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1.
Mod Pathol ; 36(11): 100294, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37532182

RESUMO

Gliomas harboring oncogenic ROS1 alterations are uncommon and primarily described in infants. Our goal was to characterize the clinicopathological features and molecular signatures of the full spectrum of ROS1 fusion-positive gliomas across all age groups. Through a retrospective multi-institutional collaboration, we report a collection of unpublished ROS1 fusion gliomas along with the characterization and meta-analysis of new and published cases. A cohort of 32 new and 58 published cases was divided into the following 3 age groups: 19 infants, 40 pediatric patients, and 31 adults with gliomas. Tumors in infants and adults showed uniformly high-grade morphology; however, tumors in pediatric patients exhibited diverse histologic features. The GOPC::ROS1 fusion was prevalent (61/79, 77%) across all age groups, and 10 other partner genes were identified. Adult tumors showed recurrent genomic alterations characteristic of IDH wild-type glioblastoma, including the +7/-10/CDKN2A deletion; amplification of CDK4, MDM2, and PDGFRA genes; and mutations involving TERTp, TP53, PIK3R1, PIK3CA, PTEN, and NF1 genes. Infant tumors showed few genomic alterations, whereas pediatric tumors showed moderate genomic complexity. The outcomes were significantly poorer in adult patients. Although not statistically significant, tumors in infant and pediatric patients with high-grade histology and in hemispheric locations appeared more aggressive than tumors with lower grade histology or those in nonhemispheric locations. In conclusion, this study is the largest to date to characterize the clinicopathological and molecular signatures of ROS1 fusion-positive gliomas from infant, pediatric, and adult patients. We conclude that ROS1 likely acts as a driver in infant and pediatric gliomas and as a driver or codriver in adult gliomas. Integrated comprehensive clinical testing might be helpful in identifying such patients for possible targeted therapy.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Glioma , Humanos , Criança , Adulto , Lactente , Adulto Jovem , Proteínas Tirosina Quinases/genética , Estudos Retrospectivos , Proteínas Proto-Oncogênicas/genética , Glioma/genética , Glioma/patologia , Glioblastoma/genética , Mutação , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia
2.
BMC Palliat Care ; 21(1): 88, 2022 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-35614433

RESUMO

BACKGROUND: The care of palliative patients takes place as non-specialized and specialized care, in outpatient and inpatient settings. However, palliative care is largely provided as General Outpatient Palliative Care (GOPC). This study aimed to investigate whether the survival curves of GOPC patients differed from those of the more intensive palliative care modalities and whether GOPC palliative care was appropriate in terms of timing. METHODS: The study is based on claims data from a large statutory health insurance. The analysis included 4177 patients who received palliative care starting in 2015 and who were fully insured 1 year before and 1 year after palliative care or until death. The probability of survival was observed for 12 months. Patients were classified into group A, which consisted of patients who received palliative care only with GOPC, and group B including patients who received inpatient or specialized outpatient palliative care. Group A was further divided into two subgroups. Patients who received GOPC on only 1 day were assigned to subgroup A1, and patients who received GOPC on two or more days were assigned to subgroup A2. The survival analysis was carried out using Kaplan-Meier curves. The median survival times were compared with the log-rank test. RESULTS: The survival curves differed between groups A and B, except in the first quartile of the survival distribution. The median survival was significantly longer in group A (137 days, n = 2763) than in group B (47 days, n = 1424, p < 0.0001) and shorter in group A1 (35 days, n = 986) than in group A2 (217 days, n = 1767, p < 0.0001). The survival rate during the 12-month follow-up was higher in group A (42%) than in group B (11%) and lower in group A1 (38%) than in group A2 (44%). CONCLUSIONS: The results of the analysis revealed that patients who received the first palliative care shortly before death suspected insufficient care, especially patients who received GOPC for only 1 day and no further palliative care until death or 12-month follow-up. Palliative care should start as early as necessary and be continuous until the end of life.


Assuntos
Enfermagem de Cuidados Paliativos na Terminalidade da Vida , Cuidados Paliativos , Assistência Ambulatorial/métodos , Humanos , Seguro Saúde , Pacientes Ambulatoriais , Cuidados Paliativos/métodos
3.
West Afr J Med ; 38(7): 705-708, 2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34331530

RESUMO

COVID 19 viral infection is a rapidly spreading droplets infection that has a global impact. Kaduna is one of the states in Nigeria with a high number of COVID-19 infected individuals. Some staff of Barau Dikko Teaching Hospital, Kaduna (BDTH) were infected with COVID-19 during the initial period of the pandemic. Most of the infected staff were from the General Out-Patient Clinic (GOPC), as it was the only Department with up to 11 staff infected during this initial period of the COVID-19 pandemic. This had led to the temporary closure of the Department. The aim of this paper is to characterize the GOPC Staff that tested positive to COVID-19 following previous contact with COVID-19 patients that were seen at the GOPC during the first wave of the pandemic. This is with the view to consider GOPC staff as high risk and frontline health workers for COVID 19. It was a retrospective study, and data were collected from the record of all the staff of the GOPC who were traced to have had contact with the COVID-19 positive patients and were also tested positive. Eleven (34%) out of the 32 staff were infected with COVID-19 at the GOPC. Only 1 staff was above 50 years. Most of them had mild symptoms and had side effects from the antiviral drugs. Staff of the GOPC are at risk of COVID-19 infection and should be considered frontline workers for COVID-19.


L'infection virale COVID 19 est une infection par gouttelettes à propagation rapide qui a un impact mondial. Kaduna est l'un des États du Nigéria comptant un nombre élevé de personnes infectées par le COVID-19. Certains membres du personnel de l'hôpital universitaire Barau Dikko de Kaduna (BDTH) ont été infectés par le COVID-19 au cours de la période initiale de la pandémie. La plupart du personnel infecté provenait de la Clinique générale de consultation externe (GOPC), car c'était le seul département avec jusqu'à 11 membres du personnel infectés au cours de cette période initiale de la pandémie de COVID-19. Cela a conduit à la fermeture temporaire du département. Le but de cet article est de caractériser le personnel du GOPC qui a été testé positif au COVID-19 à la suite de contacts antérieurs avec des patients COVID-19 qui ont été vus au GOPC pendant la première vague de la pandémie. Ceci dans le but de considérer le personnel du GOPC comme des agents de santé à haut risque et de première ligne pour COVID 19. Il s'agissait d'une étude rétrospective, et les données ont été collectées à partir du dossier de tout le personnel du GOPC qui a été identifié comme ayant été en contact avec le COVID -19 patients positifs et ont également été testés positifs. Onze (34%) des 32 employés ont été infectés par COVID-19 au GOPC. Seul 1 membre du personnel avait plus de 50 ans. La plupart d'entre eux présentaient des symptômes bénins et des effets secondaires des médicaments antiviraux. Le personnel du GOPC est à risque d'infection au COVID-19 et doit être considéré comme un travailleur de première ligne pour le COVID-19 Mots-clés: Covid 19, Personnels, GOPC.


Assuntos
COVID-19 , Pandemias , Comunicação , Hospitais de Ensino , Humanos , Nigéria , Pacientes Ambulatoriais , Estudos Retrospectivos , SARS-CoV-2 , Universidades
4.
Ceska Gynekol ; 81(6): 437-443, 2016.
Artigo em Tcheco | MEDLINE | ID: mdl-27918162

RESUMO

OBJECTIVE: To present the results of molecular genetics analysis in men with reproductive disorders focusing on the DNA segments and genes which affect spermatogenesis. DESIGN: Original article. SETTING: Institute of Biology and Medical Genetics of the First Faculty of Medicine and General Teaching Hospital, Prague. METHODS: One hundred and twenty-three patients identified with a fertility disorder were screened for mutations of the CFTR gene. In all patients were performed cytogenic analysis and assessment of Y-chromosome microdeletions. In 107 patients where the fertility was not detected by routine examination we performed an analysis for X-chromosome microdeletions (CNV64, CNV67, CNV69) and in certain genes necessary for normal spermatogenesis (AGFG1, CAPZA3, CNTROB, HOOK1, GOPC, SPATA16). RESULTS: Our results did not reveal any negative efffects of X-chromosome microdeletion on spermatogenesis. Analysis of six genes showed in two patients in gene SPATA16 a homozygotic haplotype [1526C>T + 1577T>C] which can be most probably responsible for the fertility in two examined patients. CONCLUSION: According to our results we do not recommend introduction of X-chromosome microdeletions assays in areas CNV64 , CNV67 and CNV69 into routine diagnostic. Regarding the selected genes affecting spermatogenesis, our results showed that homozygotic haplotype [ 1526C>T + 1577T>C] in SPATA16 gene is very likely responsible for infertility in two of our patients. The above mentioned haplotype deserves attention in the investigation of male infertility.


Assuntos
Infertilidade Masculina/etiologia , Espermatogênese/genética , Haplótipos , Proteínas de Homeodomínio/genética , Humanos , Masculino , Proteínas de Transporte Vesicular
5.
Microsc Res Tech ; 85(4): 1454-1464, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34870349

RESUMO

Globozoospermia is a type of teratozoospermia characterized by round morphology of the sperm head. Gopc-/- infertile globozoospermic murine model has failures during spermiogenesis, such as the incorrect biogenesis of the acrosome, disorganized acroplaxome and manchette, round nuclei and spiral flagella. In this study, Western blot, RT-PCR, immunohistochemistry and immunogold were done for the localization of the acrosome protein Zona Pellucida sperm-binding protein 3 receptor (ZP3R), also called sp56, in wild type and Gopc-/- mice testis. The ZP3R protein was located in the acrosome and pseudo-acrosome vesicles of wild type and Gopc-/- mice, respectively. Also, it is distributed through the cytoplasm of the haploid spermatids only. The incorrect spermiogenesis of Gopc-/- mice causes a deregulation in the expression of ZP3R in the globozoospermic spermatids. Our results suggest that although the lack of GOPC causes a failure during the transport of the pre-acrosomal vesicles, the acrosome protein ZP3R is localized in the acrosome and is distributed through the cytoplasm only during spermiogenesis. Furthermore, the failure in spermiogenesis does not impair the synthesis of ZP3R and its localization in the pre-acrosomal vesicles.


Assuntos
Receptores de Superfície Celular/metabolismo , Espermatogênese , Zona Pelúcida , Acrossomo/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Proteínas da Matriz do Complexo de Golgi/metabolismo , Masculino , Camundongos , Proteínas de Plasma Seminal , Espermátides , Espermatozoides/fisiologia
6.
Virchows Arch ; 479(3): 559-564, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33733342

RESUMO

Spitz tumors are genetically associated with activating HRAS point mutations or fusions of either ALK, ROS1, NTRK1, NTRK3, RET, MET, MERTK, LCK, BRAF, MAP3K8, or MAP3K3. All these driver gene alterations are mutually exclusive. We report two cases of agminated Spitz naevi with a GOPC-ROS1 fusion. Both cases occurred on the lower limb of young adults. Since adolescence, pigmented or pink-colored papules have been periodically arising in a limited area of skin. In one case, an ill-defined hyperpigmented macule known since childhood was present in the background. Morphologically, at least five lesions were analyzed from each patient. In one case, all were predominantly junctional pigmented Spitz naevi, and in the other case, all were compound unpigmented Spitz naevi. No atypical features were present. RNA-sequencing revealed a GOPC-ROS1 gene translocation in both cases. Split signals of ROS1 gene in fluorescence in situ hybridization were observed not only in the nests of spitzoid melanocytes but also in the bland basal melanocytes surrounding the proliferations. These findings suggest the presence of a GOPC-ROS1 mosaicism in melanocytes with further emergence of agminated Spitz naevi potentially triggered by other genetic alterations. This expands the spectrum of genetic anomalies described in agminated Spitz naevi and our understanding of the mechanisms involved in their emergence.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Biomarcadores Tumorais/genética , Fusão Gênica , Proteínas da Matriz do Complexo de Golgi/genética , Mosaicismo , Nevo de Células Epitelioides e Fusiformes/genética , Proteínas Tirosina Quinases/genética , Proteínas Proto-Oncogênicas/genética , Neoplasias Cutâneas/genética , Feminino , Predisposição Genética para Doença , Humanos , Hibridização in Situ Fluorescente , Masculino , Melanócitos/patologia , Nevo de Células Epitelioides e Fusiformes/patologia , Fenótipo , Análise de Sequência de RNA , Neoplasias Cutâneas/patologia , Sequenciamento do Exoma , Adulto Jovem
7.
Niger Med J ; 62(6): 325-333, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-38736516

RESUMO

Background: Waiting time is an important indicator of the quality of healthcare services in public and private health facilities. This study compared the waiting time at the general outpatient clinics (GOPC) in a private and public hospital in Rivers State. Methods: A comparative cross-sectional survey using a multi-stage sampling technique was used to select a total of 299 ambulatory adult patients attending the GOPC in a public and a private hospital. Time spent at service stations was obtained using a record sheet. SPSS version 23 was used to analyze data and p-values ≤0.05 were considered significant. Results: Ambulatory patients on average spend 122.6 minutes for GOPC encounters in the public hospital and 44.9 minutes in the private hospital. This difference of 77.8 (95%CI: 66.6, 89.0) minutes was statistically significant (p = 0.001). Conclusion: The duration of time spent to access GOPC services underscores the need for system redesign to reduce the time spent and improve the satisfaction of patients attending the GOPC.

8.
Andrology ; 7(3): 319-328, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30786176

RESUMO

BACKGROUND: Golgi-associated PDZ and coiled-coil motif-containing protein (GOPC) is a Golgi protein that plays a role in vesicular transport and intracellular protein trafficking and degradation. Mice deficient in GOPC protein have globozoospermia and are infertile. The germ cell nuclear factor (GCNF) is a member of the nuclear receptor superfamily which is expressed in male germ cells, from spermatocytes and spermatids, both in the nucleus and the acrosomal region. It is not known if its expression could be altered in Gopc-/- mice with defective acrosomes. OBJECTIVES: The aim of the present work was to analyze the distribution of GCNF protein in spermatids of Gopc-/- knockout mice. MATERIALS AND METHODS: We have analyzed the expression and distribution during spermatogenesis of GCNF and its deregulation in Gopc-/- mutant mice by RT-qPCR, Western blot, immunohistochemistry and immunogold. RESULTS: Germ cell nuclear factor was localized in the nucleus of all the cell types in the seminiferous tubules. Despite being a nuclear protein, it was also located in the acrosome and in the manchette of elongating spermatids. We have found that in the absence of GOPC, the expression of GCNF was increased in the nucleus of spermatocytes, mainly in leptotene, and in the nucleus and the manchette during the spermatid elongation. DISCUSSION AND CONCLUSION: Gopc-/- mice have defective acrosome and manchette. The manchette is involved in the transport of proteins through the cytoplasm and the nucleus. Considering that the GCNF protein is normally transported to the acrosome and the nucleus, it can be thought that transport deficiencies in Gopc-/- mice are responsible for the increased expression of this protein.


Assuntos
Membro 1 do Grupo A da Subfamília 6 de Receptores Nucleares/metabolismo , Espermátides/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Western Blotting , Núcleo Celular/metabolismo , Proteínas da Matriz do Complexo de Golgi/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Espermátides/ultraestrutura , Espermatogênese , Testículo/metabolismo
9.
Oncotarget ; 10(2): 245-251, 2019 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-30719217

RESUMO

Hepatic angiosarcoma (HAS) is a rare and highly lethal malignancy with few effective systemic treatments. Relatively little is known about the genetic abnormalities that drive this disease. As a result, there has been minimal progress towards applying targeted therapies to the treatment of HAS. We describe the first reported case of a patient with HAS that harbored a fusion of ROS1 with GOPC/FIG. Similar to other rearrangements involving ROS1, the resulting fusion protein is believed to act as a major driver of carcinogenesis and may be subject to inhibition by drugs that target ROS1 such as crizotinib. We then queried the MSK-IMPACT clinical sequencing cohort and cBioportal datasets, demonstrating the previously unknown prevalence of ROS1-GOPC fusions in soft tissue sarcomas and hepatobiliary cancers. Amplification of these genes was also found to correlate with reduced overall survival. This is followed by a review of the role played by ROS1 rearrangements in cancer, as well as the evidence supporting the use of targeted therapies against the resulting fusion protein. We suggest that testing for ROS1 fusion and, if positive, treatment with a targeted therapy could be considered at the time of diagnosis for patients with angiosarcoma. This report also highlights the need for further investigation into the molecular pathophysiology of this deadly disease.

10.
J Neuropathol Exp Neurol ; 78(12): 1089-1099, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31626289

RESUMO

ROS1 is a transmembrane receptor tyrosine kinase proto-oncogene that has been shown to have rearrangements with several genes in glioblastoma and other neoplasms, including intrachromosomal fusion with GOPC due to microdeletions at 6q22.1. ROS1 fusion events are important findings in these tumors, as they are potentially targetable alterations with newer tyrosine kinase inhibitors; however, whether these tumors represent a distinct entity remains unknown. In this report, we identify 3 cases of unusual pediatric glioma with GOPC-ROS1 fusion. We reviewed the clinical history, radiologic and histologic features, performed methylation analysis, whole genome copy number profiling, and next generation sequencing analysis for the detection of oncogenic mutation and fusion events to fully characterize the genetic and epigenetic alterations present in these tumors. Two of 3 tumors showed pilocytic features with focal expression of synaptophysin staining and variable high-grade histologic features; the third tumor aligned best with glioblastoma and showed no evidence of neuronal differentiation. Copy number profiling revealed chromosome 6q22 microdeletions corresponding to the GOPC-ROS1 fusion in all 3 cases and methylation profiling showed that the tumors did not cluster together as a single entity or within known methylation classes by t-Distributed Stochastic Neighbor Embedding.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Neoplasias Encefálicas/genética , Deleção Cromossômica , Cromossomos Humanos Par 6/genética , Glioma/genética , Proteínas da Matriz do Complexo de Golgi/genética , Proteínas de Fusão Oncogênica/genética , Proteínas Tirosina Quinases/genética , Proteínas Proto-Oncogênicas/genética , Encéfalo/patologia , Neoplasias Encefálicas/patologia , Carcinogênese , Criança , Pré-Escolar , Metilação de DNA , Epigênese Genética , Feminino , Glioma/patologia , Humanos , Masculino , Proto-Oncogene Mas
11.
J Neurosurg Pediatr ; 20(1): 51-55, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28387643

RESUMO

Pediatric high-grade glioma is a rare tumor characterized by high mortality. The authors report the first case of a high-grade glioma associated with a GOPC(FIG)-ROS1 fusion in a pediatric patient. The patient underwent gross-total resection at the age of 4 years, followed by adjuvant high-dose chemotherapy and autologous hematopoietic stem cell rescue. At 30 months after transplantation, she remains disease free.


Assuntos
Neoplasias Encefálicas/genética , Neoplasias Encefálicas/cirurgia , Proteínas de Transporte/genética , Glioma/genética , Glioma/cirurgia , Proteínas de Membrana/genética , Proteínas Tirosina Quinases/genética , Proteínas Proto-Oncogênicas/genética , Proteínas Adaptadoras de Transdução de Sinal , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Encéfalo/cirurgia , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/patologia , Pré-Escolar , Feminino , Glioma/diagnóstico por imagem , Glioma/patologia , Proteínas da Matriz do Complexo de Golgi , Humanos , Proteínas de Membrana Transportadoras , Gradação de Tumores , Deleção de Sequência , Sobreviventes
12.
Autophagy ; 11(3): 503-15, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25714412

RESUMO

Autophagy is an essential component of host innate and adaptive immunity. Viruses have developed diverse strategies for evading or utilizing autophagy for survival. The response of the autophagy pathways to virus invasion is poorly documented. Here, we report on the induction of autophagy initiated by the pathogen receptor HSP90AA1 (heat shock protein 90 kDa α [cytosolic], class A member 1) via the AKT-MTOR (mechanistic target of rapamycin)-dependent pathway. Transmission electron microscopy and confocal microscopy revealed that intracellular autolysosomes packaged avibirnavirus particles. Autophagy detection showed that early avibirnavirus infection not only increased the amount of light chain 3 (LC3)-II, but also upregulated AKT-MTOR dephosphorylation. HSP90AA1-AKT-MTOR knockdown by RNA interference resulted in inhibition of autophagy during avibirnavirus infection. Virus titer assays further verified that autophagy inhibition, but not induction, enhanced avibirnavirus replication. Subsequently, we found that HSP90AA1 binding to the viral protein VP2 resulted in induction of autophagy and AKT-MTOR pathway inactivation. Collectively, our findings suggest that the cell surface protein HSP90AA1, an avibirnavirus-binding receptor, induces autophagy through the HSP90AA1-AKT-MTOR pathway in early infection. We reveal that upon viral recognition, a direct connection between HSP90AA1 and the AKT-MTOR pathway trigger autophagy, a critical step for controlling infection.


Assuntos
Autofagia , Avibirnavirus/metabolismo , Proteínas do Capsídeo/metabolismo , Proteínas de Choque Térmico HSP90/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Animais , Membrana Celular/metabolismo , Galinhas , Citosol/metabolismo , Células HEK293 , Humanos , Lisossomos/metabolismo , Microscopia Confocal , Microscopia Eletrônica de Transmissão , Proteínas Associadas aos Microtúbulos/metabolismo , Fagossomos/metabolismo , Fosforilação , Ligação Proteica , Interferência de RNA , RNA Interferente Pequeno/metabolismo
13.
Front Physiol ; 4: 201, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23966943

RESUMO

Although crucial for their correct function, the mechanisms controlling surface expression of ion channels are poorly understood. In the case of the voltage-gated potassium channel KV10.1, this is determinant not only for its physiological function in brain, but also for its pathophysiology in tumors and possible use as a therapeutic target. The Golgi resident protein PIST binds several membrane proteins, thereby modulating their expression. Here we describe a PDZ domain-mediated interaction of KV10.1 and PIST, which enhances surface levels of KV10.1. The functional, but not the physical interaction of both proteins is dependent on the coiled-coil and PDZ domains of PIST; insertion of eight amino acids in the coiled-coil domain to render the neural form of PIST (nPIST) and the corresponding short isoform in an as-of-yet unknown form abolishes the effect. In addition, two new isoforms of PIST (sPIST and nsPIST) lacking nearly the complete PDZ domain were cloned and shown to be ubiquitously expressed. PIST and KV10.1 co-precipitate from native and expression systems. nPIST also showed interaction, but did not alter the functional expression of the channel. We could not document physical interaction between KV10.1 and sPIST, but it reduced KV10.1 functional expression in a dominant-negative manner. nsPIST showed weak physical interaction and no functional effect on KV10.1. We propose these isoforms to work as modulators of PIST function via regulating the binding on interaction partners.

14.
Int J Biochem Cell Biol ; 45(12): 2808-20, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24120647

RESUMO

Complement is undeniably quintessential for innate immunity by detecting and eliminating infectious microorganisms. Recent work, however, highlights an equally profound impact of complement on the induction and regulation of a wide range of immune cells. In particular, the complement regulator CD46 emerges as a key sensor of immune activation and a vital modulator of adaptive immunity. In this review, we summarize the current knowledge of CD46-mediated signalling events and their functional consequences on immune-competent cells with a specific focus on those in CD4(+) T cells. We will also discuss the promises and challenges that potential therapeutic modulation of CD46 may hold and pose.


Assuntos
Proteínas do Sistema Complemento/imunologia , Proteína Cofatora de Membrana/imunologia , Humanos , Imunidade Inata , Transdução de Sinais
15.
Prog Neurobiol ; 106-107: 33-54, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23827971

RESUMO

The accumulation of amyloid-ß-containing neuritic plaques and intracellular tau protein tangles are key histopathological hallmarks of Alzheimer's disease (AD). This type of pathology clearly indicates that the mechanisms of neuronal housekeeping and protein quality control are compromised in AD. There is mounting evidence that the autophagosome-lysosomal degradation is impaired, which could disturb the processing of APP and provoke AD pathology. Beclin 1 is a molecular platform assembling an interactome with stimulating and suppressive components which regulate the initiation of the autophagosome formation. Recent studies have indicated that the expression Beclin 1 is reduced in AD brain. Moreover, the deficiency of Beclin 1 in cultured neurons and transgenic mice provokes the deposition of amyloid-ß peptides whereas its overexpression reduces the accumulation of amyloid-ß. There are several potential mechanisms, which could inhibit the function of Beclin 1 interactome and thus impair autophagy and promote AD pathology. The mechanisms include (i) reduction of Beclin 1 expression or its increased proteolytic cleavage by caspases, (ii) sequestration of Beclin 1 to non-functional locations, such as tau tangles, (iii) formation of inhibitory complexes between Beclin 1 and antiapoptotic Bcl-2 proteins or inflammasomes, (iv) interaction of Beclin 1 with inhibitory neurovirulent proteins, e.g. herpex simplex ICP34.5, or (v) inhibition of the Beclin 1/Vps34 complex through the activation of CDK1 and CDK5. We will shortly introduce the function of Beclin 1 interactome in autophagy and phagocytosis, review the recent evidence indicating that Beclin 1 regulates autophagy and APP processing in AD, and finally examine the potential mechanisms through which Beclin 1 dysfunction could be involved in the pathogenesis of AD.


Assuntos
Doença de Alzheimer/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Proteínas Reguladoras de Apoptose/metabolismo , Autofagia/fisiologia , Proteínas de Membrana/metabolismo , Proteoma/metabolismo , Doença de Alzheimer/genética , Animais , Apoptose/fisiologia , Proteínas Reguladoras de Apoptose/genética , Autofagia/genética , Proteína Beclina-1 , Humanos , Proteínas de Membrana/genética
16.
Front Cell Neurosci ; 6: 26, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22737109

RESUMO

Tastant detection in the oral cavity involves selective receptors localized at the apical extremity of a subset of specialized taste bud cells called taste receptor cells (TRCs). The identification of the genes coding for the taste receptors involved in this process have greatly improved our understanding of the molecular mechanisms underlying detection. However, how these receptors signal in TRCs, and whether the components of the signaling cascades interact with each other or are organized in complexes is mostly unexplored. Here we report on the identification of three new binding partners for the mouse G protein gamma 13 subunit (Gγ13), a component of the bitter taste receptors signaling cascade. For two of these Gγ13 associated proteins, namely GOPC and MPDZ, we describe the expression in taste bud cells for the first time. Furthermore, we demonstrate by means of a yeast two-hybrid interaction assay that the C terminal PDZ binding motif of Gγ13 interacts with selected PDZ domains in these proteins. In the case of the PDZ domain-containing protein zona occludens-1 (ZO-1), a major component of the tight junction defining the boundary between the apical and baso-lateral region of TRCs, we identified the first PDZ domain as the site of strong interaction with Gγ13. This association was further confirmed by co-immunoprecipitation experiments in HEK 293 cells. In addition, we present immunohistological data supporting partial co-localization of GOPC, MPDZ, or ZO-1, and Gγ13 in taste buds cells. Finally, we extend this observation to olfactory sensory neurons (OSNs), another type of chemosensory cells known to express both ZO-1 and Gγ13. Taken together our results implicate these new interaction partners in the sub-cellular distribution of Gγ13 in olfactory and gustatory primary sensory cells.

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