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1.
APMIS ; 127(12): 746-752, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31520423

RESUMO

Meningiomas are common intracranial tumors, and most exhibit optimal prognosis; however, some meningiomas still recur and even develop malignant transformation in the following years, regardless of initial pathological grade. During these years, autophagy raises its significance in tumorigenesis and tumor suppression, both important for tumor development. The aim of this study was to elucidate the relationship between two autophagy markers, LC3B and beclin 1, with clinical and pathological parameters in patients with meningiomas. A total of 77 thin-sectioned slides, retrospectively collected from meningioma patients, were analyzed and correlated with clinicopathological parameters. We found that expression of beclin 1 rather than LC3B correlated to better prognosis, lower pathological grade, and longer survival. Furthermore, intensity of beclin 1 was also found to be significantly related to the pathological grade. These findings indicated that beclin 1 as a protective factor predicts better prognosis and plays the role of tumor suppression in meningiomas.


Assuntos
Proteína Beclina-1/genética , Proteína Beclina-1/metabolismo , Neoplasias Meníngeas/fisiopatologia , Meningioma/fisiopatologia , Feminino , Humanos , Imuno-Histoquímica , Masculino , Neoplasias Meníngeas/metabolismo , Neoplasias Meníngeas/mortalidade , Meningioma/metabolismo , Meningioma/mortalidade , Proteínas Associadas aos Microtúbulos/metabolismo , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida
2.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 35(7): 613-618, 2019 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-31537246

RESUMO

Objective To investigate the effect of baicalein (BAI) on autophagy in gastric cancer cell line MGC-803. Methods MGC-803 cells were treated with 0, 5, 15, 25, 50 µmol/L BAI for 24, 48, 72 hours. The proliferation activity of MGC-803 cells was detected by MTT assay. Acridine orange (AO) staining combined with immunofluorescence cytochemical staining was performed to observe the expression of microtubule-associated protein 1 light chain 3 (LC3) and P62 to determine autophagy in MGC-803 cells. The protein levels of LC3, P62, phosphatidylinositol 3-kinase (PI3K), phosphorylated PI3K (p-PI3K), AKT, and p-AKT were detected by Western blot analysis. Results Compared with the control group, BAI significantly inhibited the proliferation of MGC-803 cells in a time- and dose-dependent manner. BAI-treated MGC-803 cells showed a significant increase in acid lysosomes and increased LC3 expression. BAI treatment significantly decreased phosphorylation of PI3K and AKT proteins, increased the ratio of LC3-II/LC3-I and up-regulated the expression of P62 protein. Conclusion Baicalein could inhibit PI3K/AKT signaling pathway and induce autophagy in MGC-803 cells.


Assuntos
Autofagia , Flavanonas/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Linhagem Celular Tumoral , Proliferação de Células , Humanos , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas de Ligação a RNA/metabolismo
3.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 35(7): 619-624, 2019 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-31537247

RESUMO

Objective To investigate the effects of Astragalus polysaccharide (APS) on autophagy and expression of microtubule-associated protein 1 light chain 3B (LC3B), mammalian target of rapamycin (mTOR) and beclin1 in xanthine oxidase (XOD)-induced autophagic model of non-small cell lung cancer A549 cells. Methods A549 cells were divided into five groups: control group, model group, 100, 200 and 400 µg/mL APS-treated group. Except for control group, all groups were administered XOD for 24 hours to establish autophagic models. Morphology of autophagosome was detected by transmission electron microscopy (TEM) and the number was counted by monodansylcadaverine (MDC) staining. The expression levels of LC3B, beclin1 and mTOR were detected by Western blot analysis. Results Compared with the control group, the number of autophagosome in the model group increased; the expression of LC3B and beclin1 significantly increased; while the expression of mTOR significantly decreased. Compared with the model group, the number of autophagosome decreased remarkably; the expression of LC3B and beclin1 severely decreased, and the expression of mTOR obviously increased in 200 or 400 µg/mL APS-treated group. Conclusion APS reduces the level of autophagy, down-regulates the expression of LC3B and beclin1, and increases mTOR expression in the autophagic model of A549 cells induced by XOD.


Assuntos
Astrágalo (Planta)/química , Autofagia , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/patologia , Polissacarídeos/farmacologia , Células A549 , Proteínas Relacionadas à Autofagia , Proteína Beclina-1/metabolismo , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Humanos , Neoplasias Pulmonares/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Xantina Oxidase
4.
Zhonghua Zhong Liu Za Zhi ; 41(7): 522-526, 2019 Jul 23.
Artigo em Chinês | MEDLINE | ID: mdl-31357839

RESUMO

Objective: To investigate the expression of nucleolar and spindle-associated protein 1 (NUSAP1) in non-small cell lung cancer (NSCLC) and analyze its relationship with the prognosis of NSCLC patients. Methods: Real-time fluorescent quantitative PCR and immunohistochemical staining were performed to determine the expression of NUSAP1 in NSCLC tissues and adjacent tissues collected from hospital. The relationship between NUSAP1 expression and prognosis of NSCLC patients was analyzed by online database. Results: The expression level of NUSAP1 mRNA in tumor tissues was significantly higher than that of adjacent tissues (P<0.05). The high expression rate of NUSAP1 protein in NSCLC tissues was 58.0% (29/50), significantly higher than 22.0% (11/50) of adjacent tissues (P<0.05). The high expression of NUSAP1 protein in NSCLC tissues was closely correlated with tumor size, lymph node metastasis and TNM stage (P<0.05), but was not related to age and gender. The data showed that the expression level of NUSAP1 mRNA was inversely associated with the overall survival (OS) of NSCLC patients (P<0.001). The expression of NUSAP1 mRNA was significantly correlated with the pathological grade, clinical stage, gender, chemotherapy, smoking history, and histological type of NSCLC patients (P<0.05). Conclusions: The expression of NUSAP1 is up-regulated in NSCLC, which is correlated with the growth and development of NSCLC and prognosis of the patients. These results indicate that NUSAP1 can be used as a potential prognostic marker for NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/metabolismo , Neoplasias Pulmonares/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Biomarcadores Tumorais , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Metástase Linfática , Proteínas Associadas aos Microtúbulos/genética , Prognóstico
5.
Anticancer Res ; 39(7): 3687-3695, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31262895

RESUMO

BACKGROUND: Neuroblastoma is the main solid extracranial tumor of childhood. The amplification of N-myc oncogene (MYCN) and 1p deletion are the main molecular alterations. These features are what make treatment impossible, especially in high-risk patients with metastases. MATERIALS AND METHODS: Our study investigated the processes undergone by CHP-212 neuroblastoma cells, after being treated with Casiopeínas® (Cas) IIgly, IIIEa, and IIIia for 2, 10, and 24 h. RESULTS: At 2 h, all the treatments Ied to apoptosis [defined by the presence of B-cell lymphoma 2 (BCL2), BCL2-associated X protein, cytochrome c, and caspase-3]. In addition, autophagy with specific molecules beclin-1 and microtubule-associated protein 1A/1B-light chain 3 (LC3)-II/LC3-I (ratio >1). Later at 10 h, autophagy-associated proteins were observed, and at 24 h, only survival proteins nuclear factor kappa-light-chain-enhancer of activated B-cells (NF-κB), and extracellular signal-regulated kinases (ERK)2/ERK1>1 were found. Another relevant finding was the presence of caspase-10 throughout the study, especially in cells treated with CasIIgly and CasIIIEa. CONCLUSION: These relationships indicate a possible mechanism of action of Casiopeínas on neuroblastoma.


Assuntos
Complexos de Coordenação/farmacologia , Neuroblastoma/metabolismo , Fenantrolinas/farmacologia , Autofagia/efeitos dos fármacos , Proteína Beclina-1/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Citocromos c/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Humanos , Proteínas Associadas aos Microtúbulos/metabolismo , Neuroblastoma/tratamento farmacológico , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo
6.
Toxicol Lett ; 314: 142-152, 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31319114

RESUMO

Cadmium (Cd), an established carcinogen, is a risk factor for oral squamous cell carcinoma (OSCC). Macroautophagy/autophagy is proposed to play a pivotal role in Cd-mediated carcinogenic activity. However, the mechanisms underlying Cd-induced autophagy are poorly understood. In the present study, a CAL27 OSCC cell line exposed to 10-6 M Cd for 8 weeks was used as a model system. Repeated Cd exposure induced significant migration and invasion of CAL27 cells. Furthermore, we showed that Cd increased the autophagic flux in CAL27 cells, as evidenced by the upregulation of LC3-II and the downregulation of P62/SQSTM1. The genetic blocking of autophagy inhibited Cd-induced migration and invasion, indicating a carcinogenic role of autophagy in Cd-treated CAL27 cells. Cd-induced NUPR1 expression, which contributes to lysosomal biogenesis and expression of autophagy-related gene, was found to mechanistically initiate autophagy in CAL27 cells. Of note, NUPR1 shRNA abolished Cd-induced autophagy both in vitro and in vivo. We also found that Cd triggered the generation of MDA in a xenograft tumour model and that N-acetyl-l-cysteine, a reactive oxygen species (ROS) scavenger, abrogated the effects of Cd on NUPR1-dependent autophagy in vivo. Taken together, these results demonstrate that ROS-dependent NUPR1-mediated autophagy plays an important role in repeated Cd exposure -induced cell growth, migration and invasion in OSCC cells.


Assuntos
Acetilcisteína/farmacologia , Antioxidantes/farmacologia , Autofagia/efeitos dos fármacos , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Cloreto de Cádmio/toxicidade , Movimento Celular/efeitos dos fármacos , Neoplasias Bucais/tratamento farmacológico , Proteínas de Neoplasias/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Animais , Proteína 5 Relacionada à Autofagia/genética , Proteína 5 Relacionada à Autofagia/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Masculino , Camundongos Nus , Proteínas Associadas aos Microtúbulos/metabolismo , Neoplasias Bucais/genética , Neoplasias Bucais/metabolismo , Neoplasias Bucais/patologia , Invasividade Neoplásica , Proteínas de Neoplasias/genética , Proteína Sequestossoma-1/metabolismo , Transdução de Sinais , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
7.
Chem Biol Interact ; 311: 108762, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31348917

RESUMO

Neurotoxicity caused by particulate matter (PM) has been highlighted as being a potential risk factor for neurodegenerative diseases. However, the effects of brain inflammation in response to traffic-related PM remain unclear. The objective of this study was to investigate the effects of traffic-related PM on microglial responses. We determined the cytotoxicity, oxidative stress, lipid peroxidation, inflammation, activation, autophagy, and apoptosis due to exposure to carbon black (CB) and diesel exhaust particles (DEPs) in Bv2 microglial cells. Additionally, cells were pretreated with corticosteroid to determine alterations in microglial activation and inflammation. For in vivo confirmation, Sprague Dawley (SD) rats were whole-body exposed to traffic-related PM1 (PM with an aerodynamic diameter of <1 µm) for 3 and 6 months. We observed that a decrease in cell viability and increases in dichlorodihydrofluorescein (DCFH), lactate dehydrogenase (LDH), and thiobarbituric acid-reactive substances (TBARSs) occurred due to CB and DEP. Production of interleukin (IL)-6 and soluble tumor necrosis factor (TNF)-α was significantly stimulated by CB and DEP, whereas production of cellular TNF-α was significantly stimulated by CB. Iba1 and prostaglandin E2 (PGE2) significantly increased due to CB and DEP. Consistently, we observed significant increases in Iba1 in the hippocampus of rats after 3 and 6 months of exposure to traffic-related PM1. We found that the light chain 3II (LC3II)/LC3I ratio and caspase-3 activity increased due to CB and DEP exposure. Subsequently, LDH, TBARS, LC3II/I, and caspase-3 activities did not clearly respond to corticosteroid pretreatment followed by DEP exposure in BV2 cells. Results of the present study suggested that traffic-related PM induced cytotoxicity, lipid peroxidation, microglial activation, and inflammation as well as autophagy and caspase-3 regulation in microglia. We demonstrated that microglial activation and inflammation may play important roles in the response of the brain to traffic-related PM.


Assuntos
Inflamação/etiologia , Microglia/efeitos dos fármacos , Material Particulado/toxicidade , Animais , Autofagia/efeitos dos fármacos , Encéfalo/patologia , Proteínas de Ligação ao Cálcio/análise , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Dinoprostona/análise , Interleucina-6/metabolismo , L-Lactato Desidrogenase/metabolismo , Masculino , Proteínas dos Microfilamentos/análise , Microglia/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Fator de Necrose Tumoral alfa/metabolismo , Regulação para Cima/efeitos dos fármacos , Emissões de Veículos/toxicidade
8.
Medicine (Baltimore) ; 98(30): e16534, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31348270

RESUMO

BACKGROUND: High-grade prostate cancer (PCa) has a poor prognosis, and up to 15% of patients worldwide experience lymph node invasion (LNI). To further improve the prediction lymph node invasion in prostate cancer, we adopted risk scores of the genes expression based on the nomogram in guidelines. METHODS: We analyzed clinical data from 320 PCa patients from the Cancer Genome Atlas database. Weighted gene coexpression network analysis was used to identify the genes that were significantly associated with LNI in PCa (n = 390). Analyses using the Gene Ontology and Kyoto Encyclopedia of Genes and Genomes databases were performed to identify the activated signaling pathways. Univariate and multivariate logistic regression analyses were performed to identify the independent risk factors for the presence of LNI. RESULTS: We found that patients with actual LNI and predicted LNI had the worst survival outcomes. The 7 most significant genes (CTNNAL1, ENSA, MAP6D1, MBD4, PRCC, SF3B2, TREML1) were selected for further analysis. Pathways in the cell cycle, DNA replication, oocyte meiosis, and 9 other pathways were dramatically activated during LNI in PCa. Multivariate analyses identified that the risk score (odds ratio [OR] = 1.05 for 1% increase, 95% confidence interval [CI]: 1.04-1.07, P < .001), serum PSA level, clinical stage, primary biopsy Gleason grade (OR = 2.52 for a grade increase, 95% CI: 1.27-5.22, P = .096), and secondary biopsy Gleason grade were independent predictors of LNI. A nomogram built using these predictive variables showed good calibration and a net clinical benefit, with an area under the curve (AUC) value of 90.2%. CONCLUSIONS: In clinical practice, the application of our nomogram might contribute significantly to the selection of patients who are good candidates for surgery with extended pelvic lymph node dissection.


Assuntos
Biomarcadores Tumorais/genética , Metástase Linfática/genética , Nomogramas , Neoplasias da Próstata/genética , Idoso , Área Sob a Curva , Proteínas de Ciclo Celular/metabolismo , Bases de Dados Genéticas , Endodesoxirribonucleases/metabolismo , Humanos , Modelos Logísticos , Linfonodos/patologia , Masculino , Proteínas Associadas aos Microtúbulos/metabolismo , Pessoa de Meia-Idade , Análise Multivariada , Gradação de Tumores , Proteínas de Neoplasias/metabolismo , Razão de Chances , Peptídeos/metabolismo , Valor Preditivo dos Testes , Neoplasias da Próstata/patologia , Fatores de Processamento de RNA/metabolismo , Receptores Imunológicos/metabolismo , Reprodutibilidade dos Testes , Fatores de Risco , alfa Catenina/metabolismo
9.
Life Sci ; 232: 116627, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31276690

RESUMO

AIM: Evidence suggests that task-specific gait training improves locomotor impairments in people with incomplete spinal cord injury (SCI); however, plastic changes in brain areas remain poorly understood. The aim of this study was to examine the possible effects of a task-specific overground gait training on locomotor recovery and neuroplasticity markers in the cortex, cerebellum, and lumbar spinal cord in an experimental model of incomplete-SCI. MAIN METHODS: Using a blind, basic experimental design, 24 adult Wistar rats underwent a surgical procedure and were allocated into sham, non-trained SCI (SCI), and trained SCI (Tr-SCI) groups. On postoperative day 14, trained animals started a 4-week overground gait training program. All groups were subjected to weekly assessment of locomotor recovery of the hind limbs. On postoperative day 40, brain and lumbar spinal cord structures were dissected and processed for biochemical analysis of the synaptophysin, microtubule-associated protein 2 (MAP-2), and brain-derived neurotrophic factor (BDNF). KEY FINDINGS: Tr-SCI group showed greater locomotor function recovery compared with non-trained SCI from the postoperative day 21 (p < 0.05). The training was able to improve the neuroplasticity markers synaptophysin, MAP-2, and BDNF expressions in motor cortex (p < 0.05), but not in the cerebellum and in the spinal cord for trained SCI group compared to non-trained. SIGNIFICANCE: Task-specific overground gait training improves locomotor recovery in a rat model of incomplete thoracic-SCI. Furthermore, training promotes motor cortex plasticity, evidenced for increasing expression of the neuroplasticity markers that may support the functional recovery.


Assuntos
Terapia por Exercício/métodos , Locomoção/fisiologia , Animais , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Modelos Animais de Doenças , Feminino , Marcha/fisiologia , Masculino , Proteínas Associadas aos Microtúbulos/metabolismo , Atividade Motora , Plasticidade Neuronal/fisiologia , Ratos , Ratos Wistar , Recuperação de Função Fisiológica , Medula Espinal/metabolismo , Traumatismos da Medula Espinal/metabolismo , Traumatismos da Medula Espinal/terapia
10.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 37(2): 168-173, 2019 Apr 01.
Artigo em Chinês | MEDLINE | ID: mdl-31168983

RESUMO

OBJECTIVE: To investigate the expression of autophagy-related protein Beclin-1 and microtubule-associated protein 2 light chain 3 (LC3Ⅱ) in periodontal ligament cells in orthodontic tooth pressure areas. METHODS: Sixty male SD rats were randomly divided into a blank control group and nine experimental groups. In the experimental groups, 0.392 N orthodontic force was used to move the first right upper molars for 15 min, 30 min, 1 h, 2 h, 4 h, 12 h, 1 d, 3 d, or 7 d. The blank control group did not receive any treatment. The rats were euthanized. Changes in the morphology of the periodontal membrane in the pressure areas were observed through hematoxylin and eosin (HE) staining. The expression levels of Beclin-1 and LC3Ⅱ were detected by immunohistochemical staining, and tartrate-resistant acid phosphatase (TRAP) staining was performed for the counting of osteoclasts. RESULTS: The HE stains showed that the hyalinization of the periodontal ligament appeared in the pressure areas after 1 day of exertion and was gradually aggravated. The immunohistochemical stains showed that the expression levels of Beclin-1 and LC3Ⅱ in the experimental groups gradually increased, peaked after 1 h, and then gradually decreased. The expression levels peaked again after 1 d, then decreased to baseline levels at 7 d of exertion. Beclin-1 and LC3Ⅱ were expressed in the osteoclasts. The TRAP stains indicated that the number of osteoclasts started to increase after 1 day. CONCLUSIONS: Autophagy may participate in the process of periodontal ligament reconstruction in orthodontic tooth pressure areas by mediating the hyalinization of periodontal ligament and affecting the biological effects of osteoclasts.


Assuntos
Autofagia , Proteínas Associadas aos Microtúbulos , Ligamento Periodontal , Animais , Proteína Beclina-1/metabolismo , Masculino , Proteínas Associadas aos Microtúbulos/metabolismo , Osteoclastos , Ligamento Periodontal/metabolismo , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Técnicas de Movimentação Dentária
11.
Nat Commun ; 10(1): 2612, 2019 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-31197141

RESUMO

Primary microcephaly is caused by mutations in genes encoding centrosomal proteins including WDR62 and KIF2A. However, mechanisms underlying human microcephaly remain elusive. By creating mutant mice and human cerebral organoids, here we found that WDR62 deletion resulted in a reduction in the size of mouse brains and organoids due to the disruption of neural progenitor cells (NPCs), including outer radial glia (oRG). WDR62 ablation led to retarded cilium disassembly, long cilium, and delayed cell cycle progression leading to decreased proliferation and premature differentiation of NPCs. Mechanistically, WDR62 interacts with and promotes CEP170's localization to the basal body of primary cilium, where CEP170 recruits microtubule-depolymerizing factor KIF2A to disassemble cilium. WDR62 depletion reduced KIF2A's basal body localization, and enhanced KIF2A expression partially rescued deficits in cilium length and NPC proliferation. Thus, modeling microcephaly with cerebral organoids and mice reveals a WDR62-CEP170-KIF2A pathway promoting cilium disassembly, disruption of which contributes to microcephaly.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Cinesina/metabolismo , Microcefalia/patologia , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Fosfoproteínas/metabolismo , Proteínas Repressoras/metabolismo , Animais , Técnicas de Cultura de Células , Proteínas de Ciclo Celular/genética , Diferenciação Celular , Linhagem Celular , Proliferação de Células , Cílios/metabolismo , Modelos Animais de Doenças , Feminino , Técnicas de Inativação de Genes , Humanos , Masculino , Camundongos , Camundongos Knockout , Microcefalia/genética , Proteínas Associadas aos Microtúbulos/genética , Proteínas do Tecido Nervoso/genética , Células-Tronco Neurais/citologia , Células-Tronco Neurais/patologia , Neuroglia/citologia , Neuroglia/patologia , Organoides/patologia , Fosfoproteínas/genética , RNA Interferente Pequeno/metabolismo
12.
Nat Commun ; 10(1): 2693, 2019 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-31217419

RESUMO

The kinesin-3 KIF1C is a fast organelle transporter implicated in the transport of dense core vesicles in neurons and the delivery of integrins to cell adhesions. Here we report the mechanisms of autoinhibition and release that control the activity of KIF1C. We show that the microtubule binding surface of KIF1C motor domain interacts with its stalk and that these autoinhibitory interactions are released upon binding of protein tyrosine phosphatase PTPN21. The FERM domain of PTPN21 stimulates dense core vesicle transport in primary hippocampal neurons and rescues integrin trafficking in KIF1C-depleted cells. In vitro, human full-length KIF1C is a processive, plus-end directed motor. Its landing rate onto microtubules increases in the presence of either PTPN21 FERM domain or the cargo adapter Hook3 that binds the same region of KIF1C tail. This autoinhibition release mechanism allows cargo-activated transport and might enable motors to participate in bidirectional cargo transport without undertaking a tug-of-war.


Assuntos
Cinesina/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas Tirosina Fosfatases não Receptoras/metabolismo , Animais , Transporte Biológico , Linhagem Celular , Vesículas Citoplasmáticas/metabolismo , Hipocampo/citologia , Humanos , Integrinas/metabolismo , Microscopia Intravital/métodos , Cinesina/genética , Cinesina/isolamento & purificação , Camundongos , Proteínas Associadas aos Microtúbulos/isolamento & purificação , Microtúbulos/metabolismo , Neurônios/citologia , Cultura Primária de Células , Ligação Proteica , Domínios Proteicos , Proteínas Tirosina Fosfatases não Receptoras/genética , Proteínas Tirosina Fosfatases não Receptoras/isolamento & purificação , RNA Interferente Pequeno/metabolismo , Ratos , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Imagem Individual de Molécula/métodos
13.
Food Chem Toxicol ; 131: 110555, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31173818

RESUMO

As a part of the aging process, N-retinylidene-N-retinylethanolamine (A2E) accumulates in the retina to activate autophagy in retinal pigmented epithelial cells. However, the effect of A2E photoactivation on autophagy, which is more clinically relevant, still remains unclear. Here, we investigated the effect of blue light (BL)-activated A2E on autophagy in human retinal pigmented epithelial cells, ARPE-19. A significant increase in LC3-II protein was observed when BL was irradiated on ARPE-19 cells containing A2E. The mammalian target of rapamycin (mTOR) pathway was examined to verify whether autophagy was activated, but no change in AKT, mTOR, and 4EBP phosphorylation was observed. Transcription factor EB (TFEB) target gene expression, which is another pathway involved in autophagy, was also not altered by A2E and BL. However, intracellular p62 protein levels were significantly increased, which represented the inhibition of autophagic flux. To investigate the mechanism of the suppressed autophagic flux, the lysosomal state was observed. After BL irradiation, lysosomal damage was induced in A2E-treated ARPE-19 cells, and this phenomenon was prevented by treatment with the antioxidant, N-acetylcysteine. Our results suggest that A2E photoactivation compromises autophagy in ARPE-19 cells and that reactive oxygen species (ROS) play an important role in this process.


Assuntos
Autofagia/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Epitélio Pigmentado da Retina/efeitos dos fármacos , Retinoides/toxicidade , Acetilcisteína/farmacologia , Linhagem Celular , Humanos , Luz , Lisossomos/efeitos dos fármacos , Proteínas Associadas aos Microtúbulos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Retinoides/efeitos da radiação
14.
Adv Clin Exp Med ; 28(7): 861-869, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31199877

RESUMO

BACKGROUND: Cytostatic treatment induces apoptosis or other types of cell death like autophagy, necrosis, mitotic catastrophe, etc. Autophagy can play a role in the drug resistance of neoplastic cells, allowing the survival of blast cells under stressful conditions, such as the use of cytostatics. Studies on apoptosis and autophagy 12-24 h after the start of treatment have not been conducted until now. OBJECTIVES: The study aimed to investigate the predictive and prognostic significance of autophagy and apoptosis in patients with acute myeloid leukemia (AML). MATERIAL AND METHODS: The study included 38 patients. Blood was collected before and 12-24 h after the start of treatment, since at that time point, the appropriate blast cell count was still available. Autophagy was measured with the expression of the ATG5, MAP1L3, LC3-I, and LC3-II proteins. The percentage of mononuclear cells in early and late apoptosis was evaluated with flow cytometry, using the annexin V and propidium iodide (PI) binding assay. RESULTS: The percentage of apoptotic blast cells before treatment was not associated with the response. However, in the remission group, the overall percentage of apoptotic cells measured 12-24 h after the start of treatment was higher than in non-remission patients, which was statistically significant. In neither group we found any difference in the level of autophagy before and 12-24 h after the start of treatment. Nevertheless, we observed an increasing tendency of the MAP1LC3 protein expression (not statistically significant) in the remission group 12-24 h after the start of treatment. Patients with a higher percentage of blast cells in apoptosis and with a higher expression of MAP1LC3 protein measured 12-24 h after the start of the therapy had longer overall survival (OS). CONCLUSIONS: A higher percentage of apoptotic as well as autophagic blast cells measured 12-24 h after the start of the chemotherapy is an independent factor associated with better outcomes.


Assuntos
Apoptose , Autofagia , Crise Blástica , Leucemia Mieloide Aguda , Proteínas Associadas aos Microtúbulos/metabolismo , Antineoplásicos/uso terapêutico , Citometria de Fluxo , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/mortalidade , Leucemia Mieloide Aguda/patologia , Prognóstico , Taxa de Sobrevida
15.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 35(4): 344-350; 356, 2019 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-31167694

RESUMO

Objective To investigate the mechanism of serine hydroxymethyl transferase 2 (SHMT2) inducing autophagy and promoting chemotherapy resistance in colon cancer cells. Methods TCGA database and real-time quantitative PCR were used to analyze the level of SHMT2 mRNA in colon cancer tissues. Western blot analysis and immunohistochemistry were used to detect the expression and distribution of SHMT2 in colon cancer tissues. Western blot analysis was performed to detect the SHMT2 protein levels of SW480, SW620, HCT116, CACO2, RKO, HCT8, HT15 and HT29 cells. After over-expression of SHMT2 in CACO2 colon cancer cells, MTT assay was used to detect cell viability, and annexin V-FITC/PI double labeling was used to detect the apoptosis of colon cancer cells induced by 5-fluorouracil (5-Fu). The autophagosomes of colon cancer cells were observed by transmission electron microscopy. The protein levels of LC3 II/I, P62, cleaved PARP (c-PARP), and cleaved caspase-3 (c-caspase-3) were examined by Western blot analysis. Signaling Phospho-Antibody Array and Western blot analysis were applied to analyze the phosphorylation level of AMPK/mTOR. Results SHMT2 was highly expressed in colon cancer tissues and cells. Over-expression of SHMT2 significantly increased cell viability and the ratio of LC3 II/ LC3 I. It was found that the phosphorylation level of AMPK was raised and the phosphorylation level of mTOR was reduced after the over-expression of SHMT2. Conclusion SHMT2 may induce autophagy by promoting AMPK phosphorylation and directly or indirectly inhibiting mTOR activity, thus leading to chemotherapy-induced apoptosis tolerance and resistance to chemotherapeutics.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Autofagia , Neoplasias do Colo/enzimologia , Resistencia a Medicamentos Antineoplásicos , Glicina Hidroximetiltransferase/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Apoptose , Células CACO-2 , Neoplasias do Colo/tratamento farmacológico , Humanos , Proteínas Associadas aos Microtúbulos/metabolismo , Transdução de Sinais
16.
Nat Commun ; 10(1): 2588, 2019 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-31197172

RESUMO

The brain is a genomic mosaic shaped by cellular responses to genome damage. Here, we manipulate somatic genome stability by conditional Knl1 deletion from embryonic mouse brain. KNL1 mutations cause microcephaly and KNL1 mediates the spindle assembly checkpoint, a safeguard against chromosome missegregation and aneuploidy. We find that following Knl1 deletion, segregation errors in mitotic neural progenitor cells give rise to DNA damage on the missegregated chromosomes. This triggers rapid p53 activation and robust apoptotic and microglial phagocytic responses that extensively eliminate cells with somatic genome damage, thus causing microcephaly. By leaving only karyotypically normal progenitors to continue dividing, these mechanisms provide a second safeguard against brain somatic aneuploidy. Without Knl1 or p53-dependent safeguards, genome-damaged cells are not cleared, alleviating microcephaly, but paradoxically leading to total pre-weaning lethality. Thus, mitotic genome damage activates robust responses to eliminate somatic mutant cells, which if left unpurged, can impact brain and organismal fitness.


Assuntos
Aneuploidia , Microcefalia/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Células-Tronco Neurais/fisiologia , Proteína Supressora de Tumor p53/metabolismo , Animais , Apoptose/genética , Segregação de Cromossomos/genética , Dano ao DNA/genética , Modelos Animais de Doenças , Embrião de Mamíferos , Instabilidade Genômica , Humanos , Cinetocoros/metabolismo , Camundongos , Camundongos Knockout , Proteínas Associadas aos Microtúbulos/genética , Cultura Primária de Células , Deleção de Sequência , Fuso Acromático/metabolismo
17.
Vet Microbiol ; 233: 39-46, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31176410

RESUMO

E5 protein, the major oncoprotein of bovine Deltapapillomavirus (BPV), was found to be expressed in 18 of 21 examined urothelial cancers of cattle. E5 oncoprotein was found to interact with p62 which was degraded through the autophagosome-lysosome pathway as well as LC3-II and appeared to be involved in the phosphorylation of the α-subunit of eukaryotic initiation factor 2 (eIF2α). Autophagy was morphologically documented by transmission electron microscope (TEM) through the detection of double-membrane autophagosomes and autolysosomes. Overexpression of Bag3 known to mediate selective autophagy was also demonstrated. Furthermore, Bag3 and BPV E5 oncoprotein were seen to co-localize with dynein and 14-3-3γ, which suggested that Bag3 could be involved in inducing the retrograde transport of BPV E5 along microtubules to aggresomes, perinuclear sites with high autophagic flux. Electron dense perinuclear structures consistent with aggresomes were also documented by TEM in urothelial cancer cells. Finally, Bag3 was found to also interact with synaptopodin 2 (Synpo2), which would seem to contribute to cargo degradation as it has been shown to facilitate autophagosome formation. This study provides mechanistic insights into the potential role(s) of autophagy in BPV disease, which can help to develop future treatment and control measures for BPV infection. Activation of autophagy correlates positively with BPV infection and may play a role in biological behavior of bladder cancer as urothelial carcinomas of cattle are known to be characterized by a relatively low rate of metastasis.


Assuntos
Autofagia , Papillomavirus Bovino 1/genética , Expressão Gênica , Proteínas Oncogênicas Virais/genética , Neoplasias da Bexiga Urinária/veterinária , Animais , Bovinos , Doenças dos Bovinos/virologia , DNA Viral/genética , DNA Viral/metabolismo , Fator de Iniciação 2 em Eucariotos/metabolismo , Feminino , Redes Reguladoras de Genes , Interações entre Hospedeiro e Microrganismos , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas Oncogênicas Virais/metabolismo , Fosforilação , Neoplasias da Bexiga Urinária/virologia , Urotélio/virologia
18.
Biochemistry (Mosc) ; 84(4): 358-369, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31228927

RESUMO

Cytoplasmic actin structures are essential components of the eukaryotic cytoskeleton. According to the classic concepts, actin structures perform contractile and motor functions, ensuring the possibility of cell shape changes during cell spreading, polarization, and movement both in vitro and in vivo, from the early embryogenesis stages and throughout the life of a multicellular organism. Intracellular organization of actin structures, their biochemical composition, and dynamic properties play a key role in the realization of specific cellular and tissue functions and vary in different cell types. This paper is a review of recent studies on the organization and properties of actin structures in endotheliocytes, interaction of these structures with other cytoskeletal components and elements involved in cell adhesion, as well as their role in the functional activity of endothelial cells.


Assuntos
Citoesqueleto de Actina/metabolismo , Actinas/metabolismo , Citoesqueleto de Actina/química , Actinas/química , Actinas/genética , Caderinas/química , Caderinas/metabolismo , Citosol/metabolismo , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Humanos , Proteínas Associadas aos Microtúbulos/metabolismo , Microtúbulos/química , Microtúbulos/metabolismo
19.
Eur J Histochem ; 63(2)2019 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-31189296

RESUMO

The Kölliker's organ is a transient epithelial structure during cochlea development that gradually degenerates and disappears at postnatal 12-14 days (P12-14). While apoptosis has been shown to play an essential role in the degeneration of the Kölliker's organ, the role of another programmed cell death, autophagy, remains unclear. In our study, autophagy markers including microtubule associated protein light chain 3-II (LC3-II), sequestosome 1 (SQSTM1/p62) and Beclin1 were detected in the supporting cells of the Kölliker's organ through immunohistochemistry staining. In addition, Western blot and real-time PCR revealed a gradually decreased expression of LC3-II and an increased expression of p62 during early postnatal development. Compared to apoptosis markers that peaks between P7 and P10, autophagy flux peaked earlier at P1 and decreased from P1 to P14. By transmission electron microscopy, we observed representative autophagosome and autolysosome that packaged various organelles in the supporting cells of the Kölliker's organ. During the degeneration, these organelles were digested via autophagy well ahead of the cellular apoptosis. These results suggest that autophagy plays an important role in transition and degeneration of the Kölliker's organ prior to apoptosis during the early postnatal development.


Assuntos
Apoptose/fisiologia , Autofagia/fisiologia , Cóclea/embriologia , Cóclea/metabolismo , Animais , Anticorpos/imunologia , Proteína Beclina-1/genética , Proteína Beclina-1/imunologia , Proteína Beclina-1/metabolismo , Caspase 3/genética , Caspase 3/imunologia , Caspase 3/metabolismo , Cóclea/citologia , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Imuno-Histoquímica/métodos , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/imunologia , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/imunologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , RNA Mensageiro/metabolismo , Ratos Sprague-Dawley , Proteína Sequestossoma-1/genética , Proteína Sequestossoma-1/imunologia , Proteína Sequestossoma-1/metabolismo , Fatores de Tempo
20.
Gene ; 712: 143935, 2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31247220

RESUMO

As seen in other types of cancer, development of drug resistance in NSCLC treatment causes adverse effects on disease fighting process. Recent studies have shown that one of the drug resistance development mechanisms is that cancer cells may acquire the ability to escape from cell death. Therefore, development of anticancer drugs which have the strategy to redirect cancer cells to any cell death pathways may provide positive results for cancer treatments. Autophagy may be a target mechanism of alternative cancer treatment strategy in cases of blocked apoptosis. There is also a complex molecular link between autophagy and apoptosis, has not been fully understood yet. The dicyano compound which we used in our study caused cell death in NSCLC cell lines. When we analyzed the cells which were treated with dicyano compound by transmission electron microscope, we observed autophagosome structures. Upon this result, we investigated expression levels of autophagic proteins in the dicyano compound-treated cells by immunoblotting and observed that expression levels of autophagic proteins were increased significantly. The TUNEL assay and qRT-PCR for pro-apoptotic and anti-apoptotic gene expression, which we performed to assess apoptosis in the dicyano compound-treated cells, showed that the cell death does not occur through apoptotic pathway. We showed that the dicyano compound, which was developed in our laboratories, may play a role in molecular link between apoptosis and autophagy and may shed light on development of new anticancer treatment strategies.


Assuntos
Autofagia , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Resistencia a Medicamentos Antineoplásicos , Galactose/química , Neoplasias Pulmonares/metabolismo , Triazóis/química , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Antineoplásicos , Apoptose , Proteínas Reguladoras de Apoptose/metabolismo , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cloroquina/química , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Concentração Inibidora 50 , Neoplasias Pulmonares/tratamento farmacológico , Microscopia Eletrônica de Transmissão , Proteínas Associadas aos Microtúbulos/metabolismo , Naftiridinas/metabolismo , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo
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