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1.
Brief Bioinform ; 25(3)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38602320

RESUMO

Breast cancer is a highly heterogeneous disease with varied subtypes, prognoses and therapeutic responsiveness. Human leukocyte antigen class I (HLA-I) shapes the immunity and thereby influences the outcome of breast cancer. However, the implications of HLA-I variations in breast cancer remain poorly understood. In this study, we established a multiomics cohort of 1156 Chinese breast cancer patients for HLA-I investigation. We calculated four important HLA-I indicators in each individual, including HLA-I expression level, somatic HLA-I loss of heterozygosity (LOH), HLA-I evolutionary divergence (HED) and peptide-binding promiscuity (Pr). Then, we evaluated their distribution and prognostic significance in breast cancer subtypes. We found that the four breast cancer subtypes had distinct features of HLA-I indicators. Increased expression of HLA-I and LOH were enriched in triple-negative breast cancer (TNBC), while Pr was relatively higher in hot tumors within TNBCs. In particular, a higher Pr indicated a better prognosis in TNBCs by regulating the infiltration of immune cells and the expression of immune molecules. Using the matched genomic and transcriptomic data, we found that mismatch repair deficiency-related mutational signature and pathways were enriched in low-Pr TNBCs, suggesting that targeting mismatch repair deficiency for synthetic lethality might be promising therapy for these patients. In conclusion, we presented an overview of HLA-I indicators in breast cancer and provided hints for precision treatment for low-Pr TNBCs.


Assuntos
Neoplasias Encefálicas , Neoplasias Colorretais , Antígenos de Histocompatibilidade Classe I , Síndromes Neoplásicas Hereditárias , Neoplasias de Mama Triplo Negativas , Humanos , Antígenos de Histocompatibilidade Classe I/genética , Neoplasias de Mama Triplo Negativas/metabolismo , Mutação , Perfilação da Expressão Gênica
2.
Kaohsiung J Med Sci ; 40(1): 74-85, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37850727

RESUMO

Brain damage in children due to seizures is irreversible and has been a major public health concern. The herbal monomer Xyloketal B (Xyl-B) can be used as a neuroprotective drug because of its antioxidant, antiapoptotic, and anti-inflammatory effects but with few adverse effects. In this article, we constructed a rat developmental convulsion model and a primary hippocampal neuronal cell convulsion model, through which we studied hippocampal neuronal morphology and neuronal apoptosis using H&E staining and TUNEL staining, respectively. Moreover, we measured TNF-α, IL-6, and IL-1ß inflammatory factor levels using ELISA, MDA, and SOD kits. The expression of SIRT3 in hippocampal tissues was determined by qPCR and Western blotting. The expression of autophagy-related proteins such as LC3, p62, and Beclin-1 was evaluated by Western blotting or immunohistochemistry. The role of SIRT3 and autophagic activity with Xyl-B in convulsive seizure-induced brain injury was investigated by knocking down SIRT3 expression levels. Our results showed that Xyl-B plays a neuroprotective role in convulsive seizure-induced brain injury by increasing SIRT3 expression and activating the autophagy pathway. The regulatory role of SIRT3 in the autophagy pathway with Xyl-B treatment was explored by knocking down SIRT3 expression and inhibiting autophagy. Our results revealed that SIRT3 enhances the protective effect of Xyl-B against postconvulsive brain injury by regulating AMPK/mTOR signaling-mediated autophagy.


Assuntos
Lesões Encefálicas , Piranos , Sirtuína 3 , Criança , Ratos , Animais , Humanos , Sirtuína 3/genética , Proteínas Quinases Ativadas por AMP/genética , Ratos Sprague-Dawley , Lesões Encefálicas/tratamento farmacológico , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Convulsões/tratamento farmacológico , Convulsões/genética , Autofagia , Apoptose
3.
J Stroke Cerebrovasc Dis ; 32(6): 107132, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37087770

RESUMO

BACKGROUND: Ischemic stroke is the obstruction of cerebral blood flow with a high morbidity. Microglial polarization is a contributing factor for ischemic stroke-induced injury. Here, we focused on function and mechanism of RNA binding protein RPS3 in microglial polarization after ischemic stroke. METHODS: Transient middle cerebral artery occlusion (tMCAO) was conducted in SD rats. Infarct area was detected by TTC staining and neurological score was assessed. Fluorescence staining tested neuronal apoptosis and microglial differentiation. Oxygen and glucose deprivation/reoxygenation (OGD/R) was applied for treating microglia. Levels of RPS3, SIRT1, M1 and M2 polarization markers (CD86, iNOS, CD206, Arg-1) were determined by RT-qPCR. Western blot detected RPS3, SIRT1, NLRP3, ASC and Cleaved-caspase-1 expression. RIP assay validated that RPS3 interacted with SIRT1. CCK-8 measured cell viability. Flow cytometry and ELISA assessed M1 and M2 polarization markers. LDH release was detected using colorimetric CytoTox 96 Cytotoxicity kit. RESULTS: RPS3 depletion improved neurological dysfunction and reduced infarction area in rats after tMCAO. Knockdown of RPS3 resulted in increased SIRT1 expression and decreased NLRP3 inflammasome activation, and induced microglia M2 polarization after ischemia-reperfusion (I/R). Besides, RPS3 directly targeted SIRT1 and reduced its expression in microglia. RPS3 silencing suppressed OGD/R-triggered neuronal and microglial cell death through SIRT1. Moreover, RPS3 activated NLRP3 inflammasome and regulated microglial polarization via SIRT1. CONCLUSION: RPS3 regulates microglial polarization and neuronal injury through SIRT1/NLRP3 pathway, suggesting a novel target for ischemic stroke treatment.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Animais , Ratos , Isquemia Encefálica/metabolismo , Glucose , Infarto da Artéria Cerebral Média/metabolismo , Inflamassomos/metabolismo , AVC Isquêmico/metabolismo , Microglia/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Ratos Sprague-Dawley , Sirtuína 1/genética , Sirtuína 1/metabolismo , Acidente Vascular Cerebral/metabolismo
4.
Signal Transduct Target Ther ; 8(1): 120, 2023 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-36959211

RESUMO

Loss of TGF-ß-mediated growth suppression is a major contributor to the development of cancers, best exemplified by loss-of-function mutations in genes encoding components of the TGF-ß signaling pathway in colorectal and pancreatic cancers. Alternatively, gain-of-function oncogene mutations can also disrupt antiproliferative TGF-ß signaling. However, the molecular mechanisms underlying oncogene-induced modulation of TGF-ß signaling have not been extensively investigated. Here, we show that the oncogenic BCR-ABL1 of chronic myelogenous leukemia (CML) and the cellular ABL1 tyrosine kinases phosphorylate and inactivate Smad4 to block antiproliferative TGF-ß signaling. Mechanistically, phosphorylation of Smad4 at Tyr195, Tyr301, and Tyr322 in the linker region interferes with its binding to the transcription co-activator p300/CBP, thereby blocking the ability of Smad4 to activate the expression of cyclin-dependent kinase (CDK) inhibitors and induce cell cycle arrest. In contrast, the inhibition of BCR-ABL1 kinase with Imatinib prevented Smad4 tyrosine phosphorylation and re-sensitized CML cells to TGF-ß-induced antiproliferative and pro-apoptotic responses. Furthermore, expression of phosphorylation-site-mutated Y195F/Y301F/Y322F mutant of Smad4 in Smad4-null CML cells enhanced antiproliferative responses to TGF-ß, whereas the phosphorylation-mimicking Y195E/Y301E/Y322E mutant interfered with TGF-ß signaling and enhanced the in vivo growth of CML cells. These findings demonstrate the direct role of BCR-ABL1 tyrosine kinase in suppressing TGF-ß signaling in CML and explain how Imatinib-targeted therapy restored beneficial TGF-ß anti-growth responses.


Assuntos
Leucemia Mielogênica Crônica BCR-ABL Positiva , Humanos , Mesilato de Imatinib/farmacologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Fosforilação , Proteína Smad4/genética , Proteína Smad4/metabolismo , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo , Tirosina/metabolismo
5.
Proc Natl Acad Sci U S A ; 119(46): e2207201119, 2022 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-36343244

RESUMO

The transcription variation, leading to various forms of transcripts and protein diversity, remains largely unexplored in triple-negative breast cancers (TNBCs). Here, we presented a comprehensive analysis of RNA splicing in breast cancer to illustrate the biological function and clinical implications of tumor-specific transcripts (TSTs) arising from these splicing junctions. Aberrant RNA splicing or TSTs were frequently harbored in TNBC and were correlated with a poor outcome. We discovered a tumor-specific splicing variant of macrophage receptor with collagenous structure-TST (MARCO-TST), which was distinguished from myeloid cell-specific wild-type MARCO. MARCO-TST expression was associated with poor outcomes in TNBC patients and could promote tumor progression in vitro and in vivo. Mechanically, MARCO-TST interacted with PLOD2 and enhanced the stability of HIF-1α, which resulted in the metabolic dysregulation of TNBC to form a hypoxic tumor microenvironment. MARCO-TST was initiated from a de novo alternative transcription initiation site that was activated by a superenhancer. Tumors with MARCO-TST expression conferred greater sensitivity to bromodomain and extraterminal protein inhibitors. This treatment strategy was further validated in patient-derived organoids. In conclusion, our results revealed the transcription variation landscape of TNBC, highlighting MARCO-TST as a crucial oncogenic transcript and therapeutic target.


Assuntos
Neoplasias de Mama Triplo Negativas , Humanos , Neoplasias de Mama Triplo Negativas/metabolismo , Regulação Neoplásica da Expressão Gênica , Linhagem Celular Tumoral , Carcinogênese/genética , Splicing de RNA , Proliferação de Células , Microambiente Tumoral
6.
Comput Math Methods Med ; 2022: 3665841, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36035290

RESUMO

This study was aimed to explore the efficacy of ultrasound with active contour model (ACM) for hemodialysis in children with renal failure. The pulse coupled neural network (PCNN) was used to extract the initial contour of the ultrasound images, and the cloud model-based ACM was used to accurately segment the images, whose effect was compared with the classic Snake model. 84 children with chronic renal failure who received hemodialysis treatment in hospital were selected as research objects. There were 42 cases in the control group who were diagnosed by conventional ultrasound and 42 cases in the observation group who were diagnosed by ultrasound with the algorithm. Then, 42 children who underwent healthy physical examination (health group) were selected for comparison of related analysis indicators. The error rates of different algorithms were compared to analyze the levels of inflammatory factors in different groups of patients after hemodialysis. The results showed that the error rate of classical Snake model was 18.87% and that of ACM algorithm model was 11.01%, and the error rate of ACM algorithm model was significantly lower (P < 0.05). After hemodialysis, the level of tumor necrosis factor (TNF)-α was 38.76 pg/mL in the observation group and 40.05 pg/mL in the control group, which was notably decreased in both groups, especially in the observation group (P < 0.05). After hemodialysis, transforming growth factor (TGF)-ß1 was 7.76 ng/mL in the observation group and 7.60 ng/mL in the control group, which was significantly reduced in both groups. After treatment, UA and Scr in both groups were significantly reduced, and the reduction was more significant in the observation group (P < 0.05). HGB and RBC were significantly increased in both groups, and the increase was more significant in the observation group (P < 0.05). In summary, ACM algorithm had a good segmentation effect on the ultrasonic images of children with renal failure. This study provided guidance for clinicians to choose the algorithm for the application of ultrasonic imaging diagnosis.


Assuntos
Falência Renal Crônica , Diálise Renal , Algoritmos , Criança , Humanos , Ultrassonografia
7.
Front Psychol ; 13: 817529, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35250750

RESUMO

Several recent studies have found that when the other's gain is greater, even subjects' reward may seem like a loss and lead to a negative experience. These studies indicate the complexity of reward evaluation in the context of social comparison. The satisfaction rating of reward outcome not only depends on objective social comparison but also on subjective evaluation. However, less is known about the neural time course of subjective evaluation. Therefore, we employed a 2 (subjective evaluation: advantageous vs. disadvantageous) × 2 (comparison direction: upward vs. downward) within-subjects factorial design, in which we manipulated the reward distribution for the subjects. Electroencephalography (EEG) responses were recorded, while two subjects concurrently but independently performed a simple dot-estimation task that entailed monetary rewards. Behavioral results showed that the subjects were more satisfied with the advantageous distribution, regardless of upward or downward comparison. The analysis of event-related potentials (ERPs) revealed that disadvantageous distribution elicited a larger P2 than advantageous distribution, and this effect was not modulated by comparison direction. In contrast, the late positive potential (LPP) showed an effect of comparison direction independent of subjective evaluation. The data suggest that subjective evaluation acts upon the early stage of reward processing and manifests in the P2 component, whereas social comparison plays a role in the later appraisal process.

8.
Eur J Pharmacol ; 912: 174620, 2021 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-34752743

RESUMO

BACKGROUND: Epilepsy is a common chronic neurological disease. Recurrent seizures can cause irreversible brain damage. This study aimed to explore the regulation of Genistein on JAK2/STAT3 and Keap1/Nrf2 signaling pathway and the protective effects on brain injury after epilepsy. METHODS: Pentylenetetrazole (PTZ) was used to induce epilepsy in developing rats and Genistein was used for pretreatment of epilepsy. The seizure latency, grade scores and duration of the first generalized tonic-clonic seizure (GTCs) were recorded. Hippocampus tissue was sampled at 24 h post-epilepsy. Immunofluorescence staining was used to observe mature neurons, activated microglia and astrocytes in the hippocampal CA1 region. Western blot and qRT-PCR were used to determine the protein and mRNA levels of JAK2, STAT3, TNF-α, IL-1ß, Keap1, Nrf2, HO-1, NQO1, caspase3, Bax and Bcl2 in the hippocampus. RESULTS: Immunofluorescence showed that the number of neurons significantly decreased, and activated microglia and astrocytes significantly increased after epilepsy; Western blot and q-PCR showed that the expressions of JAK2, STAT3, TNF-α, IL-1ß, Keap1, caspase3 and Bax significantly increased, while Nrf2, HO-1, NQO1 and Bcl-2 were significantly reduced after epilepsy. These effects were reversed by Genistein treatment. Moreover, Genistein was found to prolong seizure latency and reduce seizure intensity score and duration of generalized tonic-clonic seizures(GTCs) CONCLUSIONS: Genistein can activate the Keap1/Nrf2 antioxidant stress pathway and attenuate the activation of microglia and astrocytes. Genistein also inhibits the JAK2-STAT3 inflammation pathway and expression of apoptotic proteins, and increases the number of surviving neurons, thus having a protective effect on epilepsy-induced brain damage.


Assuntos
Lesões Encefálicas/prevenção & controle , Genisteína/farmacologia , Janus Quinase 2/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Fármacos Neuroprotetores/farmacologia , Fator de Transcrição STAT3/metabolismo , Animais , Apoptose/efeitos dos fármacos , Astrócitos/efeitos dos fármacos , Lesões Encefálicas/etiologia , Lesões Encefálicas/metabolismo , Lesões Encefálicas/patologia , Caspase 3/genética , Caspase 3/metabolismo , Modelos Animais de Doenças , Epilepsia/complicações , Epilepsia/metabolismo , Epilepsia/patologia , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Janus Quinase 2/antagonistas & inibidores , Proteína 1 Associada a ECH Semelhante a Kelch/antagonistas & inibidores , Proteína 1 Associada a ECH Semelhante a Kelch/genética , Masculino , Microglia/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/antagonistas & inibidores , Fator 2 Relacionado a NF-E2/genética , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos Sprague-Dawley , Fator de Transcrição STAT3/antagonistas & inibidores , Fator de Transcrição STAT3/genética , Transdução de Sinais/efeitos dos fármacos , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo
9.
Br J Cancer ; 124(12): 1912-1920, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33758331

RESUMO

The bone marrow has been widely recognised to host a unique microenvironment that facilitates tumour colonisation. Bone metastasis frequently occurs in the late stages of malignant diseases such as breast, prostate and lung cancers. The biology of bone metastasis is determined by tumour-cell-intrinsic traits as well as their interaction with the microenvironment. The bone marrow is a dynamic organ in which various stages of haematopoiesis, osteogenesis, osteolysis and different kinds of immune response are precisely regulated. These different cellular components constitute specialised tissue microenvironments-niches-that play critical roles in controlling tumour cell colonisation, including initial seeding, dormancy and outgrowth. In this review, we will dissect the dynamic nature of the interactions between tumour cells and bone niches. By targeting certain steps of tumour progression and crosstalk with the bone niches, the development of potential therapeutic approaches for the clinical treatment of bone metastasis might be feasible.


Assuntos
Medula Óssea/patologia , Neoplasias Ósseas/secundário , Células-Tronco Neoplásicas/fisiologia , Nicho de Células-Tronco/fisiologia , Animais , Neoplasias Ósseas/patologia , Neoplasias da Mama/patologia , Feminino , Humanos , Neoplasias Pulmonares/patologia , Masculino , Osteogênese/fisiologia , Neoplasias da Próstata/patologia , Microambiente Tumoral/fisiologia
11.
Contemp Nurse ; 55(1): 59-70, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30830839

RESUMO

Background: Ensuring the delivery of quality care and patient safety requires that nurses improve their self-reflection and insight as well as their critical thinking. To understand the factors that influence self-reflection, insight, and critical thinking, more evidence-based research is needed. Purpose: The purpose of this study was to examine whether professional qualifications (i.e. age, years of job experience, and position on the clinical ladder) would affect self-reflection and critical thinking in the experienced registered nurses (RNs) group. Methods: This quantitative and correlational study included 597 RNs (297 novice nurses and 300 experienced nurses), recruited from one medical center hospital in central Taiwan, as participants. Data were collected on self-reflection and critical thinking, using the Chinese-version of the Self-Reflection and Insight Scale and the Taiwan Critical Thinking Disposition Inventory. A structural equation modeling approach was used to examine the relationships among variables. Findings: The results showed a non-significant mean difference in self-reflection with insight scores between the two groups. Experienced RNs had a significantly higher mean score for critical thinking. Further analysis of the data of experienced nurses revealed that self-reflection with insight significantly affected critical thinking (ß = 0.24, t = 4.141, p < .001). Qualifications also affected self-reflection with insight (ß = 0.11, t = 1.808, p > .05) and critical thinking (ß = 0.18, t = 3.143, p < .001). The correlation between qualifications and self-reflection with insight, however, was non-significant. Discussion: Nurses who perceived that they had greater self-reflection and insight reported more critical thinking in clinical care practice. Nurses' qualifications had more of an effect on critical thinking than on self-reflection and insight.


Assuntos
Competência Clínica , Recursos Humanos de Enfermagem/psicologia , Autoavaliação (Psicologia) , Adulto , Feminino , Humanos , Masculino , Taiwan , Pensamento
12.
Nat Cell Biol ; 21(2): 179-189, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30664791

RESUMO

Loss of TGF-ß tumour suppressive response is a hallmark of human cancers. As a central player in TGF-ß signal transduction, SMAD4 (also known as DPC4) is frequently mutated or deleted in gastrointestinal and pancreatic cancer. However, such genetic alterations are rare in most cancer types and the underlying mechanism for TGF-ß resistance is not understood. Here we describe a mechanism of TGF-ß resistance in ALK-positive tumours, including lymphoma, lung cancer and neuroblastoma. We demonstrate that, in ALK-positive tumours, ALK directly phosphorylates SMAD4 at Tyr 95. Phosphorylated SMAD4 is unable to bind to DNA and fails to elicit TGF-ß gene responses and tumour suppressing responses. Chemical or genetic interference of the oncogenic ALK restores TGF-ß responses in ALK-positive tumour cells. These findings reveal that SMAD4 is tyrosine-phosphorylated by an oncogenic tyrosine kinase during tumorigenesis. This suggests a mechanism by which SMAD4 is inactivated in cancers and provides guidance for targeted therapies in ALK-positive cancers.


Assuntos
Quinase do Linfoma Anaplásico/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Neoplasias/genética , Proteína Smad4/genética , Fator de Crescimento Transformador beta/farmacologia , Quinase do Linfoma Anaplásico/metabolismo , Animais , Linhagem Celular , Linhagem Celular Tumoral , Perfilação da Expressão Gênica/métodos , Células HEK293 , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias/metabolismo , Neoplasias/patologia , Fosforilação , Proteína Smad4/metabolismo , Transplante Heterólogo , Tirosina/genética , Tirosina/metabolismo
13.
Cancer Res ; 78(21): 6073-6085, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30171053

RESUMO

TGFß signaling inhibits cell proliferation to block cancer initiation, yet it also enhances metastasis to promote malignancy during breast cancer development. The mechanisms underlying these differential effects are still unclear. Here, we report that HER2/EGFR signaling switches TGFß function in breast cancer cells from antiproliferation to cancer promotion. Inhibition of HER2/EGFR activity attenuated TGFß-induced epithelial-mesenchymal transition and migration but enhanced the antiproliferative activity of TGFß. Activation of HER2/EGFR induced phosphorylation of Smad3 at Ser208 of the linker region through AKT, which promoted the nuclear accumulation of Smad3 and subsequent expression of the genes related to EMT and cell migration. In contrast, HER2/EGFR signaling had no effects on the nuclear localization of Smad2. Knockdown of Smad3, but not Smad2, blocked TGFß-induced breast cancer cell migration. We observed a positive correlation between the nuclear localization of Smad3 and HER2 activation in advanced human breast cancers. Our results demonstrate a key role for HER2/EGFR in differential regulation of Smad3 activity to shift TGFß function from antitumorigenic to protumorigenic during breast cancer development.Significance: TGFß signaling can shift from inhibiting to promoting breast cancer development via HER2/EGFR AKT-mediated phosphorylation of Smad3 at S208, enhancing its nuclear accumulation and upregulation of EMT-related genes.Graphical Abstract: http://cancerres.aacrjournals.org/content/canres/78/21/6073/F1.large.jpg Cancer Res; 78(21); 6073-85. ©2018 AACR.


Assuntos
Neoplasias da Mama/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor ErbB-2/metabolismo , Transdução de Sinais , Fator de Crescimento Transformador beta1/metabolismo , Adulto , Idoso , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Transição Epitelial-Mesenquimal/genética , Receptores ErbB/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Células HEK293 , Humanos , Neoplasias Pulmonares/metabolismo , Pessoa de Meia-Idade , Metástase Neoplásica , Fosforilação , Regulação para Cima
14.
Open Biol ; 8(4)2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29618518

RESUMO

The epithelial-to-mesenchymal transition (EMT) is a cellular reprogramming process converting epithelial cells into mesenchymal cell morphology. Snail is a critical regulator of EMT by both suppressing epithelial gene expression and promoting mesenchymal gene expression. Expression and activity of Snail are tightly controlled at transcriptional and post-translational levels. It has previously been reported that Snail undergoes phosphorylation and ubiquitin-dependent proteasome degradation. Here, we report nuclear phosphatase SCP4/CTDSPL2 acts as a novel Snail phosphatase. SCP4 physically interacts with and directly dephosphorylates Snail. SCP4-mediated dephosphorylation of Snail suppresses the ubiquitin-dependent proteasome degradation of Snail and consequently enhances TGFß-induced EMT. The knockdown of SCP4 in MCF10A mammary epithelial cells leads to attenuated cell migration. Collectively, our finding demonstrates that SCP4 plays a critical role in EMT through Snail dephosphorylation and stabilization.


Assuntos
Transição Epitelial-Mesenquimal/genética , Fosfoproteínas Fosfatases/fisiologia , Fatores de Transcrição da Família Snail/metabolismo , Linhagem Celular , Movimento Celular/genética , Técnicas de Silenciamento de Genes , Células HEK293 , Humanos , Fosfoproteínas Fosfatases/genética , Fosfoproteínas Fosfatases/metabolismo , Fosforilação , Fatores de Transcrição da Família Snail/fisiologia
15.
Proc Natl Acad Sci U S A ; 114(38): 10113-10118, 2017 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-28874583

RESUMO

Smad7 is a negative feedback product of TGF-ß superfamily signaling and fine tunes a plethora of pleiotropic responses induced by TGF-ß ligands. However, its noncanonical functions independent of TGF-ß signaling remain to be elucidated. Here, we show that Smad7 activates signal transducers and activators of transcription 3 (STAT3) signaling in maintaining mouse embryonic stem cell pluripotency in a manner independent of the TGF-ß receptors, yet dependent on the leukemia inhibitory factor (LIF) coreceptor glycoprotein 130 (gp130). Smad7 directly binds to the intracellular domain of gp130 and disrupts the SHP2-gp130 or SOCS3-gp130 complex, thereby amplifying STAT3 activation. Consequently, Smad7 facilitates LIF-mediated self-renewal of mouse ESCs and is also critical for induced pluripotent stem cell reprogramming. This finding illustrates an uncovered role of the Smad7-STAT3 interplay in maintaining cell pluripotency and also implicates a mechanism involving Smad7 underlying cytokine-dependent regulation of cancer and inflammation.


Assuntos
Células-Tronco Embrionárias Murinas/metabolismo , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Proteína Smad7/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Animais , Receptor gp130 de Citocina/genética , Receptor gp130 de Citocina/metabolismo , Células HEK293 , Humanos , Camundongos , Células-Tronco Embrionárias Murinas/citologia , Proteína Tirosina Fosfatase não Receptora Tipo 11/genética , Proteína Tirosina Fosfatase não Receptora Tipo 11/metabolismo , Fator de Transcrição STAT3/genética , Proteína Smad7/genética , Fator de Crescimento Transformador beta/genética
17.
Mitochondrial DNA B Resour ; 2(2): 526-527, 2017 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-33473885

RESUMO

Gymnodraco acuticepsis is an Antarctic fish living in the Southern Ocean. Until now, studies on G. acuticeps are still limited. As an Antarctic fish, obtaining and characterization of the mitochondrial genome of G. acuticeps will be important for elucidation of the mechanism of cold-adapting evolution in mitochondrion. In this study, we first isolated and characterized the mitochondrial genome sequence of G. acuticeps with 15,987 bp in length. It contained of 34 genes (12 protein-coding genes, 20 transfer RNA genes, 2 ribosomal RNA genes) and a partial putative control region. Gene organization and nucleotide composition of obtained mito-genome were similar to those of other Antarctic fish. Twenty-eight genes were encoded by heavy strand, while six genes were encoded by light strand. Further, the phylogenetic tree, which based on 12 protein-coding genes, revealed that the G. acuticeps was genetically closest to species Parachaenichthys charcoti among 18 species. We hope this work would be helpful for the population genetics and molecular evolution studies.

18.
Mitochondrial DNA A DNA Mapp Seq Anal ; 27(5): 3820-1, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27158874

RESUMO

In the present study, we obtained the complete mitochondrial genome sequence of Eleotris oxycephala, which was 16 527 bp in length. This genome consisted of 13 protein-coding genes, 22 transfer RNA genes, two ribosomal RNA genes and a putative control region. Of the 37 genes, 28 were encoded by heavy strand, while nine were encoded by light strand. The overall base composition of this mitogenome was 28.21% for A, 16.81% for G, 24.75% for T, 30.23% for C, respectively, with a slight higher A + T content (52.96%). The phylogenetic analysis based on 13 concatenated protein-coding genes suggested that E. oxycephala as a sister species to Eleotris acanthopoma was clustered in family Eleotridae. This complete mitochondrial genome sequence of E. oxycephala should be helpful for the studies on population genetic structure, molecular evolution and phylogeny of E. oxycephala and related species.


Assuntos
Genoma Mitocondrial , Perciformes/genética , Animais , Composição de Bases , Sequência de Bases , Sequência Conservada , DNA Mitocondrial/genética , Evolução Molecular , Ordem dos Genes , Genes de RNAr , Filogenia , RNA de Transferência/genética , Sequenciamento Completo do Genoma
19.
J Biol Chem ; 291(10): 5396-405, 2016 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-26763233

RESUMO

The epithelial-to-mesenchymal transition (EMT) is a process by which differentiated epithelial cells reprogram gene expression, lose their junctions and polarity, reorganize their cytoskeleton, increase cell motility and assume a mesenchymal morphology. Despite the critical functions of the microtubule (MT) in cytoskeletal organization, how it participates in EMT induction and maintenance remains poorly understood. Here we report that acetylated α-tubulin, which plays an important role in microtubule (MT) stabilization and cell morphology, can serve as a novel regulator and marker of EMT. A high level of acetylated α-tubulin was correlated with epithelial morphology and it profoundly decreased during TGF-ß-induced EMT. We found that TGF-ß increased the activity of HDAC6, a major deacetylase of α-tubulin, without affecting its expression levels. Treatment with HDAC6 inhibitor tubacin or TGF-ß type I receptor inhibitor SB431542 restored the level of acetylated α-tubulin and consequently blocked EMT. Our results demonstrate that acetylated α-tubulin can serve as a marker of EMT and that HDAC6 represents an important regulator during EMT process.


Assuntos
Transição Epitelial-Mesenquimal , Histona Desacetilases/metabolismo , Processamento de Proteína Pós-Traducional , Tubulina (Proteína)/metabolismo , Acetilação , Anilidas/farmacologia , Animais , Benzamidas/farmacologia , Dioxóis/farmacologia , Células HEK293 , Desacetilase 6 de Histona , Histona Desacetilases/genética , Humanos , Ácidos Hidroxâmicos/farmacologia , Células MCF-7 , Camundongos , Microtúbulos/metabolismo , Fator de Crescimento Transformador beta/farmacologia
20.
Mitochondrial DNA A DNA Mapp Seq Anal ; 27(6): 4296-4297, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-26404517

RESUMO

In this study, we reported the complete mitochondrial DNA sequence of Cubiceps squamiceps, and its phylogenetic relationship. The full length of this mitogenome was 16 510 bp, including 22 transfer RNA genes, two ribosomal RNA genes, 13 protein-coding genes, and a putative control region. The location of genes in mitochondrial genome was similar to other fish species within family Nomeidae. Twenty-eight genes were located on the heavy strand, while nine genes were located on the light strand. The nucleotide composition of this mitogenome was 27.5% for A, 28.5% for C, 17.5% for G, and 26.5% for T. From the NJ phylogenetic tree, we can find that C. squamiceps was genetically closest to C. pauciradiatus among 20 species within suborder Stromateoidei. This study could lay the basis for the future studies in population genetic diversity, taxonomic status, molecular systematics, and conservation genetics in C. squamiceps.


Assuntos
DNA Mitocondrial/genética , Genoma Mitocondrial/genética , Perciformes/genética , Animais , Composição de Bases/genética , Sequência de Bases/genética , Sequência Conservada/genética , Peixes/genética , Ordem dos Genes/genética , Genes Mitocondriais/genética , Mitocôndrias/genética , Filogenia , Análise de Sequência de DNA/métodos
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