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1.
Cell ; 173(2): 470-484.e18, 2018 04 05.
Artículo en Inglés | MEDLINE | ID: mdl-29551267

RESUMEN

B cell activation during normal immune responses and oncogenic transformation impose increased metabolic demands on B cells and their ability to retain redox homeostasis. While the serine/threonine-protein phosphatase 2A (PP2A) was identified as a tumor suppressor in multiple types of cancer, our genetic studies revealed an essential role of PP2A in B cell tumors. Thereby, PP2A redirects glucose carbon utilization from glycolysis to the pentose phosphate pathway (PPP) to salvage oxidative stress. This unique vulnerability reflects constitutively low PPP activity in B cells and transcriptional repression of G6PD and other key PPP enzymes by the B cell transcription factors PAX5 and IKZF1. Reflecting B-cell-specific transcriptional PPP-repression, glucose carbon utilization in B cells is heavily skewed in favor of glycolysis resulting in lack of PPP-dependent antioxidant protection. These findings reveal a gatekeeper function of the PPP in a broad range of B cell malignancies that can be efficiently targeted by small molecule inhibition of PP2A and G6PD.


Asunto(s)
Carbono/metabolismo , Glucosa/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/patología , Animales , Linfocitos B/citología , Linfocitos B/metabolismo , Línea Celular Tumoral , Supervivencia Celular , Glucosafosfato Deshidrogenasa/genética , Glucosafosfato Deshidrogenasa/metabolismo , Glucólisis , Humanos , Factor de Transcripción Ikaros/genética , Factor de Transcripción Ikaros/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos NOD , Estrés Oxidativo , Factor de Transcripción PAX5/genética , Factor de Transcripción PAX5/metabolismo , Vía de Pentosa Fosfato , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Proteína Fosfatasa 2/deficiencia , Proteína Fosfatasa 2/genética , Proteína Fosfatasa 2/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Transcripción Genética
2.
Mol Cell ; 81(10): 2094-2111.e9, 2021 05 20.
Artículo en Inglés | MEDLINE | ID: mdl-33878293

RESUMEN

Even though SYK and ZAP70 kinases share high sequence homology and serve analogous functions, their expression in B and T cells is strictly segregated throughout evolution. Here, we identified aberrant ZAP70 expression as a common feature in a broad range of B cell malignancies. We validated SYK as the kinase that sets the thresholds for negative selection of autoreactive and premalignant clones. When aberrantly expressed in B cells, ZAP70 competes with SYK at the BCR signalosome and redirects SYK from negative selection to tonic PI3K signaling, thereby promoting B cell survival. In genetic mouse models for B-ALL and B-CLL, conditional expression of Zap70 accelerated disease onset, while genetic deletion impaired malignant transformation. Inducible activation of Zap70 during B cell development compromised negative selection of autoreactive B cells, resulting in pervasive autoantibody production. Strict segregation of the two kinases is critical for normal B cell selection and represents a central safeguard against the development of autoimmune disease and B cell malignancies.


Asunto(s)
Autoinmunidad , Neoplasias/enzimología , Neoplasias/prevención & control , Quinasa Syk/metabolismo , Proteína Tirosina Quinasa ZAP-70/metabolismo , Animales , Antígenos CD19/metabolismo , Linfocitos B , Calcio/metabolismo , Diferenciación Celular , Transformación Celular Neoplásica , Activación Enzimática , Humanos , Tolerancia Inmunológica , Linfoma de Células B/enzimología , Linfoma de Células B/patología , Ratones , Modelos Genéticos , Factores de Transcripción NFATC/metabolismo , Proteínas de Neoplasias , Fosfatidilinositol 3-Quinasas/metabolismo , Unión Proteica , Receptores de Antígenos de Linfocitos B/metabolismo , Transducción de Señal
3.
Nature ; 583(7818): 845-851, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32699415

RESUMEN

Malignant transformation of cells typically involves several genetic lesions, whose combined activity gives rise to cancer1. Here we analyse 1,148 patient-derived B-cell leukaemia (B-ALL) samples, and find that individual mutations do not promote leukaemogenesis unless they converge on one single oncogenic pathway that is characteristic of the differentiation stage of transformed B cells. Mutations that are not aligned with this central oncogenic driver activate divergent pathways and subvert transformation. Oncogenic lesions in B-ALL frequently mimic signalling through cytokine receptors at the pro-B-cell stage (via activation of the signal-transduction protein STAT5)2-4 or pre-B-cell receptors in more mature cells (via activation of the protein kinase ERK)5-8. STAT5- and ERK-activating lesions are found frequently, but occur together in only around 3% of cases (P = 2.2 × 10-16). Single-cell mutation and phospho-protein analyses reveal the segregation of oncogenic STAT5 and ERK activation to competing clones. STAT5 and ERK engage opposing biochemical and transcriptional programs that are orchestrated by the transcription factors MYC and BCL6, respectively. Genetic reactivation of the divergent (suppressed) pathway comes at the expense of the principal oncogenic driver and reverses transformation. Conversely, deletion of divergent pathway components accelerates leukaemogenesis. Thus, persistence of divergent signalling pathways represents a powerful barrier to transformation, while convergence on one principal driver defines a central event in leukaemia initiation. Pharmacological reactivation of suppressed divergent circuits synergizes strongly with inhibition of the principal oncogenic driver. Hence, reactivation of divergent pathways can be leveraged as a previously unrecognized strategy to enhance treatment responses.


Asunto(s)
Linfocitos B/citología , Linfocitos B/metabolismo , Transformación Celular Neoplásica , Leucemia de Células B/metabolismo , Leucemia de Células B/patología , Transducción de Señal , Animales , Linfocitos B/patología , Línea Celular Tumoral , Activación Enzimática , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Femenino , Humanos , Ratones , Proteína Tirosina Fosfatasa no Receptora Tipo 6/metabolismo , Proteínas Proto-Oncogénicas c-bcl-6/metabolismo , Proteínas Proto-Oncogénicas c-myc/metabolismo , Factor de Transcripción STAT5/metabolismo
4.
Int J Gynecol Pathol ; 43(2): 182-189, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-37406452

RESUMEN

Leiomyosarcoma (LMS) with osteoclast-like giant cells (OLGCs) is a rare entity with only 18 reported cases thus far. It is not known whether these OLGCs are a reactive or malignant component of LMS. Herein we describe the clinical, histologic, and molecular characteristics of 2 cases of LMS with OLGCs and perform a brief literature review. In 2 of our cases, the OLGCs, marked with CD68, had a low proliferation index with Ki67 and did not show diffuse positivity for smooth muscle markers by immunohistochemistry. By next-generation sequencing, one case harbored a clinically significant TP53 mutation, which has been reported in a significant subset of conventional LMSs. In this case, based on immunohistochemistry, OLGCs showed different molecular alterations as compared with LMS. Although we did not show a distinct immunophenotype or molecular profile for LMS with OLGCs, this study provides additional data on this rare entity.


Asunto(s)
Leiomiosarcoma , Neoplasias Pélvicas , Neoplasias Uterinas , Femenino , Humanos , Leiomiosarcoma/diagnóstico , Leiomiosarcoma/genética , Osteoclastos/patología , Neoplasias Uterinas/diagnóstico , Neoplasias Uterinas/genética , Neoplasias Uterinas/patología , Neoplasias Pélvicas/patología , Células Gigantes/patología
5.
Nature ; 558(7711): E5, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29849140

RESUMEN

In Fig. 3c of this Letter, the the effects of CRISPR-Cas9-mediated deletion of NR3C1, TXNIP and CNR2 in patient-derived B-lineage leukaemia cells were shown. For curves depicting NR3C1 (left graph), data s for TXNIP (middle graph) were inadvertently plotted. This figure has been corrected online, and the original Fig. 3c is shown as Supplementary Information to this Amendment for transparency. The error does not affect the conclusions of the Letter. In addition, Source Data files have been added for the Figs. 1-4 and Extended Data Figs. 1-10 of the original Letter.

6.
Nature ; 542(7642): 479-483, 2017 02 23.
Artículo en Inglés | MEDLINE | ID: mdl-28192788

RESUMEN

B-lymphoid transcription factors, such as PAX5 and IKZF1, are critical for early B-cell development, yet lesions of the genes encoding these transcription factors occur in over 80% of cases of pre-B-cell acute lymphoblastic leukaemia (ALL). The importance of these lesions in ALL has, until now, remained unclear. Here, by combining studies using chromatin immunoprecipitation with sequencing and RNA sequencing, we identify a novel B-lymphoid program for transcriptional repression of glucose and energy supply. Our metabolic analyses revealed that PAX5 and IKZF1 enforce a state of chronic energy deprivation, resulting in constitutive activation of the energy-stress sensor AMPK. Dominant-negative mutants of PAX5 and IKZF1, however, relieved this glucose and energy restriction. In a transgenic pre-B ALL mouse model, the heterozygous deletion of Pax5 increased glucose uptake and ATP levels by more than 25-fold. Reconstitution of PAX5 and IKZF1 in samples from patients with pre-B ALL restored a non-permissive state and induced energy crisis and cell death. A CRISPR/Cas9-based screen of PAX5 and IKZF1 transcriptional targets identified the products of NR3C1 (encoding the glucocorticoid receptor), TXNIP (encoding a glucose-feedback sensor) and CNR2 (encoding a cannabinoid receptor) as central effectors of B-lymphoid restriction of glucose and energy supply. Notably, transport-independent lipophilic methyl-conjugates of pyruvate and tricarboxylic acid cycle metabolites bypassed the gatekeeper function of PAX5 and IKZF1 and readily enabled leukaemic transformation. Conversely, pharmacological TXNIP and CNR2 agonists and a small-molecule AMPK inhibitor strongly synergized with glucocorticoids, identifying TXNIP, CNR2 and AMPK as potential therapeutic targets. Furthermore, our results provide a mechanistic explanation for the empirical finding that glucocorticoids are effective in the treatment of B-lymphoid but not myeloid malignancies. Thus, B-lymphoid transcription factors function as metabolic gatekeepers by limiting the amount of cellular ATP to levels that are insufficient for malignant transformation.


Asunto(s)
Linfocitos B/metabolismo , Metabolismo Energético/genética , Regulación Neoplásica de la Expresión Génica , Glucosa/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras B/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras B/metabolismo , Factores de Transcripción/metabolismo , Quinasas de la Proteína-Quinasa Activada por el AMP , Proteínas Quinasas Activadas por AMP/antagonistas & inhibidores , Adenosina Trifosfato/metabolismo , Animales , Linfocitos B/efectos de los fármacos , Carcinogénesis/genética , Proteínas Portadoras/agonistas , Proteínas Portadoras/metabolismo , Muerte Celular , Inmunoprecipitación de Cromatina , Ciclo del Ácido Cítrico , Modelos Animales de Enfermedad , Femenino , Glucocorticoides/farmacología , Glucocorticoides/uso terapéutico , Humanos , Factor de Transcripción Ikaros/metabolismo , Ratones , Ratones Transgénicos , Factor de Transcripción PAX5/deficiencia , Factor de Transcripción PAX5/genética , Factor de Transcripción PAX5/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras B/tratamiento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras B/patología , Proteínas Serina-Treonina Quinasas/metabolismo , Ácido Pirúvico/metabolismo , Receptor Cannabinoide CB2/agonistas , Receptor Cannabinoide CB2/metabolismo , Receptores de Glucocorticoides/metabolismo , Análisis de Secuencia de ARN
7.
Cytopathology ; 33(6): 707-715, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35869577

RESUMEN

BACKGROUND: The clinical performance of the Yokohama reporting system for breast cytology remains uncertain. METHODS: In this study, we retrospectively evaluated 318 breast fine needle aspirations (FNABs) from Los Angeles County Hospital over a five-year period, analysing data for breast cytology, histology, and radiology. RESULTS: Among 318 breast FNAB cases, 78.3% (249/318) were benign and 5.3% (17/318) malignant. Of 83 cases with follow-up histology, 14.5% (12/83) were insufficient, 66.3% (55/83) were benign, and 16.9% (17/83) were malignant. Of 55 benign cases, 61.8% (34/55) were fibroadenoma and 9 (9/55, 16.4%) were fibrocystic changes. Two cases were diagnosed as "atypical" but confirmed "benign" on core needle biopsy (CNB). No "suspicious" cases were found. Seventeen malignant cases were confirmed by CNB, including 70.6% (12/17) invasive ductal carcinoma, 11.8% (2/17) invasive lobular carcinoma, and one malignant phyllodes tumour. Receptor studies on cell blocks of three malignant cases showed concordant results with CNB results. In addition, 82.2% (148/180) of lesions with Breast Imaging-Reporting and Data System (BI-RADS) scores of 2 or 3 were benign and 92.3% (12/13) BI-RADS score 5 lesions were malignant on FNAB. Finally, 90% (67/74) of BI-RADS 4a lesions were benign, and 97% (36/37) of fibroadenomas were BI-RADS score 4a. CONCLUSION: This, by far the largest U.S. breast cytology study, showed 93.3% sensitivity, 100% specificity, 100% positive predictive value, and 98.2% negative predictive value for breast FNAB. Women with breast lesions of BI-RADS score 3 or less have a low risk of malignancy; FNAB would contribute to the reduction of excisional biopsies. FNAB can be considered as an initial diagnostic tool for BI-RADS 4 mass/lesions and satellite lesions, as well as for triaging patients.


Asunto(s)
Neoplasias de la Mama , Fibroadenoma , Biopsia con Aguja Fina , Mama/anomalías , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/patología , Femenino , Fibroadenoma/diagnóstico , Hospitales , Humanos , Hipertrofia , Estudios Retrospectivos , Sensibilidad y Especificidad
8.
Nature ; 521(7552): 357-61, 2015 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-25799995

RESUMEN

B cells are selected for an intermediate level of B-cell antigen receptor (BCR) signalling strength: attenuation below minimum (for example, non-functional BCR) or hyperactivation above maximum (for example, self-reactive BCR) thresholds of signalling strength causes negative selection. In ∼25% of cases, acute lymphoblastic leukaemia (ALL) cells carry the oncogenic BCR-ABL1 tyrosine kinase (Philadelphia chromosome positive), which mimics constitutively active pre-BCR signalling. Current therapeutic approaches are largely focused on the development of more potent tyrosine kinase inhibitors to suppress oncogenic signalling below a minimum threshold for survival. We tested the hypothesis that targeted hyperactivation--above a maximum threshold--will engage a deletional checkpoint for removal of self-reactive B cells and selectively kill ALL cells. Here we find, by testing various components of proximal pre-BCR signalling in mouse BCR-ABL1 cells, that an incremental increase of Syk tyrosine kinase activity was required and sufficient to induce cell death. Hyperactive Syk was functionally equivalent to acute activation of a self-reactive BCR on ALL cells. Despite oncogenic transformation, this basic mechanism of negative selection was still functional in ALL cells. Unlike normal pre-B cells, patient-derived ALL cells express the inhibitory receptors PECAM1, CD300A and LAIR1 at high levels. Genetic studies revealed that Pecam1, Cd300a and Lair1 are critical to calibrate oncogenic signalling strength through recruitment of the inhibitory phosphatases Ptpn6 (ref. 7) and Inpp5d (ref. 8). Using a novel small-molecule inhibitor of INPP5D (also known as SHIP1), we demonstrated that pharmacological hyperactivation of SYK and engagement of negative B-cell selection represents a promising new strategy to overcome drug resistance in human ALL.


Asunto(s)
Linfocitos B/metabolismo , Linfocitos B/patología , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/patología , Transducción de Señal , Secuencias de Aminoácidos/genética , Animales , Antígenos CD/metabolismo , Linfocitos B/efectos de los fármacos , Muerte Celular/efectos de los fármacos , Línea Celular Tumoral , Transformación Celular Neoplásica , Modelos Animales de Enfermedad , Resistencia a Antineoplásicos/efectos de los fármacos , Activación Enzimática/efectos de los fármacos , Femenino , Proteínas de Fusión bcr-abl/genética , Eliminación de Gen , Humanos , Inositol Polifosfato 5-Fosfatasas , Péptidos y Proteínas de Señalización Intracelular/agonistas , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Ratones , Ratones Endogámicos NOD , Ratones SCID , Fosfatidilinositol-3,4,5-Trifosfato 5-Fosfatasas , Monoéster Fosfórico Hidrolasas/antagonistas & inhibidores , Monoéster Fosfórico Hidrolasas/metabolismo , Molécula-1 de Adhesión Celular Endotelial de Plaqueta/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Células Precursoras de Linfocitos B/efectos de los fármacos , Células Precursoras de Linfocitos B/metabolismo , Células Precursoras de Linfocitos B/patología , Proteína Tirosina Fosfatasa no Receptora Tipo 6/deficiencia , Proteína Tirosina Fosfatasa no Receptora Tipo 6/genética , Proteína Tirosina Fosfatasa no Receptora Tipo 6/metabolismo , Proteínas Tirosina Quinasas/metabolismo , Receptores de Antígenos de Linfocitos B/deficiencia , Receptores de Antígenos de Linfocitos B/genética , Receptores de Antígenos de Linfocitos B/metabolismo , Receptores Inmunológicos/genética , Receptores Inmunológicos/metabolismo , Transducción de Señal/efectos de los fármacos , Quinasa Syk , Tirosina/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto
9.
Mediators Inflamm ; 2021: 9979032, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33967626

RESUMEN

Coronaviruses (CoVs) are enveloped and harbor an unusually large (30-32 kb) positive-strand linear RNA genome. Highly pathogenic coronaviruses cause severe acute respiratory syndrome (SARS) (SARS-CoV and SARS-CoV-2) and Middle East respiratory syndrome (MERS) (MERS-CoV) in humans. The coronavirus mouse hepatitis virus (MHV) infects mice and serves as an ideal model of viral pathogenesis, mainly because experiments can be conducted using animal-biosafety level-2 (A-BSL2) containment. Human thymosin beta-4 (Tß4), a 43-residue peptide with an acetylated N-terminus, is widely expressed in human tissues. Tß4 regulates actin polymerization and functions as an anti-inflammatory molecule and an antioxidant as well as a promoter of wound healing and angiogenesis. These activities led us to test whether Tß4 serves to treat coronavirus infections of humans. To test this possibility, here, we established a BALB/c mouse model of coronavirus infection using mouse CoV MHV-A59 to evaluate the potential protective effect of recombinant human Tß4 (rhTß4). Such a system can be employed under A-BSL2 containment instead of A-BSL3 that is required to study coronaviruses infectious for humans. We found that rhTß4 significantly increased the survival rate of mice infected with MHV-A59 through inhibiting virus replication, balancing the host's immune response, alleviating pathological damage, and promoting repair of the liver. These results will serve as the basis for further application of rhTß4 to the treatment of human CoV diseases such as COVID-19.


Asunto(s)
Infecciones por Coronavirus/tratamiento farmacológico , Virus de la Hepatitis Murina , Timosina/uso terapéutico , Animales , Anticuerpos Antivirales/sangre , Proteína C-Reactiva/análisis , Citocinas/sangre , Femenino , Humanos , Ratones , Ratones Endogámicos BALB C , Virus de la Hepatitis Murina/inmunología , ARN Viral/análisis , Proteínas Recombinantes/uso terapéutico , Replicación Viral/efectos de los fármacos
10.
Environ Geochem Health ; 43(3): 1287-1304, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32974884

RESUMEN

Aim to classify typical hot springs in Guizhou, China and their relevance to health. Assessing geochemical characters of typical hot springs of Guizhou and classifying through hierarchical cluster analysis, an epidemiologic study was conducted to analyze the correlation between hot spring types and health, which showed typical hot springs in Guizhou can be divided into two types, A and B. Type A is rich in fluorine, metasilicic acid, radon components and a large number of essential elements, such as Na, that the human body needs, with trace elements, such as Cr and V, that are essential or possibly essential. Type B is rich in fluorine, metasilicate, strontium components and a large number of essential elements, Ca, Mg, and S, with trace elements, Cu, Mn, Mo, Co, and Ni, that are essential or possibly essential. These hot springs' effects on the health of those bathing in them showed both types were associated with bone and joint diseases. Having bathed in hot springs during the past year was associated with skin symptoms and bone and joint symptoms, and having bathed within the past two weeks was linked to sleep quality and levels of appetite and energy. However, differences do exist between the correlation between the two types and some chronic diseases, with Type A hot springs significantly related to cardiovascular and cerebrovascular diseases and diabetes and Type B to hypertension. This classification of Guizhou's hot springs can guide the future development and use of hot spring physiotherapy.


Asunto(s)
Promoción de la Salud/métodos , Manantiales de Aguas Termales , Oligoelementos/análisis , Agua/química , China , Humanos
11.
Nat Immunol ; 9(8): 927-36, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18568028

RESUMEN

The transcription factor Ikaros is essential for B cell development. However, its molecular functions in B cell fate specification and commitment have remained elusive. We show here that the transcription factor EBF restored the generation of CD19(+) pro-B cells from Ikaros-deficient hematopoietic progenitors. Notably, these pro-B cells, despite having normal expression of the transcription factors EBF and Pax5, were not committed to the B cell fate. They also failed to recombine variable gene segments at the immunoglobulin heavy-chain locus. Ikaros promoted heavy-chain gene rearrangements by inducing expression of the recombination-activating genes as well as by controlling accessibility of the variable gene segments and compaction of the immunoglobulin heavy-chain locus. Thus, Ikaros is an obligate component of a network that regulates B cell fate commitment and immunoglobulin heavy-chain gene recombination.


Asunto(s)
Linfocitos B/fisiología , Genes de Inmunoglobulinas/genética , Factor de Transcripción Ikaros/metabolismo , Cadenas Pesadas de Inmunoglobulina/genética , VDJ Recombinasas/genética , Animales , Sitios de Unión , Diferenciación Celular , Línea Celular , Linaje de la Célula , Reordenamiento Génico/genética , Reordenamiento Génico/inmunología , Factor de Transcripción Ikaros/genética , Ratones
12.
Proc Natl Acad Sci U S A ; 114(47): 12548-12553, 2017 11 21.
Artículo en Inglés | MEDLINE | ID: mdl-29109286

RESUMEN

The circadian system regulates numerous physiological processes including immune responses. Here, we show that mice deficient of the circadian clock genes Cry1 and Cry2 [Cry double knockout (DKO)] develop an autoimmune phenotype including high serum IgG concentrations, serum antinuclear antibodies, and precipitation of IgG, IgM, and complement 3 in glomeruli and massive infiltration of leukocytes into the lungs and kidneys. Flow cytometry of lymphoid organs revealed decreased pre-B cell numbers and a higher percentage of mature recirculating B cells in the bone marrow, as well as increased numbers of B2 B cells in the peritoneal cavity of Cry DKO mice. The B cell receptor (BCR) proximal signaling pathway plays a critical role in autoimmunity regulation. Activation of Cry DKO splenic B cells elicited markedly enhanced tyrosine phosphorylation of cellular proteins compared with cells from control mice, suggesting that overactivation of the BCR-signaling pathway may contribute to the autoimmunity phenotype in the Cry DKO mice. In addition, the expression of C1q, the deficiency of which contributes to the pathogenesis of systemic lupus erythematosus, was significantly down-regulated in Cry DKO B cells. Our results suggest that B cell development, the BCR-signaling pathway, and C1q expression are regulated by circadian clock CRY proteins and that their dysregulation through loss of CRY contributes to autoimmunity.


Asunto(s)
Enfermedades Autoinmunes/inmunología , Autoinmunidad/genética , Linfocitos B/inmunología , Relojes Circadianos/inmunología , Criptocromos/inmunología , Animales , Anticuerpos Antinucleares/biosíntesis , Enfermedades Autoinmunes/genética , Enfermedades Autoinmunes/metabolismo , Enfermedades Autoinmunes/patología , Linfocitos B/metabolismo , Linfocitos B/patología , Relojes Circadianos/genética , Complemento C1q/genética , Criptocromos/deficiencia , Criptocromos/genética , Perfilación de la Expresión Génica , Regulación de la Expresión Génica/inmunología , Riñón/inmunología , Riñón/patología , Pulmón/inmunología , Pulmón/patología , Activación de Linfocitos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Receptores de Antígenos de Linfocitos B/genética , Receptores de Antígenos de Linfocitos B/inmunología , Transducción de Señal , Bazo/inmunología , Bazo/metabolismo , Bazo/patología
13.
Immunol Rev ; 263(1): 192-209, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25510278

RESUMEN

Pre-B cells within the bone marrow represent the normal counterpart for most acute lymphoblastic leukemia (ALL). During normal early B-cell development, survival and proliferation signals are dominated by cytokines, particularly interleukin-7 (IL-7) for murine developing B cells. With expression of a functional pre-B-cell receptor (BCR), cytokine signaling is attenuated and the tonic/autonomous pre-BCR signaling pathway provides proliferation as well as differentiation signals. In this review, we first describe checkpoint mechanisms during normal B-cell development and then discuss how genetic lesions in these pathways function as oncogenic mimicries and allow transformed pre-B cells to bypass checkpoint control. We focus on cytokine receptor signaling that is mimicked by activating lesions in receptor subunits or downstream mediators as well as aberrant activation of non-B lymphoid cytokine receptors. Furthermore, we describe the molecular switch from cytokine receptor to pre-BCR signaling, how this pathway is of particular importance for certain ALL subtypes, and how pre-BCR signaling is engaged by genetic lesions, such as BCR-ABL1. We discuss the transcriptional control mechanisms downstream of both cytokine- and pre-BCR signaling and how normal checkpoint control mechanisms are circumvented in pre-B ALL. Finally, we highlight new therapeutic concepts for targeted inhibition of oncogenic cytokine or pre-BCR signaling pathways.


Asunto(s)
Proteínas de Fusión bcr-abl/metabolismo , Receptores de Células Precursoras de Linfocitos B/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/inmunología , Células Precursoras de Linfocitos B/fisiología , Animales , Antineoplásicos/farmacología , Diferenciación Celular/efectos de los fármacos , Citocinas/metabolismo , Proteínas de Fusión bcr-abl/genética , Humanos , Ratones , Terapia Molecular Dirigida , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Transducción de Señal/efectos de los fármacos
15.
Blood ; 121(1): 148-55, 2013 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-23152540

RESUMEN

The Sox4 transcription factor mediates early B-cell differentiation. Compared with normal pre-B cells, SOX4 promoter regions in Ph(+) ALL cells are significantly hypomethylated. Loss and gain-of-function experiments identified Sox4 as a critical activator of PI3K/AKT and MAPK signaling in ALL cells. ChIP experiments confirmed that SOX4 binds to and transcriptionally activates promoters of multiple components within the PI3K/AKT and MAPK signaling pathways. Cre-mediated deletion of Sox4 had little effect on normal pre-B cells but compromised proliferation and viability of leukemia cells, which was rescued by BCL2L1 and constitutively active AKT and p110 PI3K. Consistent with these findings, high levels of SOX4 expression in ALL cells at the time of diagnosis predicted poor outcome in a pediatric clinical trial (COG P9906). Collectively, these studies identify SOX4 as a central mediator of oncogenic PI3K/AKT and MAPK signaling in ALL.


Asunto(s)
Regulación Leucémica de la Expresión Génica/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras B/genética , Factores de Transcripción SOXC/fisiología , Transducción de Señal/fisiología , Animales , Linfocitos B/efectos de los fármacos , Linfocitos B/metabolismo , Benzamidas , Supervivencia Celular/efectos de los fármacos , Niño , Metilación de ADN , Humanos , Mesilato de Imatinib , Estimación de Kaplan-Meier , Ratones , Ratones Endogámicos NOD , Ratones SCID , Estudios Multicéntricos como Asunto/estadística & datos numéricos , Proteínas de Neoplasias/antagonistas & inhibidores , Proteínas de Neoplasias/biosíntesis , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/fisiología , Piperazinas/farmacología , Piperazinas/uso terapéutico , Leucemia-Linfoma Linfoblástico de Células Precursoras B/tratamiento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras B/mortalidad , Leucemia-Linfoma Linfoblástico de Células Precursoras B/patología , Regiones Promotoras Genéticas , Modelos de Riesgos Proporcionales , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/uso terapéutico , Pirimidinas/farmacología , Pirimidinas/uso terapéutico , Quimera por Radiación , Ensayos Clínicos Controlados Aleatorios como Asunto/estadística & datos numéricos , Factores de Transcripción SOXC/biosíntesis , Factores de Transcripción SOXC/deficiencia , Factores de Transcripción SOXC/genética , Transducción de Señal/efectos de los fármacos , Células Tumorales Cultivadas/citología , Células Tumorales Cultivadas/efectos de los fármacos , Ensayo de Tumor de Célula Madre
16.
Hum Reprod ; 30(2): 380-91, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25505012

RESUMEN

STUDY QUESTION: How does the placenta protect the fetus from immune rejection by the mother? SUMMARY ANSWER: The placenta can produce IgG that is glycosylated at one of its Fab arms (asymmetric IgG; aIgG) which can interact with other antibodies and certain leukocytes to affect local immune reactions at the junction between the two genetically distinct entities. WHAT IS KNOWN ALREADY: The placenta can protect the semi-allogenic fetus from immune rejection by the immune potent mother. aIgG in serum is increased during pregnancy and returns to the normal range after giving birth. aIgG can react to antigens to form immune complexes which do not cause a subsequent immune effector reaction, including fixing complements, inducing cytotoxicity and phagocytosis, and therefore has been called 'blocking antibody'. STUDY DESIGN, SIZE, DURATION: Eighty-eight human placentas, four trophoblast cell lines (TEV-1, JAR, JEG and BeWo), primary culture of human placental trophoblasts and a gene knock-out mouse model were investigated in this study. PARTICIPANTS/MATERIALS, SETTING, METHODS: The general approach included the techniques of cell culture, immunohistochemistry, in situ hybridization, immuno-electron microscopy, western blot, quantitative PCR, protein isolation, glycosylation analysis, enzyme digestion, gene sequencing, mass spectrophotometry, laser-guided microdissection, enzyme-linked immunosorbent assay, pulse chase assay, double and multiple staining to analyze protein and DNA and RNA analysis at the cellular and molecular levels. MAIN RESULTS AND THE ROLE OF CHANCE: Three major discoveries were made: (i) placental trophoblasts and endothelial cells are capable of producing IgG, a significant portion of which is aberrantly glycosylated at one of its Fab arms to form aIgG; (ii) the asymmetrically glycosylated IgG produced by trophoblasts and endothelial cells can react to immunoglobulin molecules of human, rat, mouse, goat and rabbit at the Fc portion; (iii) asymmetrically glycosylated IgG can react to certain leukocytes in the membrane and cytoplasm, while symmetric IgG from the placenta does not have this property. LIMITATIONS, REASONS FOR CAUTION: Most of the experiments were performed in vitro. The proposed mechanism calls for verification in normal and abnormal pregnancy. WIDER IMPLICATIONS OF THE FINDINGS: This study identified a number of new phenomena suggesting that aIgG produced by the placenta would be able to react to detrimental antibodies and leukocytes and interfere with their immune reactions against the placenta and the fetus. This opens a new dimension for further studies on pregnancy physiology and immunology. Should the mechanism proposed here be confirmed, it will have a direct impact on our understanding of the physiology and pathology of human reproduction and offer new possibilities for the treatment of many diseases including spontaneous abortion, infertility and pre-eclampsia. It also sheds light on the mechanism of immune evasion in general including that of cancer.


Asunto(s)
Fragmentos Fab de Inmunoglobulinas/metabolismo , Inmunoglobulina G/metabolismo , Inmunomodulación , Modelos Inmunológicos , Placenta/inmunología , Adulto , Animales , Especificidad de Anticuerpos , Línea Celular , Células Cultivadas , Cruzamientos Genéticos , Endotelio Vascular/citología , Endotelio Vascular/inmunología , Endotelio Vascular/metabolismo , Endotelio Vascular/ultraestructura , Femenino , Humanos , Fragmentos Fab de Inmunoglobulinas/análisis , Inmunoglobulina G/análisis , Leucocitos/citología , Leucocitos/inmunología , Leucocitos/metabolismo , Leucocitos/ultraestructura , Ratones Noqueados , Microscopía Inmunoelectrónica , Placenta/citología , Placenta/metabolismo , Placenta/ultraestructura , Placentación , Embarazo , Trofoblastos/citología , Trofoblastos/inmunología , Trofoblastos/metabolismo , Trofoblastos/ultraestructura
17.
Lab Invest ; 94(11): 1283-95, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25264708

RESUMEN

The liver has the extraordinary properties of regeneration and immune tolerance; however, the mechanisms governing these abilities are poorly understood. To address these questions, we examined the possible expression of immunoglobulins in the human and rat liver and the relationship of IgG expression to hepatocyte proliferation, metastasis, apoptosis and immune tolerance. Immunohistochemistry, in situ hybridization, laser-guided microdissection and reverse transcription-PCR were performed to examine the expression of IgG in normal human and rat liver, severe combined immunodeficient mouse (SCID) liver and human liver cancers and corresponding cell lines. Small interfering RNA (siRNA) was transfected into cultured hepatocarcinoma cells to downregulate the expression of IgG heavy chain genes. Cell proliferation and apoptosis were assayed with flow cytometry. Cell metastasis was assayed with a Transwell cell assay. Partial hepatectomy (70%) was performed in rats to examine the relationship between hepatocyte IgG and hepatocyte proliferation. IgG, together with essential enzymes for its synthesis, were expressed in the cytoplasm of hepatocytes of normal adult human and hepatoma patients and rat livers, SCID mouse liver and BRL-3A, L-02 and HepG-2 cell lines. Downregulation of IgG inhibited cell proliferation and metastasis and promoted apoptosis. Postsurgery livers expressed significantly more IgG than the livers before surgery and decreased to the original levels when hepatocytes stopped regeneration. IgA and IgM but not IgD and IgE were also positive in hepatocytes. Our findings demonstrate that normal and malignant hepatocytes are capable of synthesizing immunoglobulin, which has important roles in hepatocyte proliferation, apoptosis and cancer growth with profound clinical implications.


Asunto(s)
Carcinoma Hepatocelular/inmunología , Hepatocitos/metabolismo , Inmunoglobulina G/biosíntesis , Neoplasias Hepáticas Experimentales/inmunología , Regeneración Hepática/inmunología , Animales , Apoptosis , Regulación hacia Abajo , Células Hep G2 , Hepatectomía , Humanos , Inmunoglobulina A/metabolismo , Inmunoglobulina M/metabolismo , Hígado/inmunología , Hígado/metabolismo , Hígado/cirugía , Masculino , Ratones SCID , Metástasis de la Neoplasia , ARN Mensajero/metabolismo , ARN Interferente Pequeño , Ratas Sprague-Dawley
18.
Biol Reprod ; 91(5): 128, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25273527

RESUMEN

The placenta is known to protect the fetus from infection and maternal rejection. In a previous study, we demonstrated that placental trophoblasts can synthesize immunoglobulin G (IgG). In this study, we investigated the distribution of immunoglobulins (IgG, IgM, and IgA), IgG receptors (FcRn and FcgammaRIII), and complement proteins in placental trophoblasts at the ultrastructural level. In addition, we studied the mRNA expression of IgG1 heavy chain (IGHG1), recombination activating gene 1 (RAG1), RAG2, and activation-induced cytidine deaminase (AID) with nested RT-PCR in primary cultured trophoblasts. The mRNA transcripts of IGHG1, RAG1, RAG2, and AID were all identified in primary trophoblasts, further establishing the IgG-producing capacity of trophoblasts. At the ultrastructural level with colloidal gold-labeled antibodies, IgG was found to be distributed in two distinct locations in syncytiotrophoblasts. For one, it was colocalized with FcRn in endosome displaying low electron density, and for the other it was colocalized with complement C1q in medium-electron density irregular structures that have not been reported previously. This characteristic distribution suggests that IgG is likely processed through two molecular mechanisms in syncytiotrophoblasts: receptor-bound transportation across the syncytiotrophoblast and formation of immune complexes with locally produced IgG. The latter mechanism is probably aimed at neutralizing detrimental maternal anti-paternal major histocompatibility complex antibodies. Our findings support the hypothesis that placenta-produced IgG can selectively react with maternal anti-fetus antibodies and provide a mechanism of fetomaternal tolerance to protect the fetus from maternal immune rejection.


Asunto(s)
Inmunoglobulina G/inmunología , Inmunoglobulina G/metabolismo , Placenta/inmunología , Placenta/metabolismo , Células Cultivadas , Femenino , Humanos , Inmunohistoquímica , Microscopía Electrónica , Placenta/ultraestructura , Embarazo , Distribución Tisular , Trofoblastos/metabolismo , Trofoblastos/ultraestructura
19.
Clin Genitourin Cancer ; 22(2): 347-353, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38195301

RESUMEN

BACKGROUND: CD70 is commonly overexpressed in renal cell carcinoma and is minimally expressed in normal human tissue, making it a potential therapeutic target for patients with advanced renal cell carcinoma. The expression frequency of CD70 in metastatic renal cell carcinoma is not well established. MATERIALS AND METHODS: We assessed CD70 immunohistochemistry in 391 primary renal tumors and 72 metastatic renal cell carcinomas on a tissue microarray including 26 sets of paired primary and metastatic tumors. RESULTS: CD70 was frequently overexpressed in clear cell carcinoma, with a significantly lower expression rate in papillary renal cell carcinoma (P < .0001). No expression of CD70 was detected in other types of renal tumors and normal renal parenchyma. In clear cell renal cell carcinoma, CD70 expression was significantly correlated with hypoxia pathway proteins, corroborating with a recent study suggesting that CD70 is a downstream target gene of hypoxia-inducible factor. While higher expression levels were observed in males and non-Caucasians, CD70 expression was not associated with tumor grade, sarcomatoid differentiation, stage, or cancer-specific survival. Further, analysis of 26 paired primary and metastatic tumors from same individuals revealed a concordance rate of 85%. CONCLUSION: Our findings validated CD70 as a promising therapeutic target for patients with metastatic clear cell renal cell carcinoma. The utility of primary tumor tissue as surrogate samples for metastatic clear cell carcinoma awaits future CD70-targeted clinical trials.


Asunto(s)
Carcinoma de Células Renales , Neoplasias Renales , Masculino , Humanos , Carcinoma de Células Renales/tratamiento farmacológico , Neoplasias Renales/tratamiento farmacológico , Riñón/patología , Hipoxia , Biomarcadores de Tumor , Ligando CD27/metabolismo
20.
Innovation (Camb) ; 5(3): 100603, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38745762

RESUMEN

The vaccine-induced innate immune response is essential for the generation of an antibody response. To date, how Ad5-vectored vaccines are influenced by preexisting anti-Ad5 antibodies during activation of the early immune response remains unclear. Here, we investigated the specific alterations in GP1,2-specific IgG-related elements of the early immune response at the genetic, molecular, and cellular levels on days 0, 1, 3, and 7 after Ad5-EBOV vaccination. In a causal multiomics analysis, distinct early immune responses associated with GP1,2-specific IgG were observed in Ad5-EBOV recipients with a low level of preexisting anti-Ad5 antibodies. This study revealed the correlates of the Ad5-EBOV-induced IgG response and provided mechanistic evidence for overcoming preexisting Ad5 immunity during the administration of Ad5-vectored vaccines.

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