines/therapeutic use , Neoplasms/drug therapy , Tumor MicroenvironmentABSTRACT
Evidences highlight the role of various CD4+ helper T cells (CD4+ Th) subpopulations in orchestrating the immune responses against cancers. Epigenetics takes an important part in the regulation of CD4+ Th polarization and plasticity. In this review, we described the epigenetic factors that govern CD4+ T cells differentiation and recruitment in the tumor microenvironment and their subsequent involvement in the antitumor immunity. Finally, we discussed how to manipulate tumor reactive CD4+ Th responses by epigenetic drugs to improve anticancer immunotherapy.
Subject(s)
Antineoplastic Agents/therapeutic use , Cellular Reprogramming/drug effects , Epigenesis, Genetic/drug effects , Immunotherapy, Adoptive , Lymphocytes, Tumor-Infiltrating/drug effects , Neoplasms/therapy , T-Lymphocytes, Helper-Inducer/drug effects , T-Lymphocytes, Helper-Inducer/transplantation , Animals , Antineoplastic Agents/adverse effects , Cell Differentiation/drug effects , Humans , Immunotherapy, Adoptive/adverse effects , Lymphocytes, Tumor-Infiltrating/immunology , Lymphocytes, Tumor-Infiltrating/metabolism , Neoplasms/genetics , Neoplasms/immunology , Neoplasms/metabolism , T-Lymphocytes, Helper-Inducer/immunology , T-Lymphocytes, Helper-Inducer/metabolism , Treatment Outcome , Tumor MicroenvironmentABSTRACT
Androgen deprivation therapy (ADT) is the standard of care for treatment of nonresectable prostate cancer. Despite high treatment efficiency, most patients ultimately develop lethal castration-resistant prostate cancer (CRPC). In this study, we performed a comparative proteomic analysis of three in vivo, androgen receptor (AR)-responsive orthograft models of matched hormone-naïve prostate cancer and CRPC. Differential proteomic analysis revealed that distinct molecular mechanisms, including amino acid (AA) and fatty acid metabolism, are involved in the response to ADT in the different models. Despite this heterogeneity, Schlafen family member 5 (SLFN5) was identified as an AR-regulated protein in CRPC. SLFN5 expression was high in CRPC tumors and correlated with poor patient outcome. In vivo, SLFN5 depletion strongly impaired tumor growth in castrated conditions. Mechanistically, SLFN5 interacted with ATF4 and regulated the expression of LAT1, an essential AA transporter. Consequently, SLFN5 depletion in CRPC cells decreased intracellular levels of essential AA and impaired mTORC1 signaling in a LAT1-dependent manner. These results confirm that these orthograft models recapitulate the high degree of heterogeneity observed in patients with CRPC and further highlight SLFN5 as a clinically relevant target for CRPC. SIGNIFICANCE: This study identifies SLFN5 as a novel regulator of the LAT1 amino acid transporter and an essential contributor to mTORC1 activity in castration-resistant prostate cancer.
Subject(s)
Biomarkers, Tumor/metabolism , Cell Cycle Proteins/metabolism , Gene Expression Regulation, Neoplastic , Large Neutral Amino Acid-Transporter 1/metabolism , Prostatic Neoplasms, Castration-Resistant/pathology , TOR Serine-Threonine Kinases/metabolism , Activating Transcription Factor 4/genetics , Activating Transcription Factor 4/metabolism , Animals , Apoptosis , Biomarkers, Tumor/genetics , Cell Cycle Proteins/genetics , Cell Proliferation , Humans , Large Neutral Amino Acid-Transporter 1/genetics , Male , Mechanistic Target of Rapamycin Complex 1/genetics , Mechanistic Target of Rapamycin Complex 1/metabolism , Metabolome , Mice , Mice, Nude , Prognosis , Prostatic Neoplasms, Castration-Resistant/genetics , Prostatic Neoplasms, Castration-Resistant/metabolism , Proteome , Survival Rate , TOR Serine-Threonine Kinases/genetics , Transcriptome , Tumor Cells, Cultured , Xenograft Model Antitumor AssaysABSTRACT
BACKGROUND: The positive role of CD8+ tumor-infiltrating lymphocytes (TIL) in patients with colorectal cancer (CRC) has been well described but the prognostic value of CD4 T cell subsets remained to be investigated. In this study, we expanded TIL from surgically resected liver metastases of patients with CRC and characterized the phenotype and the prognostic value of expanded-CD4 T cells. METHODS: Liver metastases were surgically resected from 23 patients with CRC. Tumors were enzymatically digested and cultured in high dose of interleukin-2 for up to 5 weeks. T cell phenotype and reactivity of cultured-T cells were measured by flow cytometry and correlated with patients' clinical outcomes. RESULTS: We successfully expanded 21 over 23 TIL from liver metastases of patients with CRC. Interestingly, we distinguished two subsets of expanded T cells based on T cell immunoglobulin mucin domain-containing protein 3 (TIM-3) expression. Medians fold expansion of expanded T cells after rapid expansion protocol was higher in CD3+TIM-3low cultures. In an attempt to investigate the correlation between the phenotype of expanded CD4 T cells and clinical outcomes, we observed on one hand that the level of Tregs in culture as well as the expression of both PD1 and TIM-3 by expanded T cells was not correlated to the clinical outcomes. Interestingly, on the other hand, cultures containing high levels of Th17 cells were associated with a poor prognosis (p=0.0007). CONCLUSIONS: Our data confirmed the presence of Th17 cells in expanded T cells from liver metastases. Among CD4 T cell characteristics investigated, TIM-3 but not programmed cell death protein 1 predicted the expansion capacity of TIL while only the Th17 phenotype showed correlation with patients' survival, suggesting a particular role of this T cell subset in CRC immune contexture. TRIAL REGISTRATION NUMBER: NCT02817178.
Subject(s)
CD4-Positive T-Lymphocytes/immunology , Colorectal Neoplasms/complications , Colorectal Neoplasms/immunology , Liver Neoplasms/secondary , T-Lymphocyte Subsets/immunology , Aged , Aged, 80 and over , Female , Humans , Lymphocytes, Tumor-Infiltrating , Male , Middle Aged , PrognosisABSTRACT
Th17 cells represent a subset of CD4+ T cells characterized by the master transcription factor RORγt and the production of IL-17. Epigenetic modifications such as post-translational histone modifications and DNA methylation play a key role in Th17 cell differentiation and high plasticity. Th17 cells are highly recruited in many types of cancer and can be associated with good or bad prognosis. Here, we will review the remodeling of the epigenome induced by the tumor microenvironment, which may explain Th17 cell predominance. We will also discuss the promising treatment perspectives of molecules targeting epigenetic enzymes to remodel a Th17-enriched tumor microenvironment.
