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1.
Nature ; 630(8016): 447-456, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38839969

RESUMO

Increasing rates of autoimmune and inflammatory disease present a burgeoning threat to human health1. This is compounded by the limited efficacy of available treatments1 and high failure rates during drug development2, highlighting an urgent need to better understand disease mechanisms. Here we show how functional genomics could address this challenge. By investigating an intergenic haplotype on chr21q22-which has been independently linked to inflammatory bowel disease, ankylosing spondylitis, primary sclerosing cholangitis and Takayasu's arteritis3-6-we identify that the causal gene, ETS2, is a central regulator of human inflammatory macrophages and delineate the shared disease mechanism that amplifies ETS2 expression. Genes regulated by ETS2 were prominently expressed in diseased tissues and more enriched for inflammatory bowel disease GWAS hits than most previously described pathways. Overexpressing ETS2 in resting macrophages reproduced the inflammatory state observed in chr21q22-associated diseases, with upregulation of multiple drug targets, including TNF and IL-23. Using a database of cellular signatures7, we identified drugs that might modulate this pathway and validated the potent anti-inflammatory activity of one class of small molecules in vitro and ex vivo. Together, this illustrates the power of functional genomics, applied directly in primary human cells, to identify immune-mediated disease mechanisms and potential therapeutic opportunities.


Assuntos
Inflamação , Macrófagos , Proteína Proto-Oncogênica c-ets-2 , Feminino , Humanos , Masculino , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Células Cultivadas , Cromossomos Humanos Par 21/genética , Bases de Dados Factuais , Regulação da Expressão Gênica , Estudo de Associação Genômica Ampla , Genômica , Haplótipos/genética , Inflamação/genética , Doenças Inflamatórias Intestinais/genética , Macrófagos/imunologia , Macrófagos/metabolismo , Macrófagos/patologia , Proteína Proto-Oncogênica c-ets-2/genética , Proteína Proto-Oncogênica c-ets-2/metabolismo , Reprodutibilidade dos Testes , Fatores de Necrose Tumoral/metabolismo , Interleucina-23/metabolismo
2.
J Endocrinol Invest ; 46(6): 1169-1176, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36564598

RESUMO

PURPOSE: An average parathyroid adenoma (PA) weighs < 1 g. This study aimed to characterise giant PAs ≥ 10 g (GPAs) to facilitate surgical management of primary hyperparathyroidism (PHPT). METHODS: All patients with a GPA confirmed on histology were recruited from the Monash University Endocrine Surgery Unit database. Clinical and demographic data were collected and compared to a group of non-GPA patients. RESULTS: A total of 14 GPAs were identified between 2007 and 2018 out of 863 patients (1.6%) with a single PA excised for PHPT. The GPA patients were compared to a control group of 849 non-GPA patients in the same period with similar mean age (62 ± 16 vs 63 ± 14, P = 0.66) and gender distribution (64% vs 75% female, P = 0.35). Pre-operative calcium (Ca) and parathyroid hormone (PTH) levels were significantly higher in GPA patients (P < 0.001). A higher percentage of GPA patients (79%) had concordant localisation studies (ultrasound and sestamibi) than control patients (59%), (P = 0.13), but they were significantly less likely to undergo MIP (55% vs 82%, P = 0.02). The median GPA weighed 12.5 g (IQR 10.5-24.3). Median serum Ca normalised by day 1 post-operatively, while PTH remained elevated. Both serum Ca and PTH levels were in the normal range at 3 months. All GPA lesions were benign on histopathology. CONCLUSION: GPAs are rare and display severe clinical and biochemical abnormalities. Despite their large size, concordant pre-operative imaging was not always achieved, and a few patients were suitable for MIP.


Assuntos
Adenoma , Hiperparatireoidismo Primário , Neoplasias das Paratireoides , Humanos , Feminino , Masculino , Neoplasias das Paratireoides/cirurgia , Neoplasias das Paratireoides/patologia , Tecnécio Tc 99m Sestamibi , Paratireoidectomia/métodos , Adenoma/cirurgia , Hormônio Paratireóideo , Hiperparatireoidismo Primário/diagnóstico , Hiperparatireoidismo Primário/cirurgia
3.
Tech Coloproctol ; 24(12): 1271-1276, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32757156

RESUMO

BACKGROUND: Postoperative colorectal anastomotic strictures are quite common. As such, many techniques have been available to address such a problem, one of which is endoscopic dilation. The aim of the present study was to evaluate the long-term outcomes following endoscopic dilation using a multidiameter balloon. METHODS: A retrospective study was conducted on patients with postoperative anastomotic stenosis treated with endoscopic dilation using a multidiameter balloon at our institution, in January 2005-December 2019 were retrospectively reviewed, excluding those with tumor recurrence. Perioperative factors, complications, and recurrence rates were analyzed. RESULTS: There were 40 patients, (22 males and 18 females, mean age 64.6 ± 10.7 years, range 33-84 years). The median follow-up period was 56 months (interquartile range 22.5-99 months). Only 1 complication occurred, micro-perforation due to guided wire injury, which was managed conservatively. Five (12.5%) patients developed restenosis and underwent repeat balloon dilation. None of the five recurrences required more aggressive management, such as redo anastomosis. CONCLUSIONS: Endoscopic multidiameter balloon dilation is a safe and effective method for treating benign colorectal anastomotic strictures.


Assuntos
Neoplasias Colorretais , Complicações Pós-Operatórias , Adulto , Idoso , Idoso de 80 Anos ou mais , Anastomose Cirúrgica/efeitos adversos , Neoplasias Colorretais/cirurgia , Constrição Patológica/etiologia , Constrição Patológica/cirurgia , Dilatação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/terapia , Estudos Retrospectivos , Resultado do Tratamento
5.
Nature ; 574(7776): 122-126, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31554970

RESUMO

B cells are important in the pathogenesis of many, and perhaps all, immune-mediated diseases. Each B cell expresses a single B cell receptor (BCR)1, and the diverse range of BCRs expressed by the total B cell population of an individual is termed the 'BCR repertoire'. Our understanding of the BCR repertoire in the context of immune-mediated diseases is incomplete, and defining this could provide new insights into pathogenesis and therapy. Here, we compared the BCR repertoire in systemic lupus erythematosus, anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis, Crohn's disease, Behçet's disease, eosinophilic granulomatosis with polyangiitis, and immunoglobulin A (IgA) vasculitis by analysing BCR clonality, use of immunoglobulin heavy-chain variable region (IGHV) genes and-in particular-isotype use. An increase in clonality in systemic lupus erythematosus and Crohn's disease that was dominated by the IgA isotype, together with skewed use of the IGHV genes in these and other diseases, suggested a microbial contribution to pathogenesis. Different immunosuppressive treatments had specific and distinct effects on the repertoire; B cells that persisted after treatment with rituximab were predominately isotype-switched and clonally expanded, whereas the inverse was true for B cells that persisted after treatment with mycophenolate mofetil. Our comparative analysis of the BCR repertoire in immune-mediated disease reveals a complex B cell architecture, providing a platform for understanding pathological mechanisms and designing treatment strategies.


Assuntos
Doenças do Sistema Imunitário/imunologia , Isotipos de Imunoglobulinas/análise , Isotipos de Imunoglobulinas/imunologia , Receptores de Antígenos de Linfócitos B/análise , Receptores de Antígenos de Linfócitos B/imunologia , Adulto , Idoso , Células Clonais/citologia , Células Clonais/imunologia , Humanos , Imunoglobulina A/análise , Imunoglobulina A/imunologia , Switching de Imunoglobulina/imunologia , Imunoglobulina G/análise , Imunoglobulina G/imunologia , Pessoa de Meia-Idade , Adulto Jovem
6.
J Comp Pathol ; 169: 25-29, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31159947

RESUMO

A 16-year-old male Russian blue cat was presented with acute onset of paraparesis of the forelimbs that progressed to tetraparesis. Neurological examination revealed non-ambulatory tetraparesis with decreased postural reactions in all four limbs. Magnetic resonance imaging revealed multifocal nerve root swelling on the right at C6/C7 and C7/T1, while ultrasonography demonstrated swelling of the right brachial plexus. To understand the cause of the nerve swelling, the right musculocutaneous nerve arising from the brachial plexus and the pectoralis muscle were biopsied. Histologically, there was evidence of neurolymphomatosis (neurotropic lymphoma) with Wallerian degeneration and denervation atrophy of myofibres. The neoplastic lymphoid cells expressed CD79a, CD20 and CD56. Based on these findings, a diagnosis of B-cell neurolymphomatosis was made. Expression of CD56, synonymous with neural cell adhesion molecule, is rare in B-cell lymphomas and has not been reported in feline B-cell lymphomas or feline neurolymphomatosis. CD56 expression was suspected to have played an important role in neurotropism of the neoplastic cells in this case.


Assuntos
Doenças do Gato/patologia , Linfoma de Células B/veterinária , Neurolinfomatose/veterinária , Animais , Antígeno CD56 , Gatos , Masculino
7.
HLA ; 90(6): 329-334, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29106067

RESUMO

Genetic studies in complex diseases have been highly successful, but have also been largely one-dimensional: predominantly focusing on the genetic contribution to disease susceptibility. While this is undoubtedly important-indeed it is a pre-requisite for understanding the mechanisms underlying disease development-there are many other important aspects of disease biology that have received comparatively little attention. In this review, I will discuss how existing genetic data can be leveraged to provide new insights into other aspects of disease biology, why such insights could change the way we think about complex disease, and how this could provide opportunities for better therapies and/or facilitate personalised medicine. To do this, I will use the example of Crohn's disease-a chronic form of inflammatory bowel disease that has been one of the main success stories in complex disease genetics. Indeed, thanks to genetic studies, we now have a much more detailed understanding of the processes involved in Crohn's disease development, but still know relatively little about what determines the subsequent disease course (prognosis) and why this differs so considerably between individuals. I will discuss how we came to realise that genetic variation plays an important role in determining disease prognosis and how this has changed the way we think about Crohn's disease genetics. This will illustrate how phenotypic data can be used to leverage new insights from genetic data and will provide a broadly applicable framework that could yield new insights into the biology of multiple diseases.


Assuntos
Doença de Crohn/genética , Regulação da Expressão Gênica , Predisposição Genética para Doença , Variação Genética , Genoma Humano , Alelos , Doença de Crohn/diagnóstico , Doença de Crohn/imunologia , Doença de Crohn/patologia , Proteína Forkhead Box O3/genética , Proteína Forkhead Box O3/imunologia , Proteínas de Ligação ao GTP/genética , Proteínas de Ligação ao GTP/imunologia , Loci Gênicos , Estudo de Associação Genômica Ampla , Humanos , Proteína Adaptadora de Sinalização NOD2/genética , Proteína Adaptadora de Sinalização NOD2/imunologia , Prognóstico , Índice de Gravidade de Doença , Proteína Smad3/genética , Proteína Smad3/imunologia , Receptor 10 Toll-Like/genética , Receptor 10 Toll-Like/imunologia
9.
Anaesth Intensive Care ; 45(3): 365-368, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28486895

RESUMO

We evaluated the incidence of perioperative hyperkalaemia in end-stage renal disease (ESRD) patients undergoing parathyroidectomy and investigated possible contributors to this phenomenon. This was a retrospective cohort study looking at patients who had undergone parathyroidectomy for chronic kidney disease-associated mineral bone disease (CKD-MBD) at The Alfred Hospital, Melbourne, since 2001. Baseline demographics including age, gender, aetiology of renal failure and mode of renal replacement therapy as well as anaesthetic technique and duration of surgery were studied as possible contributors. Perioperative potassium values were compared to preoperative baseline. Following stratification into normokalaemic and hyperkalaemic groups, demographic and operative data were compared. Twenty-two patients met the inclusion criteria with a median (interquartile range, IQR) age of 48.5 (42-59) years. There was a male predominance of 68%. The median (IQR) surgical time was 131 (115-164) minutes. Potassium levels rose perioperatively, with a 27.3% incidence of perioperative hyperkalaemia. Median duration of surgery was longer in the hyperkalaemic patients (167 minutes versus 125 minutes). Following the withdrawal of cinacalcet, parathyroidectomy is increasingly required in ESRD patients with CKD-MBD. Potentially life-threatening hyperkalaemia poses a significant risk in the perioperative period. Serial electrolyte monitoring is crucial to safety in this patient group. A multidisciplinary approach to perioperative management is required to ensure optimal timing of renal replacement therapy and appropriate means of serial blood sampling.


Assuntos
Hiperpotassemia/etiologia , Falência Renal Crônica/complicações , Paratireoidectomia/efeitos adversos , Complicações Pós-Operatórias/etiologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
10.
Clin Otolaryngol ; 42(6): 1153-1160, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28130940

RESUMO

OBJECTIVES: Current preoperative diagnosis of thyroid nodules remains imperfect despite recent advances in cytopathology and molecular diagnostics. False positivity in preoperative fine-needle aspiration cytology (FNAC) may lead to overtreatment of patients, including total thyroidectomy, and sometimes to lawsuits for misdiagnosis and malpractice. In this study, we analysed clinical characteristics and pathologic findings in patients with false positivity for papillary thyroid carcinoma (PTC) in FNAC. METHODS: We retrospectively reviewed permanent pathology results from 3788 patients who underwent thyroid surgery. Among them, 48 patients had lesions that were deemed suspicious or positive (Bethesda class V or VI) for PTC in preoperative FNAC. We reviewed clinic-pathologic data, radiologic findings and surgical planning in these patients. RESULTS: The prevalence of pathologic thyroiditis was significantly higher among patients with false-positive FNAC results than in those with confirmed PTC (54.2% vs 9.2%, P<.001). The analysis of the permanent pathology reports showed that 26 patients had chronic lymphocytic thyroiditis and 22 patients had no evidence of thyroiditis. Among the patients without pathologic thyroiditis, 19 patients (86.4%) had nodular hyperplasia and three (13.6%) had follicular adenoma, while among the patients with pathologic thyroiditis, seven (26.9%) had no nodule, 14 (53.8%) had nodular hyperplasia, two (7.7%) had hyalinized nodules, two (7.7%) had follicular adenoma and one (3.8%) had a hyalinizing trabecular tumour. In 42 patients, the extent of surgery (total thyroidectomy or hemithyroidectomy) was to be determined according to the intra-operative frozen section biopsy results. Among them, four (10.5%) had inconclusive frozen section results, and 38 (90.5%) had benign results on frozen section. CONCLUSIONS: Patient counselling about the possibility of false positivity is still important. And the presence of thyroiditis might create confusion in the interpretation of cytopathologic results.


Assuntos
Biópsia por Agulha Fina , Carcinoma Papilar/patologia , Erros de Diagnóstico , Neoplasias da Glândula Tireoide/patologia , Adulto , Idoso , Carcinoma Papilar/cirurgia , Reações Falso-Positivas , Feminino , Secções Congeladas , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Câncer Papilífero da Tireoide , Neoplasias da Glândula Tireoide/cirurgia , Nódulo da Glândula Tireoide/patologia , Tireoidectomia , Tireoidite/patologia
11.
Clin Exp Allergy ; 47(1): 85-96, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27910159

RESUMO

BACKGROUND: Skin colonization or infection with Staphylococcus aureus is known to trigger aggravation of atopic dermatitis (AD). However, the exact mechanisms by which S. aureus can worsen AD are unknown. OBJECTIVE: We investigated whether and how S. aureus-derived membrane vesicles (MVs) contribute to worsening of AD. METHODS: Immunohistochemical and immunoelectron microscopic analyses were performed to detect staphylococcal protein A (SPA) in the epidermis of AD lesions. HaCaT cells were treated with S. aureus MVs and were analysed for the expression of cytokine genes. Immunopathology and cytokine gene profiles were analysed after topical application of S. aureus MVs to AD-like skin lesions in a mouse model. RESULTS: The MV component SPA was detected in the keratinocytes as well as in the intercellular space of the epidermis of AD lesions colonized with S. aureus. Intact MVs from S. aureus delivered their components to keratinocytes and stimulated pro-inflammatory cytokine gene expression in vitro. A knock-down of Toll-like receptor 2 or nucleotide-binding oligomerization domain 2 using small interfering RNAs suppressed interleukin-8 gene expression. Topical application of intact S. aureus MVs to AD-like skin lesions in the mouse model induced massive infiltration of inflammatory cells and the resulting eczematous dermatitis. This inflammatory reaction was associated with a mixed Th1/Th2 immune response and enhanced expression of chemokine genes in AD-like skin lesions. CONCLUSIONS AND CLINICAL RELEVANCE: This study showed the importance of S. aureus MVs as a potent mediator for worsening of AD among many exogenous worsening factors of AD. Thus, S. aureus MVs may be regarded as one of the therapeutic targets for the management of AD aggravation.


Assuntos
Micropartículas Derivadas de Células/imunologia , Dermatite Atópica/etiologia , Dermatite Atópica/patologia , Infecções Estafilocócicas/complicações , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/fisiologia , Animais , Biópsia , Micropartículas Derivadas de Células/metabolismo , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Humanos , Mediadores da Inflamação/metabolismo , Camundongos , Pele/imunologia , Pele/metabolismo , Pele/patologia , Pele/ultraestrutura
12.
Leukemia ; 30(10): 2039-2046, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27271228

RESUMO

Osteoblasts (OBs) are indispensable for the maintenance of hematopoietic stem cells (HSCs) in the bone marrow microenvironment. Here we investigated how Smad4 modulates HSC fate at distinct stages of OB development. For this, we conditionally knocked out Smad4 in cells expressing type I collagen (Col1a1) and osteocalcin (OC), respectively. Col1a1-expressing OBs were widely present in both the trabecular and cortical compartment, whereas OC-expressing OBs were predominantly located in the cortical compartment. HSCs from Col1a1 mutants displayed senescence-associated phenotypes. OC mutants did not exhibit HSC senescence-related phenotypes, but instead showed preferential HSC death. Of note, stromal cell-derived factor 1 expression was lower in Col1a1 mutants than control littermates, suggesting potential impairment of CXCR4-CXCL12-mediated HSC retention. Disruption of the CXCR4-CXCL12 axis by AMD3100 administration led to an increase in the senescence-associated ß-galactosidase activity and low competitive potential. Collectively, our findings indicate that deletion of Smad4 in OBs differentially modulates HSC fate in a stage-dependent manner.


Assuntos
Células-Tronco Hematopoéticas/citologia , Osteoblastos/citologia , Proteína Smad4/fisiologia , Animais , Medula Óssea , Osso Esponjoso/citologia , Diferenciação Celular , Linhagem da Célula , Senescência Celular , Colágeno Tipo I/metabolismo , Cadeia alfa 1 do Colágeno Tipo I , Osso Cortical/citologia , Camundongos , Camundongos Knockout , Osteoblastos/química , Osteocalcina/metabolismo , Proteína Smad4/genética
13.
J Environ Pathol Toxicol Oncol ; 35(1): 11-28, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27279581

RESUMO

Natural marine products show various biological properties such as antiphotoaging, antioxidant, anticancer, and anti-inflammation. This study evaluated the protective effects of the brown alga Carpomitra costata (Stackhouse) Batters (Sporochnaceae) against ultraviolet B (UVB)-provoked damage in human HaCaT keratinocytes. C. costata extract (CCE) effectively reduced superoxide anion, hydroxyl radical, and UVB-stimulated intracellular reactive oxygen species (ROS) levels. CCE also restored the expression and activity of UVB-suppressed antioxidant enzymes. Furthermore, CCE decreased UVB-triggered oxidative damage to cellular components including DNA, protein, and lipid and defended the cells against mitochondrial membrane depolarization-medicated apoptosis. The results of this study indicate that CCE can safeguard human keratinocytes against UVB-induced cellular damage via a potent antioxidant mechanism. CCE may find utility as part of a therapeutic arsenal against the damaging effects of UVB radiation on the skin.


Assuntos
Antioxidantes/metabolismo , Queratinócitos/efeitos dos fármacos , Queratinócitos/efeitos da radiação , Phaeophyceae/química , Extratos Vegetais/farmacologia , Envelhecimento da Pele/efeitos dos fármacos , Raios Ultravioleta , Humanos
14.
Oncogene ; 35(45): 5872-5881, 2016 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-27132510

RESUMO

Colon cancer is the third leading cause of death from cancer worldwide with less than 10% survival rate at the late stage. Although mutations of certain genes have been implicated in familial colon cancer development, the etiology of the majority of colon cancer remains unknown. Herein, we identified TYRO3 as a potential oncogene. Immunohistochemical staining results demonstrated that levels of TYRO3 were markedly elevated in polyps and colon cancer cells and were negatively correlated with prognosis. Overexpression of TYRO3 enhanced cell motility, invasion, anchorage-independent growth and metastatic ability, while knockdown of TYRO3 impaired all these processes. Results from meta-analysis showed that TYRO3 was associated with epithelial-mesenchymal transition (EMT) signatures. Gain-of-function and loss-of-function experiments demonstrated that expression of SNAI1, the master regulator of EMT, was regulated by TYRO3 and played a major role in mediating TYRO3-induced EMT processes. The murine model also demonstrated that Tyro3 and Snai1 were upregulated in the early stage of colon cancer development. To provide a proof-of-concept that TYRO3 is a druggable target in colon cancer therapy, we raised anti-TYRO3 human antibodies and showed that treatment with the human antibody abolished TYRO3-induced EMT process. More importantly, administration of this anti-TYRO3 antibody increased drug sensitivity in primary cultured colon cancer cells and xenografted mouse tumors. These findings demonstrate that TYRO3 is a novel oncogene and a druggable target in colon cancer.


Assuntos
Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Resistencia a Medicamentos Antineoplásicos/genética , Transição Epitelial-Mesenquimal/genética , Receptores Proteína Tirosina Quinases/genética , Animais , Linhagem Celular Tumoral , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Análise por Conglomerados , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/metabolismo , Pólipos do Colo/genética , Pólipos do Colo/metabolismo , Pólipos do Colo/patologia , Modelos Animais de Doenças , Progressão da Doença , Expressão Gênica , Perfilação da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Masculino , Camundongos , Receptores Proteína Tirosina Quinases/metabolismo , Transdução de Sinais , Fatores de Transcrição da Família Snail/genética , Fatores de Transcrição da Família Snail/metabolismo
15.
Cell Death Dis ; 6: e1964, 2015 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-26539911

RESUMO

Novel therapeutic strategies are needed to overcome cancer recurrence, metastasis, and resistance to chemo- and radiotherapy. Cancer stem cells (CSCs) are major contributors to the malignant transformation of cells due to their capacity for self-renewal. Although various CSC markers have been identified in several types of tumors, they are primarily used as cancer-prediction markers and for the isolation of CSC populations. CD133, one of the best-characterized CSC markers in distinct solid tumor types, was shown to be correlated with CSC tumor-initiating capacity; however, the regulation of CD133 expression and its function in cancer are poorly understood. Here, we show that CD133 expression is negatively regulated by direct binding of the p53 tumor suppressor protein to a noncanonical p53-binding sequence in the CD133 promoter. Binding of p53 recruits Histone Deacetylase 1 (HDAC1) to the CD133 promoter and subsequently suppresses CD133 expression by reducing histone H3 acetylation. Furthermore, CD133 depletion suppresses tumor cell proliferation, colony formation, and the expression of core stemness transcription factors including NANOG, octamer-binding transcription factor 4 (OCT4), SOX2, and c-MYC. Critically, the anti-proliferative effects of p53 are antagonized by rescue of CD133 expression in a p53 overexpressing cell line, indicating that the tumor suppressive activity of p53 might be mediated by CD133 suppression. Taken together, our results suggest that p53-mediated transcriptional regulation of CD133 is a key underlying mechanism for controlling the growth and tumor-initiating capacity of CSCs and provide a novel perspective on targeting CSCs for cancer therapy.


Assuntos
Antígenos CD/genética , Glicoproteínas/genética , Células-Tronco Neoplásicas/fisiologia , Peptídeos/genética , Proteína Supressora de Tumor p53/genética , Antígeno AC133 , Antígenos CD/metabolismo , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Glicoproteínas/metabolismo , Células HeLa , Humanos , Células Jurkat , Células MCF-7 , Células-Tronco Neoplásicas/citologia , Células-Tronco Neoplásicas/metabolismo , Peptídeos/metabolismo , Proteína Supressora de Tumor p53/metabolismo
16.
Neuroscience ; 300: 508-17, 2015 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-26037803

RESUMO

Astrocytes are major supportive cells in brains with important functions including providing nutrients and regulating neuronal activities. In this study, we demonstrated that astrocytes regulate amyloid precursor protein (APP) processing in neuronal cells through secretion of group IIA secretory phospholipase A2 (sPLA2-IIA). When astrocytic cells (DITNC) were mildly stimulated with the pro-inflammatory cytokines, such as TNF α and IL-1ß, sPLA2-IIA was secreted into the medium. When conditioned medium containing sPLA2-IIA was applied to human neuroblastoma (SH-SY5Y) cells, there was an increase in both cell membrane fluidity and secretion of α-secretase-cleaved soluble amyloid precursor protein (sAPPα). These changes were abrogated by KH064, a selective inhibitor of sPLA2-IIA. In addition, exposing SH-SY5Y cells to recombinant human sPLA2-IIA also increased membrane fluidity, accumulation of APP at the cell surface, and secretion of sAPPα, but without altering total expressions of APP, α-secretases and ß-site APP cleaving enzyme (BACE1). Taken together, our results provide novel information regarding a functional role of sPLA2-IIA in astrocytes for regulating APP processing in neuronal cells.


Assuntos
Secretases da Proteína Precursora do Amiloide/metabolismo , Astrócitos/metabolismo , Fosfolipases A2 do Grupo II/metabolismo , Neurônios/enzimologia , Neurônios/metabolismo , Peptídeos beta-Amiloides/metabolismo , Astrócitos/efeitos dos fármacos , Western Blotting , Linhagem Celular Tumoral , Membrana Celular/efeitos dos fármacos , Membrana Celular/enzimologia , Membrana Celular/metabolismo , Sobrevivência Celular , Meios de Cultivo Condicionados , Imunofluorescência , Fosfolipases A2 do Grupo II/antagonistas & inibidores , Humanos , Fluidez de Membrana/efeitos dos fármacos , Fluidez de Membrana/fisiologia , Microscopia de Fluorescência , Neurônios/efeitos dos fármacos , Fragmentos de Peptídeos/metabolismo
17.
Am J Transplant ; 15(8): 2188-96, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25877792

RESUMO

Primary graft dysfunction (PGD) is a major cause of early mortality after lung transplant. We aimed to define objective estimates of PGD risk based on readily available clinical variables, using a prospective study of 11 centers in the Lung Transplant Outcomes Group (LTOG). Derivation included 1255 subjects from 2002 to 2010; with separate validation in 382 subjects accrued from 2011 to 2012. We used logistic regression to identify predictors of grade 3 PGD at 48/72 h, and decision curve methods to assess impact on clinical decisions. 211/1255 subjects in the derivation and 56/382 subjects in the validation developed PGD. We developed three prediction models, where low-risk recipients had a normal BMI (18.5-25 kg/m(2) ), chronic obstructive pulmonary disease/cystic fibrosis, and absent or mild pulmonary hypertension (mPAP<40 mmHg). All others were considered higher-risk. Low-risk recipients had a predicted PGD risk of 4-7%, and high-risk a predicted PGD risk of 15-18%. Adding a donor-smoking lung to a higher-risk recipient significantly increased PGD risk, although risk did not change in low-risk recipients. Validation demonstrated that probability estimates were generally accurate and that models worked best at baseline PGD incidences between 5% and 25%. We conclude that valid estimates of PGD risk can be produced using readily available clinical variables.


Assuntos
Transplante de Pulmão , Disfunção Primária do Enxerto , Adulto , Feminino , Humanos , Masculino , Fatores de Risco
18.
Free Radic Res ; 49(5): 583-98, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25734631

RESUMO

Isoprostanoids are a group of non-enzymatic oxidized lipids from polyunsaturated fatty acids. They are commonly used as biomarkers for oxidative damage, to assess in vivo lipid peroxidation in diseases related to the vascular system and neurodegeneration. Currently, there is a mismatch with the outcome in the use of these biomarkers in intervention studies, particularly when testing the effect of antioxidants such as vitamins C and E, or zinc, or a cocktail of these, with other food components. Much of this is because the biomarkers, the method of measurement, and the duration of supplementation are unsuitable. In this review, we will highlight the formation of isoprostanoids from their respective fatty acids, and their application as biomarkers for oxidative damage in vivo, considering human dietary intervention studies evaluating plasma and urine, using mass spectrometry techniques.


Assuntos
Antioxidantes/uso terapêutico , Dieta , Suplementos Nutricionais , Isoprostanos/metabolismo , Espectrometria de Massas , Estresse Oxidativo/efeitos dos fármacos , Animais , Biomarcadores/metabolismo , Cromatografia Líquida , Dieta/efeitos adversos , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Isoprostanos/sangue , Isoprostanos/urina , Peroxidação de Lipídeos/efeitos dos fármacos , Espectrometria de Massas/métodos , Avaliação Nutricional , Estado Nutricional , Oxirredução , Valor Preditivo dos Testes , Espectrometria de Massas em Tandem , Resultado do Tratamento
19.
J Dent Res ; 94(6): 828-35, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25818583

RESUMO

Transforming growth factor ß (TGF-ß) signaling has been implicated in dentin formation and repair; however, the molecular mechanisms underlying dentin formation remain unclear. To address the role of TGF-ß signaling in dentin formation, we analyzed odontoblast-specific Tgfbr2 conditional knockout mice. The mutant mice had aberrant teeth with thin dysplastic dentin and pulpal obliteration, similar to teeth from human patients with dentinogenesis imperfecta type II and dentin dysplasia. In mutant, the odontoblasts lost their cellular polarity, and matrix secretion was disrupted after mantle dentin formation. As a consequence, the amount of predentin decreased significantly, and an ectopic fibrous matrix was formed below the odontoblast layer. This matrix gradually calcified and obliterated the pulp chamber with increasing age. Immunohistochemistry revealed decreased expression of alkaline phosphatase in mutant odontoblasts. In mutant dentin, Dsp expression was reduced, but Dmp1 expression increased significantly. Collagen type I, biglycan, and Dsp were expressed in the ectopic matrix. These results suggest that loss of responsiveness to TGF-ß in odontoblasts results in impaired matrix formation and pulpal obliteration. Our study indicates that TGF-ß signaling plays an important role in dentin formation and pulp protection. Furthermore, our findings may provide new insight into possible mechanisms underlying human hereditary dentin disorders and reparative dentin formation.


Assuntos
Calcificações da Polpa Dentária/genética , Odontoblastos/metabolismo , Proteínas Serina-Treonina Quinases/genética , Receptores de Fatores de Crescimento Transformadores beta/genética , Fosfatase Alcalina/análise , Animais , Biglicano/análise , Polaridade Celular/genética , Colágeno Tipo I/análise , Displasia da Dentina/genética , Dentinogênese/genética , Dentinogênese Imperfeita/genética , Desmoplaquinas/análise , Matriz Extracelular/química , Matriz Extracelular/metabolismo , Proteínas da Matriz Extracelular/análise , Camundongos , Camundongos Knockout , Odontoblastos/patologia , Proteínas Serina-Treonina Quinases/fisiologia , Receptor do Fator de Crescimento Transformador beta Tipo II , Receptores de Fatores de Crescimento Transformadores beta/fisiologia , Transdução de Sinais/genética , Fator de Crescimento Transformador beta/fisiologia
20.
Clin Otolaryngol ; 40(4): 355-62, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25639297

RESUMO

OBJECTIVE: Recent reports have identified hypercholesterolaemia as a significant risk factor for idiopathic sudden sensorineural hearing loss (ISSNHL). Therefore, we investigated whether lipid profiles and lipoprotein ratios are correlated with the prognosis of hearing recovery in ISSNHL patients. DESIGN: A retrospective cohort study. MAIN OUTCOME MEASURES: Patients with ISSNHL were classified into four groups (complete, partial, slight and no recovery) according to their degree of hearing recovery using Siegel's criteria and the Sudden Deafness Research Group (SDRG) criteria developed by the Japanese Ministry of Welfare. All patients' lipid profiles were analysed, including total cholesterol (TC), high-density lipoprotein (HDL) and low-density lipoprotein (LDL) cholesterol and triglycerides. We calculated the ratios of TC/HDL-C and LDL-C/HDL-C and used statistical methods to evaluate correlations between lipid profiles and lipoprotein ratios and ISSNHL prognosis. RESULTS: Hearing recovery was observed in 103 (62.0%) of 166 cases using Siegel's criteria and in 114 (68.7%) of 166 cases using SDRG's criteria. Among the three recovery groups (i.e. excluding the no recovery group), the ratio of LDL-C/HDL-C was found to be associated with recovery outcome by showing the ratio on an upward trend from complete recovery to slight recovery group, and the difference is statistically significant (P = 0.016 by Siegel's criteria, P = 0.041 by SDRG's criteria). Multiple linear regression analysis further revealed a significantly higher LDL-C/HDL-C ratio in slight hearing recovery group compared with complete recovery group (P = 0.007 by Siegel's criteria, P = 0.031 by SDRG's criteria). CONCLUSION: We suggested that lipoprotein ratio of LDL-C/HDL-C may be a prognostic factor for hearing recovery in ISSNHL patients. Further studies should be conducted to determine whether hearing outcomes in ISSNHL can be improved by changing patients' lipid profiles via antilipidemic treatment.


Assuntos
Perda Auditiva Neurossensorial/etiologia , Perda Auditiva Súbita/etiologia , Hiperlipidemias/complicações , Feminino , Perda Auditiva Neurossensorial/classificação , Perda Auditiva Súbita/classificação , Humanos , Lipoproteínas HDL/sangue , Lipoproteínas LDL/sangue , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento
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