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Gut Aug 2023The role of N-methyladenosine (mA) in tumour immune microenvironment (TIME) remains understudied. Here, we elucidate function and mechanism of YTH N-methyladenosine RNA...
OBJECTIVE
The role of N-methyladenosine (mA) in tumour immune microenvironment (TIME) remains understudied. Here, we elucidate function and mechanism of YTH N-methyladenosine RNA binding protein 1 (YTHDF1) in colorectal cancer (CRC) TIME.
DESIGN
Clinical significance of YTHDF1 was assessed in tissue microarrays (N=408) and TCGA (N=526) cohorts. function was determined in syngeneic tumours, intestine-specific knockin mice, and humanised mice. Single-cell RNA-seq (scRNA-seq) was employed to profile TIME. Methylated RNA immunoprecipitation sequencing (MeRIP-seq), RNA sequencing (RNA-seq) and ribosome sequencing (Ribo-seq) were used to identify YTHDF1 direct targets. Vesicle-like nanoparticles (VNPs)-encapsulated -siRNA was used for silencing in vivo.
RESULTS
expression negatively correlated with interferon-γ gene signature in TCGA-CRC. Concordantly, YTHDF1 protein negatively correlated with CD8 T-cell infiltration in independent tissue microarrays cohorts, implying its role in TIME. Genetic depletion of augmented antitumour immunity in CT26 (MSS-CRC) and MC38 (MSI-H-CRC) syngeneic tumours, while knockin promoted an immunosuppressive TIME facilitating CRC in azoxymethane-dextran sulphate-sodium or models. scRNA-seq identified reduction of myeloid-derived suppressor cells (MDSCs), concomitant with increased cytotoxic T cells in knockout tumours. Integrated MeRIP-seq, RNA-seq and Ribo-seq revealed p65/Rela as a YTHDF1 target. YTHDF1 promoted p65 translation to upregulate CXCL1, which increased MDSC migration via CXCL1-CXCR2 axis. Increased MSDCs in turn antagonised functional CD8 T cells in TIME. Importantly, targeting YTHDF1 by CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) or VNPs-si boosted anti-PD1 efficacy in MSI-H CRC, and overcame anti-PD1 resistance in MSS CRC.
CONCLUSION
YTHDF1 impairs antitumour immunity via an mA-p65-CXCL1/CXCR2 axis to promote CRC and serves as a therapeutic target in immune checkpoint blockade therapy.
Topics: Mice; Animals; CD8-Positive T-Lymphocytes; Colonic Neoplasms; Colorectal Neoplasms; Tumor Microenvironment
PubMed: 36717220
DOI: 10.1136/gutjnl-2022-328845 -
Frontiers in Immunology 2022In recent years, there has been an emphasis on harnessing the immune system for therapeutic interventions. Adoptive cell therapies (ACT) have emerged as an effective... (Review)
Review
In recent years, there has been an emphasis on harnessing the immune system for therapeutic interventions. Adoptive cell therapies (ACT) have emerged as an effective option for B-cell derived hematological malignancies. Despite remarkable successes with ACT, immune dysregulation and the leukemia microenvironment can critically alter clinical responses. Therefore, preclinical modeling can contribute to the advancement of ACT for leukemias. Human xenografts, the current mainstay of ACT models, cannot evaluate the impact of the immunosuppressive leukemia microenvironment on adoptively transferred cells. Syngeneic mouse models utilize murine tumor models and implant them into immunocompetent mice. This provides an alternative model, reducing the need for complicated breeding strategies while maintaining a matched immune system, stromal compartment, and leukemia burden. Syngeneic models that evaluate ACT have analyzed the complexity of cytotoxic T lymphocytes, T cell receptor transgenics, and chimeric antigen receptors. This review examines the immunosuppressive features of the leukemia microenvironment, discusses how preclinical modeling helps predict ACT associated toxicities and dysfunction, and explores publications that have employed syngeneic modeling in ACT studies for the improvement of therapy for leukemias.
Topics: Animals; Humans; Immunosuppressive Agents; Immunotherapy, Adoptive; Leukemia; Mice; Receptors, Chimeric Antigen; T-Lymphocytes, Cytotoxic; Tumor Microenvironment
PubMed: 35401520
DOI: 10.3389/fimmu.2022.867103 -
BMC Cancer Nov 2021Immune checkpoint blockade (ICB) therapies have changed the paradigm of cancer therapies. However, anti-tumor response of the ICB is insufficient for many patients and...
BACKGROUND
Immune checkpoint blockade (ICB) therapies have changed the paradigm of cancer therapies. However, anti-tumor response of the ICB is insufficient for many patients and limited to specific tumor types. Despite many preclinical and clinical studies to understand the mechanism of anti-tumor efficacy of ICB, the mechanism is not completely understood. Harnessing preclinical tumor models is one way to understand the mechanism of treatment response.
METHODS
In order to delineate the mechanisms of anti-tumor activity of ICB in preclinical syngeneic tumor models, we selected two syngeneic murine colorectal cancer models based on in vivo screening for sensitivity with anti-PD-1 therapy. We performed tumor-immune profiling of the two models to identify the potential mechanism for anti-PD-1 response.
RESULTS
We performed in vivo screening for anti-PD-1 therapy across 23 syngeneic tumor models and found that CT-26 and Colon 26, which are murine colorectal carcinoma derived from BALB/c mice, showed different sensitivity to anti-PD-1. CT-26 tumor mice were more sensitive to the anti-PD-1 antibody than Colon 26, while both models show similarly sensitivity to anti-CTLA4 antibody. Immune-profiling showed that CT-26 tumor tissue was infiltrated with more immune cells than Colon 26. Genomic/transcriptomic analyses highlighted thatWnt pathway was one of the potential differences between CT-26 and Colon 26, showing Wnt activity was higher in Colon 26 than CT-26. .
CONCLUSIONS
CT-26 and Colon 26 syngeneic tumor models showed different sensitivity to anti-PD-1 therapy, although both tumor cells are murine colorectal carcinoma cell lines from BALB/c strain. By characterizing the mouse cells lines and tumor-immune context in the tumor tissues with comprehensive analysis approaches, we found that CT-26 showed "hot tumor" profile with more infiltrated immune cells than Colon 26. Further pathway analyses enable us to propose a hypothesis that Wnt pathway could be one of the major factors to differentiate CT-26 from Colon 26 model and link to anti-PD-1 response. Our approach to focus on preclinical tumor models with similar genetic background but different sensitivity to anti-PD-1 therapy would contribute to illustrating the potential mechanism of anti-PD-1 response and to generating a novel concept to synergize current anti-PD-1 therapies for cancer patients.
Topics: Animals; Base Sequence; Cell Line, Tumor; Colonic Neoplasms; Disease Models, Animal; Female; Gene Expression Profiling; Immune Checkpoint Inhibitors; Mice; Mice, Inbred BALB C; Mice, Inbred C57BL; Mice, Inbred DBA; Neoplasm Transplantation; Transcriptome; Exome Sequencing; Wnt Signaling Pathway
PubMed: 34774008
DOI: 10.1186/s12885-021-08974-3 -
Cancer Research Aug 2022Immune-checkpoint blockade (ICB) promotes antitumor immune responses and can result in durable patient benefit. However, response rates in breast cancer patients remain...
UNLABELLED
Immune-checkpoint blockade (ICB) promotes antitumor immune responses and can result in durable patient benefit. However, response rates in breast cancer patients remain modest, stimulating efforts to discover novel treatment options. Cancer-associated fibroblasts (CAF) represent a major component of the breast tumor microenvironment and have known immunosuppressive functions in addition to their well-established roles in directly promoting tumor growth and metastasis. Here we utilized paired syngeneic mouse mammary carcinoma models to show that CAF abundance is associated with insensitivity to combination αCTLA4 and αPD-L1 ICB. CAF-rich tumors exhibited an immunologically cold tumor microenvironment, with transcriptomic, flow cytometric, and quantitative histopathologic analyses demonstrating a relationship between CAF density and a CD8+ T-cell-excluded tumor phenotype. The CAF receptor Endo180 (Mrc2) is predominantly expressed on myofibroblastic CAFs, and its genetic deletion depleted a subset of αSMA-expressing CAFs and impaired tumor progression in vivo. The addition of wild-type, but not Endo180-deficient, CAFs in coimplantation studies restricted CD8+ T-cell intratumoral infiltration, and tumors in Endo180 knockout mice exhibited increased CD8+ T-cell infiltration and enhanced sensitivity to ICB compared with tumors in wild-type mice. Clinically, in a trial of melanoma patients, high MRC2 mRNA levels in tumors were associated with a poor response to αPD-1 therapy, highlighting the potential benefits of therapeutically targeting a specific CAF subpopulation in breast and other CAF-rich cancers to improve clinical responses to immunotherapy.
SIGNIFICANCE
Paired syngeneic models help unravel the interplay between CAF and tumor immune evasion, highlighting the benefits of targeting fibroblast subpopulations to improve clinical responses to immunotherapy.
Topics: Animals; CD8-Positive T-Lymphocytes; Cancer-Associated Fibroblasts; Cell Line, Tumor; Immune Checkpoint Inhibitors; Mice; Neoplasms; Tumor Microenvironment
PubMed: 35749591
DOI: 10.1158/0008-5472.CAN-21-4141 -
Science Translational Medicine Feb 2020Checkpoint inhibitors have revolutionized cancer therapy but only work in a subset of patients and can lead to a multitude of toxicities, suggesting the need for more...
Checkpoint inhibitors have revolutionized cancer therapy but only work in a subset of patients and can lead to a multitude of toxicities, suggesting the need for more targeted delivery systems. Because of their preferential colonization of tumors, microbes are a natural platform for the local delivery of cancer therapeutics. Here, we engineer a probiotic bacteria system for the controlled production and intratumoral release of nanobodies targeting programmed cell death-ligand 1 (PD-L1) and cytotoxic T lymphocyte-associated protein-4 (CTLA-4) using a stabilized lysing release mechanism. We used computational modeling coupled with experimental validation of lysis circuit dynamics to determine the optimal genetic circuit parameters for maximal therapeutic efficacy. A single injection of this engineered system demonstrated an enhanced therapeutic response compared to analogous clinically relevant antibodies, resulting in tumor regression in syngeneic mouse models. Supporting the potentiation of a systemic immune response, we observed a relative increase in activated T cells, an abscopal effect, and corresponding increases in systemic T cell memory populations in mice treated with probiotically delivered checkpoint inhibitors. Last, we leveraged the modularity of our platform to achieve enhanced therapeutic efficacy in a poorly immunogenic syngeneic mouse model through effective combinations with a probiotically produced cytokine, granulocyte-macrophage colony-stimulating factor (GM-CSF). Together, these results demonstrate that our engineered probiotic system bridges synthetic biology and immunology to improve upon checkpoint blockade delivery.
Topics: Animals; CTLA-4 Antigen; Disease Models, Animal; Humans; Immunotherapy; Mice; Neoplasms; Probiotics; Single-Domain Antibodies; T-Lymphocytes
PubMed: 32051224
DOI: 10.1126/scitranslmed.aax0876 -
Hepatology (Baltimore, Md.) May 2023The treatment of hepatocellular carcinoma (HCC) has been transformed by the use of immune checkpoint inhibitors. However, most patients with HCC do not benefit from...
BACKGROUND AND AIMS
The treatment of hepatocellular carcinoma (HCC) has been transformed by the use of immune checkpoint inhibitors. However, most patients with HCC do not benefit from treatment with immunotherapy. There is an urgent need to understand the mechanisms that underlie response or resistance to immunotherapy for patients with HCC. The use of syngeneic mouse models that closely recapitulate the heterogeneity of human HCC will provide opportunities to examine the complex interactions between cancer cells and nonmalignant cells in the tumor microenvironment.
APPROACH AND RESULTS
We leverage a multifaceted approach that includes imaging mass cytometry and suspension cytometry by time of flight to profile the tumor microenvironments of the Hep53.4, Hepa 1-6, RIL-175, and TIBx (derivative of TIB-75) syngeneic mouse HCC models. The immune tumor microenvironments vary across these four models, and various immunosuppressive pathways exist at baseline in orthotopic liver tumors derived from these models. For instance, TIBx, which is resistant to anti-programmed cell death protein 1 therapy, contains a high proportion of "M2-like" tumor-associated macrophages with the potential to diminish antitumor immunity. Investigation of The Cancer Genome Atlas reveals that the baseline immunologic profiles of Hep53.4, RIL-175, and TIBx are broadly representative of human HCCs; however, Hepa 1-6 does not recapitulate the immune tumor microenvironment of the vast majority of human HCCs.
CONCLUSIONS
There is a wide diversity in the immune tumor microenvironments in preclinical models and in human HCC, highlighting the need to use multiple syngeneic HCC models to improve the understanding of how to treat HCC through immune modulation.
Topics: Animals; Humans; Mice; Carcinoma, Hepatocellular; Cell Line, Tumor; Immunotherapy; Liver Neoplasms; Tumor Microenvironment; Programmed Cell Death 1 Receptor
PubMed: 35941803
DOI: 10.1002/hep.32707 -
Molecular Metabolism Dec 2022Adipose tissue is the largest endocrine organ. When activated by cancer cells, adipocytes secrete adipocytokines and release fatty acids, which are then transferred to...
OBJECTIVE
Adipose tissue is the largest endocrine organ. When activated by cancer cells, adipocytes secrete adipocytokines and release fatty acids, which are then transferred to cancer cells and used for structural and biochemical support. How this metabolic symbiosis between cancer cells and adipocytes affects skeletal muscle and thermogenesis during cancer cachexia is unknown. Cancer cachexia is a multiorgan syndrome and how the communication between tissues is established has yet to be determined. We investigated adipose tissue secretory factors and explored their role in crosstalk of adipocytes, muscle, and tumor during pancreatic cancer cachexia.
METHODS
We used a pancreatic cancer cachexia mouse model generated by syngenic implantation of pancreatic ductal adenocarcinoma (PDAC) cells (KPC) intraperitoneally into C57BL/6 mice and Lcn2-knockout mice. For in vitro studies, adipocytes (3T3-L1 and primary adipocytes), cachectic cancer cells (Panc0203), non-cachectic cancer cells (Du145 cells), and skeletal muscle cells (C2C12 myoblasts) were used.
RESULTS
To identify molecules involved in the crosstalk of adipose tissue with muscle and tumors, we treated 3T3-L1 adipocytes with conditioned medium (CM) from cancer cells. Upon screening the secretomes from PDAC-induced adipocytes, several adipocytokines were identified, including lipocalin 2 (Lcn2). We investigated Lcn2 as a potential mediator of cachexia induced by adipocytes in response to PDAC. During tumor progression, mice exhibited a decline in body weight gain, which was accompanied by loss of adipose and muscle tissues. Tumor-harboring mice developed drastic hypothermia because of a dramatic loss of fat in brown adipose tissue (BAT) and suppression of the thermogenesis pathway. We inhibited Lcn2 with an anti-Lcn2 antibody neutralization or genomic ablation in mice. Lcn2 deficiency significantly improved body temperature in tumor-bearing mice, which was supported by the increased expression of Ucp1 and β3-adrenergic receptor in BAT. In addition, Lcn2 inhibition abrogated the loss of fat and muscle in tumor-bearing mice. In contrast to tumor-bearing WT mice, the corresponding Lcn2-knockout mice showed reduced ATGL expression in iWAT and decreased the expression of muscle atrophy molecular markers MuRF-1 and Fbx32.
CONCLUSIONS
This study showed that Lcn2 is causally involved in the dysregulation of adipose tissue-muscle-tumor crosstalk during pancreatic cancer cachexia. Therapeutic targets that suppress Lcn2 may minimize the progression of cachexia.
Topics: Animals; Mice; Adipocytes; Adipokines; Adipose Tissue, Brown; Cachexia; Hypothermia; Lipocalin-2; Mice, Inbred C57BL; Mice, Knockout; Muscle, Skeletal; Pancreatic Neoplasms
PubMed: 36243318
DOI: 10.1016/j.molmet.2022.101612 -
JCI Insight Jun 2022In many solid cancers, tumor-associated macrophages (TAM) represent the predominant myeloid cell population. Antigen (Ag) cross-presentation leading to tumor Ag-directed...
In many solid cancers, tumor-associated macrophages (TAM) represent the predominant myeloid cell population. Antigen (Ag) cross-presentation leading to tumor Ag-directed cytotoxic CD8+ T cell responses is crucial for antitumor immunity. However, the role of recruited monocyte-derived macrophages, including TAM, as potential cross-presenting cells is not well understood. Here, we show that primary human as well as mouse CD206+ macrophages are effective in functional cross-presentation of soluble self-Ag and non-self-Ag, including tumor-associated Ag (TAA), as well as viral Ag. To confirm the presence of cross-presenting TAM in vivo, we performed phenotypic and functional analysis of TAM from B16-F10 and CT26 syngeneic tumor models and have identified CD11b+F4/80hiCD206+ TAM to effectively cross-present TAA. We show that CD11b+CD206+ TAM represent the dominant tumor-infiltrating myeloid cell population, expressing a unique cell surface repertoire, promoting Ag cross-presentation and Ag-specific CD8+ T cell activation comparable with cross-presenting CLEC9A+ DCs (cDC1). The presence of cross-presenting CD206+ TAM is associated with reduced tumor burden in mouse syngeneic tumor models and with improved overall survival in cutaneous melanoma patients. Therefore, the demonstration of effective Ag cross-presentation capabilities of CD206+ TAM, including their clinical relevance, expands our understanding of TAM phenotypic diversity and functional versatility.
Topics: Animals; Antigens, Neoplasm; Cross-Priming; Humans; Melanoma; Mice; Skin Neoplasms; Tumor-Associated Macrophages
PubMed: 35503656
DOI: 10.1172/jci.insight.155022 -
Cancer Discovery Feb 2021Despite advances in immuno-oncology, the relationship between tumor genotypes and response to immunotherapy remains poorly understood, particularly in high-grade serous...
Despite advances in immuno-oncology, the relationship between tumor genotypes and response to immunotherapy remains poorly understood, particularly in high-grade serous tubo-ovarian carcinomas (HGSC). We developed a series of mouse models that carry genotypes of human HGSCs and grow in syngeneic immunocompetent hosts to address this gap. We transformed murine-fallopian tube epithelial cells to phenocopy homologous recombination-deficient tumors through a combined loss of and overexpression of and , which was contrasted with an identical model carrying wild-type . For homologous recombination-proficient tumors, we constructed genotypes combining loss of and overexpression of , and driven by or or overexpression. These lines form tumors recapitulating human disease, including genotype-driven responses to treatment, and enabled us to identify follistatin as a driver of resistance to checkpoint inhibitors. These data provide proof of concept that our models can identify new immunotherapy targets in HGSC. SIGNIFICANCE: We engineered a panel of murine fallopian tube epithelial cells bearing mutations typical of HGSC and capable of forming tumors in syngeneic immunocompetent hosts. These models recapitulate tumor microenvironments and drug responses characteristic of human disease. In a -overexpressing model, immune-checkpoint resistance was driven by follistatin..
Topics: Animals; Cystadenocarcinoma, Serous; Disease Models, Animal; Drug Therapy, Combination; Fallopian Tube Neoplasms; Female; Immune Checkpoint Inhibitors; Mice, Transgenic; Ovarian Neoplasms
PubMed: 33158843
DOI: 10.1158/2159-8290.CD-20-0818 -
Biology Methods & Protocols 2022While subcutaneous tumor models remain the standard for studying drug efficacy , these tumors rarely metastasize and lack physiological relevance due to differences in...
While subcutaneous tumor models remain the standard for studying drug efficacy , these tumors rarely metastasize and lack physiological relevance due to differences in the tumor microenvironment, vascularization, immune landscape, and physiological cues associated with the organ of interest. Orthotopic tumors, grown from the organ corresponding with the cancer type, provide a more translational approach to study disease progression and drug efficacy. Utilization of a syngeneic mouse model allows for a complete immune landscape, key for adaptive immunotherapy studies. MC38 and CT26 cells are commonly used murine colorectal cancer cell lines with clinically relevant mutations. While CT26 cells have been orthotopically implanted with high fidelity, successful engraftment of orthotopic MC38 tumors varies greatly between studies. Thus, we have developed a detailed protocol for MC38 orthotopic tumor inoculation via intracecal injection. Nine C57BL/6 mice were injected with 2 × 10 cells into the cecal wall and sacrificed after 7 weeks. Survival after surgery was 100%, and one mouse died before the 7-week study end point from tumor burden and metastatic spread. We observed a successful tumor engraftment rate of 67%. Half of mice presenting with tumors were found to have macroscopic metastatic lesions in clinically relevant foci, including the mesenteric lymph nodes, liver, and peritoneum. These mice also presented with very large tumors and an enlarged spleen. The other half of the mice presented with small, localized tumors that did not metastasize. Herein, we describe tips specific for the intracecal injection of MC38 cells to improve the engraftment rate consistency in this model.
PubMed: 36225595
DOI: 10.1093/biomethods/bpac024