ABSTRACT
Dysfunctional anti-tumor immunity has been implicated in the pathogenesis of mature B cell neoplasms, such as multiple myeloma and B cell lymphoma; however, the impact of exhausted T cells on disease development remains unclear. Therefore, the present study investigated the features and pathogenetic significance of exhausted T cells using a mouse model of de novo mature B cell neoplasms, which is likely to show immune escape similar to human patients. The results revealed a significant increase in PD-1+ Tim-3- and PD-1+ Tim-3+ T cells in sick mice. Furthermore, PD-1+ Tim-3+ T cells exhibited direct cytotoxicity with a short lifespan, showing transcriptional similarities to terminally exhausted T cells. On the other hand, PD-1+ Tim-3- T cells not only exhibited immunological responsiveness but also retained stem-like transcriptional features, suggesting that they play a role in the long-term maintenance of anti-tumor immunity. In PD-1+ Tim-3- and PD-1+ Tim-3+ T cells, the transcription factors Tox and Nr4a2, which reportedly contribute to the progression of T cell exhaustion, were up-regulated in vivo. These transcription factors were down-regulated by IMiDs in our in vitro T cell exhaustion analyses. The prevention of excessive T cell exhaustion may maintain effective anti-tumor immunity to cure mature B cell neoplasms.
Subject(s)
Lymphoma, B-Cell , Multiple Myeloma , Animals , Humans , Hepatitis A Virus Cellular Receptor 2 , CD8-Positive T-Lymphocytes , Programmed Cell Death 1 Receptor , Disease Models, Animal , Transcription FactorsABSTRACT
Cancer immunotherapy utilizes our immune system to attack cancer cells and is an extremely promising strategy for cancer treatment. Although immune-checkpoint blockade, such as anti-PD-1 (programmed cell death 1) antibody, has demonstrated significant enhancement of anti-tumor immunity and has induced notable clinical outcomes, its response rates remain low, and adverse effects are always a matter of concern; therefore, new targets for cancer immunotherapy are always desired. In this situation, new concepts are needed to fuel the investigation of new target molecules for cancer immunotherapy. We propose that CD69 is one such target molecule. CD69 is known to be an activation marker of leukocytes and is also considered a crucial regulator of various immune responses through its interacting proteins. CD69 promotes T-cell retention in lymphoid tissues via sphingosine-1-phosphate receptor 1 (S1P1) internalization and also plays roles in the pathogenesis of inflammatory disorders through interacting with its functional ligands Myl9/12 (myosin light chains 9, 12a and 12b). In anti-tumor immunity, CD69 is known to be expressed on T cells in the tumor microenvironment (TME) and tumor-draining lymph nodes (TDLNs). We revealed that CD69 negatively regulates the effector function of intratumoral T cells and importantly controls the 'exhaustion' of CD8 T cells. In addition, we and others showed that either CD69 deficiency or the administration of anti-CD69 monoclonal antibody enhances anti-tumor immunity. Thus, CD69 is an attractive target for cancer immunotherapy.
Subject(s)
Immune Checkpoint Inhibitors , Myosin Light Chains , Antibodies, Monoclonal/therapeutic use , CD8-Positive T-Lymphocytes/metabolism , Immunotherapy , Myosin Light Chains/metabolism , Sphingosine-1-Phosphate Receptors , Tumor MicroenvironmentABSTRACT
Glioblastoma is the most common and aggressive type of brain tumor with high recurrence and fatality rates. Although various therapeutic strategies have been explored, there is currently no effective treatment for glioblastoma. Recently, the number of immunotherapeutic strategies has been tested for malignant brain tumors. Invariant natural killer T (iNKT) cells play an important role in anti-tumor immunity. To address if iNKT cells can target glioblastoma to exert anti-tumor activity, we assessed the expression of CD1d, an antigen-presenting molecule for iNKT cells, on glioblastoma cells. Glioblastoma cells from 10 of 15 patients expressed CD1d, and CD1d-positive glioblastoma cells pulsed with glycolipid ligand induced iNKT cell-mediated cytotoxicity in vitro. Although CD1d expression was low on glioblastoma stem-like cells, retinoic acid, which is the most common differentiating agent, upregulated CD1d expression in these cells and induced iNKT cell-mediated cytotoxicity. Moreover, intracranial administration of human iNKT cells induced tumor regression of CD1d-positive glioblastoma in orthotopic xenografts in NOD/Shi-scid IL-2RγKO (NOG) mice. Thus, CD1d expression represents a novel target for NKT cell-based immunotherapy for glioblastoma patients.
Subject(s)
Antigens, CD1d/metabolism , Brain Neoplasms/immunology , Cancer Vaccines/immunology , Glioblastoma/immunology , Immunotherapy, Adoptive/methods , Natural Killer T-Cells/metabolism , Aged , Animals , Antigen Presentation , Brain Neoplasms/therapy , Cells, Cultured , Cytotoxicity, Immunologic , Female , Gene Expression Regulation, Neoplastic , Glioblastoma/therapy , Humans , Male , Mice , Mice, SCID , Middle Aged , Natural Killer T-Cells/immunology , Natural Killer T-Cells/transplantation , Neoplasm Transplantation , Tretinoin/metabolismABSTRACT
Invariant natural killer T (iNKT) cells are innate-like CD1d-restricted T cells that express the invariant T cell receptor (TCR) composed of Vα24 and Vß11 in humans. iNKT cells specifically recognize glycolipid antigens such as α-galactosylceramide (αGalCer) presented by CD1d. iNKT cells show direct cytotoxicity toward CD1d-positive tumor cells, especially when CD1d presents glycolipid antigens. However, iNKT cell recognition of CD1d-negative tumor cells is unknown, and direct cytotoxicity of iNKT cells toward CD1d-negative tumor cells remains controversial. Here, we demonstrate that activated iNKT cells recognize leukemia cells in a CD1d-independent manner, however still in a TCR-mediated way. iNKT cells degranulated and released Th1 cytokines toward CD1d-negative leukemia cells (K562, HL-60, REH) as well as αGalCer-loaded CD1d-positive Jurkat cells. The CD1d-independent cytotoxicity was enhanced by natural killer cell-activating receptors such as NKG2D, 2B4, DNAM-1, LFA-1 and CD2, but iNKT cells did not depend on these receptors for the recognition of CD1d-negative leukemia cells. In contrast, TCR was essential for CD1d-independent recognition and cytotoxicity. iNKT cells degranulated toward patient-derived leukemia cells independently of CD1d expression. iNKT cells targeted myeloid malignancies more than acute lymphoblastic leukemia. These findings reveal a novel anti-tumor mechanism of iNKT cells in targeting CD1d-negative tumor cells and indicate the potential of iNKT cells for clinical application to treat leukemia independently of CD1d.
Subject(s)
Antigens, CD1d/metabolism , Leukemia/immunology , Leukemia/metabolism , Lymphocyte Activation/immunology , Natural Killer T-Cells/immunology , Natural Killer T-Cells/metabolism , Animals , Antigens, CD1d/genetics , Biomarkers , Cell Degranulation , Cell Line, Tumor , Costimulatory and Inhibitory T-Cell Receptors/metabolism , Cytokines/metabolism , Cytotoxicity, Immunologic , Disease Models, Animal , Female , Gene Editing , Heterografts , Humans , Immunophenotyping , Leukemia/genetics , Leukemia/pathology , Lymphocyte Activation/genetics , Mice , Receptors, Antigen, T-Cell/genetics , Receptors, Antigen, T-Cell/metabolism , Receptors, Natural Cytotoxicity Triggering/metabolismABSTRACT
Glioblastoma is one of the most aggressive forms of cancers and has a poor prognosis. Genomewide analyses have revealed that a set of core signaling pathways, the p53, RB, and RTK pathways, are commonly deregulated in glioblastomas. However, the molecular mechanisms underlying the tumorigenicity of glioblastoma are not fully understood. Here, we show that the lysine deacetylase SIRT2 is required for the proliferation and tumorigenicity of glioblastoma cells, including glioblastoma stem cells. Furthermore, we demonstrate that SIRT2 regulates p73 transcriptional activity by deacetylation of its C-terminal lysine residues. Our results suggest that SIRT2-mediated inactivation of p73 is critical for the proliferation and tumorigenicity of glioblastoma cells and that SIRT2 may be a promising molecular target for the therapy of glioblastoma.
Subject(s)
Brain Neoplasms/pathology , Glioblastoma/pathology , Sirtuin 2/metabolism , Tumor Protein p73/metabolism , Acetylation , Animals , Apoptosis/drug effects , Apoptosis/genetics , Brain Neoplasms/metabolism , Cell Proliferation , Furans/pharmacology , Gene Knockdown Techniques , Glioblastoma/metabolism , Humans , Lysine/metabolism , Mice, Nude , Neoplastic Stem Cells/metabolism , Neoplastic Stem Cells/pathology , Quinolines/pharmacology , Sirtuin 2/antagonists & inhibitors , Sirtuin 2/genetics , Tumor Cells, Cultured , Tumor Protein p73/genetics , Xenograft Model Antitumor AssaysABSTRACT
The introduction of immune checkpoint inhibitors in cancer treatment highlights the negative regulation of anti-tumor immunity, such as effector T-cell exhaustion in the tumor microenvironment. However, the mechanisms underlying the induction and prevention of T-cell exhaustion remain largely unknown. We found that CD69, a type II glycoprotein known to regulate inflammation through T-cell migration and retention in tissues, plays an important role in inducing the exhaustion of tumor-infiltrating T cells. Cd69-/- mice showed reduced tumor growth and metastasis in a 4T1-luc2 murine breast cancer model, in which increased numbers of tumor-infiltrating lymphocytes, relatively little T-cell exhaustion, and enhanced IFNγ production were observed. Anti-CD69 monoclonal antibody treatment attenuated the T-cell exhaustion and tumor progression in tumor-bearing mice. These findings highlight a novel role of CD69 in controlling the tumor immune escape mediated by T-cell exhaustion and indicate that CD69 is a novel target for cancer immunotherapy.
Subject(s)
Antigens, CD/immunology , Antigens, Differentiation, T-Lymphocyte/immunology , Breast Neoplasms/immunology , Lectins, C-Type/immunology , Lymphocytes, Tumor-Infiltrating/immunology , Animals , Breast Neoplasms/pathology , Cells, Cultured , Female , Lectins, C-Type/deficiency , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Mice, KnockoutABSTRACT
Mycobacterium bovis Bacille Calmette-Guérin (BCG) has been shown to possess potent anti-tumor activity particularly in various animal models, while the cellular and molecular mechanisms underlying its activity are not well understood. We found that lipomannan (BCG-LM), a lipophilic component of the mycobacterial cell envelope, specifically inhibits tumor growth and induces the infiltration of eosinophils at local tumor invasion sites. In contrast, neither lipoarabinomannan (BCG-LAM) nor the cell wall of Mycobacterium bovis BCG (BCG-CW) exerted anti-tumor immunity. BCG-LM enhances cytotoxic activity of eosinophils via the increased production of superoxide. Global transcriptomic analyses of BCG-LM-pulsed dendritic cells identified C-C motif ligand (CCL) 5 as a crucial chemokine for the anti-tumor immunity induced by BCG-LM, indicating that CCL5 plays an important role for the accumulation of eosinophils in the tumor microenvironment. Furthermore, BCG-LM and memory Th2 cells exerted a synergetic effect on tumor progression by cooperatively enhancing the eosinophil function. Thus, this study revealed an un-identified BCG-LM-mediated anti-tumor mechanism via superoxide produced by infiltrated eosinophils in the tumor microenvironment. Since BCG-LM activates this unique pathway, it may have potent therapeutic potential as immune cell therapy for cancer patients.
Subject(s)
Dendritic Cells/immunology , Eosinophils/immunology , Immunotherapy, Adoptive/methods , Lipopolysaccharides/immunology , Mycobacterium bovis/immunology , Neoplasms, Experimental/immunology , Superoxides/metabolism , Th2 Cells/immunology , Animals , Carcinogenesis , Cell Line, Tumor , Cell Movement , Cell Wall/immunology , Chemokine CCL5/metabolism , Cytotoxicity, Immunologic , Female , Immunologic Memory , Mice , Mice, Inbred BALB C , Neoplasms, Experimental/therapy , Transcriptome , Tumor Burden , Tumor MicroenvironmentABSTRACT
Glioblastoma is one of the most malignant brain tumors with poor prognosis and their development and progression are known to be driven by glioblastoma stem cells. Although glioblastoma stem cells lose their cancer stem cell properties during cultivation in serum-containing medium, little is known about the molecular mechanisms regulating signaling alteration in relation to reduction of stem cell-like characteristics. To elucidate the global phosphorylation-related signaling events, we performed a SILAC-based quantitative phosphoproteome analysis of serum-induced dynamics in glioblastoma stem cells established from the tumor tissues of the patient. Among a total of 2876 phosphorylation sites on 1584 proteins identified in our analysis, 732 phosphorylation sites on 419 proteins were regulated through the alteration of stem cell-like characteristics. The integrative computational analyses based on the quantified phosphoproteome data revealed the relevant changes of phosphorylation levels regarding the proteins associated with cytoskeleton reorganization such as Rho family GTPase and Intermediate filament signaling, in addition to transforming growth factor-ß receptor type-2 (TGFBR2) as a prominent upstream regulator involved in the serum-induced phosphoproteome regulation. The functional association of transforming growth factor-ß receptor type-2 with stem cell-like properties was experimentally validated through signaling perturbation using the corresponding inhibitors, which indicated that transforming growth factor-ß receptor type-2 could play an important role as a novel cell fate determinant in glioblastoma stem cell regulation.
Subject(s)
Brain Neoplasms/metabolism , Glioblastoma/pathology , Neoplastic Stem Cells/metabolism , Protein Serine-Threonine Kinases/metabolism , Proteomics/methods , Receptors, Transforming Growth Factor beta/metabolism , Cell Proliferation , Computational Biology/methods , Culture Media/pharmacology , Gene Expression Regulation, Neoplastic , Glioblastoma/metabolism , Humans , Phosphorylation , Receptor, Transforming Growth Factor-beta Type II , Serum , Signal TransductionABSTRACT
Lineage specification is primarily regulated at the transcriptional level and lineage-specific transcription factors determine cell fates. MicroRNAs (miRNAs) are 18-24 nucleotide-long non-coding RNAs that post-transcriptionally decrease the translation of target mRNAs and are essential for many cellular functions. miRNAs also regulate lineage specification during hematopoiesis. This review highlights the roles of miRNAs in B-cell development and malignancies, and discusses how miRNA expression profiles correlate with disease prognoses and phenotypes. We also discuss the potential for miRNAs as therapeutic targets and diagnostic tools for B-cell malignancies.
Subject(s)
Hematopoiesis/physiology , MicroRNAs/metabolism , Animals , B-Lymphocytes/metabolism , Hematopoiesis/genetics , Humans , Leukemia/genetics , Leukemia/metabolism , Lymphoma/genetics , Lymphoma/metabolism , MicroRNAs/geneticsABSTRACT
Upon binding of a Wnt ligand to the frizzled (FZD)-low density lipoprotein receptor related protein 5/6 (LRP5/6) receptor complex, the ß-catenin destruction complex, composed of Axin1, adenomatous polyposis coli (APC), glycogen synthase kinase 3 (GSK3) and casein kinase 1 (CK1), is immediately inactivated, which causes ß-catenin stabilization. However, the molecular mechanism of signal transduction from the receptor complex to the ß-catenin destruction complex is controversial. Here we show that Wnt3a treatment promotes the dissociation of the Axin1-APC complex in glioblastoma cells cultured in serum-free medium. Experiments with the GSK3 inhibitor BIO suggest that Axin1-APC dissociation was controlled by phosphorylation. Introduction of a phosphomimetic mutation into Thr160 of Axin1, located in the APC-binding region RGS, abrogated the interaction of Axin1 with APC. Consistent with these observations, the Axin1 phosphomimetic mutant lost the ability to reduce ß-catenin stability and to repress ß-catenin/TCF-dependent transcription. Taken together, our results suggest a novel mechanism of Wnt signaling through the dissociation of the ß-catenin destruction complex by Axin1 Thr160 modification.
Subject(s)
Axin Protein/chemistry , Axin Protein/metabolism , Axin Signaling Complex/chemistry , Axin Signaling Complex/metabolism , Adenomatous Polyposis Coli Protein/chemistry , Adenomatous Polyposis Coli Protein/metabolism , Axin Protein/genetics , Binding Sites , Biomimetic Materials/chemistry , Biomimetic Materials/metabolism , Casein Kinase I/chemistry , Casein Kinase I/metabolism , Cell Line, Tumor , Glioblastoma/metabolism , Glycogen Synthase Kinase 3/chemistry , Glycogen Synthase Kinase 3/metabolism , HEK293 Cells , Humans , Low Density Lipoprotein Receptor-Related Protein-5/antagonists & inhibitors , Low Density Lipoprotein Receptor-Related Protein-5/genetics , Low Density Lipoprotein Receptor-Related Protein-5/metabolism , Low Density Lipoprotein Receptor-Related Protein-6/antagonists & inhibitors , Low Density Lipoprotein Receptor-Related Protein-6/genetics , Low Density Lipoprotein Receptor-Related Protein-6/metabolism , Mutagenesis, Site-Directed , Phosphorylation , Protein Stability , RNA, Small Interfering/genetics , Threonine/chemistry , Wnt Signaling Pathway , beta Catenin/chemistry , beta Catenin/metabolismABSTRACT
LGR5 plays an important role in the self-renewal of stem cells and is used as a marker identifying self-renewing stem cells in small intestine and hair follicles. Moreover, LGR5 has been reported to be overexpressed in several cancers. SOX9 is a transcription factor that plays a key role in development, differentiation and lineage commitment in various tissues. It has also been reported that SOX9 is overexpressed in a variety of cancers and contributes to their malignant phenotype. Here we show that LGR5 is required for the tumorigenicity of glioblastoma cells. We further show that SOX9 is upregulated in glioblastoma cells and directly enhances the expression of LGR5. We also demonstrate that knockdown of SOX9 suppresses the proliferation and tumorigenicity of glioblastoma cells. These results suggest that SOX9-mediated transcriptional regulation of LGR5 is critical for the tumorigenicity of glioblastoma cells. We speculate that the SOX9-LGR5 pathway could be a potentially promising target for the therapy of glioblastoma.
Subject(s)
Brain Neoplasms/metabolism , Glioblastoma/metabolism , Receptors, G-Protein-Coupled/physiology , SOX9 Transcription Factor/physiology , Up-Regulation/physiology , Brain Neoplasms/pathology , Cell Line, Tumor , Gene Knockdown Techniques , Glioblastoma/pathology , Humans , Receptors, G-Protein-Coupled/genetics , SOX9 Transcription Factor/geneticsABSTRACT
Protocadherin10 (PCDH10)/OL-protocadherin is a cadherin-related transmembrane protein that has multiple roles in the brain, including facilitating specific cell-cell connections, cell migration and axon guidance. It has recently been reported that PCDH10 functions as a tumor suppressor and that its overexpression inhibits proliferation or invasion of multiple tumor cells. However, the function of PCDH10 in glioblastoma cells has not been elucidated. In contrast to previous reports on other tumors, we show here that suppression of the expression of PCDH10 by RNA interference (RNAi) induces the growth arrest and apoptosis of glioblastoma cells in vitro. Furthermore, we demonstrate that knockdown of PCDH10 inhibits the growth of glioblastoma cells xenografted into immunocompromised mice. These results suggest that PCDH10 is required for the proliferation and tumorigenicity of glioblastoma cells. We speculate that PCDH10 may be a promising target for the therapy of glioblastoma.
Subject(s)
Brain Neoplasms/metabolism , Brain Neoplasms/pathology , Cadherins/metabolism , Glioblastoma/metabolism , Glioblastoma/pathology , Animals , Apoptosis , Brain Neoplasms/genetics , Cadherins/antagonists & inhibitors , Cadherins/genetics , Cell Line, Tumor , Cell Proliferation , Gene Knockdown Techniques , Glioblastoma/genetics , Heterografts , Humans , Mice , Mice, Nude , Neoplasm Invasiveness , Oncogene Proteins/antagonists & inhibitors , Oncogene Proteins/genetics , Oncogene Proteins/metabolism , Protocadherins , RNA InterferenceABSTRACT
c-Jun is a component of the heterodimeric transcription factor AP-1 that is rapidly activated in response to ultraviolet light (UV). In unstressed cells, c-Jun activity is negatively regulated by transcriptional repressor complexes. Here we show that the F-box protein Fbl10/JHDM1B interacts with c-Jun and represses c-Jun-mediated transcription. Chromatin-immunoprecipitation assays demonstrate that Fbl10 is present at the c-jun promoter, and that c-Jun is required for the recruitment of Fbl10. Fbl10 binds to the unmethylated CpG sequences in the c-jun promoter through the CxxC zinc finger and tethers transcriptional repressor complexes. Suppression of Fbl10 expression by RNA interference (RNAi) induces transcription of c-jun and other c-Jun-target genes, and causes an aberrant cell-cycle progression and increased UV-induced cell death. Furthermore, Fbl10 protein and messenger RNA are downregulated in response to UV in an inverse correlation with c-Jun. Taken together, our results demonstrate that Fbl10 is a key regulator of c-Jun function.
Subject(s)
F-Box Proteins/metabolism , Gene Expression Regulation, Enzymologic , JNK Mitogen-Activated Protein Kinases/metabolism , Oxidoreductases, N-Demethylating/metabolism , Protein Isoforms/metabolism , Transcription, Genetic , Amino Acid Sequence , Animals , Cell Line , F-Box Proteins/genetics , Humans , JNK Mitogen-Activated Protein Kinases/genetics , Jumonji Domain-Containing Histone Demethylases , Molecular Sequence Data , Oxidoreductases, N-Demethylating/genetics , Promoter Regions, Genetic , Protein Isoforms/genetics , RNA Interference , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/metabolism , Sequence AlignmentABSTRACT
JHDM1B is an evolutionarily conserved and ubiquitously expressed member of the JHDM (JmjC-domain-containing histone demethylase) family. Because it contains an F-box motif, this protein is also known as FBXL10 (ref. 4). With the use of a genome-wide RNAi screen, the JHDM1B worm orthologue (T26A5.5) was identified as a gene that regulates growth. In the mouse, four independent screens have identified JHDM1B as a putative tumour suppressor by retroviral insertion analysis. Here we identify human JHDM1B as a nucleolar protein and show that JHDM1B preferentially binds the transcribed region of ribosomal DNA to repress the transcription of ribosomal RNA genes. We also show that repression of ribosomal RNA genes by JHDM1B is dependent on its JmjC domain, which is necessary for the specific demethylation of trimethylated lysine 4 on histone H3 in the nucleolus. In agreement with the notion that ribosomal RNA synthesis and cell growth are coupled processes, we show a JmjC-domain-dependent negative effect of JHDM1B on cell size and cell proliferation. Because aberrant ribosome biogenesis and the disruption of epigenetic control mechanisms contribute to cellular transformation, these results, together with the low levels of JHDM1B expression found in aggressive brain tumours, suggest a role for JHDM1B in cancer development.
Subject(s)
Cell Nucleolus/metabolism , DNA, Ribosomal/genetics , F-Box Proteins/metabolism , Genes, rRNA/genetics , Nuclear Proteins/metabolism , Oxidoreductases, N-Demethylating/metabolism , Repressor Proteins/metabolism , Transcription, Genetic , Cell Proliferation , DNA, Ribosomal/metabolism , Down-Regulation , F-Box Proteins/chemistry , HeLa Cells , Histones/metabolism , Humans , Jumonji Domain-Containing Histone Demethylases , Methylation , Nuclear Proteins/chemistry , Oxidoreductases, N-Demethylating/chemistry , Protein Structure, Tertiary , RNA Interference , Repressor Proteins/chemistryABSTRACT
Tumor-specific CD8+ T cells play a pivotal role in antitumor immunity and are a key target of immunotherapeutic approaches. Intratumoral CD8+ T cells are heterogeneous; Tcf1+ stemlike CD8+ T cells give rise to their cytotoxic progeny-Tim-3+ terminally differentiated CD8+ T cells. However, where and how this differentiation process occurs has not been elucidated. We herein show that terminally differentiated CD8+ T cells can be generated within tumor-draining lymph nodes (TDLN) and that CD69 expression on tumor-specific CD8+ T cells controls its differentiation process through regulating the expression of the transcription factor TOX. In TDLNs, CD69 deficiency diminished TOX expression in tumor-specific CD8+ T cells, and consequently promoted generation of functional terminally differentiated CD8+ T cells. Anti-CD69 administration promoted the generation of terminally differentiated CD8+ T cells, and the combined use of anti-CD69 and anti-programmed cell death protein 1 (PD-1) showed an efficient antitumor effect. Thus, CD69 is an attractive target for cancer immunotherapy that synergizes with immune checkpoint blockade.
Subject(s)
CD8-Positive T-Lymphocytes , Neoplasms , Humans , Neoplasms/therapy , Neoplasms/pathology , Cell Differentiation , Lymph NodesABSTRACT
While IFNγ is a well-known cytokine that actively promotes the type I immune response, it is also known to suppress the type II response by inhibiting the differentiation and proliferation of Th2 cells. However, the mechanism by which IFNγ suppresses Th2 cell proliferation is still not fully understood. We found that IFNγ decreases the expression of growth factor independent-1 transcriptional repressor (GFI1) in Th2 cells, resulting in the inhibition of Th2 cell proliferation. The deletion of the Gfi1 gene in Th2 cells results in the failure of their proliferation, accompanied by an impaired cell cycle progression. In contrast, the enforced expression of GFI1 restores the defective Th2 cell proliferation, even in the presence of IFNγ. These results demonstrate that GFI1 is a key molecule in the IFNγ-mediated inhibition of Th2 cell proliferation.
Subject(s)
DNA-Binding Proteins/genetics , Interferon-gamma/immunology , Th2 Cells/cytology , Transcription Factors/genetics , Animals , Cell Cycle , Cell Proliferation , Cells, Cultured , Down-Regulation , Gene Deletion , Mice , Mice, Inbred C57BL , Th2 Cells/immunology , Th2 Cells/metabolismABSTRACT
MicroRNAs (miRNAs), one of small non-coding RNAs, regulate many cell functions through their post-transcriptionally downregulation of target genes. Accumulated studies have revealed that miRNAs are involved in hematopoiesis. In the present study, we investigated effects of miR-669m overexpression on hematopoiesis in mouse in vivo, and found that erythroid differentiation was inhibited by the overexpression. Our bioinformatic analyses showed that candidate targets of miR-669m which are involved in the erythropoiesis inhibition are A-kinase anchoring protein 7 (Akap7) and X-linked Kx blood group (Xk) genes. These two genes were predicted as targets of miR-669m by two different in silico methods and were upregulated in late erythroblasts in a public RNA-seq data, which was confirmed with qPCR. Further, miR-669m suppressed luciferase reporters for 3' untranslated regions of Akap7 and Xk genes, which supports these genes are direct targets of miR-669m. Physiologically, miR-669m was not expressed in the erythroblast. In conclusion, using miR-669m, we found Akap7 and Xk, which may be involved in erythroid differentiation, implying that manipulating these genes could be a therapeutic way for diseases associated with erythropoiesis dysfunction.
Subject(s)
A Kinase Anchor Proteins/metabolism , Amino Acid Transport Systems, Neutral/metabolism , Cell Differentiation , Erythroblasts/cytology , Erythropoiesis , MicroRNAs/genetics , A Kinase Anchor Proteins/genetics , Amino Acid Transport Systems, Neutral/genetics , Animals , Erythroblasts/metabolism , Female , Mice , Mice, Inbred C57BLABSTRACT
Memory helper T (Th) cells are crucial for secondary immune responses against infectious microorganisms but also drive the pathogenesis of chronic inflammatory diseases. Therefore, it is of fundamental importance to understand how memory T cells are generated. However, the molecular mechanisms governing memory Th cell generation remain incompletely understood. Here, we identified CD30 as a molecule heterogeneously expressed on effector Th1 and Th17 cells, and CD30hi effector Th1 and Th17 cells preferentially generated memory Th1 and Th17 cells. We found that CD30 mediated signal induced Transglutaminase-2 (TG2) expression, and that the TG2 expression in effector Th cells is essential for memory Th cell generation. In fact, Cd30-deficiency resulted in the impaired generation of memory Th1 and Th17 cells, which can be rescued by overexpression of TG2. Furthermore, transglutaminase-2 (Tgm2)-deficient CD4 T cells failed to become memory Th cells. As a result, T cells from Tgm2-deficient mice displayed impaired antigen-specific antibody production and attenuated Th17-mediated allergic responses. Our data indicate that CD30-induced TG2 expression in effector Th cells is essential for the generation of memory Th1 and Th17 cells, and that CD30 can be a marker for precursors of memory Th1 and Th17 cells.
Subject(s)
GTP-Binding Proteins/metabolism , Immunologic Memory , Ki-1 Antigen/metabolism , Th1 Cells/immunology , Th1 Cells/metabolism , Th17 Cells/immunology , Th17 Cells/metabolism , Transglutaminases/metabolism , Adoptive Transfer , Animals , Cell Differentiation/immunology , Immunophenotyping , Mice , Mice, Transgenic , Protein Glutamine gamma Glutamyltransferase 2 , Signal Transduction , Th1 Cells/cytology , Th17 Cells/cytologyABSTRACT
CD69 is an activation marker on leukocytes. Early studies showed that the CD69+ cells were detected in the lung of patients with asthmatic and eosinophilic pneumonia, suggesting that CD69 might play crucial roles in the pathogenesis of such inflammatory diseases, rather than simply being an activation marker. Intensive studies using mouse models have since clarified that CD69 is a functional molecule regulating the immune responses. We discovered that Myosin light chain 9, 12a, 12b (Myl9/12) are ligands for CD69 and that platelet-derived Myl9 forms a net-like structure (Myl9 nets) that is strongly detected inside blood vessels in inflamed lung. CD69-expressing activated T cells attached to the Myl9 nets can thereby migrate into the inflamed tissues through a system known as the CD69-Myl9 system. In this review, we summarize the discovery of the CD69-Myl9 system and discuss how this system is important in inflammatory immune responses. In addition, we discuss our recent finding that CD69 controls the exhaustion status of tumor-infiltrating T cells and that the blockade of the CD69 function enhances anti-tumor immunity. Finally, we discuss the possibility of CD69 as a new therapeutic target for patients with intractable inflammatory disorders and tumors.
Subject(s)
Antigens, CD/metabolism , Antigens, Differentiation, T-Lymphocyte/metabolism , Biomarkers , Immunity , Lectins, C-Type/metabolism , Myosin Light Chains/metabolism , Animals , Antigens, CD/chemistry , Antigens, CD/genetics , Antigens, CD/immunology , Antigens, Differentiation, T-Lymphocyte/chemistry , Antigens, Differentiation, T-Lymphocyte/genetics , Antigens, Differentiation, T-Lymphocyte/immunology , Cell Transformation, Neoplastic , Disease Susceptibility , Gene Expression , Humans , Inflammation/etiology , Inflammation/metabolism , Inflammation/pathology , Lectins, C-Type/chemistry , Lectins, C-Type/genetics , Lectins, C-Type/immunology , Ligands , Molecular Targeted Therapy , Myosin Light Chains/chemistry , Myosin Light Chains/genetics , Myosin Light Chains/immunology , Neoplasms/etiology , Neoplasms/metabolism , Neoplasms/pathology , Protein Binding , Respiratory Hypersensitivity/etiology , Respiratory Hypersensitivity/metabolism , Respiratory Hypersensitivity/pathology , Structure-Activity RelationshipABSTRACT
Immunological memory is central to adaptive immunity and protection from disease. Changing metabolic demands as antigen-specific T cells transition from effector to memory cells have been well documented, but the cell-specific pathways and molecules that govern this transition are poorly defined. Here we show that genetic deletion of ACC1, a rate-limiting enzyme in fatty acid biosynthesis, enhances the formation of CD4+ T memory cells. ACC1-deficient effector helper T (Th) cells have similar metabolic signatures to wild-type memory Th cells, and expression of the gene encoding ACC1, Acaca, was inversely correlated with a memory gene signature in individual cells. Inhibition of ACC1 function enhances memory T cell formation during parasite infection in mice. Using single-cell analyses we identify a memory precursor-enriched population (CCR7hiCD137lo) present during early differentiation of effector CD4+ T cells. Our data indicate that fatty acid metabolism directs cell fate determination during the generation of memory CD4+ T cells.