RESUMO
Genetic alterations in signaling pathways that control cell-cycle progression, apoptosis, and cell growth are common hallmarks of cancer, but the extent, mechanisms, and co-occurrence of alterations in these pathways differ between individual tumors and tumor types. Using mutations, copy-number changes, mRNA expression, gene fusions and DNA methylation in 9,125 tumors profiled by The Cancer Genome Atlas (TCGA), we analyzed the mechanisms and patterns of somatic alterations in ten canonical pathways: cell cycle, Hippo, Myc, Notch, Nrf2, PI-3-Kinase/Akt, RTK-RAS, TGFß signaling, p53 and ß-catenin/Wnt. We charted the detailed landscape of pathway alterations in 33 cancer types, stratified into 64 subtypes, and identified patterns of co-occurrence and mutual exclusivity. Eighty-nine percent of tumors had at least one driver alteration in these pathways, and 57% percent of tumors had at least one alteration potentially targetable by currently available drugs. Thirty percent of tumors had multiple targetable alterations, indicating opportunities for combination therapy.
Assuntos
Bases de Dados Genéticas , Neoplasias/patologia , Transdução de Sinais/genética , Genes Neoplásicos , Humanos , Neoplasias/genética , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Proteínas Wnt/genética , Proteínas Wnt/metabolismoRESUMO
Spatiotemporal control of Wnt signaling is essential for the development and homeostasis of many tissues. The transmembrane E3 ubiquitin ligases ZNRF3 (zinc and ring finger 3) and RNF43 (ring finger protein 43) antagonize Wnt signaling by promoting degradation of frizzled receptors. ZNRF3 and RNF43 are frequently inactivated in human cancer, but the molecular and therapeutic implications remain unclear. Here, we demonstrate that adrenocortical-specific loss of ZNRF3, but not RNF43, results in adrenal hyperplasia that depends on Porcupine-mediated Wnt ligand secretion. Furthermore, we discovered a Wnt/ß-catenin signaling gradient in the adrenal cortex that is disrupted upon loss of ZNRF3. Unlike ß-catenin gain-of-function models, which induce high Wnt/ß-catenin activation and expansion of the peripheral cortex, ZNRF3 loss triggers activation of moderate-level Wnt/ß-catenin signaling that drives proliferative expansion of only the histologically and functionally distinct inner cortex. Genetically reducing ß-catenin dosage significantly reverses the ZNRF3-deficient phenotype. Thus, homeostatic maintenance of the adrenal cortex is dependent on varying levels of Wnt/ß-catenin activation, which is regulated by ZNRF3.
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Córtex Suprarrenal/metabolismo , Homeostase/genética , Ubiquitina-Proteína Ligases/metabolismo , Via de Sinalização Wnt/fisiologia , beta Catenina/metabolismo , Córtex Suprarrenal/citologia , Córtex Suprarrenal/crescimento & desenvolvimento , Doenças do Córtex Suprarrenal/fisiopatologia , Animais , Proliferação de Células/genética , Feminino , Técnicas de Inativação de Genes , Masculino , Camundongos , Modelos Animais , Ativação Transcricional/genética , Ubiquitina-Proteína Ligases/genéticaRESUMO
The nuclear receptor steroidogenic factor 1 (Sf1, Nr5a1, Ad4bp) is crucial for formation, development and function of steroidogenic tissues. A fetal adrenal enhancer (FAdE) in the Sf1 gene was previously identified to direct Sf1 expression exclusively in the fetal adrenal cortex and is bound by both Sf1 and Dax1. Here, we have examined the function of Sf1 SUMOylation and its interaction with Dax1 on FAdE function. A diffused prolonged pattern of FAdE expression and delayed regression of the postnatal fetal cortex (X-zone) were detected in both the SUMOylation-deficient-Sf12KR/2KR and Dax1 knockout mouse lines, with FAdE expression/activity retained in the postnatal 20αHSD-positive postnatal X-zone cells. In vitro studies indicated that Sf1 SUMOylation, although not directly influencing DNA binding, actually increased binding of Dax1 to Sf1 to further enhance transcriptional repression of FAdE. Taken together, these studies define a crucial repressor function of Sf1 SUMOylation and Dax1 in the physiological cessation of FAdE-mediated Sf1 expression and the resultant regression of the postnatal fetal cortex (X-zone).
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Córtex Suprarrenal/embriologia , Receptor Nuclear Órfão DAX-1/fisiologia , Regulação da Expressão Gênica no Desenvolvimento , Fator Esteroidogênico 1/fisiologia , Animais , Receptor Nuclear Órfão DAX-1/genética , Feminino , Células HEK293 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Processamento de Proteína Pós-Traducional , Reação em Cadeia da Polimerase em Tempo Real , Fator Esteroidogênico 1/genética , Sumoilação , Transcrição GênicaRESUMO
Lack of routine fresh or frozen tissue is a barrier to widespread transcriptomic analysis of adrenal cortical tumors and an impediment to translational research in endocrinology and endocrine oncology. Our group has previously pioneered the use of targeted amplicon-based next-generation sequencing for archival formalin-fixed paraffin-embedded (FFPE) adrenal tissue specimens to characterize the spectrum of somatic mutations in various forms of primary aldosteronism. Herein, we developed and validated a novel 194-amplicon targeted next-generation RNA sequencing (RNAseq) assay for transcriptomic analysis of adrenal tumors using clinical-grade FFPE specimens. Targeted RNAseq-derived expression values for 27 adrenal cortical tumors, including aldosterone-producing adenomas (APA; n=8), cortisol-producing adenomas (CPA; n=11), and adrenal cortical carcinomas (ACC; n=8), highlighted known differentially-expressed genes (DEGs; i. e., CYP11B2, IGF2, etc.) and tumor type-specific transcriptional modules (i. e., high cell cycle/proliferation transcript expression in ACC, etc.), and a subset of DEGs was validated orthogonally using quantitative reverse transcription PCR (qRT-PCR). Finally, unsupervised hierarchical clustering using a subset of high-confidence DEGs revealed three discrete clusters representing APA, CPA, and ACC tumors with corresponding unique gene expression signatures, suggesting potential clinical utility for a transcriptomic-based approach to tumor classification. Overall, these data support the use of targeted amplicon-based RNAseq for comprehensive transcriptomic profiling of archival FFPE adrenal tumor material and indicate that this approach may facilitate important translational research opportunities for the study of these tumors.
Assuntos
Neoplasias do Córtex Suprarrenal/classificação , Neoplasias do Córtex Suprarrenal/diagnóstico , Biomarcadores Tumorais/genética , Inclusão em Parafina/métodos , RNA-Seq/métodos , Transcriptoma , Neoplasias do Córtex Suprarrenal/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Diagnóstico Diferencial , Feminino , Seguimentos , Formaldeído/química , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , PrognósticoRESUMO
Since its discovery nearly 30 years ago, the Hedgehog (Hh) signaling pathway has been shown to be pivotal in many developmental and pathophysiological processes in several steroidogenic tissues, including the testis, ovary, adrenal cortex, and placenta. New evidence links the evolutionarily conserved Hh pathway to the steroidogenic organs, demonstrating how Hh signaling can influence their development and homeostasis and can act in concert with steroids to mediate physiological functions. In this review, we highlight the role of the components of the Hh signaling pathway in steroidogenesis of endocrine tissues.
Assuntos
Proteínas Hedgehog/fisiologia , Transdução de Sinais/fisiologia , Esteroides/metabolismo , Glândulas Suprarrenais/metabolismo , Animais , Feminino , Humanos , Masculino , Ovário/metabolismo , Placenta/metabolismo , Gravidez , Testículo/metabolismoRESUMO
The lineage relationships of fetal adrenal cells and adrenal capsular cells to the differentiated adrenal cortex are not fully understood. Existing data support a role for each cell type as a progenitor for cells of the adult cortex. This report reveals that subsets of capsular cells are descendants of fetal adrenocortical cells that once expressed Nr5a1. These fetal adrenocortical cell descendants within the adrenal capsule express Gli1, a known marker of progenitors of steroidogenic adrenal cells. The capsule is also populated by cells that express Tcf21, a known inhibitor of Nr5a1 gene expression. We demonstrate that Tcf21-expressing cells give rise to Nr5a1-expressing cells but only before capsular formation. After the capsule has formed, capsular Tcf21-expressing cells give rise only to non-steroidogenic stromal adrenocortical cells, which also express collagen 1a1, desmin and platelet-derived growth factor (alpha polypeptide) but not Nr5a1. These observations integrate prior observations that define two separate origins of adult adrenocortical steroidogenic cells (fetal adrenal cortex and/or the adrenal capsule). Thus, these observations predict a unique temporal and/or spatial role of adult cortical cells that arise directly from either fetal cortical cells or from fetal cortex-derived capsular cells. Last, the data uncover the mechanism by which two populations of fetal cells (fetal cortex derived Gli1-expressing cells and mesenchymal Tcf21-expressing mesenchymal cells) participate in the establishment of the homeostatic capsular progenitor cell niche of the adult cortex.
Assuntos
Córtex Suprarrenal/citologia , Córtex Suprarrenal/embriologia , Linhagem da Célula , Feto/citologia , Células-Tronco/citologia , Esteroides/metabolismo , Envelhecimento/metabolismo , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Homeostase , Camundongos , Modelos Biológicos , Fator Esteroidogênico 1/metabolismo , Células Estromais , Fatores de Transcrição/metabolismo , Proteína GLI1 em Dedos de ZincoRESUMO
Long interspersed element-1 (LINE-1 or L1) retrotransposition continues to affect human genome evolution. L1s can retrotranspose in the germline, during early development and in select somatic cells; however, the host response to L1 retrotransposition remains largely unexplored. Here we show that reporter genes introduced into the genome of various human embryonic carcinoma-derived cell lines (ECs) by L1 retrotransposition are rapidly and efficiently silenced either during or immediately after their integration. Treating ECs with histone deacetylase inhibitors rapidly reverses this silencing, and chromatin immunoprecipitation experiments revealed that reactivation of the reporter gene was correlated with changes in chromatin status at the L1 integration site. Under our assay conditions, rapid silencing was also observed when reporter genes were delivered into ECs by mouse L1s and a zebrafish LINE-2 element, but not when similar reporter genes were delivered into ECs by Moloney murine leukaemia virus or human immunodeficiency virus, suggesting that these integration events are silenced by distinct mechanisms. Finally, we demonstrate that subjecting ECs to culture conditions that promote differentiation attenuates the silencing of reporter genes delivered by L1 retrotransposition, but that differentiation, in itself, is not sufficient to reactivate previously silenced reporter genes. Thus, our data indicate that ECs differ from many differentiated cells in their ability to silence reporter genes delivered by L1 retrotransposition.
Assuntos
Células-Tronco de Carcinoma Embrionário/metabolismo , Epigênese Genética/genética , Inativação Gênica , Retroelementos/genética , Animais , Diferenciação Celular/genética , Diferenciação Celular/fisiologia , Linhagem Celular Tumoral , Cromatina/efeitos dos fármacos , Cromatina/genética , Cromatina/metabolismo , Imunoprecipitação da Cromatina , Células-Tronco de Carcinoma Embrionário/patologia , Epigênese Genética/efeitos dos fármacos , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Inativação Gênica/efeitos dos fármacos , Genes Reporter/genética , Engenharia Genética , Vetores Genéticos/genética , Genoma Humano/genética , HIV/genética , Inibidores de Histona Desacetilases/farmacologia , Humanos , Elementos Nucleotídeos Longos e Dispersos/genética , Masculino , Camundongos , Modelos Genéticos , Vírus da Leucemia Murina de Moloney/genética , Peixe-Zebra/genéticaRESUMO
BACKGROUND: Adrenocortical carcinoma is a rare, aggressive cancer for which few treatment options are available. Linsitinib (OSI-906) is a potent, oral small molecule inhibitor of both IGF-1R and the insulin receptor, which has shown acceptable tolerability and preliminary evidence of anti-tumour activity. We assessed linsitinib against placebo to investigate efficacy in patients with advanced adrenocortical carcinoma. METHODS: In this international, double-blind, placebo-controlled phase 3 study, adult patients with histologically confirmed locally advanced or metastatic adrenocortical carcinoma were recruited at clinical sites in nine countries. Patients were randomly assigned (2:1) twice-daily 150 mg oral linsitinib or placebo via a web-based, centralised randomisation system and stratified according to previous systemic cytotoxic chemotherapy for adrenocortical carcinoma, Eastern Cooperative Oncology Group performance status, and use of one or more oral antihyperglycaemic therapy at randomisation. Allocation was concealed by blinded block size and permuted block randomisation. The primary endpoint was overall survival, calculated from date of randomisation until death from any cause. The primary analysis was done in the intention-to-treat population. This study is registered with ClinicalTrials.gov, number NCT00924989. FINDINGS: Between Dec 2, 2009, and July 11, 2011, 139 patients were enrolled, of whom 90 were assigned to linsitinib and 49 to placebo. The trial was unblinded on March 19, 2012, based on data monitoring committee recommendation due to the failure of linsitinib to increase either progression-free survival or overall survival. At database lock and based on 92 deaths, no difference in overall survival was noted between linsitinib and placebo (median 323 days [95% CI 256-507] vs 356 days [249-556]; hazard ratio 0·94 [95% CI 0·61-1·44]; p=0·77). The most common treatment-related adverse events of grade 3 or worse in the linsitinib group were fatigue (three [3%] patients vs no patients in the placebo group), nausea (two [2%] vs none), and hyperglycaemia (two [2%] vs none). No adverse events in the linsitinib group were deemed to be treatment related; one death (due to sepsis and megacolon) in the placebo group was deemed to be treatment related. INTERPRETATION: Linsitinib did not increase overall survival and so cannot be recommended as treatment for this general patient population. Further studies of IGF-1R and insulin receptor inhibitors, together with genetic profiling of responders, might pave the way toward individualised and improved therapeutic options in adrenocortical carcinoma. FUNDING: Astellas.
Assuntos
Carcinoma Adrenocortical/tratamento farmacológico , Imidazóis/administração & dosagem , Metástase Neoplásica/tratamento farmacológico , Pirazinas/administração & dosagem , Carcinoma Adrenocortical/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Intervalo Livre de Doença , Método Duplo-Cego , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Feminino , Humanos , Imidazóis/efeitos adversos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica/patologia , Placebos , Inibidores de Proteínas Quinases/administração & dosagem , Pirazinas/efeitos adversosRESUMO
BACKGROUND: Adrenocortical carcinoma (ACC) is a rare and aggressive malignancy with poor prognosis, as a majority of patients present with advanced disease. Current adjuvant strategies for metastatic patients include mitotane or other cytotoxic agents and carry a significant morbidity as well as a low (<10 %) 5-year survival. Withanolides, including withaferin A, are novel chemotherapeutic agents with potent targeted effects in medullary thyroid cancer and a number of solid malignancies with low toxicity in vivo. We hypothesize that novel naturally derived withanolides will have potent targeted anti-cancer activity against ACCs. METHODS: In vitro cell viability of ACC cell lines (Y1 and SW13) was measured using MTS cell proliferation assay. Cell cycle and apoptotic analysis studied using annexin V/propidium iodide staining on flow cytometry (FC) and targeted molecular mechanisms of withanolide cytotoxicity were assessed using standard Western blot analysis. RESULTS: All the withanolides potently reduced ACC cell viability on MTS assay with 7- to 185-fold higher selectivity than normal fibroblasts. Cell cycle analysis demonstrated a shift in cell cycle arrest from G1/G0 to G2/M with induction of apoptosis at nanomolar concentrations of withanolides. Unlike current ACC therapeutics, withanolides modulated expression of several key oncogenic pathway proteins in ACCs by Western blot, including Jagged 1, MAPK, and Akt/mTOR pathway proteins in a dose-dependent manner after 24 h drug treatment of SW13 cells. CONCLUSION: These results demonstrate the first evidence of the anticancer efficacy of withanolides in ACC cells and provide support for future translational evaluation of these compounds as novel therapeutic agents for ACC patients.
Assuntos
Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Sistemas de Liberação de Medicamentos/métodos , Vitanolídeos/farmacologia , Neoplasias das Glândulas Suprarrenais/tratamento farmacológico , Neoplasias das Glândulas Suprarrenais/cirurgia , Carcinoma Adrenocortical/tratamento farmacológico , Carcinoma Adrenocortical/cirurgia , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Humanos , Sensibilidade e Especificidade , Células Tumorais Cultivadas/efeitos dos fármacosRESUMO
Hyperaldosteronism is often associated with inappropriate aldosterone production and aldosterone synthase (Cyp11b2) expression. Normally, Cyp11b2 expression is limited to the adrenal zona glomerulosa (ZG) and regulated by angiotensin II which signals through Gq protein-coupled receptors. As cells migrate inwards, they differentiate into 11ß-hydroxylase-expressing zona fasciculata (ZF) cells lacking Cyp11b2. The mechanism causing ZG-specific aldosterone biosynthesis is still unclear. We investigated the effect of chronic Gq signaling using transgenic mice with a clozapine N-oxide (CNO)-activated human M3 muscarinic receptor (DREADD) coupled to Gq (hM3Dq) that was expressed throughout the adrenal cortex. CNO raised circulating aldosterone in the presence of a high sodium diet with greater response seen in females compared to males. Immunohistochemistry and transcriptomics indicated disrupted zonal Cyp11b2 expression while Wnt signaling remained unchanged. Chronic Gq-DREADD signaling also induced an intra-adrenal RAAS in CNO-treated mice. Chronic Gq signaling disrupted adrenal cortex zonal aldosterone production associated with ZF expression of Cyp11b2.
Assuntos
Córtex Suprarrenal , Hiperaldosteronismo , Masculino , Feminino , Humanos , Camundongos , Animais , Zona Fasciculada , Aldosterona/metabolismo , Córtex Suprarrenal/metabolismo , Zona Glomerulosa/metabolismo , Citocromo P-450 CYP11B2/genética , Via de Sinalização Wnt , Camundongos TransgênicosRESUMO
The steroid hormone aldosterone, produced by the zona glomerulosa (zG) of the adrenal gland, is a master regulator of plasma electrolytes and blood pressure. While aldosterone control by the renin-angiotensin system is well understood, other key regulatory factors have remained elusive. Here, we replicated a prior association between a non-coding variant in WNT2B and an increased risk of primary aldosteronism, a prevalent and debilitating disease caused by excessive aldosterone production. We further show that in both mice and humans, WNT2B is expressed in the mesenchymal capsule surrounding the adrenal cortex, in close proximity to the zG. Global loss of Wnt2b in the mouse results in a dysmorphic and hypocellular zG, with impaired aldosterone production. Similarly, humans harboring WNT2B loss-of-function mutations develop a novel form of Familial Hyperreninemic Hypoaldosteronism, designated here as Type 4. Additionally, we demonstrate that WNT2B signals by activating the non-canonical Wnt/planar cell polarity pathway. Our findings identify WNT2B as a key regulator of zG function and aldosterone production with important clinical implications. Highlights: WNT2B variant is associated with increased risk for primary aldosteronism Wnt2b knock-out mice show defects in adrenal morphology Wnt2b knock-out mice have hyperreninemic hypoaldosteronism WNT2B activates non-canonical Wnt/planar cell polarity signalingWNT2B deficiency causes a new form of familial hyperreninemic hypoaldosteronism.
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EndoBridge 2023 took place on October 20-22, 2023, in Antalya, Turkey. Accredited by the European Council, the 3-day scientific program of the 11th Annual Meeting of EndoBridge included state-of-the-art lectures and interactive small group discussion sessions incorporating interesting and challenging clinical cases led by globally recognized leaders in the field and was well attended by a highly diverse audience. Following its established format over the years, the program provided a comprehensive update across all aspects of endocrinology and metabolism, including topics in pituitary, thyroid, bone, and adrenal disorders, neuroendocrine tumors, diabetes mellitus, obesity, nutrition, and lipid disorders. As usual, the meeting was held in English with simultaneous translation into Russian, Arabic, and Turkish. The abstracts of clinical cases presented by the delegates during oral and poster sessions have been published in JCEM Case Reports. Herein, we provide a paper on highlights and pearls of the meeting sessions covering a wide range of subjects, from thyroid nodule stratification to secondary osteoporosis and from glycemic challenges in post-bariatric surgery to male hypogonadism. This report emphasizes the latest developments in the field, along with clinical approaches to common endocrine issues. The 12th annual meeting of EndoBridge will be held on October 17-20, 2024 in Antalya, Turkey.
Assuntos
Doenças do Sistema Endócrino , Humanos , Doenças do Sistema Endócrino/terapia , Endocrinologia/história , Osteoporose/terapiaRESUMO
Dysregulation of the WNT and insulin-like growth factor 2 (IGF2) signaling pathways has been implicated in sporadic and syndromic forms of adrenocortical carcinoma (ACC). Abnormal ß-catenin staining and CTNNB1 mutations are reported to be common in both adrenocortical adenoma and ACC, whereas elevated IGF2 expression is associated primarily with ACC. To better understand the contribution of these pathways in the tumorigenesis of ACC, we examined clinicopathological and molecular data and used mouse models. Evaluation of adrenal tumors from 118 adult patients demonstrated an increase in CTNNB1 mutations and abnormal ß-catenin accumulation in both adrenocortical adenoma and ACC. In ACC, these features were adversely associated with survival. Mice with stabilized ß-catenin exhibited a temporal progression of increased adrenocortical hyperplasia, with subsequent microscopic and macroscopic adenoma formation. Elevated Igf2 expression alone did not cause hyperplasia. With the combination of stabilized ß-catenin and elevated Igf2 expression, adrenal glands were larger, displayed earlier onset of hyperplasia, and developed more frequent macroscopic adenomas (as well as one carcinoma). Our results are consistent with a model in which dysregulation of one pathway may result in adrenal hyperplasia, but accumulation of a second or multiple alterations is necessary for tumorigenesis.
Assuntos
Neoplasias do Córtex Suprarrenal/patologia , Transformação Celular Neoplásica/patologia , Progressão da Doença , Fator de Crescimento Insulin-Like II/metabolismo , beta Catenina/metabolismo , Proteína da Polipose Adenomatosa do Colo/metabolismo , Corticosteroides/metabolismo , Neoplasias do Córtex Suprarrenal/genética , Animais , Biomarcadores Tumorais/metabolismo , Transformação Celular Neoplásica/genética , Metilação de DNA/genética , Regulação Neoplásica da Expressão Gênica , Impressão Genômica , Humanos , Hiperplasia , Fator 1 de Ligação ao Facilitador Linfoide/metabolismo , Camundongos , Camundongos Knockout , Análise Multivariada , Mutação/genética , Gradação de Tumores , Estadiamento de Neoplasias , Prognóstico , Modelos de Riscos Proporcionais , Estabilidade Proteica , Transporte Proteico , Regulação para Cima/genéticaRESUMO
Introduction: Graves' disease (GD) is an autoimmune disorder caused by autoantibodies against the thyroid stimulating hormone receptor (TSHR) leading to overstimulation of the thyroid gland. Thyroid eye disease (TED) is the most common extra thyroidal manifestation of GD. Therapeutic options to treat TED are very limited and novel treatments need to be developed. In the present study we investigated the effect of linsitinib, a dual small-molecule kinase inhibitor of the insulin-like growth factor 1 receptor (IGF-1R) and the Insulin receptor (IR) on the disease outcome of GD and TED. Methods: Linsitinib was administered orally for four weeks with therapy initiating in either the early ("active") or the late ("chronic") phases of the disease. In the thyroid and the orbit, autoimmune hyperthyroidism and orbitopathy were analyzed serologically (total anti-TSHR binding antibodies, stimulating anti TSHR antibodies, total T4 levels), immunohistochemically (H&E-, CD3-, TNFa- and Sirius red staining) and with immunofluorescence (F4/80 staining). An MRI was performed to quantify in vivo tissue remodeling inside the orbit. Results: Linsitinib prevented autoimmune hyperthyroidism in the early state of the disease, by reducing morphological changes indicative for hyperthyroidism and blocking T-cell infiltration, visualized by CD3 staining. In the late state of the disease linsitinib had its main effect in the orbit. Linsitinib reduced immune infiltration of T-cells (CD3 staining) and macrophages (F4/80 and TNFa staining) in the orbita in experimental GD suggesting an additional, direct effect of linsitinib on the autoimmune response. In addition, treatment with linsitinib normalized the amount of brown adipose tissue in both the early and late group. An in vivo MRI of the late group was performed and revealed a marked decrease of inflammation, visualized by 19F MR imaging, significant reduction of existing muscle edema and formation of brown adipose tissue. Conclusion: Here, we demonstrate that linsitinib effectively prevents development and progression of thyroid eye disease in an experimental murine model for Graves' disease. Linsitinib improved the total disease outcome, indicating the clinical significance of the findings and providing a path to therapeutic intervention of Graves' Disease. Our data support the use of linsitinib as a novel treatment for thyroid eye disease.
Assuntos
Doença de Graves , Oftalmopatia de Graves , Inibidores de Proteínas Quinases , Receptor IGF Tipo 1 , Animais , Camundongos , Doença de Graves/tratamento farmacológico , Oftalmopatia de Graves/tratamento farmacológico , Hipertireoidismo , Imidazóis , Inibidores de Proteínas Quinases/uso terapêutico , Receptor IGF Tipo 1/antagonistas & inibidoresRESUMO
Introduction: Graves' disease is an autoimmune disorder caused by auto-antibodies against the thyroid stimulating hormone receptor (TSHR). Overstimulation of the TSHR induces hyperthyroidism and thyroid eye disease (TED) as the most common extra thyroidal manifestation of Graves' disease. In TED, the TSHR cross talks with the insulin-like growth factor 1 receptor (IGF-1R) in orbital fibroblasts leading to inflammation, deposition of hyaluronan and adipogenesis. The bone marrow may play an important role in autoimmune diseases, but its role in Graves' disease and TED is unknown. Here, we investigated whether induction of experimental Graves' disease and accompanying TED involves bone marrow activation and whether interference with IGF-1R signaling prevents this activation. Results: Immunization of mice with TSHR resulted in an increase the numbers of CD4-positive T-lymphocytes (p ≤0.0001), which was normalized by linsitinib (p = 0.0029), an increase of CD19-positive B-lymphocytes (p= 0.0018), which was unaffected by linsitinib and a decrease of GR1-positive cells (p= 0.0038), which was prevented by linsitinib (p= 0.0027). In addition, we observed an increase of Sca-1 positive hematopietic stem cells (p= 0.0007) and of stromal cell-derived factor 1 (SDF-1) (p ≤0.0001) after immunization with TSHR which was prevented by linsitinib (Sca-1: p= 0.0008, SDF-1: p ≤0.0001). TSHR-immunization also resulted in upregulation of CCL-5, IL-6 and osteopontin (all p ≤0.0001) and a concomitant decrease of the immune-inhibitory cytokines IL-10 (p= 0.0064) and PGE2 (p ≤0.0001) in the bone marrow (all p≤ 0.0001). Treatment with the IGF-1R antagonist linsitinib blocked these events (all p ≤0.0001). We further demonstrate a down-regulation of arginase-1 expression (p= 0.0005) in the bone marrow in TSHR immunized mice, with a concomitant increase of local arginine (p ≤0.0001). Linsitinib induces an upregulation of arginase-1 resulting in low arginase levels in the bone marrow. Reconstitution of arginine in bone marrow cells in vitro prevented immune-inhibition by linsitinib. Conclusion: Collectively, these data indicate that the bone marrow is activated in experimental Graves' disease and TED, which is prevented by linsitinib. Linsitinib-mediated immune-inhibition is mediated, at least in part, by arginase-1 up-regulation, consumption of arginine and thereby immune inhibition.
Assuntos
Doenças Autoimunes , Doença de Graves , Oftalmopatia de Graves , Camundongos , Animais , Oftalmopatia de Graves/metabolismo , Arginase , Medula Óssea/metabolismo , Receptores da Tireotropina , Doenças Autoimunes/complicações , ArgininaRESUMO
Adrenocortical carcinoma (ACC) is a rare but highly aggressive cancer with limited treatment options and poor survival for patients with advanced disease. An improved understanding of the transcriptional programs engaged in ACC will help direct rational, targeted therapies. Whereas activating mutations in Wnt/ß-catenin signaling are frequently observed, the ß-catenin-dependent transcriptional targets that promote tumor progression are poorly understood. To address this question, we analyzed ACC transcriptome data and identified a novel Wnt/ß-catenin-associated signature in ACC enriched for the extracellular matrix (ECM) and predictive of poor survival. This suggested an oncogenic role for Wnt/ß-catenin in regulating the ACC microenvironment. We further investigated the minor fibrillar collagen, collagen XI alpha 1 (COL11A1), and found that COL11A1 expression originates specifically from cancer cells and is strongly correlated with both Wnt/ß-catenin activation and poor patient survival. Inhibition of constitutively active Wnt/ß-catenin signaling in the human ACC cell line, NCI-H295R, significantly reduced the expression of COL11A1 and other ECM components and decreased cancer cell viability. To investigate the preclinical potential of Wnt/ß-catenin inhibition in the adrenal microenvironment, we developed a minimally invasive orthotopic xenograft model of ACC and demonstrated that treatment with the newly developed Wnt/ß-catenin:TBL1 inhibitor Tegavivint significantly reduced tumor growth. Together, our data support that the inhibition of aberrantly active Wnt/ß-catenin disrupts transcriptional reprogramming of the microenvironment and reduces ACC growth and survival. Furthermore, this ß-catenin-dependent oncogenic program can be therapeutically targeted with a newly developed Wnt/ß-catenin inhibitor. These results show promise for the further clinical development of Wnt/ß-catenin inhibitors in ACC and unveil a novel Wnt/ß-catenin-regulated transcriptome.
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The pituitary gland regulates growth, metabolism, reproduction, the stress response, uterine contractions, lactation, and water retention. It secretes hormones in response to hypothalamic input, end organ feedback, and diurnal cues. The mechanisms by which pituitary stem cells are recruited to proliferate, maintain quiescence, or differentiate into specific cell types, especially thyrotropes, are not well understood. We used single-cell RNA sequencing in juvenile P7 mouse pituitary cells to identify novel factors in pituitary cell populations, with a focus on thyrotropes and rare subtypes. We first observed cells coexpressing markers of both thyrotropes and gonadotropes, such as Pou1f1 and Nr5a1. This was validated in vivo by both immunohistochemistry and lineage tracing of thyrotropes derived from Nr5a1-Cre; mTmG mice and demonstrates that Nr5a1-progenitors give rise to a proportion of thyrotropes during development. Our data set also identifies novel factors expressed in pars distalis and pars tuberalis thyrotropes, including the Shox2b isoform in all thyrotropes and Sox14 specifically in Pou1f1-negative pars tuberalis thyrotropes. We have therefore used single-cell transcriptomics to determine a novel developmental trajectory for thyrotropes and potential novel regulators of thyrotrope populations.
Assuntos
Doenças da Hipófise , Adeno-Hipófise , Gravidez , Feminino , Camundongos , Animais , Tireotropina/metabolismo , Hipófise/metabolismo , Fatores de Transcrição/metabolismo , Doenças da Hipófise/metabolismo , Imuno-Histoquímica , Adeno-Hipófise/metabolismo , Fatores de Transcrição SOXB2/metabolismoRESUMO
Aging markedly increases cancer risk, yet our mechanistic understanding of how aging influences cancer initiation is limited. Here we demonstrate that the loss of ZNRF3, an inhibitor of Wnt signaling that is frequently mutated in adrenocortical carcinoma, leads to the induction of cellular senescence that remodels the tissue microenvironment and ultimately permits metastatic adrenal cancer in old animals. The effects are sexually dimorphic, with males exhibiting earlier senescence activation and a greater innate immune response, driven in part by androgens, resulting in high myeloid cell accumulation and lower incidence of malignancy. Conversely, females present a dampened immune response and increased susceptibility to metastatic cancer. Senescence-recruited myeloid cells become depleted as tumors progress, which is recapitulated in patients in whom a low myeloid signature is associated with worse outcomes. Our study uncovers a role for myeloid cells in restraining adrenal cancer with substantial prognostic value and provides a model for interrogating pleiotropic effects of cellular senescence in cancer.
Assuntos
Neoplasias do Córtex Suprarrenal , Carcinoma Adrenocortical , Masculino , Animais , Feminino , Carcinoma Adrenocortical/genética , Envelhecimento , Senescência Celular , Transdução de Sinais , Neoplasias do Córtex Suprarrenal/genética , Microambiente TumoralRESUMO
Adrenocortical carcinoma (ACC) is a rare cancer in which tissue-specific differentiation is paradoxically associated with dismal outcomes. The differentiated ACC subtype CIMP-high is prevalent, incurable, and routinely fatal. CIMP-high ACC possess abnormal DNA methylation and frequent ß-catenin-activating mutations. Here, we demonstrated that ACC differentiation is maintained by a balance between nuclear, tissue-specific ß-catenin-containing complexes, and the epigenome. On chromatin, ß-catenin bound master adrenal transcription factor SF1 and hijacked the adrenocortical super-enhancer landscape to maintain differentiation in CIMP-high ACC; off chromatin, ß-catenin bound histone methyltransferase EZH2. SF1/ß-catenin and EZH2/ß-catenin complexes present in normal adrenals persisted through all phases of ACC evolution. Pharmacologic EZH2 inhibition in CIMP-high ACC expelled SF1/ß-catenin from chromatin and favored EZH2/ß-catenin assembly, erasing differentiation and restraining cancer growth in vitro and in vivo. These studies illustrate how tissue-specific programs shape oncogene selection, surreptitiously encoding targetable therapeutic vulnerabilities. SIGNIFICANCE: Oncogenic ß-catenin can use tissue-specific partners to regulate cellular differentiation programs that can be reversed by epigenetic therapies, identifying epigenetic control of differentiation as a viable target for ß-catenin-driven cancers.
Assuntos
Neoplasias do Córtex Suprarrenal , Carcinoma Adrenocortical , Humanos , beta Catenina/genética , beta Catenina/metabolismo , Carcinoma Adrenocortical/genética , Carcinoma Adrenocortical/metabolismo , Carcinoma Adrenocortical/patologia , Neoplasias do Córtex Suprarrenal/genética , Neoplasias do Córtex Suprarrenal/patologia , Epigênese Genética , Cromatina/genéticaRESUMO
The shelterin complex at mammalian telomeres contains the single-stranded DNA-binding protein Pot1, which regulates telomere length and protects chromosome ends. Pot1 binds Tpp1, the shelterin component that connects Pot1 to the duplex telomeric DNA-binding proteins Trf1 and Trf2. Control of telomere length requires that Pot1 binds Tpp1 as well as the single-stranded telomeric DNA, but it is not known whether the protective function of Pot1 depends on Tpp1. Alternatively, Pot1 might function similarly to the Pot1-like proteins of budding and fission yeast, which have no known Tpp1-like connection to the duplex telomeric DNA. Using mutant mouse cells with diminished Tpp1 levels, RNA interference directed to mouse Tpp1 and Pot1, and complementation of mouse Pot1 knockout cells with human and mouse Pot1 variants, we show here that Tpp1 is required for the protective function of mammalian Pot1 proteins.