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1.
J Bone Oncol ; 45: 100593, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38495379

RESUMO

Background and objective: Pelvic bone tumors represent a harmful orthopedic condition, encompassing both benign and malignant forms. Addressing the issue of limited accuracy in current machine learning algorithms for bone tumor image segmentation, we have developed an enhanced bone tumor image segmentation algorithm. This algorithm is built upon an improved full convolutional neural network, incorporating both the fully convolutional neural network (FCNN-4s) and a conditional random field (CRF) to achieve more precise segmentation. Methodology: The enhanced fully convolutional neural network (FCNN-4s) was employed to conduct initial segmentation on preprocessed images. Following each convolutional layer, batch normalization layers were introduced to expedite network training convergence and enhance the accuracy of the trained model. Subsequently, a fully connected conditional random field (CRF) was integrated to fine-tune the segmentation results, refining the boundaries of pelvic bone tumors and achieving high-quality segmentation. Results: The experimental outcomes demonstrate a significant enhancement in segmentation accuracy and stability when compared to the conventional convolutional neural network bone tumor image segmentation algorithm. The algorithm achieves an average Dice coefficient of 93.31 %, indicating superior performance in real-time operations. Conclusion: In contrast to the conventional convolutional neural network segmentation algorithm, the algorithm presented in this paper boasts a more intricate structure, proficiently addressing issues of over-segmentation and under-segmentation in pelvic bone tumor segmentation. This segmentation model exhibits superior real-time performance, robust stability, and is capable of achieving heightened segmentation accuracy.

2.
Front Biosci (Elite Ed) ; 16(1): 6, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38538524

RESUMO

BACKGROUND: This research explores the significance of miR-215-5p and vasculogenic mimicry (VM) in forecasting the prognosis for hepatocellular carcinoma (HCC). METHODS: We analyzed HCC-associated miRNA expression profiles using data from The Cancer Genome Atlas (TCGA) and the Gene Expression Omnibus (GEO). Samples included tissue and blood from 80 early-stage HCC patients and serum from 120 healthy individuals. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was employed to measure miR-215-5p and zinc finger E-box binding homeobox 2 (ZEB2) gene expressions. Hematoxylin and eosin (H&E) and CD34/Periodic Acid-Schiff (PAS) double staining assessed VM presence in HCC tissue sections. Bioinformatics tools predicted interactions between miR-215-5p and ZEB2, confirmed through luciferase reporter assays. We also examined the impact of miR-215-5p or ZEB2 overexpression on HCC cell invasion, migration, and VM formation using scratch, Transwell invasion assays, and Matrigel 3D cultures. RESULTS: Bioinformatics analysis indicated that miR-215-5p was under-expressed in HCC, particularly in cases with vascular invasion, which correlated with worse patient outcomes. In contrast, ZEB2, targeted by miR-215-5p, was overexpressed in HCC. RT-qPCR validated these expression patterns in HCC tissues. Among the HCC patients, 38 were VM positive and 42 VM negative. Logistic regression highlighted a negative correlation between miR-215-5p levels and VM positivity in HCC tissues and a positive correlation for ZEB2 with VM positivity and tumor vascular invasion. Lower miR-215-5p levels were linked to increased HCC recurrence and metastasis. Both bioinformatics analysis and luciferase assays demonstrated a direct interaction between miR-215-5p and ZEB2. Enhancing miR-215-5p levels reduced ZEB2 expression, consequently diminishing invasion, migration, and VM formation of the HCC cells in vitro. CONCLUSIONS: miR-215-5p expression inversely correlates with VM occurrence in HCC tissues, while ZEB2 expression shows a direct correlation. By targeting ZEB2, miR-215-5p may hinder VM in HCC tissues, helping to prevent vascular invasion and HCC recurrence. Thus, miR-215-5p emerges as a vital prognostic indicator for predicting vascular invasion and recurrence in HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , MicroRNAs , Humanos , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Linhagem Celular Tumoral , Luciferases/genética , Luciferases/metabolismo , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Movimento Celular/genética
3.
J Biochem Mol Toxicol ; 38(1): e23601, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38069819

RESUMO

Dysregulation of osteoblastic differentiation is an important risk factor of osteoporosis, the therapy of which is challenging. Dehydrocostus lactone (DHC), a sesquiterpene isolated from medicinal plants, has displayed anti-inflammatory and antitumor properties. In this study, we investigated the effects of DHC on osteoblastic differentiation and mineralization of MC3T3-E1 cells. Interestingly, we found that DHC increased the expression of marker genes of osteoblastic differentiation, such as alkaline phosphatase (ALP), osteocalcin (OCN), and osteopontin (OPN). Additionally, DHC increased the expressions of collagen type I alpha 1 (Col1a1) and collagen type I alpha 2 (Col1a2). We also demonstrate that DHC increased ALP activity. Importantly, the Alizarin Red S staining assay revealed that DHC enhanced osteoblastic differentiation of MC3T3-E1 cells. Mechanistically, it is shown that DHC increased the expression of Runx-2, a central regulator of osteoblastic differentiation. Treatment with DHC also increased the levels of phosphorylated p38, and its blockage using its specific inhibitor SB203580 abolished the effects of DHC on runt-related transcription factor 2 (Runx-2) expression and osteoblastic differentiation, suggesting the involvement of p38. Based on these findings, we concluded that DHC might possess a capacity for the treatment of osteoporosis by promoting osteoblastic differentiation.


Assuntos
Colágeno Tipo I , Lactonas , Osteoporose , Sesquiterpenos , Humanos , Colágeno Tipo I/metabolismo , Transdução de Sinais , Diferenciação Celular , Fosfatase Alcalina/metabolismo , Osteogênese
4.
Biomedicines ; 11(12)2023 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-38137428

RESUMO

Na/K-ATPase (NKA)-mediated regulation of Src kinase, which involves defined amino acid sequences of the NKA α1 polypeptide, has emerged as a novel regulatory mechanism of mitochondrial function in metazoans. Mitochondrial metabolism ensures adequate myocardial performance and adaptation to physiological demand. It is also a critical cellular determinant of cardiac repair and remodeling. To assess the impact of the proposed NKA/Src regulatory axis on cardiac mitochondrial metabolic function, we used a gene targeting approach in human cardiac myocytes. Human induced pluripotent stem cells (hiPSC) expressing an Src-signaling null mutant (A420P) form of the NKA α1 polypeptide were generated using CRISPR/Cas9-mediated genome editing. Total cellular Na/K-ATPase activity remained unchanged in A420P compared to the wild type (WT) hiPSC, but baseline phosphorylation levels of Src and ERK1/2 were drastically reduced. Both WT and A420P mutant hiPSC readily differentiated into cardiac myocytes (iCM), as evidenced by marker gene expression, spontaneous cell contraction, and subcellular striations. Total NKA α1-3 protein expression was comparable in WT and A420P iCM. However, live cell metabolism assessed functionally by Seahorse extracellular flux analysis revealed significant reductions in both basal and maximal rates of mitochondrial respiration, spare respiratory capacity, ATP production, and coupling efficiency. A significant reduction in ROS production was detected by fluorescence imaging in live cells, and confirmed by decreased cellular protein carbonylation levels in A420P iCM. Taken together, these data provide genetic evidence for a role of NKA α1/Src in the tonic stimulation of basal mitochondrial metabolism and ROS production in human cardiac myocytes. This signaling axis in cardiac myocytes may provide a new approach to counteract mitochondrial dysfunction in cardiometabolic diseases.

5.
J Bone Oncol ; 42: 100502, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37736418

RESUMO

Background and objective: Bone tumor is a kind of harmful orthopedic disease, there are benign and malignant points. Aiming at the problem that the accuracy of the existing machine learning algorithm for bone tumor image segmentation is not high, a bone tumor image segmentation algorithm based on improved full convolutional neural network which consists fully convolutional neural network (FCNN-4s) and conditional random field (CRF). Methodology: The improved fully convolutional neural network (FCNN-4s) was used to perform coarse segmentation on preprocessed images. Batch normalization layers were added after each convolutional layer to accelerate the convergence speed of network training and improve the accuracy of the trained model. Then, a fully connected conditional random field (CRF) was fused to refine the bone tumor boundary in the coarse segmentation results, achieving the fine segmentation effect. Results: The experimental results show that compared with the traditional convolutional neural network bone tumor image segmentation algorithm, the algorithm has a great improvement in segmentation accuracy and stability, the average Dice can reach 91.56%, the real-time performance is better. Conclusion: Compared with the traditional convolutional neural network segmentation algorithm, the algorithm in this paper has a more refined structure, which can effectively solve the problem of over-segmentation and under-segmentation of bone tumors. The segmentation prediction has better real-time performance, strong stability, and can achieve higher segmentation accuracy.

6.
Bioengineered ; 13(5): 13680-13688, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35706414

RESUMO

Long non-coding RNA (lncRNA) plasmacytoma variant translocation 1 (PVT1) and growth arrest specific 5 (GAS5) have opposite functions in the apoptosis of chondrocytes, which are involved in the pathogenesis of osteoarthritis (OA). The opposite roles of PVT1 and GAS5 in OA may indicate the existence of crosstalk between them in OA. This study aimed to explore the possible interaction between PVT1 and GAS5 in OA. Accumulation of PVT1 and GAS5 in OA and control synovial fluid samples was measured by RT-qPCR. The interaction between PVT1 and GAS5 in chondrocytes was explored by overexpression experiments. Dual-luciferase reporter assay was performed to analyze the binding of PVT1 and GAS5 to each other's promoter regions. Regulatory roles of PVT1 and GAS5 in the apoptosis of chondrocytes were studied with cell apoptosis assay. PVT1 was upregulated in OA, and GAS5 was downregulated in OA. An inverse correlation between PVT1 and GAS5 was observed across OA samples. Under lipopolysaccharides (LPS) treatment, PVT1 was upregulated and GAS5 was downregulated. Interestingly, PVT1 and GAS5 overexpression downregulated each other in chondrocytes. Cell apoptosis analysis showed that PVT1 overexpression promoted cell apoptosis, while GAS5 overexpression suppressed cell apoptosis induced by LPS. Co-transfection of PVT1 and GAS5 failed to significantly affect cell apoptosis. PVT1 and GAS5 directly bound to each other's promoter regions. Our study characterized the interaction between PVT1 and GAS5 in OA. Their interaction regulated the apoptosis of chondrocytes, which play a critical role in OA. PVT1 and GAS5 may form a negative feedback loop in OA.


Assuntos
MicroRNAs , Osteoartrite , Plasmocitoma , RNA Longo não Codificante , Apoptose/genética , Condrócitos/metabolismo , Humanos , Lipopolissacarídeos/metabolismo , MicroRNAs/metabolismo , Osteoartrite/genética , Osteoartrite/metabolismo , Plasmocitoma/complicações , Plasmocitoma/metabolismo , Plasmocitoma/patologia , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo
7.
BMC Musculoskelet Disord ; 23(1): 340, 2022 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-35397519

RESUMO

BACKGROUND: Macrophages are one of the important cells in immune system. In this article, we aim to explore the regulatory role of miR-455-3p on proliferation and osteoblast differentiation of RAW264.7 cells. METHODS: Expression levels of genes and proteins in cells were tested via qRT-PCR and western blot. The targeted correlation between miR-455-3p and PTEN was identified by luciferase analysis. MTT assay and flow cytometry were applied to detect the proliferation and apoptosis of cells. Osteoclastogenesis was completed by stimulating RAW 264.7 cells with RANKL. Tartrate-resistant acid phosphatase (TRAP) activity in different groups of cells were assessed. RESULTS: Firstly, we determined that up-regulation of miR-455-3p promoted the proliferation and inhibited apoptosis of RAW 264.7 cells. MiR-455-3p deficiency played opposite effect in RAW 264.7 cells. Additionally, osteoclastogenesis-related factors (TRAP, CTSK and NFATc1) expression levels were remarkably up-regulated in miR-455-3p-mimic group of RAW264.7 cells treated with RANKL, but decreased in inhibitor group. Luciferase assay proved that miR-455-3p targeted PTEN. We took a further step and found overexpression of PTEN significantly inhibited the increased proliferation and osteoblast differentiation of RAW264.7 cells induced by miR-455-3p. CONCLUSIONS: Our findings supported basic to explore the molecular mechanism of proliferation and osteoblast differentiation of RAW264.7 cells.


Assuntos
MicroRNAs , Osteoclastos , Osteogênese , PTEN Fosfo-Hidrolase , Animais , Proliferação de Células/genética , Camundongos , MicroRNAs/metabolismo , Osteoclastos/citologia , Osteogênese/genética , PTEN Fosfo-Hidrolase/genética , PTEN Fosfo-Hidrolase/metabolismo , Células RAW 264.7
8.
Stem Cells ; 40(2): 133-148, 2022 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-35257186

RESUMO

The N-terminal caveolin-binding motif (CBM) in Na/K-ATPase (NKA) α1 subunit is essential for cell signaling and somitogenesis in animals. To further investigate the molecular mechanism, we have generated CBM mutant human-induced pluripotent stem cells (iPSCs) through CRISPR/Cas9 genome editing and examined their ability to differentiate into skeletal muscle (Skm) cells. Compared with the parental wild-type human iPSCs, the CBM mutant cells lost their ability of Skm differentiation, which was evidenced by the absence of spontaneous cell contraction, marker gene expression, and subcellular myofiber banding structures in the final differentiated induced Skm cells. Another NKA functional mutant, A420P, which lacks NKA/Src signaling function, did not produce a similar defect. Indeed, A420P mutant iPSCs retained intact pluripotency and ability of Skm differentiation. Mechanistically, the myogenic transcription factor MYOD was greatly suppressed by the CBM mutation. Overexpression of a mouse Myod cDNA through lentiviral delivery restored the CBM mutant cells' ability to differentiate into Skm. Upstream of MYOD, Wnt signaling was demonstrated from the TOPFlash assay to have a similar inhibition. This effect on Wnt activity was further confirmed functionally by defective induction of the presomitic mesoderm marker genes BRACHYURY (T) and MESOGENIN1 (MSGN1) by Wnt3a ligand or the GSK3 inhibitor/Wnt pathway activator CHIR. Further investigation through immunofluorescence imaging and cell fractionation revealed a shifted membrane localization of ß-catenin in CBM mutant iPSCs, revealing a novel molecular component of NKA-Wnt regulation. This study sheds light on a genetic regulation of myogenesis through the CBM of NKA and control of Wnt/ß-catenin signaling.


Assuntos
Quinase 3 da Glicogênio Sintase , beta Catenina , Animais , Caveolina 1/genética , Caveolina 1/metabolismo , Caveolina 1/farmacologia , Diferenciação Celular , Quinase 3 da Glicogênio Sintase/metabolismo , Quinase 3 da Glicogênio Sintase/farmacologia , Camundongos , Desenvolvimento Muscular/genética , ATPase Trocadora de Sódio-Potássio/genética , ATPase Trocadora de Sódio-Potássio/metabolismo , Via de Sinalização Wnt , beta Catenina/metabolismo
9.
Prostate ; 81(10): 667-682, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33956349

RESUMO

The surface expression of Na/K-ATPase α1 (NKA) is significantly reduced in primary prostate tumors and further decreased in bone metastatic lesions. Here, we show that the loss of cell surface expression of NKA induces epithelial-mesenchymal transition (EMT) and promotes metastatic potential and tumor growth of prostate cancer (PCa) by decreasing the expression of E-cadherin and increasing c-Myc expression via the activation of Src/FAK pathways. Mechanistically, reduced surface expression of NKA in PCa is due to increased endocytosis through the activation of NKA/Src receptor complex. Using a high-throughput NKA ligand-screening platform, we have discovered MB5 as an inverse agonist of the NKA/Src receptor complex, capable of blocking the endocytosis of NKA. MB5 treatment increased NKA expression and E-cadherin in PCa cells, which reversed EMT and consequently decreased the invasion and growth of spheroid models and tumor xenografts. Thus, we have identified a hitherto unrecognized mechanism that regulates EMT and invasiveness of PCa and demonstrated for the first time the feasibility of identifying inverse agonists of receptor NKA/Src complex and their potential utility as anticancer drugs. We, therefore, conclude that cell surface expression of α1 NKA can be targeted for the development of new therapeutics against aggressive PCa and that MB5 may serve as a prototype for drug development against EMT in metastatic PCa.


Assuntos
Agonismo Inverso de Drogas , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Transição Epitelial-Mesenquimal/fisiologia , Neoplasias da Próstata/metabolismo , ATPase Trocadora de Sódio-Potássio/biossíntese , Animais , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/farmacologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Ouabaína/farmacologia , Tiamina/análogos & derivados , Tiamina/farmacologia , Tiamina/uso terapêutico , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
10.
Int J Mol Sci ; 22(7)2021 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-33801629

RESUMO

The Na/K-ATPase is the specific receptor for cardiotonic steroids (CTS) such as ouabain and digoxin. At pharmacological concentrations used in the treatment of cardiac conditions, CTS inhibit the ion-pumping function of Na/K-ATPase. At much lower concentrations, in the range of those reported for endogenous CTS in the blood, they stimulate hypertrophic growth of cultured cardiac myocytes through initiation of a Na/K-ATPase-mediated and reactive oxygen species (ROS)-dependent signaling. To examine a possible effect of endogenous concentrations of CTS on cardiac structure and function in vivo, we compared mice expressing the naturally resistant Na/K-ATPase α1 and age-matched mice genetically engineered to express a mutated Na/K-ATPase α1 with high affinity for CTS. In this model, total cardiac Na/K-ATPase activity, α1, α2, and ß1 protein content remained unchanged, and the cardiac Na/K-ATPase dose-response curve to ouabain shifted to the left as expected. In males aged 3-6 months, increased α1 sensitivity to CTS resulted in a significant increase in cardiac carbonylated protein content, suggesting that ROS production was elevated. A moderate but significant increase of about 15% of the heart-weight-to-tibia-length ratio accompanied by an increase in the myocyte cross-sectional area was detected. Echocardiographic analyses did not reveal any change in cardiac function, and there was no fibrosis or re-expression of the fetal gene program. RNA sequencing analysis indicated that pathways related to energy metabolism were upregulated, while those related to extracellular matrix organization were downregulated. Consistent with a functional role of the latter, an angiotensin-II challenge that triggered fibrosis in the α1r/rα2s/s mouse failed to do so in the α1s/sα2s/s. Taken together, these results are indicative of a link between circulating CTS, Na/K-ATPase α1, ROS, and physiological cardiac hypertrophy in mice under baseline laboratory conditions.


Assuntos
Glicosídeos Cardíacos/química , Coração/fisiologia , Miocárdio/enzimologia , ATPase Trocadora de Sódio-Potássio/genética , Angiotensina II/farmacologia , Animais , Cardiomegalia/patologia , Modelos Animais de Doenças , Ecocardiografia , Coração/efeitos dos fármacos , Masculino , Camundongos , Mutação , Ouabaína/farmacologia , Isoformas de Proteínas , RNA-Seq , Espécies Reativas de Oxigênio , Transdução de Sinais/efeitos dos fármacos
11.
Acta Physiol (Oxf) ; 232(3): e13652, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33752256

RESUMO

AIM: Highly prevalent diseases such as insulin resistance and heart failure are characterized by reduced metabolic flexibility and reserve. We tested whether Na/K-ATPase (NKA)-mediated regulation of Src kinase, which requires two NKA sequences specific to the α1 isoform, is a regulator of metabolic capacity that can be targeted pharmacologically. METHODS: Metabolic capacity was challenged functionally by Seahorse metabolic flux analyses and glucose deprivation in LLC-PK1-derived cells expressing Src binding rat NKA α1, non-Src-binding rat NKA α2 (the most abundant NKA isoform in the skeletal muscle), and Src binding gain-of-function mutant rat NKA α2. Mice with skeletal muscle-specific ablation of NKA α1 (skα1-/-) were generated using a MyoD:Cre-Lox approach and were subjected to treadmill testing and Western diet. C57/Bl6 mice were subjected to Western diet with or without pharmacological inhibition of NKA α1/Src modulation by treatment with pNaKtide, a cell-permeable peptide designed by mapping one of the sites of NKA α1/Src interaction. RESULTS: Metabolic studies in mutant cell lines revealed that the Src binding regions of NKA α1 are required to maintain metabolic reserve and flexibility. Skα1-/- mice had decreased exercise endurance and mitochondrial Complex I dysfunction. However, skα1-/- mice were resistant to Western diet-induced insulin resistance and glucose intolerance, a protection phenocopied by pharmacological inhibition of NKA α1-mediated Src regulation with pNaKtide. CONCLUSIONS: These results suggest that NKA α1/Src regulatory function may be targeted in metabolic diseases. Because Src regulatory capability by NKA α1 is exclusive to endotherms, it may link the aerobic scope hypothesis of endothermy evolution to metabolic dysfunction.


Assuntos
Dieta Ocidental , ATPase Trocadora de Sódio-Potássio/metabolismo , Animais , Camundongos , Fragmentos de Peptídeos , Ratos , Quinases da Família src/metabolismo
12.
Mol Pharmacol ; 99(3): 217-225, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33495275

RESUMO

Recent studies have revealed that Na/K-ATPase (NKA) can transmit signals through ion-pumping-independent activation of pathways relayed by distinct intracellular protein/lipid kinases, and endocytosis challenges the traditional definition that cardiotonic steroids (CTS) are NKA inhibitors. Although additional effects of CTS have long been suspected, revealing its agonist impact through the NKA receptor could be a novel mechanism in understanding the basic biology of NKA. In this study, we tested whether different structural CTS could trigger different sets of NKA/effector interactions, resulting in biased signaling responses without compromising ion-pumping capacity. Using purified NKA, we found that ouabain, digitoxigenin, and somalin cause comparable levels of NKA inhibition. However, although endogenous ouabain stimulates both protein kinases and NKA endocytosis, digitoxigenin and somalin bias to protein kinases and endocytosis, respectively, in LLC-PK1 cells. The positive inotropic effects of CTS are traditionally regarded as NKA inhibitors. However, CTS-induced signaling occurs at concentrations at least one order of magnitude lower than that of inotropy, which eliminates their well known toxic actions on the heart. The current study adds a novel mechanism that CTS could exert its biased signaling properties through the NKA signal transducer. SIGNIFICANCE STATEMENT: Although it is now well accepted that NKA has an ion-pumping-independent signaling function, it is still debated whether direct and conformation-dependent NKA/effector interaction is a key to this function. Therefore, this investigation is significant in advancing our understanding of the basic biology of NKA-mediated signal transduction and gaining molecular insight into the structural elements that are important for cardiotonic steroid's biased action.


Assuntos
Glicosídeos Cardíacos/farmacologia , Digitoxigenina/farmacologia , Glicosídeos/farmacologia , Ouabaína/farmacologia , Transdução de Sinais/efeitos dos fármacos , Animais , Sobrevivência Celular/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Células LLC-PK1 , ATPase Trocadora de Sódio-Potássio/metabolismo , Suínos
13.
J Neuroinflammation ; 17(1): 202, 2020 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-32631435

RESUMO

BACKGROUND: Spinal cord injury (SCI) triggers the primary mechanical injury and secondary inflammation-mediated injury. Neuroinflammation-mediated insult causes secondary and extensive neurological damage after SCI. Microglia play a pivotal role in the initiation and progression of post-SCI neuroinflammation. METHODS: To elucidate the significance of LRCH1 to microglial functions, we applied lentivirus-induced LRCH1 knockdown in primary microglia culture and tested the role of LRCH1 in microglia-mediated inflammatory reaction both in vitro and in a rat SCI model. RESULTS: We found that LRCH1 was downregulated in microglia after traumatic SCI. LRCH1 knockdown increased the production of pro-inflammatory cytokines such as IL-1ß, TNF-α, and IL-6 after in vitro priming with lipopolysaccharide and adenosine triphosphate. Furthermore, LRCH1 knockdown promoted the priming-induced microglial polarization towards the pro-inflammatory inducible nitric oxide synthase (iNOS)-expressing microglia. LRCH1 knockdown also enhanced microglia-mediated N27 neuron death after priming. Further analysis revealed that LRCH1 knockdown increased priming-induced activation of p38 mitogen-activated protein kinase (MAPK) and Erk1/2 signaling, which are crucial to the inflammatory response of microglia. When LRCH1-knockdown microglia were adoptively injected into rat spinal cords, they enhanced post-SCI production of pro-inflammatory cytokines, increased SCI-induced recruitment of leukocytes, aggravated SCI-induced tissue damage and neuronal death, and worsened the locomotor function. CONCLUSION: Our study reveals for the first time that LRCH1 serves as a negative regulator of microglia-mediated neuroinflammation after SCI and provides clues for developing novel therapeutic approaches against SCI.


Assuntos
Mediadores da Inflamação/metabolismo , Proteínas dos Microfilamentos/antagonistas & inibidores , Proteínas dos Microfilamentos/metabolismo , Microglia/metabolismo , Traumatismos da Medula Espinal/metabolismo , Animais , Células Cultivadas , Inflamação/induzido quimicamente , Inflamação/metabolismo , Inflamação/patologia , Lipopolissacarídeos/toxicidade , Masculino , Microglia/efeitos dos fármacos , Microglia/patologia , Ratos , Ratos Sprague-Dawley , Traumatismos da Medula Espinal/patologia
14.
Sci Adv ; 6(22): eaaw5851, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32537485

RESUMO

Several signaling events have been recognized as essential for regulating cell lineage specification and organogenesis in animals. We find that the gain of an amino-terminal caveolin binding motif (CBM) in the α subunit of the Na/K-adenosine triphosphatase (ATPase) (NKA) is required for the early stages of organogenesis in both mice and Caenorhabditis elegans. The evolutionary gain of the CBM occurred at the same time as the acquisition of the binding sites for Na+/K+. Loss of this CBM does not affect cell lineage specification or the initiation of organogenesis, but arrests further organ development. Mechanistically, this CBM is essential for the dynamic operation of Wnt and the timely up-regulation of transcriptional factors during organogenesis. These results indicate that the NKA was evolved as a dual functional protein that works in concert with Wnt as a hitherto unrecognized common mechanism to enable stem cell differentiation and organogenesis in multicellular organisms within the animal kingdom.


Assuntos
Caenorhabditis elegans , ATPase Trocadora de Sódio-Potássio , Animais , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Caveolina 1/metabolismo , Diferenciação Celular , Mamíferos/metabolismo , Camundongos , Organogênese/genética , ATPase Trocadora de Sódio-Potássio/genética , ATPase Trocadora de Sódio-Potássio/metabolismo
15.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 33(4): 462-466, 2019 Apr 15.
Artigo em Chinês | MEDLINE | ID: mdl-30983195

RESUMO

OBJECTIVE: To investigate the short-term effectiveness of modified tarsal sinus approach and traditional tarsal sinus approach in the treatment of Sanders Ⅱ-Ⅲ type calcaneal fractures. METHODS: Between January 2015 and August 2017, 53 patients with Sanders Ⅱ-Ⅲ type calcaneal fractures were selected and divided into observation group (21 cases, using modified tarsal sinus approach for fracture reduction after exposure of the subtalar joint below the long and short fibular tendon) and control group (32 cases, using traditional tarsal sinus approach) by random number method. There was no significant difference between the two groups in terms of gender, age, side, cause of injury, fracture type, injury to operation time, and preoperative Böhler angle, Gissane angle, visual analogue scale (VAS) core ( P>0.05), which were comparable. The operation time, postoperative drainage volume, postoperative Böhler angle, Gissane angle, and postoperative angle improvement values of the two groups were recorded and compared. VAS score, American Orthopaedic Foot and Ankle Society (AOFAS) score, and short-form 36 health survey scale (SF-36) score were used to evaluate the effectiveness. RESULTS: All the 53 patients successfully completed the operation without serious complications such as vascular and nerve injury and perioperative death. There was no significant difference in operation time and postoperative drainage volume between the two groups ( P>0.05). Patients in both groups were followed up 12-36 months (mean, 17 months). No infection, fracture displacement, failure of internal fixation, and malunion of fracture occurred after operation. None of the patients underwent secondary joint fusion. There was no significant difference in fracture healing time between the two groups ( t=0.30, P=0.77). The postoperative Böhler angle and Gissane angle at 2 days in the two groups were significantly improved when compared with those before operation ( P<0.05); however, there was no significant difference in Böhler angle, Gissane angle, and improvement value between the observation group and the control group at 2 days after operation ( P>0.05). VAS scores at 24 hours and 1 year after operation were significantly improved when compared with that before operation in both groups ( P<0.05). There was no significant difference in VAS scores between the two groups at 24 hours and 1 year after operation ( P>0.05). There was no significant difference in AOFAS scores between the two groups at 1 year after operation ( t=1.46, P=0.15). However, the SF-36 scale score at 1 year after operation was significantly higher than that of the control group ( t=2.08, P=0.04). At last follow-up, 2 patients in the observation group and 8 patients in the control group presented subtalar joint stiffness or pain, and there was no significant difference in the incidence between the two groups ( χ 2=1.98, P=0.16). CONCLUSION: The modified tarsal sinus approach for the treatment of Sanders Ⅱ-Ⅲ type calcaneal fractures has the advantages of minimal invasion, clear reduction under direct vision, reliable reduction and fixation, and low incision complications.


Assuntos
Traumatismos do Tornozelo , Calcâneo , Fraturas Ósseas , Traumatismos do Tornozelo/cirurgia , Calcâneo/lesões , Fixação Interna de Fraturas , Fraturas Ósseas/cirurgia , Humanos , Resultado do Tratamento
16.
Acta Biochim Biophys Sin (Shanghai) ; 51(3): 243-253, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30805592

RESUMO

A close relationship between cancer progression and microRNAs (miRNAs) regulation has been demonstrated. Abnormal microRNA-206 (miR-206) expression has been shown to be related to the development of malignancies. However, the role of miR-206 in hepatocellular carcinoma (HCC) remains unclear. Here, we evaluated the function of miR-206 in HCC. Results showed that miR-206 expression was decreased in 27 human HCC tissues compared with that of adjacent normal tissues. Conversely, cMET was up-regulated in human HCC cancer tissues, and cMET levels were shown to be negatively correlated with miR-206 expression. Abnormally increased miR-206 expression in three HCC cell lines (SMMC-7721, HepG2, and Huh7) attenuated cell viability, migration, and invasion. Increased apoptosis was also observed in these miR-206 expressing cells. Furthermore, we identified that miR-206 targets the 3'-UTR of the cMET gene for silencing, and restoration of cMET expression reversed the inhibitory effect of miR-206 on HCC. Tumor cells expressing miR-206 also showed delayed growth in the in vivo experiments compared with the controls. Altogether, our findings provide new insights into the molecular mechanisms of HCC oncogenesis.


Assuntos
Apoptose , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , MicroRNAs/fisiologia , Proteínas Proto-Oncogênicas c-met/genética , Adulto , Idoso , Animais , Carcinoma Hepatocelular/etiologia , Carcinoma Hepatocelular/genética , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Humanos , Neoplasias Hepáticas/etiologia , Neoplasias Hepáticas/genética , Camundongos , MicroRNAs/análise , Pessoa de Meia-Idade , Invasividade Neoplásica
17.
Oncotarget ; 10(67): 7181-7182, 2019 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-31903175

RESUMO

[This corrects the article DOI: 10.18632/oncotarget.8588.].

18.
J Environ Pathol Toxicol Oncol ; 38(4): 297-311, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32464002

RESUMO

Early development of liver cancer is usually asymptomatic. The overall survival rate of patients is relatively low due to late diagnosis, despite hepatocellular carcinoma being a common diagnosis. The high mortality rate of liver cancer was due to its overactivated cellular mitochondrial activities, namely thioredoxin reductase enzymatic activities and its downstream activation of nuclear factor kappa B (NF-κB) signaling pathways for cancer cell migration. Our previous study on this candidate compound on A2780 ovarian cancer cells and MCF-7 breast cancer cells, through modulation of cell-cycle checkpoints and respective targeted apoptosis pathways. The current study used HepG2 hepatocellular carcinoma cell lines as a representative in vitro liver cancer cell model. The half maximal inhibitory concentration (IC50) value was obtained via incubation of PTZ compound for 24 h yield of 37.03 µM, whereby it was three-fold more potent than the standard control tested, cisplatin (109.23 µM). The subsequent application of IC50 dosage of PTZ onto HepG2 cells illustrated a growth-static effect via activation of S-phase cell-cycle checkpoints, immediately followed by regulation of apoptosis. Increased cellular concentration of reactive oxygen species eventually generated oxidative damages on mitochondria, hence resulting in the release of cytochrome c protein and suppression of TrxR enzymatic activity, in conjunction with the suppression on invasion of cancer cells via Matrigel invasion chamber. In conclusion, PTZ was hypothesized to act effectively on mitochondria of HepG2 cells; hence it should proceed into detailed drug targeting mechanism research.


Assuntos
Apoptose/efeitos dos fármacos , Neoplasias Hepáticas/metabolismo , Mitocôndrias/efeitos dos fármacos , Fenotiazinas/toxicidade , Tiorredoxina Dissulfeto Redutase/metabolismo , Pontos de Checagem do Ciclo Celular , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Hep G2 , Humanos , Neoplasias Hepáticas/enzimologia
19.
Sci Rep ; 8(1): 12322, 2018 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-30120256

RESUMO

We report here the identification of α1 Na/K-ATPase as a major regulator of the proto-oncogene Src kinase and the role of this regulation in control of Warburg effect and tumor growth. Specifically, we discovered Y260 in α1 Na/K-ATPase as a Src-specific phosphorylation and binding site and that Y260 phosphorylation is required for Src-mediated signal transduction in response to a number of stimuli including EGF. As such, it enables a dynamic control of aerobic glycolysis. However, such regulation appears to be lost or attenuated in human cancers as the expression of Na/K-ATPase α1 was significantly decreased in prostate, breast and kidney cancers, and further reduced in corresponding metastatic lesions in patient samples. Consistently, knockdown of α1 Na/K-ATPase led to a further increase in lactate production and the growth of tumor xenograft. These findings suggest that α1 Na/K-ATPase works as a tumor suppressor and that a loss of Na/K-ATPase-mediated Src regulation may lead to Warburg phenotype in cancer.


Assuntos
Fosforilação/fisiologia , ATPase Trocadora de Sódio-Potássio/metabolismo , Quinases da Família src/metabolismo , Aerobiose/genética , Aerobiose/fisiologia , Animais , Proliferação de Células/genética , Proliferação de Células/fisiologia , Glicólise/genética , Glicólise/fisiologia , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fosforilação/genética , Proto-Oncogene Mas , Transdução de Sinais/genética , Transdução de Sinais/fisiologia , ATPase Trocadora de Sódio-Potássio/genética , Quinases da Família src/genética
20.
Oncotarget ; 7(20): 29245-54, 2016 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-27058417

RESUMO

RNA Polymerase II Elongation Factor (ELL)-associated factor 2 (EAF2) is a tumor suppressor frequently down-regulated in human prostate cancer. We previously reported that its binding partner ELL1 can enhance EAF2 protein stability and activity. Here we show that EAF2 can be polyubiquitinated and its degradation blocked by proteasome inhibitor. Co-immunoprecipitation detected EAF2 binding to SIAH2, an E3 ligase, and SIAH2 overexpression enhanced polyubiquitination of EAF2. Co-transfection of EAF2 binding partner ELL1 blocked EAF2 ubiquitination, providing a mechanism for EAF2 stabilization. Finally, EAF2K81R mutant, which exhibits reduced polyubiquitination and increased stability, was more potent than wild-type EAF2 in apoptosis induction. These findings suggest that SIAH2 is an E3 ligase for EAF2 polyubiquitination and ELL1 can enhance EAF2 level and function by blocking its polyubiquitination.


Assuntos
Proteínas Nucleares/metabolismo , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Fatores de Transcrição/metabolismo , Fatores de Elongação da Transcrição/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica/fisiologia , Humanos , Masculino , Ubiquitinação
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