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1.
J Cell Mol Med ; 26(4): 1013-1023, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35014181

RESUMO

YAP1, a key mediator of the Hippo pathway, plays an important role in tumorigenesis. Alternative splicing of human YAP1 mRNA results in two major isoforms: YAP1-1, which contains a single WW domain, and YAP1-2, which contains two WW domains, respectively. We here investigated the functions and the underlying regulatory mechanisms of the two YAP1 isoforms in the context of EGF-induced epithelial-mesenchymal transition (EMT) in non-small cell lung cancer (NSCLC). Human NSCLC cell lines express both YAP1-1 and YAP1-2 isoforms-although when compared to YAP1-1, YAP1-2 mRNA levels are higher while its protein expression levels are lower. EGF treatment significantly promoted YAP1 expression as well as EMT process in NSCLCs, whereas EGF-induced EMT phenotype was significantly alleviated upon YAP1 knockdown. Under normal culture condition, YAP1-1 stable expression cells exhibited a stronger migration ability than YAP1-2 expressing cells. However, upon EGF treatment, YAP1-2 stable cells showed more robust migration than YAP1-1 expressing cells. The protein stability and nuclear localization of YAP1-2 were preferentially enhanced with EGF treatment. Moreover, EGF-induced EMT and YAP1-2 activity were suppressed by inhibitor of AKT. Our results suggest that YAP1-2 is the main isoform that is functionally relevant in promoting EGF-induced EMT and ultimately NSCLC progression.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Linhagem Celular Tumoral , Fator de Crescimento Epidérmico/metabolismo , Fator de Crescimento Epidérmico/farmacologia , Transição Epitelial-Mesenquimal/genética , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteínas de Sinalização YAP
2.
Braz J Med Biol Res ; 54(10): e11355, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34287582

RESUMO

The etiology of subacute combined degeneration (SCD) of the spinal cord is closely associated with vitamin B12 (VitB12) deficiency. The clinical manifestations of SCD are complex and vary substantially. Due to some SCD patients with atypical manifestations and concomitant autoimmune disorders, the probability of misdiagnosis and missed diagnosis is still relatively high in the early stage. We report the cases of two patients who were missed or misdiagnosed at another hospital because of the normal initial VitB12 level and partial overlap of clinical manifestations, finally diagnosed as SCD with atypical manifestations and concomitant autoimmune disorders, pharyngeal-cervical-brachial Guillain-Barre syndrome in Case 1 and SCD with autoimmune thyroiditis in Case 2. After undergoing corresponding treatment, death was reported in Case 1 and improvement in Case 2. Analysis of the clinical manifestations and investigation of the underlying pathogenesis in such patients could help improve the rate of early diagnosis and allow timely treatment of SCD, thereby preventing disease progression and poor clinical outcomes.


Assuntos
Doenças Autoimunes , Degeneração Combinada Subaguda , Doenças Autoimunes/complicações , Doenças Autoimunes/diagnóstico , Humanos , Imageamento por Ressonância Magnética , Medula Espinal , Degeneração Combinada Subaguda/complicações , Degeneração Combinada Subaguda/diagnóstico , Degeneração Combinada Subaguda/patologia , Vitamina B 12
3.
Front Oncol ; 11: 649290, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34094936

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is the most aggressive human malignancy and intrinsically resistant to conventional therapies. YAP1, as a key downstream effector of the Hippo pathway, plays an important role in tumorigenesis including PDAC. Alternative mRNA splicing of YAP1 results in at least 8 protein isoforms, which are divided into two subgroups (YAP1-1 and YAP1-2) based on the presence of either a single or double WW domains. We investigated the functions and regulatory mechanisms of YAP1-1 and YAP1-2 in PDAC cells induced by TGF-ß to undergo epithelial-to-mesenchymal transition (EMT). CRISPR-Cas9 and shRNA were used to silence YAP1 expression in pancreatic cancer cells. Re-constituted lentivirus mediated overexpression of each single YAP1 isoform was generated in the parental knockout L3.6 cells. EMT was induced by treatment with TGF-ß, EGF and bFGF in parental and the constructed stable cell lines. Western blot and qPCR were used to detect the expression of EMT markers. Scratch wound healing and transwell assays were used to detect cell migration. The stability and subcellular localization of YAP1 proteins were determined by Western blot analysis, immunofluorescence, as well as ubiquitination assays. We showed that TGF-ß, EGF and bFGF all significantly promoted EMT in PDAC cells, which was inhibited by knockdown of YAP1 expression. Interestingly, YAP1-1 stable cells exhibited a stronger migratory ability than YAP1-2 cells under normal culture condition. However, upon TGF-ß treatment, L3.6-YAP1-2 cells exhibited a stronger migratory ability than L3.6-YAP1-1 cells. Mechanistically, TGF-ß treatment preferentially stabilizes YAP1-2 and enhances its nuclear localization. Furthermore, TGF-ß-induced EMT and YAP1-2 activity were both blocked by inhibition of AKT signaling. Our results showed that both YAP1-1 and YAP1-2 isoforms are important mediators in the EMT process of pancreatic cancer. However, YAP1-2 is more important in mediating TGF-ß-induced EMT, which requires AKT signaling.

4.
Aging Dis ; 9(1): 8-16, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29392077

RESUMO

BACKGROUND: Parkinson's disease (PD) patients with 10 years or more survival (PD-10) are not well characterized. The aim of this study was to evaluate the main issues facing PD-10 patients and identify factors that independently contributed to quality of life (QoL). METHODS: A group of 121 PD-10 patients recruited from outpatient clinics participated in this cross-sectional study. Data on demographic and clinical factors were collected. Multiple linear regression analyses were conducted to identify determinants of poor QoL. RESULTS: The entire PD-10 patients had disease duration ranging from 10 to 23 years, with 84.2% of the total cohort skewed to between 10 and 15 years' duration. The PD-10 patients had great frequency of left-sided onset, increased motor and non-motor symptoms as well as inferior QoL. The more advanced stage of disease in PD-10 patients was associated with motor phenotype, freezing of gait, higher UPDRS sub-scores and levodopa equivalent dose, less balanced confidence, fatigue, anxiety, depression, reduced quality of life and worse Timed Up & Go performance. Self-reported mood symptoms, decreased balance confidence and reduced daily activities were the three factors most closely associated with poorer QoL, but excessive daytime sleepiness and long disease duration additionally contributed to the explanatory power. CONCLUSIONS: This is the first report to investigate the clinical characteristics of Chinese PD-10 patients. Our study may elucidate an important clue for understanding PD-10 patients in clinical practice and identifying patients with PD at risk for reduced QoL.

5.
Front Aging Neurosci ; 9: 308, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29021755

RESUMO

α-Synuclein misfolding and aggregation play an important role in the pathogenesis of Parkinson's disease (PD). Loss of function and mutation of the PARK7/DJ-1 gene cause early-onset familial PD. DJ-1 can inhibit α-synuclein aggregation, and may function at an early step in the aggregation process. Soluble wild-type (WT) α-synuclein is mainly degraded by chaperone-mediated autophagy (CMA), and impairment of CMA is closely related to the pathogenesis of PD. Here, we investigated whether DJ-1 could reduce α-synuclein accumulation and aggregation by CMA. DJ-1 knockout mice and DJ-1 siRNA knockdown SH-SY5Y cells were used to investigate the potential mechanisms underlying the relationship between DJ-1 deficiency and α-synuclein aggregation. First, we confirmed that DJ-1 deficiency increased the accumulation and aggregation of α-synuclein in both SH-SY5Y cells and PD animal models, and overexpression of DJ-1 in vitro effectively decreased α-synuclein levels. α-Synuclein overexpression activated CMA by elevating the levels of lysosome-associated membrane protein type-2A (LAMP2A), but DJ-1 deficiency suppressed upregulation of LAMP2A. DJ-1 deficiency downregulated the level of lysosomal 70 kDa heat-shock cognate protein (HSC70) but not the levels of that in homogenates. Further studies showed that DJ-1 deficiency accelerated the degradation of LAMP2A in lysosomes, leading to the aggregation of α-synuclein. Our study suggests that DJ-1 deficiency aggravates α-synuclein aggregation by inhibiting the activation of CMA and provides further evidence of the molecular interaction between PD-related proteins via the CMA pathway.

6.
Braz. j. med. biol. res ; 54(10): e11355, 2021. graf
Artigo em Inglês | LILACS | ID: biblio-1285647

RESUMO

The etiology of subacute combined degeneration (SCD) of the spinal cord is closely associated with vitamin B12 (VitB12) deficiency. The clinical manifestations of SCD are complex and vary substantially. Due to some SCD patients with atypical manifestations and concomitant autoimmune disorders, the probability of misdiagnosis and missed diagnosis is still relatively high in the early stage. We report the cases of two patients who were missed or misdiagnosed at another hospital because of the normal initial VitB12 level and partial overlap of clinical manifestations, finally diagnosed as SCD with atypical manifestations and concomitant autoimmune disorders, pharyngeal-cervical-brachial Guillain-Barre syndrome in Case 1 and SCD with autoimmune thyroiditis in Case 2. After undergoing corresponding treatment, death was reported in Case 1 and improvement in Case 2. Analysis of the clinical manifestations and investigation of the underlying pathogenesis in such patients could help improve the rate of early diagnosis and allow timely treatment of SCD, thereby preventing disease progression and poor clinical outcomes.


Assuntos
Humanos , Doenças Autoimunes/complicações , Doenças Autoimunes/diagnóstico , Degeneração Combinada Subaguda/complicações , Degeneração Combinada Subaguda/diagnóstico , Degeneração Combinada Subaguda/patologia , Medula Espinal , Vitamina B 12 , Imageamento por Ressonância Magnética
7.
Aging Dis ; 7(3): 230-6, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27330837

RESUMO

The G2385R variant of the leucine-rich repeat kinase 2 (LRRK2) is strongly associated with Parkinson's disease (PD) in Asian populations. However, it is still unclear whether the clinical phenotype of PD patients with the G2385R variant can be distinguished from that of patients with idiopathic PD. In this study, we investigated motor and non-motor symptoms of LRRK2 G2385R variant carriers in a Chinese population. We genotyped 1031 Chinese PD patients for the G2385R variant of the LRRK2 gene, and examined the demographic and clinical characteristics of LRRK2 G2385R variant carrier and non-carrier PD patients. LRRK2 G2385R variant carriers were more likely to present the postural instability and gait difficulty dominant (PIGD) phenotype. This variant was also significantly associated with motor fluctuations and the levodopa equivalent dose (LED). G2385R variant carriers had higher REM sleep behavior disorder (RBD) screening questionnaire (RBDSQ) score and more RBD symptoms compared with non-carriers. We concluded that the G2385R variant could be a risk factor for the PIGD phenotype, motor fluctuations, LED values and RBD symptoms.

8.
J Neuroimmune Pharmacol ; 8(1): 356-69, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23325107

RESUMO

Parkinson's disease (PD) is pathologically characterized by the presence of α-synuclein positive intracytoplasmic inclusions. The missense mutation, A53T α-synuclein is closely related to hereditary, early-onset PD. Accumulating evidences suggest that pathological accumulation of A53T α-synuclein protein will perturb itself to be efficiently and normally degraded through its usual degradation pathway, macroautophagy-lysosome pathway, therefore toxic effects on the neuron will be exacerbated. Based on the above fact, we demonstrated in this study that A53T α-synuclein overexpression impairs macroautophagy in SH-SY5Y cells and upregulates mammalian target of rapamycin (mTOR)/p70 ribosomal protein S6 kinase (p70S6K) signaling, the classical suppressive pathway of autophagy. We further found that curcumin, a natural compound derived from the curry spice turmeric and with low toxicity in normal cells, could efficiently reduce the accumulation of A53T α-synuclein through downregulation of the mTOR/p70S6K signaling and recovery of macroautophagy which was suppressed. These findings suggested that the regulation of mTOR/p70S6K signaling may be a participant of the accumulation of A53T α-synuclein protein-linked Parkinsonism. Meanwhile curcumin could be a candidate neuroprotective agent by inducing macroautophagy, and needs to be further investigated by clinical application in patients suffering Parkinson's disease.


Assuntos
Autofagia/efeitos dos fármacos , Curcumina/farmacologia , Macrófagos/efeitos dos fármacos , Doenças Neurodegenerativas/tratamento farmacológico , Doenças Neurodegenerativas/patologia , Fármacos Neuroprotetores , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/patologia , Proteínas Quinases S6 Ribossômicas 70-kDa/fisiologia , Serina-Treonina Quinases TOR/fisiologia , alfa-Sinucleína/fisiologia , Adenina/análogos & derivados , Adenina/farmacologia , Western Blotting , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Vetores Genéticos , Humanos , Imuno-Histoquímica , Transfecção
9.
Neurosci Bull ; 28(5): 649-57, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22961477

RESUMO

Parkinson's disease (PD) is pathologically characterized by the presence of α-synuclein (α-syn)-positive intracytoplasmic inclusions named Lewy bodies in the dopaminergic neurons of the substantia nigra. A series of morbid consequences are caused by pathologically high amounts or mutant forms of α-syn, such as defects of membrane trafficking and lipid metabolism. In this review, we consider evidence that both point mutation and overexpression of α-syn result in aberrant degradation in neurons and microglia, and this is associated with the autophagy-lysosome pathway and endosome-lysosome system, leading directly to pathological intracellular aggregation, abnormal externalization and re-internalization cycling (and, in turn, internalization and re-externalization), and exocytosis. Based on these pathological changes, an increasing number of researchers have focused on these new therapeutic targets, aiming at alleviating the pathological accumulation of α-syn and re-establishing normal degradation.


Assuntos
Antiparkinsonianos/metabolismo , Sistemas de Liberação de Medicamentos/métodos , Lisossomos/genética , Doença de Parkinson/genética , Transdução de Sinais/genética , alfa-Sinucleína/metabolismo , Animais , Antiparkinsonianos/administração & dosagem , Autofagia/efeitos dos fármacos , Autofagia/genética , Regulação da Expressão Gênica/genética , Humanos , Lisossomos/efeitos dos fármacos , Lisossomos/patologia , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/patologia , Mutação Puntual/genética , Transdução de Sinais/efeitos dos fármacos , alfa-Sinucleína/antagonistas & inibidores , alfa-Sinucleína/genética
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