Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 871
Filtrar
1.
Sci Rep ; 14(1): 9128, 2024 04 21.
Artículo en Inglés | MEDLINE | ID: mdl-38644382

RESUMEN

Hepatocellular carcinoma (HCC) is one of the most common malignant tumors worldwide. Macrophage-mediated innate immune responses play a crucial role in tumor development. This study revealed the mechanism of SHP-1 in regulating HCC progression. SHP-1 inhibits tumour development in vivo. Increasing SHP-1 expression in macrophages promotes the expression of p-SHP-1, SHP2, and p-SHP-2. In macrophages GM-CSF recruits SHP-2 to the GM-CSF receptor GM-CSFR induces p-SHP-2 dephosphorylation. GM-CSF recruits p-SHP-2 for dephosphorylation by up-regulating HoxA10HOXA10 activates the transcription of TGFß2 by interacting with tandem cis-elements in the promoter thereby regulating the proliferation and migration of liver cancer cells. GM-CSF inhibits SHP-1 regulation of p-SHP-1, SHP2, and p-SHP-2 in macrophages. Detailed studies have shown that SHP-1 regulates SHP2 expression, and SHP-1 and SHP2 are involved in macrophage M2 polarisation. SHP-1 inhibits HOXA10 and TGFß2 which in turn regulates the expression of the migration-associated proteins, MMP2/9, and the migration of hepatocellular carcinoma cells. Overexpression of SHP-1 inhibits macrophage M2 polarisation via the p-STAT3/6 signalling pathway Classical markers arginase-1, CD206, CD163 and regulate the expression of M2 polarisation cytokines IL-4 and IL-10. In addition, hypoxia-induced ROS inhibited SHP-1 regulation by suppressing the expression of p-SHP-1. The combined effect of GM-CSF and ROS significantly increased p-HOXA10/TGFß2 and macrophage M2 polarisation, and the regulatory effect of ROS was significantly suppressed by GM-CSF knockdown. These findings suggest that increasing the expression of tyrosine phosphatase SHP-1 can inhibit hepatocellular carcinoma progression by modulating the SHP2/GM-CSF pathway in TAM and thus inhibit the progression of hepatocellular carcinoma.


Asunto(s)
Carcinoma Hepatocelular , Factor Estimulante de Colonias de Granulocitos y Macrófagos , Neoplasias Hepáticas , Macrófagos , Proteína Tirosina Fosfatasa no Receptora Tipo 11 , Proteína Tirosina Fosfatasa no Receptora Tipo 6 , Transducción de Señal , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/genética , Proteína Tirosina Fosfatasa no Receptora Tipo 6/metabolismo , Proteína Tirosina Fosfatasa no Receptora Tipo 6/genética , Factor Estimulante de Colonias de Granulocitos y Macrófagos/metabolismo , Proteína Tirosina Fosfatasa no Receptora Tipo 11/metabolismo , Proteína Tirosina Fosfatasa no Receptora Tipo 11/genética , Humanos , Animales , Macrófagos/metabolismo , Macrófagos/inmunología , Ratones , Progresión de la Enfermedad , Línea Celular Tumoral , Proliferación Celular , Movimiento Celular , Regulación Neoplásica de la Expresión Génica
2.
Genes (Basel) ; 15(4)2024 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-38674380

RESUMEN

BACKGROUND: Noonan syndrome (NS)/Noonan syndrome with multiple lentigines (NSML) is commonly characterized by distinct facial features, a short stature, cardiac problems, and a developmental delay of variable degrees. However, as many as 50% of individuals diagnosed with NS/NSML have a mildly affected parent or relative due to variable expressivity and possibly incomplete penetrance of the disorder, and those who are recognized to have NS only after a diagnosis are established in a more obviously affected index case. METHODS: In order to collect intergenerational data reported from previous studies, electronic journal databases containing information on the molecular genetics of PTPN11 were searched from 2000 to 2022. RESULTS: We present a case of a proband with a PTPN11 variant (c.1492C > T/p.Arg498Trp) inherited from an asymptomatic father, displaying only mild intellectual disability without classical symptoms of NS. Among our cases and the reported NS cases caused by the PTPN11 p.Arg498Trp variant, cardiac abnormalities (6/11), facial dysmorphism (7/11), skin pigmentation (4/11), growth problems (4/11), and sensorineural hearing loss (2/11) have been observed. NS/NSML patients with the PTPN11 p.Arg498Trp variant tend to exhibit relatively lower frequencies of skin pigmentation, facial dysmorphism and cardiac abnormalities and mild symptoms compared to those carrying any other mutated PTPN11. CONCLUSIONS: Paternally inherited NS/NSML caused by a PTPN11 p.Arg498Trp variant, including our cases, may exhibit relatively lower frequencies of abnormal features and mild symptoms. This could be ascribed to potential gene-gene interactions, gene-environment interactions, the gender and phenotype of the transmitting parent, or ethnic differences that influence the clinical phenotype.


Asunto(s)
Síndrome de Noonan , Proteína Tirosina Fosfatasa no Receptora Tipo 11 , Humanos , Proteína Tirosina Fosfatasa no Receptora Tipo 11/genética , Masculino , Síndrome de Noonan/genética , Herencia Paterna/genética , Fenotipo , Femenino , Linaje
3.
Proc Natl Acad Sci U S A ; 121(18): e2316819121, 2024 04 30.
Artículo en Inglés | MEDLINE | ID: mdl-38657042

RESUMEN

Posttranslational modifications regulate the properties and abundance of synaptic α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors that mediate fast excitatory synaptic transmission and synaptic plasticity in the central nervous system. During long-term depression (LTD), protein tyrosine phosphatases (PTPs) dephosphorylate tyrosine residues in the C-terminal tail of AMPA receptor GluA2 subunit, which is essential for GluA2 endocytosis and group I metabotropic glutamate receptor (mGluR)-dependent LTD. However, as a selective downstream effector of mGluRs, the mGluR-dependent PTP responsible for GluA2 tyrosine dephosphorylation remains elusive at Schaffer collateral (SC)-CA1 synapses. In the present study, we find that mGluR5 stimulation activates Src homology 2 (SH2) domain-containing phosphatase 2 (SHP2) by increasing phospho-Y542 levels in SHP2. Under steady-state conditions, SHP2 plays a protective role in stabilizing phospho-Y869 of GluA2 by directly interacting with GluA2 phosphorylated at Y869, without affecting GluA2 phospho-Y876 levels. Upon mGluR5 stimulation, SHP2 dephosphorylates GluA2 at Y869 and Y876, resulting in GluA2 endocytosis and mGluR-LTD. Our results establish SHP2 as a downstream effector of mGluR5 and indicate a dual action of SHP2 in regulating GluA2 tyrosine phosphorylation and function. Given the implications of mGluR5 and SHP2 in synaptic pathophysiology, we propose SHP2 as a promising therapeutic target for neurodevelopmental and autism spectrum disorders.


Asunto(s)
Endocitosis , Depresión Sináptica a Largo Plazo , Proteína Tirosina Fosfatasa no Receptora Tipo 11 , Receptores AMPA , Receptores de Glutamato Metabotrópico , Receptores AMPA/metabolismo , Animales , Fosforilación , Endocitosis/fisiología , Depresión Sináptica a Largo Plazo/fisiología , Receptores de Glutamato Metabotrópico/metabolismo , Proteína Tirosina Fosfatasa no Receptora Tipo 11/metabolismo , Proteína Tirosina Fosfatasa no Receptora Tipo 11/genética , Ratas , Tirosina/metabolismo , Receptor del Glutamato Metabotropico 5/metabolismo , Sinapsis/metabolismo , Ratones , Humanos , Neuronas/metabolismo
4.
Genes (Basel) ; 15(3)2024 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-38540404

RESUMEN

Noonan syndrome is a group of diseases with a similar clinical picture, consisting of 16 diseases caused by mutations in 15 genes. According to the literature, approximately half of all cases are attributed to Noonan syndrome type 1, NSML, caused by mutations in the PTPN11 gene. We analyzed 456 unrelated probands using a gene panel NGS, and in 206 cases, the cause of the disease was identified. Approximately half of the cases (107) were caused by variants in the PTPN11 gene, including three previously undescribed variants, one of which was classified as VOUS, and the other two as LP causative complex alleles. Frequent variants of the PTPN11 gene characteristics for Russian patients were identified, accounting for more than 38% (c.922A>G p.Asn308Asp, c.417G>C p.Glu139Asp, c.1403C>T p.Thr468Met) of all cases with mutations in the PTPN11 gene. A comparative characterization of frequent variants of the PTPN11 gene in different populations is shown. The most common features of Noonan syndrome in the studied sample were facial dysmorphisms and cardiovascular system abnormalities. A lower representation of patients with growth delay was observed compared to previously described samples.


Asunto(s)
Síndrome de Noonan , Humanos , Síndrome de Noonan/genética , Mutación , Alelos , Federación de Rusia , Proteína Tirosina Fosfatasa no Receptora Tipo 11/genética
5.
JCI Insight ; 9(8)2024 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-38451719

RESUMEN

Mesenchymal stem cells (MSCs), suffering from diverse gene hits, undergo malignant transformation and aberrant osteochondral differentiation. Src homology region 2-containing protein tyrosine phosphatase 2 (SHP2), a nonreceptor protein tyrosine phosphatase, regulates multicellular differentiation, proliferation, and transformation. However, the role of SHP2 in MSC fate determination remains unclear. Here, we showed that MSCs bearing the activating SHP2E76K mutation underwent malignant transformation into sarcoma stem-like cells. We revealed that the SHP2E76K mutation in mouse MSCs led to hyperactive mitochondrial metabolism by activating mitochondrial complexes I and III. Inhibition of complexes I and III prevented hyperactive mitochondrial metabolism and malignant transformation of SHP2E76K MSCs. Mechanistically, we verified that SHP2 underwent liquid-liquid phase separation (LLPS) in SHP2E76K MSCs. SHP2 LLPS led to its dissociation from complexes I and III, causing their hyperactivation. Blockade of SHP2 LLPS by LLPS-defective mutations or allosteric inhibitors suppressed complex I and III hyperactivation as well as malignant transformation of SHP2E76K MSCs. These findings reveal that complex I and III hyperactivation driven by SHP2 LLPS promotes malignant transformation of SHP2E76K MSCs and suggest that inhibition of SHP2 LLPS could be a potential therapeutic target for the treatment of activated SHP2-associated cancers.


Asunto(s)
Transformación Celular Neoplásica , Células Madre Mesenquimatosas , Mitocondrias , Proteína Tirosina Fosfatasa no Receptora Tipo 11 , Proteína Tirosina Fosfatasa no Receptora Tipo 11/metabolismo , Proteína Tirosina Fosfatasa no Receptora Tipo 11/genética , Células Madre Mesenquimatosas/metabolismo , Animales , Ratones , Mitocondrias/metabolismo , Transformación Celular Neoplásica/genética , Transformación Celular Neoplásica/metabolismo , Humanos , Mutación , Diferenciación Celular , Separación de Fases
6.
J Neurosci ; 44(17)2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38471782

RESUMEN

Cytoplasmic protein tyrosine phosphatase nonreceptor type 11 (PTPN11) and Drosophila homolog Corkscrew (Csw) regulate the mitogen-activated protein kinase (MAPK) pathway via a conserved autoinhibitory mechanism. Disease-causing loss-of-function (LoF) and gain-of-function (GoF) mutations both disrupt this autoinhibition to potentiate MAPK signaling. At the Drosophila neuromuscular junction glutamatergic synapse, LoF/GoF mutations elevate transmission strength and reduce activity-dependent synaptic depression. In both sexes of LoF/GoF mutations, the synaptic vesicles (SV)-colocalized synapsin phosphoprotein tether is highly elevated at rest, but quickly reduced with stimulation, suggesting a larger SV reserve pool with greatly heightened activity-dependent recruitment. Transmission electron microscopy of mutants reveals an elevated number of SVs clustered at the presynaptic active zones, suggesting that the increased vesicle availability is causative for the elevated neurotransmission. Direct neuron-targeted extracellular signal-regulated kinase (ERK) GoF phenocopies both increased local presynaptic MAPK/ERK signaling and synaptic transmission strength in mutants, confirming the presynaptic regulatory mechanism. Synapsin loss blocks this elevation in both presynaptic PTPN11 and ERK mutants. However, csw null mutants cannot be rescued by wild-type Csw in neurons: neurotransmission is only rescued by expressing Csw in both neurons and glia simultaneously. Nevertheless, targeted LoF/GoF mutations in either neurons or glia alone recapitulate the elevated neurotransmission. Thus, PTPN11/Csw mutations in either cell type are sufficient to upregulate presynaptic function, but a dual requirement in neurons and glia is necessary for neurotransmission. Taken together, we conclude that PTPN11/Csw acts in both neurons and glia, with LoF and GoF similarly upregulating MAPK/ERK signaling to enhance presynaptic Synapsin-mediated SV trafficking.


Asunto(s)
Proteínas de Drosophila , Sistema de Señalización de MAP Quinasas , Neuroglía , Neuronas , Terminales Presinápticos , Proteína Tirosina Fosfatasa no Receptora Tipo 11 , Sinapsinas , Transmisión Sináptica , Vesículas Sinápticas , Animales , Femenino , Masculino , Animales Modificados Genéticamente , Drosophila , Proteínas de Drosophila/metabolismo , Proteínas de Drosophila/genética , Sistema de Señalización de MAP Quinasas/fisiología , Mutación , Neuroglía/metabolismo , Neuroglía/fisiología , Unión Neuromuscular/metabolismo , Unión Neuromuscular/fisiología , Neuronas/metabolismo , Neuronas/fisiología , Terminales Presinápticos/metabolismo , Terminales Presinápticos/fisiología , Proteína Tirosina Fosfatasa no Receptora Tipo 11/metabolismo , Proteína Tirosina Fosfatasa no Receptora Tipo 11/genética , Sinapsinas/metabolismo , Sinapsinas/genética , Transmisión Sináptica/fisiología , Vesículas Sinápticas/metabolismo
7.
Rinsho Ketsueki ; 65(2): 63-68, 2024.
Artículo en Japonés | MEDLINE | ID: mdl-38447999

RESUMEN

A 28-year-old man was diagnosed with acute myelomonocytic leukemia. He achieved complete remission (CR) after two cycles of induction therapy. However, after consolidation therapy, bone marrow aspiration performed to prepare for allogeneic hematopoietic stem cell transplantation revealed disease relapse. Companion diagnostics confirmed the presence of the FLT3-ITD mutation. The patient received gilteritinib monotherapy and achieved CR. Subsequently, he underwent unrelated allogeneic bone marrow transplantation. One year after transplantation, the patient relapsed, and gilteritinib was resumed. However, the leukemia progressed, and panel sequencing using a next-generation sequencer showed that the FLT3-ITD mutation disappeared. A mutation in PTPN11, which regulates the RAS/MAPK signaling pathway, was also detected. Gilteritinib was discontinued, and the patient achieved CR with salvage chemotherapy. He underwent related haploidentical peripheral blood stem cell transplantation but died of relapse. This was a case in which genetic analysis revealed clonal transition and acquisition of resistance to treatment.


Asunto(s)
Leucemia Mieloide Aguda , Masculino , Humanos , Adulto , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/terapia , Compuestos de Anilina , Pirazinas , Enfermedad Crónica , Mutación , Respuesta Patológica Completa , Tirosina Quinasa 3 Similar a fms/genética , Proteína Tirosina Fosfatasa no Receptora Tipo 11/genética
8.
Front Immunol ; 15: 1340726, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38504984

RESUMEN

Encoded by PTPN11, the Src-homology 2 domain-containing phosphatase 2 (SHP2) integrates signals from various membrane-bound receptors such as receptor tyrosine kinases (RTKs), cytokine and integrin receptors and thereby promotes cell survival and proliferation. Activating mutations in the PTPN11 gene may trigger signaling pathways leading to the development of hematological malignancies, but are rarely found in solid tumors. Yet, aberrant SHP2 expression or activation has implications in the development, progression and metastasis of many solid tumor entities. SHP2 is involved in multiple signaling cascades, including the RAS-RAF-MEK-ERK-, PI3K-AKT-, JAK-STAT- and PD-L1/PD-1- pathways. Although not mutated, activation or functional requirement of SHP2 appears to play a relevant and context-dependent dichotomous role. This mostly tumor-promoting and infrequently tumor-suppressive role exists in many cancers such as gastrointestinal tumors, pancreatic, liver and lung cancer, gynecological entities, head and neck cancers, prostate cancer, glioblastoma and melanoma. Recent studies have identified SHP2 as a potential biomarker for the prognosis of some solid tumors. Based on promising preclinical work and the advent of orally available allosteric SHP2-inhibitors early clinical trials are currently investigating SHP2-directed approaches in various solid tumors, either as a single agent or in combination regimes. We here provide a brief overview of the molecular functions of SHP2 and collate current knowledge with regard to the significance of SHP2 expression and function in different solid tumor entities, including cells in their microenvironment, immune escape and therapy resistance. In the context of the present landscape of clinical trials with allosteric SHP2-inhibitors we discuss the multitude of opportunities but also limitations of a strategy targeting this non-receptor protein tyrosine phosphatase for treatment of solid tumors.


Asunto(s)
Neoplasias Pulmonares , Fosfatidilinositol 3-Quinasas , Masculino , Humanos , Transducción de Señal , Mutación con Ganancia de Función , Tirosina , Microambiente Tumoral , Proteína Tirosina Fosfatasa no Receptora Tipo 11/genética
10.
Sci Signal ; 17(817): eadg4422, 2024 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-38166031

RESUMEN

Thousand-and-one-amino acid kinase 3 (TAOK3) is a serine and threonine kinase that belongs to the STE-20 family of kinases. Its absence reduces T cell receptor (TCR) signaling and increases the interaction of the tyrosine phosphatase SHP-1, a major negative regulator of proximal TCR signaling, with the kinase LCK, a component of the core TCR signaling complex. Here, we used mouse models and human cell lines to investigate the mechanism by which TAOK3 limits the interaction of SHP-1 with LCK. The loss of TAOK3 decreased the survival of naïve CD4+ T cells by dampening the transmission of tonic and ligand-dependent TCR signaling. In mouse T cells, Taok3 promoted the secretion of interleukin-2 (IL-2) in response to TCR activation in a manner that depended on Taok3 gene dosage and on Taok3 kinase activity. TCR desensitization in Taok3-/- T cells was caused by an increased abundance of Shp-1, and pharmacological inhibition of Shp-1 rescued the activation potential of these T cells. TAOK3 phosphorylated threonine-394 in the phosphatase domain of SHP-1, which promoted its ubiquitylation and proteasomal degradation. The loss of TAOK3 had no effect on the abundance of SHP-2, which lacks a residue corresponding to SHP-1 threonine-394. Modulation of SHP-1 abundance by TAOK3 thus serves as a rheostat for TCR signaling and determines the activation threshold of T lymphocytes.


Asunto(s)
Proteínas Serina-Treonina Quinasas , Receptores de Antígenos de Linfocitos T , Linfocitos T , Animales , Humanos , Ratones , Proteína Tirosina Quinasa p56(lck) Específica de Linfocito , Fosforilación , Proteínas Serina-Treonina Quinasas/metabolismo , Proteína Tirosina Fosfatasa no Receptora Tipo 11/genética , Proteína Tirosina Fosfatasa no Receptora Tipo 11/metabolismo , Proteína Tirosina Fosfatasa no Receptora Tipo 6/genética , Proteína Tirosina Fosfatasa no Receptora Tipo 6/metabolismo , Receptores de Antígenos de Linfocitos T/genética , Receptores de Antígenos de Linfocitos T/metabolismo , Linfocitos T/metabolismo , Treonina/metabolismo
12.
Biochemistry ; 63(3): 273-281, 2024 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-38251939

RESUMEN

Src-homology-2-domain-containing PTP-2 (SHP2) is a widely expressed signaling enzyme whose misregulation is associated with multiple human pathologies. SHP2's enzymatic activity is controlled by a conformational equilibrium between its autoinhibited ("closed") state and its activated ("open") state. Although SHP2's closed state has been extensively characterized, the putative structure of its open form has only been revealed in the context of a highly activated mutant (E76K), and no systematic studies of the biochemical determinants of SHP2's open-state stabilization have been reported. To identify amino-acid interactions that are critical for stabilizing SHP2's active state, we carried out a mutagenic study of residues that lie at potentially important interdomain interfaces of the open conformation. The open/closed equilibria of the mutants were evaluated, and we identified several interactions that contribute to the stabilization of SHP2's open state. In particular, our findings establish that an ion pair between glutamate 249 on SHP2's PTP domain and arginine 111 on an interdomain loop is the key determinant of SHP2's open-state stabilization. Mutations that disrupt the R111/E249 ion pair substantially shift SHP2's open/closed equilibrium to the closed state, even compared to wild-type SHP2's basal-state equilibrium, which strongly favors the closed state. To the best of our knowledge, the ion-pair variants uncovered in this study are the first known SHP2 mutants in which autoinhibition is augmented with respect to the wild-type protein. Such "hyperinhibited" mutants may provide useful tools for signaling studies that investigate the connections between SHP2 inhibition and the suppression of human disease progression.


Asunto(s)
Proteína Tirosina Fosfatasa no Receptora Tipo 11 , Transducción de Señal , Humanos , Mutación , Proteína Tirosina Fosfatasa no Receptora Tipo 11/química , Proteína Tirosina Fosfatasa no Receptora Tipo 11/genética , Proteína Tirosina Fosfatasa no Receptora Tipo 11/metabolismo , Dominios Homologos src
13.
Cell Mol Life Sci ; 81(1): 64, 2024 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-38280930

RESUMEN

Silenced protein tyrosine phosphatase receptor type R (PTPRR) participates in mitogen-activated protein kinase (MAPK) signaling cascades during the genesis and development of tumors. Rat sarcoma virus (Ras) genes are frequently mutated in lung adenocarcinoma, thereby resulting in hyperactivation of downstream MAPK signaling. However, the molecular mechanism manipulating the regulation and function of PTPRR in RAS-mutant lung adenocarcinoma is not known. Patient records collected from the Cancer Genome Atlas and Gene Expression Omnibus showed that silenced PTPRR was positively correlated with the prognosis. Exogenous expression of PTPRR suppressed the proliferation and migration of lung cancer cells. PTPRR expression and Src homology 2 containing protein tyrosine phosphatase 2 (SHP2) inhibition acted synergistically to control ERK1/2 phosphorylation in RAS-driven lung cancer cells. Chromatin immunoprecipitation assay revealed that HDAC inhibition induced enriched histone acetylation in the promoter region of PTPRR and recovered PTPRR transcription. The combination of the HDAC inhibitor SAHA and SHP2 inhibitor SHP099 suppressed the progression of lung cancer markedly in vitro and in vivo. Therefore, we revealed the epigenetic silencing mechanism of PTPRR and demonstrated that combination therapy targeting HDAC and SHP2 might represent a novel strategy to treat RAS-mutant lung cancer.


Asunto(s)
Adenocarcinoma del Pulmón , Neoplasias Pulmonares , Humanos , Histonas/metabolismo , Acetilación , Adenocarcinoma del Pulmón/genética , Neoplasias Pulmonares/patología , Proteína Tirosina Fosfatasa no Receptora Tipo 11/genética , Proteína Tirosina Fosfatasa no Receptora Tipo 11/metabolismo , Línea Celular Tumoral , Proteínas Tirosina Fosfatasas Clase 7 Similares a Receptores/genética , Proteínas Tirosina Fosfatasas Clase 7 Similares a Receptores/metabolismo
14.
J Clin Res Pediatr Endocrinol ; 16(1): 76-83, 2024 03 11.
Artículo en Inglés | MEDLINE | ID: mdl-37847107

RESUMEN

Objective: Noonan syndrome (NS) is characterized by dysmorphic facial features, short stature, congenital heart defects, and varying levels of developmental delays. It is a genetic, multisystem disorder with autosomal dominant inheritance and is the most common of the RASopathies. In approximately 50% of patients, NS is caused by variants in the Protein Tyrosine Phosphatase Non-Receptor Type 11 (PTPN11) gene. The aim of this study was to evaluate two patients with a previously reported PTPN11 homozygous variant for the first time and seven other kindred members carrying the same heterozygous variant in terms of clinical, biochemical, genetic, and response to treatment. Methods: Nine patients diagnosed with NS due to the same variants in the PTPN11 gene were included in the study. Results: The median (range) age at diagnosis was 11.5 (6.8-13.9) years and the mean follow-up duration was 4.7 (1-7.6) years. In eight patients (88.9%), short stature was present. The height standard deviation score of the patients on admission was -3.24±1.15. In six of the patients, growth hormone treatment was initiated. Cardiovascular or bleeding disorders were not detected in any of the patients. Three (33.3%) had hearing loss, two (22.2%) had ocular findings and one (11.1%) had a horseshoe kidney. The mean psychomotor development performance score was 84.03±17.09 and the verbal score was 82.88±9.42. Genetic analysis revealed a variant in the PTPN11 gene [c.772G>A; (p.Glu258Lys)] that had been previously described and was detected in all patients. Two patients were homozygous for this variant and short stature was more severe in these two. Conclusion: A previously described in PTPN11 affected nine members of the same kindred, two with homozygous inheritance and the remainder being heterozygous. To the best of our knowledge, these are the first homozygous PTPN11 case reports published, coming from two related consanguineous families.


Asunto(s)
Enanismo , Síndrome de Noonan , Humanos , Síndrome de Noonan/diagnóstico , Síndrome de Noonan/genética , Proteína Tirosina Fosfatasa no Receptora Tipo 11/genética , Heterocigoto , Fenotipo
16.
J Neurol ; 271(3): 1331-1341, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37923938

RESUMEN

The RASopathies are a group of genetic rare diseases caused by mutations affecting genes involved in the RAS/MAPK (RAS-mitogen activated protein kinase) pathway. Among them, PTPN11 pathogenic variants are responsible for approximately 50% of Noonan syndrome (NS) cases and, albeit to a lesser extent, of Leopard syndrome (LPRD1), which present a few overlapping clinical features, such as facial dysmorphism, developmental delay, cardiac defects, and skeletal deformities. Motor impairment and decreased muscle strength have been recently reported. The etiology of the muscle involvement in these disorders is still not clear but probably multifactorial, considering the role of the RAS/MAPK pathway in skeletal muscle development and Acetylcholine Receptors (AChR) clustering at the neuromuscular junction (NMJ). We report, herein, four unrelated children carrying three different heterozygous mutations in the PTPN11 gene. Intriguingly, their phenotypic features first led to a clinical suspicion of congenital myasthenic syndrome (CMS), due to exercise-induced fatigability with a variable degree of muscle weakness, and serum proteomic profiling compatible with a NMJ defect. Moreover, muscle fatigue improved after treatment with CMS-specific medication. Although the link between PTPN11 gene and neuromuscular transmission is unconfirmed, an increasing number of patients with RASopathies are affected by muscle weakness and fatigability. Hence, NS or LPDR1 should be considered in children with suspected CMS but negative genetic workup for known CMS genes or additional symptoms indicative of NS, such as facial dysmorphism or intellectual disability.


Asunto(s)
Síndromes Miasténicos Congénitos , Síndrome de Noonan , Niño , Humanos , Síndrome de Noonan/genética , Síndrome de Noonan/diagnóstico , Síndrome de Noonan/patología , Síndromes Miasténicos Congénitos/genética , Proteómica , Mutación/genética , Fenotipo , Debilidad Muscular , Proteína Tirosina Fosfatasa no Receptora Tipo 11/genética
17.
J Appl Genet ; 65(2): 303-308, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-37987971

RESUMEN

Noonan syndrome (NS; OMIM 163950) is an autosomal dominant RASopathy with variable clinical expression and genetic heterogeneity. Clinical manifestations include characteristic facial features, short stature, and cardiac anomalies. Variants in protein-tyrosine phosphatase, non-receptor-type 11 (PTPN11), encoding SHP-2, account for about half of NS patients, SOS1 in approximately 13%, RAF1 in 10%, and RIT1 each in 9%. Other genes have been reported to cause NS in less than 5% of cases including SHOC2, RASA2, LZTR1, SPRED2, SOS2, CBL, KRAS, NRAS, MRAS, PRAS, BRAF, PPP1CB, A2ML1, MAP2K1, and CDC42. Several additional genes associated with a Noonan syndrome-like phenotype have been identified. Clinical presentation and variants in patients with Noonan syndrome are this study's objectives. We performed Sanger sequencing of PTPN11 hotspot (exons 3, 8, and 13). We report molecular analysis of 61 patients with NS phenotype belonging to 58 families. We screened for hotspot variants (exons 3, 8, and 13) in PTPN11 gene by Sanger sequencing. Twenty-seven patients were carrying heterozygous pathogenic variants of PTPN11 gene with a similar frequency (41.4%) compared to the literature. Our findings expand the variant spectrum of Moroccan patients with NS phenotype in whom the analysis of hotspot variants showed a high frequency of exons 3 and 8. This screening test allowed us to establish a molecular diagnosis in almost half of the patients with a good benefit-cost ratio, with appropriate management and genetic counseling.


Asunto(s)
Síndrome de Noonan , Proteína Tirosina Fosfatasa no Receptora Tipo 11 , alfa-Macroglobulinas , Humanos , Exones , Péptidos y Proteínas de Señalización Intracelular/genética , Mutación , Síndrome de Noonan/genética , Síndrome de Noonan/diagnóstico , Síndrome de Noonan/patología , Fenotipo , Proteína Tirosina Fosfatasa no Receptora Tipo 11/genética , Proteínas Activadoras de ras GTPasa/genética , Proteínas Represoras/genética , Factores de Transcripción/genética
18.
J Pediatr Hematol Oncol ; 46(2): e176-e179, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38132703

RESUMEN

Noonan syndrome-related myeloproliferative disorder (NS/MPD) and juvenile myelomonocytic leukemia (JMML) are rare MPDs that occur in young children. We herein report a case of NS/MPD with neonatal onset. The patient had a characteristic appearance and high monocyte count in the peripheral blood and bone marrow. Genetic testing showed the E139D mutation in PTPN11 ; however, the patient did not meet all the diagnostic criteria for JMML, and we thus diagnosed him with NS/MPD. Eight other cases of NS/MPD with neonatal onset are also summarized. The initial presentation varied, and the prognosis was considered poor compared with previous reports of NS/MPD.


Asunto(s)
Leucemia Mielomonocítica Juvenil , Trastornos Mieloproliferativos , Síndrome de Noonan , Humanos , Recién Nacido , Masculino , Leucemia Mielomonocítica Juvenil/complicaciones , Leucemia Mielomonocítica Juvenil/diagnóstico , Leucemia Mielomonocítica Juvenil/genética , Mutación , Trastornos Mieloproliferativos/complicaciones , Trastornos Mieloproliferativos/genética , Síndrome de Noonan/complicaciones , Síndrome de Noonan/genética , Proteína Tirosina Fosfatasa no Receptora Tipo 11/genética
19.
Stem Cell Res ; 74: 103293, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-38160629

RESUMEN

We have established Noonan syndrome (NS)-derived induced pluripotent stem cell (iPSC) lines derived from peripheral blood mononuclear cells (PBMCs) of a family cohort carrying the heterozygous PTPN11 c.188 A > G (p.Y63C) mutation. The new iPSC lines were validated by confirming the normal karyotype and targeted mutation, the pluripotent gene expression, and the differentiation capacity into three germ layers.


Asunto(s)
Células Madre Pluripotentes Inducidas , Síndrome de Noonan , Humanos , Células Madre Pluripotentes Inducidas/metabolismo , Síndrome de Noonan/genética , Síndrome de Noonan/metabolismo , Leucocitos Mononucleares , Mutación/genética , Heterocigoto , Proteína Tirosina Fosfatasa no Receptora Tipo 11/genética
20.
Cancer Lett ; 582: 216517, 2024 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-38101609

RESUMEN

Src homology 2 domain-containing phosphatase (SHP2) is a non-receptor protein phosphatase that transduces signals from upstream receptor tyrosine kinases (RTKs)/non-RTKs to Ras/MAPK pathway. Accumulating studies indicated that SHP2 is a critical mediator of resistance to current targeted therapies in multiple cancers. Here, we reported a novel SHP2 allosteric inhibitor JC-010a, which was highly selective to SHP2 and bound at the "tunnel" allosteric site of SHP2. The effect of JC-010a on combating RTK/non-RTK or MAPK inhibitors-induced acquired resistance was explored. Our study demonstrated that JC-010a monotherapy significantly inhibited the proliferation of cancer cells with different oncogenic drivers via inhibiting signaling through SHP2. Importantly, JC-010a abolished acquired resistance induced by targeted therapies: in KRAS-mutant cancers, JC-010a abrogated selumetinib-induced adaptive resistance mediated by RTK/SHP2; in BCR-ABL-driven leukemia cells, we demonstrated JC-010a inhibited BCR-ABL T315I mutation-mediated imatinib resistance and proposed a novel mechanism of JC-010a involving the disrupted co-interaction of SHP2, BCR-ABL, and Hsp90; in non-small cell lung cancer (NSCLC) cells, JC-010a inhibited both EGFR T790M/C797S mutation and alternate RTK-driven resistance to gefitinib or osimertinib; importantly, we first proposed a novel potential therapeutic strategy for RET-rearranged cancer, we confirmed that JC-010a monotherapy inhibited cell resistance to BLU-667, and JC-010a/BLU-667 combination prolonged anticancer response both in vivo and in vitro cancer models by inhibiting the alternate MET activation-induced RAS/MAPK reactivation, thereby promoting cancer cell apoptosis. These findings suggested that JC-010a was a novel selective SHP2 allosteric inhibitor, and combing JC-010a with current targeted therapy agents provided a promising therapeutic approach for clinical resistant cancers.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Receptores ErbB/genética , Carcinoma de Pulmón de Células no Pequeñas/genética , Inhibidores de Proteínas Quinasas/farmacología , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Mutación , Oncogenes , Resistencia a Medicamentos , Proteína Tirosina Fosfatasa no Receptora Tipo 11/genética , Proteína Tirosina Fosfatasa no Receptora Tipo 11/metabolismo , Línea Celular Tumoral
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA