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1.
Diabetes Obes Metab ; 26(7): 2839-2849, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38637979

RESUMO

AIM: To explore the link between the RBP4 rs3758539 genotype and metabolic syndrome risk factors and whether the impact of this genetic variation displays any potential race discrepancy. MATERIALS AND METHODS: This meta-analysis followed the PRISMA guidelines and was registered with PROSPERO (registration no. CRD42023407999). PubMed, Web of Science, Embase, Cochrane Library, Google Scholar, Airiti Library and CINAHL databases were used for the study search until October 2023. We evaluated the methodological quality using the Joanna Briggs Institute checklist and determined the correlation using a random-effects meta-analysis. RESULTS: The results indicated that individuals with the rs3758539 GA/AA genotype had a higher risk profile, including lower high-density lipoprotein levels [correlation: -0.045, 95% confidence interval (CI): -0.080 to -0.009, p = .015, I2 = 46.9%] and higher body mass index (correlation: 0.117, 95% CI: 0.036-0.197, p = .005, I2 = 82.0%), body fat (correlation: 0.098, 95% CI: 0.004-0.191, p = .041, I2 = 64.0%), and low-density lipoprotein levels (correlation: 0.074, 95% CI: 0.010-0.139, p = .024, I2 = 0%), of developing metabolic syndrome than those with the GG genotype. The subgroup analysis maintained a significantly positive correlation between the rs3758539 GA/AA genotype and body mass index (correlation: 0.163, 95% CI: 0.031-0.289, p = .016, I2 = 88.9%) but a negative correlation with high-density lipoprotein levels (correlation: -0.047, 95% CI: -0.087 to -0.006, p = .025, I2 = 65.7%) in the Asian group only. CONCLUSION: The current meta-analysis supports a significant link between the RBP4 rs3758539 GA/AA genotype and the metabolic syndrome.


Assuntos
Genótipo , Síndrome Metabólica , Proteínas Plasmáticas de Ligação ao Retinol , Síndrome Metabólica/genética , Humanos , Proteínas Plasmáticas de Ligação ao Retinol/genética , Polimorfismo de Nucleotídeo Único , Predisposição Genética para Doença , Fatores de Risco , Índice de Massa Corporal
2.
J Cell Physiol ; 234(7): 11265-11275, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30499104

RESUMO

Non-small-cell lung cancer (NSCLC) accounts for the majority of the lung cancer cases that have become a leading cause of cancer deaths worldwide. Overexpression of transcription factor forkhead box M1 (FOXM1) is involved in the inauspicious development of several types of cancer, including lung tumor aggressiveness. Our laboratory has previously found that MED28, a Mediator subunit for transcriptional activation, modulates cell growth, epithelial-mesenchymal transition, migration, and invasion in human breast cancer cells. The objective of the current study is to investigate the potential role of MED28 and FOXM1 in NSCLC. In addition to A549 and PC9 cells, we also used a doxycycline-inducible system to generate FOXM1-overexpressed A549-DN cells, and we explored the connection of MED28 with FOXM1 and their effect on migration. Herein, we report that the increased expression levels of both MED28 and FOXM1 elevated the expression of matrix metalloproteinase 2 (MMP2), a metastasis marker, which enhanced cell migration and matrigel invasion of NSCLC cells. Furthermore, MED28 interacted with FOXM1, and both exhibited a mutual effect on the expression and subcellular localization. Moreover, MED28 small interfering RNA-mediated MMP2 gene suppression could be attenuated by inducible expression of a constitutively active form of FOXM1, which consequently restored the migration and invasion ability of NSCLC cells. Our data indicate that MED28 interacts with FOXM1, and each affects the expression and localization of the other, and, more importantly, both regulate MMP2-dependent migration and invasion in human lung cancer cells.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/patologia , Proteína Forkhead Box M1/metabolismo , Neoplasias Pulmonares/patologia , Metaloproteinase 2 da Matriz/metabolismo , Complexo Mediador/metabolismo , Células A549 , Carcinoma Pulmonar de Células não Pequenas/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células , Transição Epitelial-Mesenquimal/genética , Proteína Forkhead Box M1/genética , Regulação Neoplásica da Expressão Gênica/genética , Células HEK293 , Humanos , Neoplasias Pulmonares/genética , Complexo Mediador/genética , Invasividade Neoplásica/genética , Interferência de RNA , RNA Interferente Pequeno/genética
3.
J Cell Physiol ; 234(4): 4375-4384, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30191992

RESUMO

Transcription factor high-mobility group box-containing protein 1 (HBP1) may function as a tumor suppressor in various types of cancer. In a previous study, we demonstrated that HBP1 suppressed cell invasion in oral cancer. To further understand the underlying mechanism, the current study is aimed at investigating how HBP1 exerts its antimetastatic potential in oral cancer. In a cell model, ectopic expression of HBP1 potently suppressed epithelial-mesenchymal transition, cellular migration, and invasion; conversely, HBP1 knockdown promoted these malignant phenotypes. The matrix metalloproteinase (MMP) family is highly implicated in tumor metastasis. Therefore, we examined the effect of HBP1 on the activation of the MMP members, MMP-2, -9, and -13 that are highly associated with the aggressiveness of oral cancer. Ectopic expression of HBP1 resulted in a mild reduction in the expression and activity of MMP-2 and -9, yet it had a potent inhibitory effect on MMP-13. In contrast, HBP1 knockdown strongly enhanced the activation of MMP-13. Further, we demonstrated that MMP-13 is a target of HBP1 transcription repression as evidenced by the identification of an HBP1 binding site in the cis proximal region of the MMP-13 promoter. More important, MMP-13 knockdown significantly alleviated HBP1 small interfering RNA-mediated promotion in cell invasion. Analysis of oral tumor specimens revealed that the low HBP1 (<0.3-fold)/high MMP-13 (>3-fold) status was associated with metastatic potential. All told, our study provides evidence supporting the idea that the HBP1-MMP-13 axis is a key regulator of the aggressiveness in oral cancer.


Assuntos
Movimento Celular , Proteínas de Grupo de Alta Mobilidade/metabolismo , Metaloproteinase 13 da Matriz/metabolismo , Neoplasias Bucais/enzimologia , Proteínas Repressoras/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço/enzimologia , Sítios de Ligação , Linhagem Celular Tumoral , Transição Epitelial-Mesenquimal , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Proteínas de Grupo de Alta Mobilidade/genética , Humanos , Metaloproteinase 13 da Matriz/genética , Neoplasias Bucais/genética , Neoplasias Bucais/patologia , Invasividade Neoplásica , Regiões Promotoras Genéticas , Proteínas Repressoras/genética , Transdução de Sinais , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/secundário
4.
J Cell Physiol ; 233(5): 4205-4215, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29030964

RESUMO

Transcription factor HMG box-containing protein 1 (HBP1) has been found to be up-regulated in rat adipose tissue and differentiated preadipocyte; however, how HBP1 is involved in adipocyte formation remains unclear. In the present study, we demonstrated that under a standard differentiation protocol HBP1 expression fluctuates with down-regulation in the mitotic clonal expansion (MCE) stage followed by up-regulation in the terminal differentiation stage in both 3T3-L1 and MEF cell models. Also, HBP1 knockdown accelerated cell cycle progression in the MCE stage, but it impaired final adipogenesis. To gain further insight into the role of HBP1 in the MCE stage, we found that the HBP1 expression pattern is reciprocal to that of C/EBPß, and ectopic expression of HBP1suppresses C/EBPß expression. These data indicate that HBP1 functions as a negative regulator of MCE. In contrast, when HBP1 expression was gradually elevated along with a concomitant induction of C/EBPα at the end of the MCE, HBP1 knockdown leads to a significant reduction of C/EBPα expression, suggesting that HBP1-mediated C/EBPα expression may be needed for the termination of the cell cycle at the end of MCE for terminal differentiation. All told, our findings show that HBP1 is a key transcription factor in the already complicated regulatory cascade during adipocyte differentiation.


Assuntos
Adipogenia/genética , Diferenciação Celular/genética , Proteínas de Grupo de Alta Mobilidade/genética , Proteínas Repressoras/genética , Células 3T3-L1 , Adipócitos/citologia , Animais , Proteína alfa Estimuladora de Ligação a CCAAT/genética , Proteína beta Intensificadora de Ligação a CCAAT/genética , Ciclo Celular/genética , Regulação da Expressão Gênica no Desenvolvimento , Técnicas de Silenciamento de Genes , Camundongos , Mitose/genética , Ratos , Ativação Transcricional/genética
5.
J Cell Physiol ; 232(6): 1337-1345, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27662245

RESUMO

MED28, a mammalian Mediator subunit, was found highly expressed in several types of malignancy, including breast cancer. Recently, we have identified a role of MED28 in regulating both cell growth and migration in human breast cancer cells. In epithelium-derived solid tumor, migration and invasion are preceded by the progression of epithelial-mesenchymal transition (EMT) which calls for downregulation of epithelial markers as well as upregulation of mesenchymal markers, among other features. The objective of this study was to investigate a putative role of MED28 in the progression of EMT in human breast cancer cells. In fibroblast-like MDA-MB-231 cells, suppression of MED28 attenuated the mesenchymal morphology, concomitantly with a reduction of several mesenchymal biomarkers and Snail, a transcriptional repressor of E-cadherin. The suppression effect was also accompanied by downregulation of p-NFκB/p65. However, overexpression of MED28 exhibited in an opposite manner. In epithelial MCF7 cells, administration of Adriamycin®, an experimental EMT induction system, led to a mesenchyme-like appearance correlated with increased expression of MED28, p-p65, and Snail, and a reciprocal change of epithelial and mesenchymal markers. Furthermore, suppression of MED28 attenuated the experimental EMT effect and restored the original expression status of E-cadherin and MMP9 in MCF7 cells. Our data indicate that MED28 modulates the development of EMT through NFκB in human breast cancer cells, further reinforcing the significance of MED28 in the progression of breast cancer on top of its role in cell growth and migration. J. Cell. Physiol. 232: 1337-1345, 2017. © 2016 Wiley Periodicals, Inc.


Assuntos
Neoplasias da Mama/patologia , Transição Epitelial-Mesenquimal , Complexo Mediador/metabolismo , NF-kappa B/metabolismo , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Forma Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/farmacologia , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Feminino , Humanos , Modelos Biológicos , Fenótipo , Transdução de Sinais/efeitos dos fármacos , Fatores de Transcrição da Família Snail/metabolismo
6.
J Immunol ; 195(7): 3355-64, 2015 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-26304992

RESUMO

Accumulating evidence indicates that subchondral bone might play an essential role in rheumatoid arthritis (RA). Osteopontin (OPN) induces the production of an important proinflammatory cytokine involved in the pathogenesis of RA. This study evaluated the activation of oncostatin M (OSM) by OPN in human primary osteoblasts to understand RA pathogenesis and characterized the intracellular signaling pathways involved in this activation. Quantitative PCR, ELISA, and Western blot results indicated that stimulation of human primary osteoblasts with OPN induces OSM expression through αvß3 integrin/c-Src/platelet-derived growth factor receptor transactivation/MEK/ERK. Treatment of osteoblasts with OPN also increased c-Jun phosphorylation, AP-1 luciferase activity, and c-Jun binding to the AP-1 element on the OSM promoter, as demonstrated using chromatin immunoprecipitation assay. Moreover, inhibition of OPN expression using lentiviral-OPN short hairpin RNA resulted in the amelioration of articular swelling, cartilage erosion, and OSM expression in the ankle joint of mice with collagen-induced arthritis as shown using microcomputed tomography and immunohistochemistry staining. Our results imply that OSM expression in osteoblasts increases in response to OPN-induced inflammation in vitro. Finally, lentiviral-OPN short hairpin RNA ameliorates the inflammatory response and bone destruction in mice with collagen-induced arthritis. Therefore, OPN may be a potential therapeutic target for RA.


Assuntos
Artrite Experimental/patologia , Artrite Reumatoide/patologia , Oncostatina M/biossíntese , Osteoblastos/metabolismo , Osteopontina/metabolismo , Adulto , Animais , Artrite Reumatoide/terapia , Linhagem Celular , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Células HEK293 , Humanos , Integrina alfaVbeta3/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno/genética , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Oncostatina M/genética , Osteopontina/genética , Fosforilação , Regiões Promotoras Genéticas/genética , Ligação Proteica , Proteínas Proto-Oncogênicas pp60(c-src)/metabolismo , Interferência de RNA , RNA Interferente Pequeno , Receptor beta de Fator de Crescimento Derivado de Plaquetas/genética , Receptores do Fator de Crescimento Derivado de Plaquetas/metabolismo , Transdução de Sinais/fisiologia , Fator de Transcrição AP-1/metabolismo
7.
J Cell Physiol ; 231(8): 1796-803, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26660958

RESUMO

Vitamin A is required for normal body function, including vision, epithelial integrity, growth, and differentiation. All trans-retinoic acid (ATRA), a family member of vitamin A, has been explored in treating acute promyelocytic leukemia and other types of cancer. Dysregulated Wnt/ß-catenin signaling and disrupted cadherin-catenin complex often contribute to colorectal malignancy. MED28, a mammalian Mediator subunit, is found highly expressed in breast and colorectal cancers. Our laboratory has also reported that MED28 regulates cell growth, migration, and invasion in human breast cancer cells. In the current study we investigated the effect of ATRA on MED28 and Wnt/ß-catenin signaling in colorectal cancer. HCT116, HT29, SW480, and SW620, four human colorectal cancer cell lines representing different stages of carcinogenesis and harboring critical genetic changes, were employed. Our data indicated that regardless of genetic variations among these cells, suppression of MED28 reduced the expression of cyclin D1, c-Myc, and nuclear ß-catenin, but increased the expression of E-cadherin and HMG box-containing protein 1 (HBP1) where HBP1 has been described as a negative regulator of the Wnt/ß-catenin signaling. The reporter activity of an HBP1 promoter increased upon MED28 knockdown, but decreased upon MED28 overexpression. ATRA reduced the expression of MED28 and mimicked the effect of MED28 suppression in down-regulating Wnt/ß-catenin signaling. Taken together, ATRA can reverse the suppressive effect of MED28 on HBP1 and E-cadherin and inactivate the Wnt/ß-catenin pathway in colorectal cancer, suggesting a protective effect of ATRA against colorectal cancer. J. Cell. Physiol. 231: 1796-1803, 2016. © 2015 Wiley Periodicals, Inc.


Assuntos
Antineoplásicos/farmacologia , Neoplasias Colorretais/tratamento farmacológico , Proteínas de Grupo de Alta Mobilidade/metabolismo , Complexo Mediador/metabolismo , Proteínas Repressoras/metabolismo , Transdução de Sinais/efeitos dos fármacos , Tretinoína/farmacologia , beta Catenina/metabolismo , Antígenos CD , Caderinas/genética , Caderinas/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Ciclina D1/genética , Ciclina D1/metabolismo , Relação Dose-Resposta a Droga , Regulação Neoplásica da Expressão Gênica , Células HCT116 , Células HT29 , Proteínas de Grupo de Alta Mobilidade/genética , Humanos , Complexo Mediador/genética , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Interferência de RNA , Proteínas Repressoras/genética , Transfecção , beta Catenina/genética
8.
Stem Cells ; 33(7): 2243-55, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25828083

RESUMO

Endothelial progenitor cells (EPCs) promote angiogenesis and are therefore key contributors to a wide variety of angiogenesis-related autoimmune diseases such as rheumatoid arthritis (RA). However, the signaling mechanisms through which these progenitor cells influence RA pathogenesis remain unknown. The aim of this study was to examine whether resistin plays a role in the pathogenesis of and angiogenesis associated with RA by circulating EPCs. We found that levels of resistin in synovial fluid and tissue from patients with RA and from mice with collagen-induced arthritis were overexpressed and promoted the homing of EPCs into the synovium, thereby inducing angiogenesis. EPCs isolated from healthy donors were used to investigate the signal transduction pathway underlying EPC migration and tube formation after treatment with resistin. We found that resistin directly induced a significant increase in expression of vascular endothelial growth factor (VEGF) in EPCs. We also found that the expression of microRNA-206 (miR-206) was negatively correlated with the expression of resistin during EPC-mediated angiogenesis. Notably, the increased expression of VEGF was associated with decreased binding of miR-206 to the VEGF-A 3' untranslated region through protein kinase C delta-dependent AMP-activated protein kinase signaling pathway. Moreover, blockade of resistin reduced EPC homing into synovial fluid and angiogenesis in vivo. Taken together, our study is the first to demonstrate that resistin promotes EPCs homing into the synovium during RA angiogenesis via a signal transduction pathway that involves VEGF expression in primary EPCs. These findings provide support for resistin as a therapeutic target for the patients with RA. Stem Cells 2015;33:2243-2255.


Assuntos
Artrite Reumatoide/genética , Artrite Reumatoide/metabolismo , Células Progenitoras Endoteliais/metabolismo , MicroRNAs/metabolismo , Neovascularização Patológica/patologia , Adulto , Animais , Embrião de Galinha , Feminino , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Resistina , Transfecção
9.
Clin Sci (Lond) ; 130(9): 667-81, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26811540

RESUMO

Arthritis is a process of chronic inflammation that results in joint damage. IL (interleukin)-1ß is an inflammatory cytokine that acts as a key mediator of cartilage degradation, and is abundantly expressed in arthritis. Neovascularization is one of the pathological characteristics of arthritis. However, the role of IL-1ß in the angiogenesis of chondrocytes remains unknown. In the present study, we demonstrate that stimulating chondrocytes (ATDC5) with IL-1ß increased the expression of FGF (fibroblast growth factor)-2, a potent angiogenic inducer, and then promoted EPC (endothelial progenitor cell) tube formation and migration. In addition, FGF-2-neutralizing antibody abolished ATDC5-conditional medium-mediated angiogenesis in vitro, as well as its angiogenic effects in the CAM (chick chorioallantoic membrane) assay and Matrigel plug nude mice model in vivo. IHC (immunohistochemistry) staining from a CIA (collagen-induced arthritis) mouse model also demonstrates that arthritis increased the expression of IL-1ß and FGF-2, as well as EPC homing in articular cartilage. Moreover, IL-1ß-induced FGF-2 expression via IL-1RI (type-1 IL-1 receptor), ROS (reactive oxygen species) generation, AMPK (AMP-activated protein kinase), p38 and NF-κB (nuclear factor κB) pathway has been demonstrated. On the basis of these findings, we conclude that IL-1ß promotes FGF-2 expression in chondrocytes through the ROS/AMPK/p38/NF-κB signalling pathway and subsequently increases EPC angiogenesis. Therefore IL-1ß serves as a link between inflammation and angiogenesis during arthritis.


Assuntos
Condrócitos/citologia , Células Progenitoras Endoteliais/metabolismo , Fator 2 de Crescimento de Fibroblastos/metabolismo , Interleucina-1beta/farmacologia , Neovascularização Fisiológica/efeitos dos fármacos , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Artrite Experimental/metabolismo , Artrite Experimental/patologia , Linhagem Celular , Galinhas , Condrócitos/efeitos dos fármacos , Condrócitos/metabolismo , Modelos Animais de Doenças , Células Progenitoras Endoteliais/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Humanos , Articulações/efeitos dos fármacos , Articulações/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Receptores de Interleucina/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
10.
Clin Sci (Lond) ; 130(17): 1523-33, 2016 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-27252405

RESUMO

Chondrosarcoma is the second most frequently occurring type of bone malignancy characterized by distant metastatic propensity. Vascular endothelial growth factor-C (VEGF-C) is the major lymphangiogenic factor, and makes crucial contributions to tumour lymphangiogenesis and lymphatic metastasis. Adiponectin is a protein hormone secreted predominantly by differentiated adipocytes. In recent years, adiponectin has also been indicated as facilitating tumorigenesis, angiogenesis and metastasis. However, the effect of adiponectin on VEGF-C regulation and lymphangiogenesis in chondrosarcoma has remained largely a mystery. In the present study, we have shown a clinical correlation between adiponectin and VEGF-C, as well as tumour stage, in human chondrosarcoma tissues. We further demonstrated that adiponectin promoted VEGF-C expression and secretion in human chondrosarcoma cells. The conditioned medium from adiponectin-treated cells significantly induced tube formation and migration of human lymphatic endothelial cells. In addition, adiponectin knock down inhibited lymphangiogenesis in vitro and in vivo We also found that adiponectin-induced VEGF-C is mediated by the calmodulin-dependent protein kinase II (CaMKII), AMP-activated protein kinase (AMPK) and p38 signaling pathway. Furthermore, the expression of miR-27b was negatively regulated by adiponectin via the CaMKII, AMPK and p38 cascade. The present study is the first to describe the mechanism of adiponectin-promoted lymphangiogenesis by up-regulating VEGF-C expression in chondrosarcomas. Thus, adiponectin could serve as a therapeutic target in chondrosarcoma metastasis and lymphangiogenesis.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Adiponectina/metabolismo , Condrossarcoma/metabolismo , Linfangiogênese , MicroRNAs/metabolismo , Fator C de Crescimento do Endotélio Vascular/metabolismo , Proteínas Quinases Ativadas por AMP/genética , Adiponectina/genética , Animais , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/genética , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Linhagem Celular Tumoral , Condrossarcoma/enzimologia , Condrossarcoma/genética , Humanos , Sistema de Sinalização das MAP Quinases , Masculino , Camundongos , Camundongos Nus , MicroRNAs/genética , Fator C de Crescimento do Endotélio Vascular/genética , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
11.
Biochim Biophys Acta ; 1843(5): 846-54, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24462773

RESUMO

Osteosarcoma is the most common primary malignant tumor, and its treatments require more effective therapeutic approaches. Paclitaxel has a broad range of antitumor activities, including apoptosis-inducing effects. However, the majority of tumors in patients with advanced cancer eventually develop chemoresistance. Connective tissue growth factor (CTGF) is a secreted protein that modulates the invasiveness of certain human cancer cells by binding to integrins. However, the effect of CTGF in paclitaxel-mediated chemotherapy is unknown. Here, we report that the expression of CTGF in osteosarcoma patients was significantly higher than that of the CTGF expression in normal bone tissues. Overexpression of CTGF increased the resistance to paclitaxel-mediated cell apoptosis. In contrast, knockdown of CTGF expression by CTGF shRNA increased the chemotherapeutic effect of paclitaxel. In addition, CTGF increased resistance to paclitaxel-induced apoptosis through upregulation of survivin expression. Moreover, the AMP-activated protein kinase (AMPK)-dependent nuclear factor kappa B (NF-κB) pathway mediated paclitaxel-increased chemoresistance and survivin expression. In a mouse xenograft model, overexpression of CTGF promoted resistance to paclitaxel. In contrast, knockdown of CTGF expression increased the therapeutic effect of paclitaxel in this model. In conclusion, our data indicate that CTGF might be a critical oncogene of human osteosarcoma involved in resistance to paclitaxel treatment.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Fator de Crescimento do Tecido Conjuntivo/fisiologia , Resistencia a Medicamentos Antineoplásicos/fisiologia , Proteínas Inibidoras de Apoptose/fisiologia , Osteossarcoma/patologia , Paclitaxel/farmacologia , Regulação para Cima/fisiologia , Animais , Linhagem Celular Tumoral , Humanos , Marcação In Situ das Extremidades Cortadas , Camundongos , Camundongos Nus , Reação em Cadeia da Polimerase em Tempo Real , Survivina
12.
Biochim Biophys Acta ; 1833(5): 966-75, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23313051

RESUMO

CCN4 is a cysteine-rich protein that belongs to the Cyr61, CTGF, Nov family of matricellular proteins. Here, we investigated the intracellular signaling pathways involved in CCN4-induced vascular cell adhesion molecule-1 expression in human osteoarthritis synovial fibroblasts. Stimulation of OASFs with CCN4 induced VCAM-1 expression. CCN4-induced VCAM-1 expression was attenuated by αvß5 or α6ß1 integrin antibody, Syk inhibitor, PKCδ inhibitor (rottlerin), JNK inhibitor (SP600125), and AP-1 inhibitors (curcumin and tanshinone). Stimulation of cells with CCN4 increased Syk, PKCδ, and JNK activation. Treatment of OASFs with CCN4 also increased c-Jun phosphorylation, AP-1-luciferase activity, and c-Jun binding to the AP-1 element in the VCAM-1 promoter. Moreover, up-regulation of VCAM-1 increased the adhesion of monocytes to OASF monolayers, and this adhesion was attenuated by transfection with a VCAM-1 siRNA. Our results suggest that CCN4 increases VCAM-1 expression in human OASFs via the Syk, PKCδ, JNK, c-Jun, and AP-1 signaling pathways. The CCN4-induced VCAM-1 expression promoted monocyte adhesion to human OASFs.


Assuntos
Osteoartrite , Líquido Sinovial , Molécula 1 de Adesão de Célula Vascular/metabolismo , Proteínas de Sinalização Intercelular CCN/genética , Proteínas de Sinalização Intercelular CCN/metabolismo , Adesão Celular , Fator de Crescimento do Tecido Conjuntivo/metabolismo , Proteína Rica em Cisteína 61/metabolismo , Fibroblastos/citologia , Fibroblastos/metabolismo , Fibroblastos/patologia , Regulação da Expressão Gênica , Humanos , Monócitos/citologia , Monócitos/metabolismo , Proteína Sobre-Expressa em Nefroblastoma/metabolismo , Osteoartrite/metabolismo , Osteoartrite/patologia , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , Transdução de Sinais , Líquido Sinovial/citologia , Líquido Sinovial/metabolismo , Molécula 1 de Adesão de Célula Vascular/genética
13.
Arthritis Rheum ; 64(10): 3344-54, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22674286

RESUMO

OBJECTIVE: Thrombin is a key factor involved in the stimulation of fibrin deposition, angiogenesis, and proinflammatory processes. Abnormalities in these processes are primary features of rheumatoid arthritis (RA). The aim of this study was to investigate the intracellular signaling pathways involved in thrombin-induced CCL2 expression in human osteoblasts. METHODS: Thrombin-mediated CCL2 expression was assessed by quantitative polymerase chain reaction and enzyme-linked immunosorbent assay. The mechanisms of action of thrombin in different signaling pathways were studied using Western blotting. Knockdown of protease-activated receptor (PAR) protein was achieved by small interfering RNA (siRNA) transfection. Chromatin immunoprecipitation assays were used to study in vivo binding of c-Jun to the CCL2 promoter. Transient transfection was used to examine activator protein 1 (AP-1) activity. RESULTS: Stimulation of human primary osteoblasts and MG-63 cells with thrombin induced CCL2 expression. PAR-1-specific siRNA (but not other PAR siRNA) was involved in thrombin-mediated up-regulation of CCL2. Thrombin-mediated CCL2 production was attenuated by the thrombin inhibitor PPACK, the protein kinase Cδ (PKCδ) inhibitor rottlerin, the c-Src inhibitor PP2, epidermal growth factor receptor (EGFR) inhibitor AG-1478, MEK inhibitors PD98059 and U0126, or AP-1 inhibitors curcumin and tanshinone IIA. Stimulation of cells with thrombin increased PKCδ, c-Src, EGFR, MEK, and ERK activation. Treatment of osteoblasts with thrombin also increased c-Jun phosphorylation, AP-1 luciferase activity, and c-Jun binding to the AP-1 element on the CCL2 promoter. CONCLUSION: Our results suggest that the interaction between thrombin and PAR-1 increases CCL2 expression in human osteoblasts via the PKCδ/c-Src/ EGFR transactivation/MEK/ERK/c-Jun/AP-1 pathway.


Assuntos
Quimiocina CCL2/metabolismo , Receptores ErbB/metabolismo , Osteoblastos/metabolismo , Transdução de Sinais/efeitos dos fármacos , Trombina/farmacologia , Acetofenonas/farmacologia , Adulto , Clorometilcetonas de Aminoácidos/farmacologia , Benzopiranos/farmacologia , Quimiocina CCL2/genética , Inibidores Enzimáticos/farmacologia , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/genética , Humanos , Pessoa de Meia-Idade , Osteoblastos/efeitos dos fármacos , Proteína Quinase C/antagonistas & inibidores , Pirimidinas/farmacologia , Quinazolinas/farmacologia , Receptor PAR-1/genética , Receptor PAR-1/metabolismo , Transdução de Sinais/fisiologia , Ativação Transcricional/efeitos dos fármacos , Tirfostinas/farmacologia , Quinases da Família src/antagonistas & inibidores
14.
Mediators Inflamm ; 2013: 326041, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24385683

RESUMO

Thrombin is a key mediator of fibrin deposition, angiogenesis, and proinflammatory processes. Abnormalities in these processes are primary features of rheumatoid arthritis and osteoarthritis. Matrix metalloproteinase-13 (MMP-13) may contribute to the breakdown of articular cartilage during arthritis. However, the role of thrombin in MMP-13 production in chondrocytes is unknown. In this study, we investigated the intracellular signaling pathways involved in thrombin-induced MMP-13 expression in human chondrocytes. We found that stimulation with thrombin led to increased secretion of MMP-13 in cultured human chondrocytes. Further, this thrombin-induced MMP-13 production was reduced after transfection with siRNAs against protease activated receptors 1 and 3 (PAR1 and PAR3), but not with PAR4 siRNA. Treatment with specific inhibitors for PKCδ, c-Src, EGFR, PI3K, Akt, or AP-1 or with the corresponding siRNAs against these signaling proteins also abolished the thrombin-mediated increase in MMP-13 production in chondrocytes. Our results provide evidence that thrombin acts through the PAR1/PAR3 receptors and activates PKCδ and c-Src, resulting in EGFR transactivation and activation of PI3K, Akt, and finally AP-1 on the MMP-13 promoter, thereby contributing to cartilage destruction during arthritis.


Assuntos
Condrócitos/enzimologia , Metaloproteinase 13 da Matriz/genética , Transdução de Sinais , Trombina/farmacologia , Artrite Reumatoide/etiologia , Proteína Tirosina Quinase CSK , Células Cultivadas , Receptores ErbB/fisiologia , Humanos , Osteoartrite/etiologia , Fosfatidilinositol 3-Quinases/fisiologia , Proteína Quinase C-delta/fisiologia , Proteínas Proto-Oncogênicas c-akt/fisiologia , RNA Mensageiro/análise , Receptor PAR-1/fisiologia , Transdução de Sinais/fisiologia , Fator de Transcrição AP-1/fisiologia , Quinases da Família src/fisiologia
15.
IEEE Trans Med Imaging ; 42(7): 2081-2090, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36378795

RESUMO

Dataset auditing for machine learning (ML) models is a method to evaluate if a given dataset is used in training a model. In a Federated Learning setting where multiple institutions collaboratively train a model with their decentralized private datasets, dataset auditing can facilitate the enforcement of regulations, which provide rules for preserving privacy, but also allow users to revoke authorizations and remove their data from collaboratively trained models. This paper first proposes a set of requirements for a practical dataset auditing method, and then present a novel dataset auditing method called Ensembled Membership Auditing ( EMA ). Its key idea is to leverage previously proposed Membership Inference Attack methods and to aggregate data-wise membership scores using statistic testing to audit a dataset for a ML model. We have experimentally evaluated the proposed approach with benchmark datasets, as well as 4 X-ray datasets (CBIS-DDSM, COVIDx, Child-XRay, and CXR-NIH) and 3 dermatology datasets (DERM7pt, HAM10000, and PAD-UFES-20). Our results show that EMA meet the requirements substantially better than the previous state-of-the-art method. Our code is at:https://github.com/Hazelsuko07/EMA.


Assuntos
Aprendizado de Máquina , Conjuntos de Dados como Assunto
16.
Adv Nutr ; 14(2): 352-362, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36806496

RESUMO

PUFA status is highly implicated in cognitive development and metabolic disorder-related diseases. Genetic variants of FADS genes encoding enzymes that catalyze the rate-limiting steps of PUFA biosynthesis appear to be associated with n-3 and n-6 PUFA contents. Therefore, we conducted the first systematic review and meta-analysis to explore the association of the A-allele carriers of the FADS1 rs174556 with PUFA status. The PRISMA guidelines were followed. The literature search was conducted up to November 2022 in PubMed, Web of Science, Embase, Cochrane Library, Airiti Library, and CINAHL. The Joanna Briggs Institute checklists were used to assess the methodological quality. The correlation with 95% CIs was determined by a random-effect meta-analysis. Eleven studies that met the inclusion criteria and acceptable quality were included in this systematic review. The data on PUFA contents were collected when they were mainly analyzed using blood samples and breast milk. Results of the meta-analysis on eight studies (one randomized controlled trial, one cohort study, and six cross-sectional studies) showed that the A-allele carriers of rs174556 were significantly negatively correlated with the concentrations of AA (P = 0.001), EPA (P = 0.004), and DHA (P = 0.025). However, ALA and LA were not associated with the A-allele carriers. To clarify the discrepancy, we further divided the studies into blood samples and breast milk subgroups. The subgroup analysis revealed that the A-allele carriers of rs174556 were significantly positively correlated with LA (P = 0.031) and negatively correlated with AA (P = 0.001), EPA (P = 0.036), and DHA (P < 0.001) in the blood sample group, but not in the breast milk group. The current meta-analysis proved that the A-allele carriers of the FADS1 rs174556 appeared to be highly associated with lower concentrations of AA, EPA, and DHA but higher LA in the blood samples. The study has been registered on the International Prospective Register of Systematic Reviews (PROSPERO:CRD42022363978). Adv Nutr 2023;x:xx-xx.


Assuntos
Ácidos Graxos Dessaturases , Polimorfismo de Nucleotídeo Único , Feminino , Humanos , Ácidos Graxos Dessaturases/genética , Ácidos Graxos Dessaturases/metabolismo , Estudos de Coortes , Estudos Transversais , Ácidos Graxos Insaturados , Genótipo , Ensaios Clínicos Controlados Aleatórios como Assunto
17.
Cells ; 12(1)2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36611972

RESUMO

Oral squamous cell carcinoma (OSCC) frequently carries high epidermal growth factor receptor (EGFR) expression. Erlotinib, a small molecule tyrosine kinase inhibitor (TKI), is an effective inhibitor of EGFR activity; however, resistance to this drug can occur, limiting therapeutic outcomes. Therefore, in the current study, we aimed to unveil key intracellular molecules and adjuvant reagents to overcome erlotinib resistance. First, two HSC-3-derived erlotinib-resistant cell lines, ERL-R5 and ERL-R10, were established; both exhibited relatively higher growth rates, glucose utilization, epithelial-mesenchymal transition (EMT), and invasiveness compared with parental cells. Cancer aggressiveness-related proteins, such as N-cadherin, Vimentin, Twist, MMP-2, MMP-9, and MMP-13, and the glycolytic enzymes PKM2 and GLUT1 were upregulated in ERL-R cells. Notably, ERL-R cells were sensitive to quercetin, a naturally-existing flavonol phytochemical with anti-cancer properties against various cancer cells. At a concentration of 5 µM, quercetin effectively arrested cell growth, reduced glucose utilization, and inhibited cellular invasiveness. An ERL-R5-derived xenograft mouse model confirmed the growth-inhibitory efficacy of quercetin. Additionally, knock-down of PKM2 by siRNA mimicked the effect of quercetin and re-sensitized ERL-R cells to erlotinib. Furthermore, adding quercetin blocked the development of erlotinib-mediated resistance by enhancing apoptosis. In conclusion, our data support the application of quercetin in anti-erlotinib-resistant OSCC and indicate that PKM2 is a determinant factor in erlotinib resistance and quercetin sensitivity.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Neoplasias Pulmonares , Neoplasias Bucais , Humanos , Animais , Camundongos , Cloridrato de Erlotinib/farmacologia , Cloridrato de Erlotinib/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma de Células Escamosas/tratamento farmacológico , Quercetina/farmacologia , Quercetina/uso terapêutico , Piruvato Quinase , Neoplasias Pulmonares/patologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos , Linhagem Celular Tumoral , Neoplasias Bucais/tratamento farmacológico , Receptores ErbB/metabolismo , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Glucose
18.
Food Chem Toxicol ; 171: 113554, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36509263

RESUMO

Abnormal accumulation of lipids in liver leads to uncontrolled endoplasmic reticulum (ER) stress and autophagy. Luteolin is known to have antioxidant, anti-inflammatory, and anti-cancer properties, but whether it protects against lipotoxicity in liver remains unclear. In this study, we challenged AML12 liver cells and mouse primary hepatocytes with palmitic acid (PA) with or without luteolin pretreatment. In the presence of PA, reactive oxygen species (ROS) production was increased at 3 h, followed by enhancement of expression of p-PERK, ATF4, p-eIF2α, CHOP, and TXNIP (ER stress markers) and p-p62 and LC3II/LC3I ratio (autophagy markers), in both primary hepatocytes and AML12 cells. When PA treatment was extended up to 24 h, apoptosis was induced as evidenced by an increase in caspase-3 activation. RFP-GFP-LC3B transfection further revealed that the fusion of autophagosomes with lysosomes was damaged by PA. With luteolin treatment, the expression of antioxidant enzymes, i.e., heme oxygenase-1 and glutathione peroxidase, was upregulated, and PA-induced ROS production, ER stress, and cell death were dose-dependently ameliorated. Luteolin could also reverse the damage caused to autophagic flux. These results indicate that luteolin protects hepatocytes against PA assault by enhancing antioxidant defense, which can attenuate ER stress and autophagy as well as promote autophagic flux.


Assuntos
Luteolina , Palmitatos , Camundongos , Animais , Luteolina/metabolismo , Antioxidantes/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Hepatócitos/metabolismo , Estresse do Retículo Endoplasmático , Ácido Palmítico/farmacologia , Autofagia , Apoptose
19.
J Dent Sci ; 18(2): 618-625, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37021222

RESUMO

Background/purpose: This is the first paper evaluating the efficacy of laser Doppler imager in diagnosis of pulpal vitality. The purpose of this study was to evaluate and compare the diagnostic benefits of laser Doppler imaging and electric pulp test (EPT) in dental trauma. Materials and methods: Seven patients were selected for pulp vitality evaluation in Kaohsiung Medical University Hospital between 2018 and 2019. EPT and laser Doppler imager evaluation were performed for patients with traumatic injury to teeth. Statistical methods included the Kappa consistency test and the chi-square test. In addition, the receiver operating characteristic (ROC) curve, and the area under the curve (AUC) were used. Results: There was a significant difference in Doppler flow values between the severe trauma group and the mild trauma group, regardless of patient self-reported symptoms (P = 0.043) or physicians' diagnostic classification (P = 0.018). For an EPT instrument, the Kappa coefficient was 0.67 and 1-year pulpal status findings were highly consistent (P < 0.001). Using a Doppler instrument, the Kappa coefficient was 0.85. According to the ROC curve, the AUC for EPT was 0.94, the AUC for Doppler was 1, and the optimal cut-off value was 31.55, indicating that both were superior diagnostic tools. Conclusion: Both laser Doppler imager and EPT can be used as tools for diagnosing traumatic pulp necrosis. Doppler imaging instruments allow for a more timely and accurate assessment of pulp vitality in dental trauma. In the future, ongoing research and related training are necessary for interpretation of Doppler data.

20.
J Cell Physiol ; 227(12): 3820-7, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22495818

RESUMO

MED28, a mammalian Mediator subunit, exhibits several cellular roles, including a merlin, Grb2, and cytoskeleton-associated protein (magicin), a repressor of smooth muscle cell differentiation, and an endothelial-derived gene (EG-1). Overexpression of MED28 may stimulate cell proliferation which presumably results from the transcriptional activation of the Mediator function. Additionally, several tumors, including breast cancer, highly express MED28. We have found recently that MED28 potentiated epidermal growth factor (EGF)-induced migration in human breast cancer cells. Therefore, the objective of this study is to identify the role of MED28 in the aspect of cellular migration and invasion in human breast cancer cells. Suppression of MED28 blocked cellular migration and invasion with concomitant reduced expression levels of matrix metalloproteinase-2 (MMP2) and mitogen-activated protein kinase kinase 1 (MAP2K1; MEK1); overexpression of MED28 enhanced cellular migration and upregulated MMP2 and MEK1 expression. Moreover, suppression of MEK1, by dominant-negative, kinase-dead MEK1 cDNA construct or MEK1-specific small interfering RNA (siRNA) as well as MEK1 inhibitors, blocked MED28-induced MMP2 activation, cellular migration, and invasion in breast cancer cells. Furthermore, ectopic expression of MEK1 rescued the inhibitory effect of MED28 knockdown on invasion, and exogenous MMP2 recombinant protein recovered the suppression on invasion upon MED28 or MEK1 knockdown. Our data indicate that MED28 regulates cellular migration in a MEK1-dependent manner in human breast cancer cells, reinforcing the important cellular roles of MED28.


Assuntos
Neoplasias da Mama/metabolismo , Movimento Celular/fisiologia , Regulação Neoplásica da Expressão Gênica/fisiologia , MAP Quinase Quinase 1/metabolismo , Complexo Mediador/metabolismo , Linhagem Celular Tumoral , DNA Complementar , Feminino , Técnicas de Silenciamento de Genes , Humanos , MAP Quinase Quinase 1/genética , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 2 da Matriz/metabolismo , Complexo Mediador/genética , Invasividade Neoplásica
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