1
|
Rodriguez BN, Huang H, Chia JJ, Hoffmann A. The noncanonical NFκB pathway: Regulatory mechanisms in health and disease. WIREs Mech Dis 2024; 16:e1646. [PMID: 38634218 PMCID: PMC11486840 DOI: 10.1002/wsbm.1646] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 03/29/2024] [Accepted: 04/01/2024] [Indexed: 04/19/2024]
Abstract
The noncanonical NFκB signaling pathway mediates the biological functions of diverse cell survival, growth, maturation, and differentiation factors that are important for the development and maintenance of hematopoietic cells and immune organs. Its dysregulation is associated with a number of immune pathologies and malignancies. Originally described as the signaling pathway that controls the NFκB family member RelB, we now know that noncanonical signaling also controls NFκB RelA and cRel. Here, we aim to clarify our understanding of the molecular network that mediates noncanonical NFκB signaling and review the human diseases that result from a deficient or hyper-active noncanonical NFκB pathway. It turns out that dysregulation of RelA and cRel, not RelB, is often implicated in mediating the resulting pathology. This article is categorized under: Immune System Diseases > Molecular and Cellular Physiology Cancer > Molecular and Cellular Physiology Immune System Diseases > Stem Cells and Development.
Collapse
|
2
|
Xu K, Kessler A, Nichetti F, Hoffmeister-Wittmann P, Scherr AL, Nader L, Kelmendi E, Schmitt N, Schwab M, García-Beccaria M, Sobol B, Nieto OA, Isele H, Gärtner U, Vaquero-Siguero N, Volk J, Korell F, Mock A, Heide D, Ramadori P, Lenoir B, Albrecht T, Hüllein J, Jäger D, Fröhling S, Springfeld C, Jackstadt R, Heikenwälder M, Dill MT, Roessler S, Goeppert B, Köhler BC. Lymphotoxin beta-activated LTBR/NIK/RELB axis drives proliferation in cholangiocarcinoma. Liver Int 2024; 44:2950-2963. [PMID: 39164890 DOI: 10.1111/liv.16069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/21/2024] [Revised: 07/25/2024] [Accepted: 08/02/2024] [Indexed: 08/22/2024]
Abstract
BACKGROUND AND AIMS Cholangiocarcinoma (CCA) is an aggressive malignancy arising from the intrahepatic (iCCA) or extrahepatic (eCCA) bile ducts with poor prognosis and limited treatment options. Prior evidence highlighted a significant contribution of the non-canonical NF-κB signalling pathway in initiation and aggressiveness of different tumour types. Lymphotoxin-β (LTβ) stimulates the NF-κB-inducing kinase (NIK), resulting in the activation of the transcription factor RelB. However, the functional contribution of the non-canonical NF-κB signalling pathway via the LTβ/NIK/RelB axis in CCA carcinogenesis and progression has not been established. METHODS Human CCA-derived cell lines and organoids were examined to determine the expression of NF-κB pathway components upon activation or inhibition. Proliferation and cell death were analysed using real-time impedance measurement and flow cytometry. Immunoblot, qRT-PCR, RNA sequencing and in situ hybridization were employed to analyse gene and protein expression. Four in vivo models of iCCA were used to probe the activation and regulation of the non-canonical NF-κB pathway. RESULTS Exposure to LTα1/β2 activates the LTβ/NIK/RelB axis and promotes proliferation in CCA. Inhibition of NIK with the small molecule inhibitor B022 efficiently suppresses RelB expression in patient-derived CCA organoids and nuclear co-translocation of RelB and p52 stimulated by LTα1/β2 in CCA cell lines. In murine CCA, RelB expression is significantly increased and LTβ is the predominant ligand of the non-canonical NF-κB signalling pathway. CONCLUSIONS Our study confirms that the non-canonical NF-κB axis LTβ/NIK/RelB drives cholangiocarcinogenesis and represents a candidate therapeutic target.
Collapse
|
3
|
Geiselhöringer AL, Kolland D, Patt AJ, Hammann L, Köhler A, Kreft L, Wichmann N, Hils M, Ruedl C, Riemann M, Biedermann T, Anz D, Diefenbach A, Voehringer D, Schmidt-Weber CB, Straub T, Pasztoi M, Ohnmacht C. Dominant immune tolerance in the intestinal tract imposed by RelB-dependent migratory dendritic cells regulates protective type 2 immunity. Nat Commun 2024; 15:9143. [PMID: 39443450 PMCID: PMC11500181 DOI: 10.1038/s41467-024-53112-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2023] [Accepted: 10/02/2024] [Indexed: 10/25/2024] Open
Abstract
Dendritic cells (DCs) are crucial for initiating protective immune responses and have also been implicated in the generation and regulation of Foxp3+ regulatory T cells (Treg cells). Here, we show that in the lamina propria of the small intestine, the alternative NF-κB family member RelB is necessary for the differentiation of cryptopatch and isolated lymphoid follicle-associated DCs (CIA-DCs). Moreover, single-cell RNA sequencing reveals a RelB-dependent signature in migratory DCs in mesenteric lymph nodes favoring DC-Treg cell interaction including elevated expression and release of the chemokine CCL22 from RelB-deficient conventional DCs (cDCs). In line with the key role of CCL22 to facilitate DC-Treg cell interaction, RelB-deficient DCs have a selective advantage to interact with Treg cells in an antigen-specific manner. In addition, DC-specific RelB knockout animals show increased total Foxp3+ Treg cell numbers irrespective of inflammatory status. Consequently, DC-specific RelB knockout animals fail to mount protective Th2-dominated immune responses in the intestine after infection with Heligmosomoides polygyrus bakeri. Thus, RelB expression in cDCs acts as a rheostat to establish a tolerogenic set point that is maintained even during strong type 2 immune conditions and thereby is a key regulator of intestinal homeostasis.
Collapse
|
4
|
Sun W, Xu K, Li X, Qian P, Xu F, Zhang Y, Wang X, Xu Z, Ding J, Xu X, Wei X, Jiang Q, Xu Y. Insight into prostate cancer osteolytic metastasis by RelB coordination of IL-8 and S100A4. Clin Transl Med 2024; 14:e70058. [PMID: 39415352 PMCID: PMC11483529 DOI: 10.1002/ctm2.70058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2024] [Revised: 09/27/2024] [Accepted: 10/03/2024] [Indexed: 10/18/2024] Open
Abstract
BACKGROUND Although RANK-LRANK interaction is essential for osteoclastogenesis, the mechanisms by which cancer cells invade bone tissues and initiate osteolytic metastasis remain unclear. Here, we show that the hyperactivation of RelB fosters prostate cancer (PCa) osteolytic metastasis by coordinating interleukin-8 (IL-8) and calcium-binging protein A4 (S100A4). METHODS The factors promoting PCa bone metastasis were investigated in sera from PCa patients and tumour tissues derived from nude mice using immunohistochemical analysis and enzyme-linked immunosorbent assays (ELISA). Cell mobility and mineralization were quantified using BioStation CT and Osteolmage assay. The relative cistrome was investigated in advanced PCa cells by standard transcriptional analyses, including the luciferase reporter response, site-directed mutagenesis, and chromatin immunoprecipitation (ChIP) assay. PCa cell-initiated tumour formation, expansion, and bone metastasis were validated in mice using multiple approaches, including orthotopic, intraskeletal, and caudal arterial implantation models. RESULTS IL-8 and S100A4 correlated with patient Gleason scores and bone metastasis. RelB upregulated IL-8, facilitating androgen receptor (AR)-independent growth. RelB-Sp1 interaction enhanced epithelial-mesenchymal transition (EMT) by activating Snail and Twist. RelB-NFAT1c super-enhancer upregulated S100A4 in the organization of the cytoskeleton and bone metastasis. The RelB-IL-8-S100A4 signalling axis was confirmed to promote osteolytic metastasis in nude mice. CONCLUSION RelB-IL-8 reciprocally promoted EMT by activating inflammatory signalling and inactivating AR signalling. IL-8 is essential for provoking PCa metastasis but insufficient to drive bone metastasis. IL-8-S100A4 cooperation was necessary for metastatic cells to target the bone. HIGHLIGHTS RelB activates inflammatory signalling by upregulating IL-8 and suppressing AR. RelB upregulates S100A4 by cooperating with NFATC1. IL-8 boosts EMT by activating Snail 1 and Twist 1, and S100A4 exacerbates osteolytic metastasis via calcium consumption. RelB harnesses IL-8 and S100A4 to drive PCa osteolytic metastasis.
Collapse
|
5
|
Le Voyer T, Maglorius Renkilaraj MRL, Moriya K, Pérez Lorenzo M, Nguyen T, Gao L, Rubin T, Cederholm A, Ogishi M, Arango-Franco CA, Béziat V, Lévy R, Migaud M, Rapaport F, Itan Y, Deenick EK, Cortese I, Lisco A, Boztug K, Abel L, Boisson-Dupuis S, Boisson B, Frosk P, Ma CS, Landegren N, Celmeli F, Casanova JL, Tangye SG, Puel A. Inherited human RelB deficiency impairs innate and adaptive immunity to infection. Proc Natl Acad Sci U S A 2024; 121:e2321794121. [PMID: 39231201 PMCID: PMC11406260 DOI: 10.1073/pnas.2321794121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Accepted: 06/24/2024] [Indexed: 09/06/2024] Open
Abstract
We report two unrelated adults with homozygous (P1) or compound heterozygous (P2) private loss-of-function variants of V-Rel Reticuloendotheliosis Viral Oncogene Homolog B (RELB). The resulting deficiency of functional RelB impairs the induction of NFKB2 mRNA and NF-κB2 (p100/p52) protein by lymphotoxin in the fibroblasts of the patients. These defects are rescued by transduction with wild-type RELB complementary DNA (cDNA). By contrast, the response of RelB-deficient fibroblasts to Tumor Necrosis Factor (TNF) or IL-1β via the canonical NF-κB pathway remains intact. P1 and P2 have low proportions of naïve CD4+ and CD8+ T cells and of memory B cells. Moreover, their naïve B cells cannot differentiate into immunoglobulin G (IgG)- or immunoglobulin A (IgA)-secreting cells in response to CD40L/IL-21, and the development of IL-17A/F-producing T cells is strongly impaired in vitro. Finally, the patients produce neutralizing autoantibodies against type I interferons (IFNs), even after hematopoietic stem cell transplantation, attesting to a persistent dysfunction of thymic epithelial cells in T cell selection and central tolerance to some autoantigens. Thus, inherited human RelB deficiency disrupts the alternative NF-κB pathway, underlying a T- and B cell immunodeficiency, which, together with neutralizing autoantibodies against type I IFNs, confers a predisposition to viral, bacterial, and fungal infections.
Collapse
|
6
|
Deka A, Kumar N, Basu S, Chawla M, Bhattacharya N, Ali SA, Bhawna, Madan U, Kumar S, Das B, Sengupta D, Awasthi A, Basak S. Non-canonical NF-κB signaling limits the tolerogenic β-catenin-Raldh2 axis in gut dendritic cells to exacerbate intestinal pathologies. EMBO J 2024; 43:3895-3915. [PMID: 39060515 PMCID: PMC11405688 DOI: 10.1038/s44318-024-00182-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2024] [Revised: 07/12/2024] [Accepted: 07/12/2024] [Indexed: 07/28/2024] Open
Abstract
Dendritic cell (DC) dysfunction is known to exacerbate intestinal pathologies, but the mechanisms compromising DC-mediated immune regulation in this context remain unclear. Here, we show that intestinal dendritic cells from a mouse model of experimental colitis exhibit significant levels of noncanonical NF-κB signaling, which activates the RelB:p52 heterodimer. Genetic inactivation of this pathway in DCs alleviates intestinal pathologies in mice suffering from colitis. Deficiency of RelB:p52 diminishes transcription of Axin1, a critical component of the β-catenin destruction complex, reinforcing β-catenin-dependent expression of Raldh2, which imparts tolerogenic DC attributes by promoting retinoic acid synthesis. DC-specific impairment of noncanonical NF-κB signaling leads to increased colonic numbers of Tregs and IgA+ B cells, which promote luminal IgA production and foster eubiosis. Experimentally introduced β-catenin haploinsufficiency in DCs with deficient noncanonical NF-κB signaling moderates Raldh2 activity, reinstating colitogenic sensitivity in mice. Finally, inflammatory bowel-disease patients also display a deleterious noncanonical NF-κB signaling signature in intestinal DCs. In sum, we establish how noncanonical NF-κB signaling in dendritic cells can subvert retinoic acid synthesis to fuel intestinal inflammation.
Collapse
|
7
|
Lin Y, Liu M, Deng P, Zhang J. TET1 mediated m5C modification of RelB aggravates cerebral ischemia/reperfusion-induced neuroinflammation through regulating microglia polarization. Cell Signal 2024; 120:111210. [PMID: 38705503 DOI: 10.1016/j.cellsig.2024.111210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2024] [Revised: 04/11/2024] [Accepted: 05/02/2024] [Indexed: 05/07/2024]
Abstract
Microglia mediated neuroinflammation is one of the major contributors to brain damage in cerebral ischemia reperfusion injury (CI/RI). Recently, RNA modification was found to contribute to the regulation of microglia polarization and the subsequent development of cerebral I/R neuroinflammation. Herein, we investigated the effect and mechanism of m5C RNA modification in the microglia induced CI/RI neuroinflammation. We found that the m5C RNA modification levels decreased in the primary microglia isolated from a mouse model of intraluminal middle cerebral artery occlusion/reperfusion (MCAO/R) and the BV2 microglial cells subjected to oxygen-glucose deprivation and reoxygenation (OGD/R), and this change was accompanied by an increase in the M1/M2 polarization ratio. Furthermore, the expression of m5C demethylase TET1 in microglia increased, which promoted M1 polarization but impeded M2 polarization. Mechanistically, the higher TET1 expression decreased the m5C modification level of RelB and enhanced its mRNA stability, which subsequently increased the M1/M2 polarization ratio. In conclusion, this study provides insight into the role of m5C RNA modification in the pathogenesis of cerebral I/R neuroinflammation and may deepen our understanding on clinical therapy targeting the TET1-RelB axis.
Collapse
|
8
|
Scherr AL, Nader L, Xu K, Elssner C, Ridder DA, Nichetti F, Mastel M, Fritzsche S, Kelmendi E, Schmitt N, Hoffmeister-Wittmann P, Weiler SME, Korell F, Albrecht T, Schwab M, Isele H, Kessler A, Hüllein J, Seretny A, Ye L, Urbanik T, Welte S, Leblond AL, Heilig CE, Rahbari M, Ali A, Gallage S, Lenoir B, Wilhelm N, Gärtner U, Ogrodnik SJ, Springfeld C, Tschaharganeh D, Fröhling S, Longerich T, Schulze-Bergkamen H, Jäger D, Brandl L, Schirmacher P, Straub BK, Weber A, De Toni EN, Goeppert B, Heikenwalder M, Jackstadt R, Roessler S, Breuhahn K, Köhler BC. Etiology-independent activation of the LTβ-LTβR-RELB axis drives aggressiveness and predicts poor prognosis in HCC. Hepatology 2024; 80:278-294. [PMID: 37916976 DOI: 10.1097/hep.0000000000000657] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Accepted: 09/21/2023] [Indexed: 11/03/2023]
Abstract
BACKGROUND AND AIMS HCC is the most common primary liver tumor, with an increasing incidence worldwide. HCC is a heterogeneous malignancy and usually develops in a chronically injured liver. The NF-κB signaling network consists of a canonical and a noncanonical branch. Activation of canonical NF-κB in HCC is documented. However, a functional and clinically relevant role of noncanonical NF-κB and its downstream effectors is not established. APPROACH AND RESULTS Four human HCC cohorts (total n = 1462) and 4 mouse HCC models were assessed for expression and localization of NF-κB signaling components and activating ligands. In vitro , NF-κB signaling, proliferation, and cell death were measured, proving a pro-proliferative role of v-rel avian reticuloendotheliosis viral oncogene homolog B (RELB) activated by means of NF-κB-inducing kinase. In vivo , lymphotoxin beta was identified as the predominant inducer of RELB activation. Importantly, hepatocyte-specific RELB knockout in a murine HCC model led to a lower incidence compared to controls and lower maximal tumor diameters. In silico , RELB activity and RELB-directed transcriptomics were validated on the The Cancer Genome Atlas HCC cohort using inferred protein activity and Gene Set Enrichment Analysis. In RELB-active HCC, pathways mediating proliferation were significantly activated. In contrast to v-rel avian reticuloendotheliosis viral oncogene homolog A, nuclear enrichment of noncanonical RELB expression identified patients with a poor prognosis in an etiology-independent manner. Moreover, RELB activation was associated with malignant features metastasis and recurrence. CONCLUSIONS This study demonstrates a prognostically relevant, etiology-independent, and cross-species consistent activation of a lymphotoxin beta/LTβR/RELB axis in hepatocarcinogenesis. These observations may harbor broad implications for HCC, including possible clinical exploitation.
Collapse
|
9
|
Chen Q, Muñoz AR, Korchagina AA, Shou Y, Vallecer J, Todd AW, Shein SA, Tumanov AV, Koroleva E. LTβR-RelB signaling in intestinal epithelial cells protects from chemotherapy-induced mucosal damage. Front Immunol 2024; 15:1388496. [PMID: 38873613 PMCID: PMC11169669 DOI: 10.3389/fimmu.2024.1388496] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2024] [Accepted: 05/01/2024] [Indexed: 06/15/2024] Open
Abstract
The intricate immune mechanisms governing mucosal healing following intestinal damage induced by cytotoxic drugs remain poorly understood. The goal of this study was to investigate the role of lymphotoxin beta receptor (LTβR) signaling in chemotherapy-induced intestinal damage. LTβR deficient mice exhibited heightened body weight loss, exacerbated intestinal pathology, increased proinflammatory cytokine expression, reduced IL-22 expression, and proliferation of intestinal epithelial cells following methotrexate (MTX) treatment. Furthermore, LTβR-/-IL-22-/- mice succumbed to MTX treatment, suggesting that LTβR- and IL-22- dependent pathways jointly promote mucosal repair. Although both LTβR ligands LIGHT and LTβ were upregulated in the intestine early after MTX treatment, LIGHT-/- mice, but not LTβ-/- mice, displayed exacerbated disease. Further, we revealed the critical role of T cells in mucosal repair as T cell-deficient mice failed to upregulate intestinal LIGHT expression and exhibited increased body weight loss and intestinal pathology. Analysis of mice with conditional inactivation of LTβR revealed that LTβR signaling in intestinal epithelial cells, but not in Lgr5+ intestinal stem cells, macrophages or dendritic cells was critical for mucosal repair. Furthermore, inactivation of the non-canonical NF-kB pathway member RelB in intestinal epithelial cells promoted MTX-induced disease. Based on these results, we propose a model wherein LIGHT produced by T cells activates LTβR-RelB signaling in intestinal epithelial cells to facilitate mucosal repair following chemotherapy treatment.
Collapse
|
10
|
Ulrich C, Canim Z, Herberger E, Girndt M, Fiedler R. Inflammation in Hypervolemic Hemodialysis Patients: The Roles of RelB and Caspase-4. Int J Mol Sci 2023; 24:17550. [PMID: 38139378 PMCID: PMC10743509 DOI: 10.3390/ijms242417550] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Revised: 12/05/2023] [Accepted: 12/13/2023] [Indexed: 12/24/2023] Open
Abstract
Hypervolemia is associated with inflammation in hemodialysis (HD) patients. How hypervolemia triggers inflammation is not entirely known. We initiated a cross-sectional study enrolling 40 hemodialysis patients who were categorized into normovolemic (N; 23) and hypervolemic (H; 17) groups by bioimpedance measurement. A caspase activity assay in combination with a specific caspase-4 inhibitor was used to detect caspase-4 activity in isolated peripheral blood mononuclear cells (PBMCs). Transcription factors RelA (pS529) and RelB (pS552) were analyzed by phospho-flow cytometry. Serum endotoxins were detected by an amebocyte lysate-based assay, and IL-6 (interleukin-6) and TNF-α (Tumor necrosis factor-α) gene expression were detected using the ELISA technique. Hypervolemic patients were older, more frequently had diabetes and showed increased CRP and IL-6 levels. Caspase-4 activity, which is linked to intracellular endotoxin detection, was significantly elevated in H patients. While the frequency of RelA-expressing immune cells and the expression density in these cells did not differ, the monocytic frequency of cells positively stained for RelB (pS552) was significantly decreased in H patients. Increased caspase-4 activity in H patients may indicate a cause of inflammation in H patients. The post-translational modification of RelB (pS552) is linked to downregulation of NF-kB activity and may indicate the resolution of inflammation, which is more distinct in N patients compared to H patients. Therefore, both higher inflammatory loads and lower inflammatory resolution capacities are characteristics of H patients.
Collapse
|
11
|
Navarro HI, Liu Y, Fraser A, Lefaudeux D, Chia JJ, Vong L, Roifman CM, Hoffmann A. RelB-deficient autoinflammatory pathology presents as interferonopathy, but in mice is interferon-independent. J Allergy Clin Immunol 2023; 152:1261-1272. [PMID: 37460023 PMCID: PMC10858800 DOI: 10.1016/j.jaci.2023.06.024] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Revised: 05/19/2023] [Accepted: 06/13/2023] [Indexed: 08/06/2023]
Abstract
BACKGROUND Autoimmune diseases are leading causes of ill health and morbidity and have diverse etiology. Two signaling pathways are key drivers of autoimmune pathology, interferon and nuclear factor-κB (NF-κB)/RelA, defining the 2 broad labels of interferonopathies and relopathies. Prior work has established that genetic loss of function of the NF-κB subunit RelB leads to autoimmune and inflammatory pathology in mice and humans. OBJECTIVE We sought to characterize RelB-deficient autoimmunity by unbiased profiling of the responses of immune sentinel cells to stimulus and to determine the functional role of dysregulated gene programs in the RelB-deficient pathology. METHODS Transcriptomic profiling was performed on fibroblasts and dendritic cells derived from patients with RelB deficiency and knockout mice, and transcriptomic responses and pathology were assessed in mice deficient in both RelB and the type I interferon receptor. RESULTS We found that loss of RelB in patient-derived fibroblasts and mouse myeloid cells results in elevated induction of hundreds of interferon-stimulated genes. Removing hyperexpression of the interferon-stimulated gene program did not ameliorate the autoimmune pathology of RelB knockout mice. Instead, we found that RelB suppresses a different set of inflammatory response genes in a manner that is independent of interferon signaling but associated with NF-κB binding motifs. CONCLUSION Although transcriptomic profiling would describe RelB-deficient autoimmune disease as an interferonopathy, the genetic evidence indicates that the pathology in mice is interferon-independent.
Collapse
|
12
|
Sharfe N, Dalal I, Naghdi Z, Lefaudeux D, Vong L, Dadi H, Navarro H, Tasher D, Ovadia A, Zangen T, Ater D, Ngan B, Hoffmann A, Roifman CM. NFκB pathway dysregulation due to reduced RelB expression leads to severe autoimmune disorders and declining immunity. J Autoimmun 2023; 137:102946. [PMID: 36402602 DOI: 10.1016/j.jaut.2022.102946] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Accepted: 10/23/2022] [Indexed: 11/18/2022]
Abstract
BACKGROUND Genetic aberrations in the NFκB pathway lead to primary immunodeficiencies with various degrees of severity. We previously demonstrated that complete ablation of the RelB transcription factor, a key component of the alternative pathway, results in an early manifested combined immunodeficiency requiring stem cell transplantation. OBJECTIVE To study the molecular basis of a progressive severe autoimmunity and immunodeficiency in three patients. METHODS Whole exome sequencing was performed to identify the genetic defect. Molecular and cellular techniques were utilized to assess the variant impact on NFκB signaling, canonical and alternative pathway crosstalk, as well as the resultant effects on immune function. RESULTS Patients presented with multiple autoimmune progressive severe manifestations encompassing the liver, gut, lung, and skin, becoming debilitating in the second decade of life. This was accompanied by a deterioration of the immune system, demonstrating an age-related decline in naïve T cells and responses to mitogens, accompanied by a gradual loss of all circulating CD19+ cells. Whole exome sequencing identified a novel homozygous c. C1091T (P364L) transition in RELB. The P364L RelB protein was unstable, with extremely low expression, but retained some function and could be transiently and partially upregulated following Toll-like receptor stimulation. Stimulation of P364L patient fibroblasts resulted in a marked rise in a cluster of pro-inflammatory hyper-expressed transcripts consistent with the removal of RelB inhibitory effect on RelA function. This is likely the main driver of autoimmune manifestations in these patients. CONCLUSION Incomplete loss of RelB provided a unique opportunity to gain insights into NFκB's pathway interactions as well as the pathogenesis of autoimmunity. The P364L RelB mutation leads to gradual decline in immune function with progression of severe debilitating autoimmunity.
Collapse
|
13
|
Kuhn LB, Valentin S, Stojanovic K, Strobl DC, Babushku T, Wang Y, Rambold U, Scheffler L, Grath S, John-Robbert D, Blum H, Feuchtinger A, Blutke A, Weih F, Kitamura D, Rad R, Strobl LJ, Zimber-Strobl U. RelB contributes to the survival, migration and lymphomagenesis of B cells with constitutively active CD40 signaling. Front Immunol 2022; 13:913275. [PMID: 36110848 PMCID: PMC9468873 DOI: 10.3389/fimmu.2022.913275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Accepted: 08/04/2022] [Indexed: 11/14/2022] Open
Abstract
Activation of CD40-signaling contributes to the initiation, progression and drug resistance of B cell lymphomas. We contributed to this knowledge by showing that constitutive CD40-signaling in B cells induces B cell hyperplasia and finally B cell lymphoma development in transgenic mice. CD40 activates, among others, the non-canonical NF-ĸB signaling, which is constitutively activated in several human B cell lymphomas and is therefore presumed to contribute to lymphopathogenesis. This prompted us to study the regulatory role of the non-canonical NF-ĸB transcription factor RelB in lymphomagenesis. To this end, we crossed mice expressing a constitutively active CD40 receptor in B cells with conditional RelB-KO mice. Ablation of RelB attenuated pre-malignant B cell expansion, and resulted in an impaired survival and activation of long-term CD40-stimulated B cells. Furthermore, we found that hyperactivation of non-canonical NF-кB signaling enhances the retention of B cells in the follicles of secondary lymphoid organs. RNA-Seq-analysis revealed that several genes involved in B-cell migration, survival, proliferation and cytokine signaling govern the transcriptional differences modulated by the ablation of RelB in long-term CD40-stimulated B cells. Inactivation of RelB did not abrogate lymphoma development. However, lymphomas occurred with a lower incidence and had a longer latency period. In summary, our data suggest that RelB, although it is not strictly required for malignant transformation, accelerates the lymphomagenesis of long-term CD40-stimulated B cells by regulating genes involved in migration, survival and cytokine signaling.
Collapse
|
14
|
Chaiswing L, Xu F, Zhao Y, Thorson J, Wang C, He D, Lu J, Ellingson SR, Zhong W, Meyer K, Luo W, St. Clair W, Clair DS. The RelB-BLNK Axis Determines Cellular Response to a Novel Redox-Active Agent Betamethasone during Radiation Therapy in Prostate Cancer. Int J Mol Sci 2022; 23:ijms23126409. [PMID: 35742868 PMCID: PMC9223669 DOI: 10.3390/ijms23126409] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 06/01/2022] [Accepted: 06/04/2022] [Indexed: 11/16/2022] Open
Abstract
Aberrant levels of reactive oxygen species (ROS) are potential mechanisms that contribute to both cancer therapy efficacy and the side effects of cancer treatment. Upregulation of the non-canonical redox-sensitive NF-kB family member, RelB, confers radioresistance in prostate cancer (PCa). We screened FDA-approved compounds and identified betamethasone (BET) as a drug that increases hydrogen peroxide levels in vitro and protects non-PCa tissues/cells while also enhancing radiation killing of PCa tissues/cells, both in vitro and in vivo. Significantly, BET increases ROS levels and exerts different effects on RelB expression in normal cells and PCa cells. BET induces protein expression of RelB and RelB target genes, including the primary antioxidant enzyme, manganese superoxide dismutase (MnSOD), in normal cells, while it suppresses protein expression of RelB and MnSOD in LNCaP cells and PC3 cells. RNA sequencing analysis identifies B-cell linker protein (BLNK) as a novel RelB complementary partner that BET differentially regulates in normal cells and PCa cells. RelB and BLNK are upregulated and correlate with the aggressiveness of PCa in human samples. The RelB-BLNK axis translocates to the nuclear compartment to activate MnSOD protein expression. BET promotes the RelB-BLNK axis in normal cells but suppresses the RelB-BLNK axis in PCa cells. Targeted disruptions of RelB-BLNK expressions mitigate the radioprotective effect of BET on normal cells and the radiosensitizing effect of BET on PCa cells. Our study identified a novel RelB complementary partner and reveals a complex redox-mediated mechanism showing that the RelB-BLNK axis, at least in part, triggers differential responses to the redox-active agent BET by stimulating adaptive responses in normal cells but pushing PCa cells into oxidative stress overload.
Collapse
|
15
|
Moy RH, Nguyen A, Loo JM, Yamaguchi N, Kajba CM, Santhanam B, Ostendorf BN, Wu YG, Tavazoie S, Tavazoie SF. Functional genetic screen identifies ITPR3/calcium/RELB axis as a driver of colorectal cancer metastatic liver colonization. Dev Cell 2022; 57:1146-1159.e7. [PMID: 35487218 PMCID: PMC9446818 DOI: 10.1016/j.devcel.2022.04.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2021] [Revised: 03/02/2022] [Accepted: 04/06/2022] [Indexed: 11/29/2022]
Abstract
Metastatic colonization is the primary cause of death from colorectal cancer (CRC). We employed genome-scale in vivo short hairpin RNA (shRNA) screening and validation to identify 26 promoters of CRC liver colonization. Among these genes, we identified a cluster that contains multiple targetable genes, including ITPR3, which promoted liver-metastatic colonization and elicited similar downstream gene expression programs. ITPR3 is a caffeine-sensitive inositol 1,4,5-triphosphate (IP3) receptor that releases calcium from the endoplasmic reticulum and enhanced metastatic colonization by inducing expression of RELB, a transcription factor that is associated with non-canonical NF-κB signaling. Genetic, cell biological, pharmacologic, and clinical association studies revealed that ITPR3 and RELB drive CRC colony formation by promoting cell survival upon substratum detachment or hypoxic exposure. RELB was sufficient to drive colonization downstream of ITPR3. Our findings implicate the ITPR3/calcium/RELB axis in CRC metastatic colony formation and uncover multiple clinico-pathologically associated targetable proteins as drivers of CRC metastatic colonization.
Collapse
|
16
|
Wang M, Zhang Y, Xu Z, Qian P, Sun W, Wang X, Jian Z, Xia T, Xu Y, Tang J. RelB sustains endocrine resistant malignancy: an insight of noncanonical NF-κB pathway into breast Cancer progression. Cell Commun Signal 2020; 18:128. [PMID: 32807176 PMCID: PMC7430126 DOI: 10.1186/s12964-020-00613-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Accepted: 06/23/2020] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND The activation of the NF-κB pathway plays a crucial role in the progression of breast cancer (BCa) and also involved in endocrine therapy resistance. On the contrary to the canonical NF-κB pathway, the effect of the noncanonical NF-κB pathway in BCa progression remains elusive. METHODS BCa tumor tissues and the corresponding cell lines were examined to determine the correlation between RelB and the aggressiveness of BCa. RelB was manipulated in BCa cells to examine whether RelB promotes cell proliferation and motility by quantitation of apoptosis, cell cycle, migration, and invasion. RNA-Seq was performed to identify the critical RelB-regulated genes involved in BCa metastasis. Particularly, RelB-regulated MMP1 transcription was verified using luciferase reporter and ChIP assay. Subsequently, the effect of RelB on BCa progression was further validated using BCa mice xenograft models. RESULTS RelB uniquely expresses at a high level in aggressive BCa tissues, particularly in triple-negative breast cancer (TNBC). RelB promotes BCa cell proliferation through increasing G1/S transition and/or decreasing apoptosis by upregulation of Cyclin D1 and Bcl-2. Additionally, RelB enhances cell mobility by activating EMT. Importantly, RelB upregulates bone metastatic protein MMP1 expression through binding to an NF-κB enhancer element located at the 5'-flanking region. Accordingly, in vivo functional validation confirmed that RelB deficiency impairs tumor growth in nude mice and inhibits lung metastasis in SCID mice. Video abstract.
Collapse
|
17
|
Gamboa-Cedeño AM, Castillo M, Xiao W, Waldmann TA, Ranuncolo SM. Alternative and canonical NF-kB pathways DNA-binding hierarchies networks define Hodgkin lymphoma and Non-Hodgkin diffuse large B Cell lymphoma respectively. J Cancer Res Clin Oncol 2019; 145:1437-1448. [PMID: 30941572 PMCID: PMC8317045 DOI: 10.1007/s00432-019-02909-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Accepted: 03/25/2019] [Indexed: 12/22/2022]
Abstract
PURPOSE Despite considerable evidence that supports the NF-kB role in the immune system and lymphomagenesis, it is unclear whether specific NF-kB dimers control a particular set of genes that account for their biological functions. Our previous work showed that Hodgkin Lymphoma (HL) is unique, among germinal center (GC)-derived lymphomas, with respect to its dependency on Rel-B to survive. In contrast, diffuse large B-Cell lymphoma (DLBCL) including both Activated B-Cell-Like and Germinal Center B-Cell-Like, requires cREL and Rel-A to survive and it is not affected by Rel-B depletion. These findings highlighted the activity of specific NF-kB subunits in different GC-derived lymphomas. METHODS Sequenced chromatin immunoprecipitated DNA fragments (ChIP-Seq) analysis revealed an extensive NF-kB DNA-binding network in DLBCL and HL. The ChIP-Seq data was merged with microarray analysis following the Rel-A, Rel-B or cRel knockdown to determine effectively regulated genes. RESULTS Downstream target analysis showed enrichment for cell cycle control, among other signatures. Rel-B and cRel controlled different genes within the same signature in HL and DLBCL, respectively. BCL2 was exclusively controlled by Rel-B in HL. Both mRNA and protein levels decreased following Rel-B depletion meanwhile there was no change upon cRel knock-down. BCL2 exogenous expression partially rescued the death induced by decreased Rel-B in HL cells. CONCLUSION The Rel-B hierarchical network defined HL and the cRel hierarchical network characterized DLBCL. Each Rel member performs specific functions in distinct GC-derived lymphomas. This result should be considered for the development of targeted therapies that are aimed to selectively inhibit individual NF-kB dimers.
Collapse
|
18
|
Ishihara Y, Kado SY, Hoeper C, Harel S, Vogel CFA. Role of NF-kB RelB in Aryl Hydrocarbon Receptor-Mediated Ligand Specific Effects. Int J Mol Sci 2019; 20:E2652. [PMID: 31151139 PMCID: PMC6600526 DOI: 10.3390/ijms20112652] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2019] [Revised: 05/24/2019] [Accepted: 05/26/2019] [Indexed: 01/21/2023] Open
Abstract
Here, we investigate the role of RelB in the regulation of genes which were identified to be induced in an aryl hydrocarbon receptor (AhR)-dependent manner and critically involved in regulation of immune responses. We analyzed the expression of genes of the AhR gene battery, cytokines, and immune regulatory enzymes in bone marrow-derived macrophages (BMM) and thymus of B6 wildtype (wt) mice and RelB knockout (RelB-/-) mice after treatment with various AhR ligands. The 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-induced expression of indoleamine 2,3-dioxygenase 1 (IDO1) and IDO2 was significantly repressed in thymus of RelB-/- mice but not in BMM derived from RelB-/- mice. Interestingly, the induced and basal expression of the cytokines interleukin (IL)-17A, IL-22, and CCL20 required the functional expression of RelB. The RelB-dependent expression of CCL20 was induced by the AhR ligands TCDD and 6-formylindolo[3,2-b]carbazole (FICZ), whereas indole-3-carbinol (I3C) suppressed CCL20 in lipopolysaccharide (LPS)-activated wt BMM. The LPS-induced expression of IL-6 and IL-10 was enhanced by TCDD and FICZ, whereas I3C significantly suppressed these cytokines in BMM. The exposure to FICZ led to higher increases of IL-17A and IL-22 mRNA compared to the effect of TCDD or I3C in thymus of wt mice. On the other hand, TCDD was the strongest inducer of CYP1A1, AhR Repressor (AhRR), and IDO2. In summary, these findings provide evidence for the important role of RelB in the transcriptional regulation of cytokines and enzymes induced by AhR ligands.
Collapse
|
19
|
Hua F, Li CH, Gao YC, Li J, Meng F. Molecular mechanism and role of NF-κB in the early diagnosis of cervical cancer. JOURNAL OF B.U.ON. : OFFICIAL JOURNAL OF THE BALKAN UNION OF ONCOLOGY 2019; 24:720-728. [PMID: 31128029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
PURPOSE The purpose of this study was to find out the activity and molecular mechanism of NF-kB subunits in cervical cancer which in turn were used as a molecular marker in diagnosing cancer progression. METHODS Different cervical cancer biopsies were obtained from patients after obtaining proper written consent and approval, which were subjected to immunohistochemistry. Performed were Western blot analysis and electrophoretic mobility shift assays. RESULTS Immunohistochemical analysis of low-grade, high-grade and squamous cell carcinoma (SCC) (stage IIIA, IIIB and IV) showed low to high nuclear expression of p52/RelB compared with p50/RelA, whereas in normal cells, c-Rel was expressed in the cytosol. p52/RelB expression was further validated by Western blot analysis. The binding ability of NF-κB to p52/RelB was increased during the progression of cervical cancer. All cervical carcinoma biopsies showed increased expression of p50/RelA and p52/RelB, but the p52/RelB NF-κB protein complex showed elevated nuclear expression and binding ability, indicating a pathway other than the classical pathway. The non-canonical NF-κB pathway also played an important role in cervical cancer progression by activating the p52/RelB NF-κB complex. CONCLUSIONS This study provides a new approach for diagnosing, and establishing an appropriate treatment against cervical cancer progression.
Collapse
|
20
|
Das R, Coupar J, Clavijo PE, Saleh A, Cheng TF, Yang X, Chen J, VanWaes C, Chen Z. Lymphotoxin-β receptor-NIK signaling induces alternative RELB/NF-κB2 activation to promote metastatic gene expression and cell migration in head and neck cancer. Mol Carcinog 2019; 58:411-425. [PMID: 30488488 PMCID: PMC7066987 DOI: 10.1002/mc.22938] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Revised: 10/27/2018] [Accepted: 10/29/2018] [Indexed: 01/21/2023]
Abstract
Head and neck squamous cell carcinomas (HNSCC) preferentially spread to regional cervical tissues and lymph nodes. Here, we hypothesized that lymphotoxin-β (LTβ), receptor LTβR, and NF-κB-inducing kinase (NIK), promote the aberrant activation of alternative NF-κB2/RELB pathway and genes, that enhance migration and invasion of HNSCC. Genomic and expression alterations of the alternative NF-kB pathway were examined in 279 HNSCC tumors from The Cancer Genome Atlas (TCGA) and a panel of HNSCC lines. LTβR is amplified or overexpressed in HNSCC of the larynx or oral cavity, while LTβ, NIK, and RELB are overexpressed in cancers arising within lymphoid oropharyngeal and tonsillar sites. Similarly, subsets of HNSCC lines displayed overexpression of LTβR, NIK, and RELB proteins. Recombinant LTβ, and siRNA depletion of endogenous LTβR and NIK, modulated expression of LTβR, NIK, and nuclear translocation of NF-κB2(p52)/RELB as well as functional NF-κB promoter reporter activity. Treatment with a NIK inhibitor (1,3[2H,4H]-Iso-Quinoline Dione) reduced the protein expression of NIK and NF-κB2(p52)/RELB, and blocked LTβ induced nuclear translocation of RELB. NIK and RELB siRNA knockdown or NIK inhibitor slowed HNSCC migration or invation in vitro. LTβ-induces expression of migration and metastasis related genes, including hepatocyte growth/scatter factor receptor MET. Knockdown of NIK or MET similarly inhibited the migration of HNSCC cell lines. This may help explain why HNSCC preferentially migrate to local lymph nodes, where LTβ is expressed. Our findings show that LTβ/LTβR promotes activation of the alternative NIK-NF-κB2/RELB pathway to enhance MET-mediated cell migration in HNSCC, which could be potential therapeutic targets in HNSCC.
Collapse
|
21
|
Bobardt M, Kuo J, Chatterji U, Chanda S, Little SJ, Wiedemann N, Vuagniaux G, Gallay PA. The inhibitor apoptosis protein antagonist Debio 1143 Is an attractive HIV-1 latency reversal candidate. PLoS One 2019; 14:e0211746. [PMID: 30716099 PMCID: PMC6361451 DOI: 10.1371/journal.pone.0211746] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Accepted: 01/18/2019] [Indexed: 01/08/2023] Open
Abstract
Antiretroviral therapy (ART) suppresses HIV replication, but does not cure the infection because replication-competent virus persists within latently infected CD4+ T cells throughout years of therapy. These reservoirs contain integrated HIV-1 genomes and can resupply active virus. Thus, the development of strategies to eliminate the reservoir of latently infected cells is a research priority of global significance. In this study, we tested efficacy of a new inhibitor of apoptosis protein antagonist (IAPa) called Debio 1143 at reversing HIV latency and investigated its mechanisms of action. Debio 1143 activates HIV transcription via NF-kB signaling by degrading the ubiquitin ligase baculoviral IAP repeat-containing 2 (BIRC2), a repressor of the non-canonical NF-kB pathway. Debio 1143-induced BIRC2 degradation results in the accumulation of NF-κB-inducing kinase (NIK) and proteolytic cleavage of p100 into p52, leading to nuclear translocation of p52 and RELB. Debio 1143 greatly enhances the binding of RELB to the HIV-1 LTR. These data indicate that Debio 1143 activates the non-canonical NF-kB signaling pathway by promoting the binding of RELB:p52 complexes to the HIV-1 LTR, resulting in the activation of the LTR-dependent HIV-1 transcription. Importantly, Debio 1143 reverses viral latency in HIV-1 latent T cell lines. Using knockdown (siRNA BIRC2), knockout (CRIPSR NIK) and proteasome machinery neutralization (MG132) approaches, we found that Debio 1143-mediated HIV latency reversal is BIRC2 degradation- and NIK stabilization-dependent. Debio 1143 also reverses HIV-1 latency in resting CD4+ T cells derived from ART-treated patients or HIV-1-infected humanized mice under ART. Interestingly, daily oral administration of Debio 1143 in cancer patients at well-tolerated doses elicited BIRC2 target engagement in PBMCs and induced a moderate increase in cytokines and chemokines mechanistically related to NF-kB signaling. In conclusion, we provide strong evidences that the IAPa Debio 1143, by initially activating the non-canonical NF-kB signaling and subsequently reactivating HIV-1 transcription, represents a new attractive viral latency reversal agent (LRA).
Collapse
|
22
|
Gonzalez-Torres C, Gaytan-Cervantes J, Vazquez-Santillan K, Mandujano-Tinoco EA, Ceballos-Cancino G, Garcia-Venzor A, Zampedri C, Sanchez-Maldonado P, Mojica-Espinosa R, Jimenez-Hernandez LE, Maldonado V. NF-κB Participates in the Stem Cell Phenotype of Ovarian Cancer Cells. Arch Med Res 2017; 48:343-351. [PMID: 28886875 DOI: 10.1016/j.arcmed.2017.08.001] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2016] [Accepted: 08/24/2017] [Indexed: 12/11/2022]
Abstract
BACKGROUND NF-κB is a transcription factor involved in cancer stem cells maintenance of many tumors. Little is known about the specific stem-associated upstream regulators of this pathway in ovarian cancer. The Aim of the study was to analyze the role of the canonical and non-canonical NF-κB pathways in stem cells of ovarian cancer cell lines. METHODS Stem cells were isolated using sorting cytometry. Western blot and RT-PCR were used to quantify protein and messenger RNA levels. Loss and gain of function assays were performed using siRNAs and dominant-negative proteins, respectively. NF-κB binding activity was measured with a reporter gene assay. The stem phenotype was estimated with clonogenic assays using soft agar, colony formation, ovospheres formation and in vivo tumorigenicity assays. RESULTS The CD44+ subpopulation of SKOV3 ovarian cancer cell line presented higher mRNA levels of key stemness genes, an increased tumorigenic capacity and higher expression of the RelA, RelB and IKKα. When the canonical pathway was inhibited by means of a dominant-negative version of IkBα, the stem cell population was reduced, as shown by a reduced CD44+ subpopulation, a decrease in the expression of the stemness genes and a reduction of the stem phenotype. In addition, IKKα, the main upstream non-canonical kinase, was highly expressed in the CSC population. Accordingly, when IKKα was inhibited using shRNAs, the expression of the stemness genes was reduced. CONCLUSIONS This report is the first to show the importance of several elements of both NF-κB pathway in maintaining the ovarian cancer stem cell population.
Collapse
|
23
|
Iu M, Zago M, Rico de Souza A, Bouttier M, Pareek S, White JH, Hamid Q, Eidelman DH, Baglole CJ. RelB attenuates cigarette smoke extract-induced apoptosis in association with transcriptional regulation of the aryl hydrocarbon receptor. Free Radic Biol Med 2017; 108:19-31. [PMID: 28254546 DOI: 10.1016/j.freeradbiomed.2017.02.045] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/07/2016] [Revised: 02/22/2017] [Accepted: 02/23/2017] [Indexed: 10/20/2022]
Abstract
Chronic obstructive pulmonary disease (COPD) is a chronic and prevalent respiratory disease caused primarily by long term inhalation of cigarette smoke. A major hallmark of COPD is elevated apoptosis of structural lung cells including fibroblasts. The NF-κB member RelB may suppress apoptosis in response to cigarette smoke, but its role in lung cell survival is not known. RelB may act as a pro-survival factor by controlling the expression of superoxide dismutase 2 (SOD2). SOD2 is also regulated by the aryl hydrocarbon receptor (AhR), a ligand-activated transcription factor that suppresses cigarette smoke-induced apoptosis. As the AhR is also a binding partner for RelB, we speculate that RelB suppresses cigarette smoke-induced apoptosis by regulating the AhR. Using an in vitro model of cigarette smoke exposure (cigarette smoke extract [CSE]), we found that CSE down-regulated RelB expression in mouse lung fibroblasts, which was associated with elevated levels of cleaved PARP. Genetic ablation of RelB elevated CSE-induced apoptosis, including chromatin condensation, and reduced mitochondrial function. There was also more reactive oxygen species production in RelB-/- cells exposed to CSE. While there was no alteration in Nrf2 expression or localization between RelB-/- and wild type cells in response to CSE, RelB-/- cells displayed significantly decreased AhR mRNA and protein expression, concomitant with loss of AhR target gene expression (Cyp1a1, Cyp1b1, Nqo1). Finally, we found that RelB binds to the Ahr gene at 3 sites to potentially increase its expression via transcriptional induction. These data support that RelB suppresses cigarette smoke-induced apoptosis, potentially by increasing the AhR. Together, these two proteins may comprise an important cell survival signaling pathway that reduces apoptosis upon cigarette smoke exposure.
Collapse
|
24
|
Briseño CG, Gargaro M, Durai V, Davidson JT, Theisen DJ, Anderson DA, Novack DV, Murphy TL, Murphy KM. Deficiency of transcription factor RelB perturbs myeloid and DC development by hematopoietic-extrinsic mechanisms. Proc Natl Acad Sci U S A 2017; 114:3957-3962. [PMID: 28348230 PMCID: PMC5393217 DOI: 10.1073/pnas.1619863114] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
RelB is an NF-κB family transcription factor activated in the noncanonical pathway downstream of NF-κB-inducing kinase (NIK) and TNF receptor family members including lymphotoxin-β receptor (LTβR) and CD40. Early analysis suggested that RelB is required for classical dendritic cell (cDC) development based on a severe reduction of cDCs in Relb-/- mice associated with profound myeloid expansion and perturbations in B and T cells. Subsequent analysis of radiation chimeras generated from wild-type and Relb-/- bone marrow showed that RelB exerts cell-extrinsic actions on some lineages, but it has remained unclear whether the impact of RelB on cDC development is cell-intrinsic or -extrinsic. Here, we reevaluated the role of RelB in cDC and myeloid development using a series of radiation chimeras. We found that there was no cell-intrinsic requirement for RelB for development of most cDC subsets, except for the Notch2- and LTβR-dependent subset of splenic CD4+ cDC2s. These results identify a relatively restricted role of RelB in DC development. Moreover, the myeloid expansion in Relb-/- mice resulted from hematopoietic-extrinsic actions of RelB. This result suggests that there is an unrecognized but critical role for RelB within the nonhematopoietic niche that controls normal myelopoiesis.
Collapse
|
25
|
Salazar F, Awuah D, Negm OH, Shakib F, Ghaemmaghami AM. The role of indoleamine 2,3-dioxygenase-aryl hydrocarbon receptor pathway in the TLR4-induced tolerogenic phenotype in human DCs. Sci Rep 2017; 7:43337. [PMID: 28256612 PMCID: PMC5335671 DOI: 10.1038/srep43337] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Accepted: 01/25/2017] [Indexed: 12/27/2022] Open
Abstract
A controlled inflammatory response is required for protection against infection, but persistent inflammation causes tissue damage. Dendritic cells (DCs) have a unique capacity to promote both inflammatory and anti-inflammatory processes. One key mechanism involved in DC-mediated immunosuppression is the expression of tryptophan-metabolizing enzyme indoleamine 2,3-dioxygenase (IDO). IDO has been implicated in diverse processes in health and disease but its role in endotoxin tolerance in human DCs is still controversial. Here we investigated the role of IDO in shaping DCs phenotype and function under endotoxin tolerance conditions. Our data show that TLR4 ligation in LPS-primed DCs, induced higher levels of both IDO isoforms together with the transcription factor aryl-hydrocarbon receptor (AhR), compared to unprimed controls. Additionally, LPS conditioning induced an anti-inflammatory phenotype in DCs - with an increase in IL-10 and higher expression of programmed death ligand (PD-L)1 and PD-L2 - which were partially dependent on IDO. Furthermore, we demonstrated that the AhR-IDO pathway was responsible for the preferential activation of non-canonical NF-κB pathway in LPS-conditioned DCs. These data provide new insight into the mechanisms of the TLR4-induced tolerogenic phenotype in human DCs, which can help the better understanding of processes involved in induction and resolution of chronic inflammation and tolerance.
Collapse
MESH Headings
- B7-H1 Antigen/genetics
- B7-H1 Antigen/immunology
- Basic Helix-Loop-Helix Transcription Factors/genetics
- Basic Helix-Loop-Helix Transcription Factors/immunology
- Cell Adhesion Molecules/genetics
- Cell Adhesion Molecules/immunology
- Cell Differentiation/drug effects
- Dendritic Cells/cytology
- Dendritic Cells/drug effects
- Dendritic Cells/immunology
- Gene Expression Regulation
- Granulocyte-Macrophage Colony-Stimulating Factor/pharmacology
- Humans
- Immune Tolerance
- Indoleamine-Pyrrole 2,3,-Dioxygenase/genetics
- Indoleamine-Pyrrole 2,3,-Dioxygenase/immunology
- Interleukin-10/genetics
- Interleukin-10/immunology
- Interleukin-4/pharmacology
- Lectins, C-Type/genetics
- Lectins, C-Type/immunology
- Lipopolysaccharides/pharmacology
- Monocytes/cytology
- Monocytes/drug effects
- Monocytes/immunology
- NF-kappa B/genetics
- NF-kappa B/immunology
- Primary Cell Culture
- Programmed Cell Death 1 Ligand 2 Protein/genetics
- Programmed Cell Death 1 Ligand 2 Protein/immunology
- Protein Serine-Threonine Kinases/genetics
- Protein Serine-Threonine Kinases/immunology
- Receptors, Aryl Hydrocarbon/genetics
- Receptors, Aryl Hydrocarbon/immunology
- Receptors, Cell Surface/genetics
- Receptors, Cell Surface/immunology
- Signal Transduction
- TNF Receptor-Associated Factor 3/genetics
- TNF Receptor-Associated Factor 3/immunology
- Toll-Like Receptor 4/genetics
- Toll-Like Receptor 4/immunology
- Transcription Factor RelB/genetics
- Transcription Factor RelB/immunology
- NF-kappaB-Inducing Kinase
Collapse
|