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1.
Chem Biol Interact ; 334: 109354, 2021 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-33309620

RESUMO

Lactosyl-Sepharose binding proteins (LSBPs) were recently described in human pancreatic ductal adenocarcinoma (PDAC) Suit2-007 cells regarding their lectin-like properties and role in metastasis. This study further investigated how calcium and galactose influence the binding of LSBPs to the lactosyl resin as well as their anti-proliferative effect in Suit2-007 cells. Altered binding of LSBPs to the lactosyl resin was evaluated by affinity chromatography and mass spectrometry. Calcium binding EF-hand proteins were aligned and identified with a motif derived from the Uniprot protein database. The antiproliferative effects of LSBPs and monosaccharides were determined by MTT assay. In addition, LSBPs and galactose effects were investigated by chip array and tumor take in nude rats. LSBPs reduced Suit2-007 cells' proliferation with an IC50 of 125 µg/mL. Coincubation of LSBPs with EGTA decreased the number of LSBPs binding to the lactosyl resin by ~50%. Ca2+ -sensitive LSBPs included subgroups of galactose-sensitive (10%) and EF-hand calcium binding motifs containing (2.5%) proteins. In vitro, the combination of LSBPs with monosaccharides including galactose synergistically decreased cell proliferation compared to single agents (p < 0.05). In addition, LSBPs in combination with galactose prevented the tumor growth of Suit2-007 cells in nude rats, as opposed to single treatments. At mRNA level, the combination treatment modulated 5% of Ca2+ -sensitive LSBPs and downregulated 216 genes, 18% of which were up-regulated during PDAC progression. This study highlights the importance of calcium and galactose in modulating the affinity and anti-proliferative activity of LSBPs and their potential application as therapeutic agents for metastatic PDAC.


Assuntos
Proteínas de Ligação ao Cálcio/metabolismo , Cálcio/metabolismo , Proliferação de Células/fisiologia , Galactose/metabolismo , Ligação Proteica/fisiologia , Sefarose/metabolismo , Animais , Linhagem Celular Tumoral , Regulação para Baixo/fisiologia , Regulação Neoplásica da Expressão Gênica/fisiologia , Humanos , Lectinas/metabolismo , Masculino , RNA Mensageiro/metabolismo , Ratos , Ratos Nus , Regulação para Cima/fisiologia
2.
Nat Commun ; 11(1): 4902, 2020 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-32994402

RESUMO

Living cells and tissues experience various complex modes of forces that are important in physiology and disease. However, how different force modes impact gene expression is elusive. Here we apply local forces of different modes via a magnetic bead bound to the integrins on a cell and quantified cell stiffness, chromatin deformation, and DHFR (dihydrofolate reductase) gene transcription. In-plane stresses result in lower cell stiffness than out-of-plane stresses that lead to bead rolling along the cell long axis (i.e., alignment of actin stress fibers) or at different angles (90° or 45°). However, chromatin stretching and ensuing DHFR gene upregulation by the in-plane mode are similar to those induced by the 45° stress mode. Disrupting stress fibers abolishes differences in cell stiffness, chromatin stretching, and DHFR gene upregulation under different force modes and inhibiting myosin II decreases cell stiffness, chromatin deformation, and gene upregulation. Theoretical modeling using discrete anisotropic stress fibers recapitulates experimental results and reveals underlying mechanisms of force-mode dependence. Our findings suggest that forces impact biological responses of living cells such as gene transcription via previously underappreciated means.


Assuntos
Cromatina/química , Fibras de Estresse/química , Tetra-Hidrofolato Desidrogenase/genética , Transcrição Genética/fisiologia , Regulação para Cima/fisiologia , Animais , Anisotropia , Fenômenos Biomecânicos/genética , Células CHO , Cromatina/metabolismo , Cricetulus , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Microscopia Intravital , Microscopia de Fluorescência , Miosina Tipo II/antagonistas & inibidores , Miosina Tipo II/metabolismo , Fibras de Estresse/efeitos dos fármacos , Fibras de Estresse/metabolismo , Estresse Mecânico , Transcrição Genética/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos
3.
Life Sci ; 258: 118240, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32781072

RESUMO

As a dicarboxylic acid with the structural formula HOOCCH (OH) COOH, tartronic acid is considered as an inhibitor of the transformation of carbohydrates into fat under fat-deficient diet conditions. However, the effect of tartronic acid on lipogenesis under high-fat diet conditions has yet to be established. In this work, we investigated the regulatory role of tartronic acid in lipogenesis in 3T3-L1 adipocytes and C57BL/6J mice. The results confirmed that tartronic acid promoted weight gain (without affecting food intake) and induced adipocyte hypertrophy in epididymal white adipose tissue and lipid accumulation in the livers of high-fat diet-induced obese mice. In vitro, tartronic acid promoted 3T3-L1 adipocyte differentiation by increasing the protein expression of FABP-4, PPARγ and SREBP-1. Moreover, the contents of both acetyl-CoA and malonyl-CoA were significantly upregulated by treatment with tartronic acid, while the protein expression of CPT-1ß were inhibited. In summary, we proved that tartronic acid promotes lipogenesis by serving as substrates for fatty acid synthesis and inhibiting CPT-1ß, providing a new perspective for the study of tartronic acid.


Assuntos
Acetilcoenzima A/biossíntese , Carnitina O-Palmitoiltransferase/antagonistas & inibidores , Lipogênese/efeitos dos fármacos , Malonil Coenzima A/biossíntese , Tartronatos/farmacologia , Regulação para Cima/efeitos dos fármacos , Células 3T3-L1 , Animais , Carnitina O-Palmitoiltransferase/metabolismo , Dieta Hiperlipídica/efeitos adversos , Lipogênese/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Regulação para Cima/fisiologia
4.
Nat Cell Biol ; 22(9): 1116-1129, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32807903

RESUMO

How allelic asymmetry is generated remains a major unsolved problem in epigenetics. Here we model the problem using X-chromosome inactivation by developing "BioRBP", an enzymatic RNA-proteomic method that enables probing of low-abundance interactions and an allelic RNA-depletion and -tagging system. We identify messenger RNA-decapping enzyme 1A (DCP1A) as a key regulator of Tsix, a noncoding RNA implicated in allelic choice through X-chromosome pairing. DCP1A controls Tsix half-life and transcription elongation. Depleting DCP1A causes accumulation of X-X pairs and perturbs the transition to monoallelic Tsix expression required for Xist upregulation. While ablating DCP1A causes hyperpairing, forcing Tsix degradation resolves pairing and enables Xist upregulation. We link pairing to allelic partitioning of CCCTC-binding factor (CTCF) and show that tethering DCP1A to one Tsix allele is sufficient to drive monoallelic Xist expression. Thus, DCP1A flips a bistable switch for the mutually exclusive determination of active and inactive Xs.


Assuntos
Endorribonucleases/metabolismo , RNA/metabolismo , Transativadores/metabolismo , Cromossomo X/metabolismo , Alelos , Animais , Fator de Ligação a CCCTC/metabolismo , Linhagem Celular , Feminino , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , RNA Mensageiro/metabolismo , Transcrição Genética/fisiologia , Regulação para Cima/fisiologia , Inativação do Cromossomo X/fisiologia
6.
Sci Rep ; 10(1): 12238, 2020 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-32699266

RESUMO

Crohn's disease (CD) is a chronic inflammatory disorder characterized by immune response dysregulation. Tumor necrosis factor-α (TNFα) is a key cytokine in the pathogenesis of CD, as indicated by the efficacy of anti-TNF-α therapy with infliximab (IFX). However, approximately 30-40% of CD patients fail to respond to IFX with still unclear underlying mechanisms. This study compares the inflammatory phenotype of monocytes from CD patients, who respond or non-respond to IFX. Under basal conditions, the mRNA for the cytokines TNFα, IL-23, IL-1ß and the chemokines CXCL8/IL-8, CCL5/RANTES and CCL2/MCP-1 was up-regulated in monocytes from non-responders than responders. The expression of the same cytokines and CCL2/MCP-1 was higher in non-responders also upon LPS treatment. Moreover, higher secretion of TNFα, IL-1ß, IFNγ and IL-2 proteins occurred in the supernatants of LPS-treated non-responders cells. Resistance to IFX in CD may result from a transcriptional dysregulation of circulating monocytes, leading to hyperactivation of pro-inflammatory pathways. Monocytes' cytokine profile may thus represent a predictive marker of response to IFX. Monocytes were isolated from blood samples of 19 CD patients (11 responders, 8 non-responders) and incubated with or without LPS. Cytokine profiles were assessed by RT-qPCR and, in the supernatants, by ELISA assay.


Assuntos
Doença de Crohn/tratamento farmacológico , Doença de Crohn/metabolismo , Citocinas/metabolismo , Infliximab/uso terapêutico , Monócitos/metabolismo , Adulto , Idoso , Resistência a Medicamentos/efeitos dos fármacos , Resistência a Medicamentos/fisiologia , Feminino , Humanos , Inflamação/metabolismo , Masculino , Pessoa de Meia-Idade , Transcrição Genética/fisiologia , Regulação para Cima/fisiologia , Adulto Jovem
7.
Am J Respir Cell Mol Biol ; 63(4): 452-463, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32663413

RESUMO

Emphysema is a progressive and fatal lung disease with no cure that is characterized by thinning, enlargement, and destruction of alveoli, leading to impaired gas exchange. Disease progression is due in part to dysregulation of VEGF (vascular endothelial growth factor) signaling in the lungs and increased lung-cell apoptosis. Here we asked whether PR1P (Prominin-1-derived peptide), a novel short peptide we designed that increases VEGF binding to endothelial cells, could be used to improve outcome in in vitro and in vivo models of emphysema. We used computer simulation and in vitro and in vivo studies to show that PR1P upregulated endogenous VEGF receptor-2 signaling by binding VEGF and preventing its proteolytic degradation. In so doing, PR1P mitigated toxin-induced lung-cell apoptosis, including from cigarette-smoke extract in vitro and from LPS in vivo in mice. Remarkably, inhaled PR1P led to significantly increased VEGF concentrations in murine lungs within 30 minutes that remained greater than twofold above that of control animals 24 hours later. Finally, inhaled PR1P reduced acute lung injury in 4- and 21-day elastase-induced murine emphysema models. Taken together, these results highlight the potential of PR1P as a novel therapeutic agent for the treatment of emphysema or other lung diseases characterized by VEGF signaling dysregulation.


Assuntos
Elastase Pancreática/metabolismo , Peptídeos/metabolismo , Enfisema Pulmonar/metabolismo , Transdução de Sinais/fisiologia , Regulação para Cima/fisiologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Animais , Apoptose/fisiologia , Simulação por Computador , Modelos Animais de Doenças , Células Endoteliais/metabolismo , Feminino , Pulmão/metabolismo , Camundongos , Camundongos Endogâmicos C3H , Alvéolos Pulmonares/metabolismo , Fumaça/efeitos adversos , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo
8.
J Cancer Res Clin Oncol ; 146(9): 2241-2253, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32494918

RESUMO

PURPOSE: Bone metastasis is the result of complex crosstalk between tumor cells and bone marrow cells. Bone marrow adipocytes (BMAs) are the most abundant cell type in adult bone marrow. Therefore, we explore the effects of BMAs on bone metastasis in lung cancer. METHODS: RNA-seq was used to compare the mRNA expression level of bone metastatic SBC5 cells and non-bone metastatic SBC3 cells. Rosiglitazone-induced marrow adiposity and intra-femoral injection of SBC5 cells were used to demonstrate the relationship between BMAs and SBC5 cells in vivo. Co-culture system, gene co-expression, gene ontology (GO) enrichment analysis and protein-protein interaction (PPI) network were used to explore the potential mechanism. RESULTS: BMAs specially enhance the invasion of bone metastatic SBC5 instead of non-bone metastatic SBC3 in vitro. SBC5 instead of SBC3 promoted osteoblast and osteoclast differentiation as well as de-differentiation of mature BMAs. Rosiglitazone-induced marrow adiposity significantly enhanced osteolytic lesion induced by SBC5 in vivo. RNA-seq revealed that compared with SBC3, S100A9 and S100A8 genes were the most prominent genes up-regulated in SBC5 cells. High expression of S100A8/9 in SBC5 could be responsible for the crosstalk between lung cancer cells and BMAs. More importantly, interleukin 6 receptor (IL6R), which is adjacent to S100A8/A9 in 1q21.3, was significantly up-regulated by BMAs in vitro. S100A8/A9 (1 µg/ml) could obviously enhance the osteoblastic differentiation and inhibit adipogenic differentiation, whereas TLR4 inhibitor TAK242 (10 µmol/l) significantly attenuated this effect. CONCLUSIONS: Our study suggested that bone marrow adipocyte may communicate with lung cancer cells via 1q21.3 (S100A8/A9-IL6R)-TLR4 pathway to promote osteolytic bone destruction. 1q21.3 (S100A8/A9-IL6R) is a potential target for the treatment of lung cancer bone metastasis.


Assuntos
Adipócitos/metabolismo , Medula Óssea/metabolismo , Osso e Ossos/metabolismo , Neoplasias Pulmonares/metabolismo , Osteólise/metabolismo , Receptores de Interleucina-6/metabolismo , Proteínas S100/metabolismo , Receptor 4 Toll-Like/metabolismo , Animais , Células da Medula Óssea/metabolismo , Linhagem Celular Tumoral , Técnicas de Cocultura/métodos , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Osteoblastos/metabolismo , Transdução de Sinais/fisiologia , Regulação para Cima/fisiologia
9.
Sci Rep ; 10(1): 10180, 2020 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-32576895

RESUMO

CD47 deficient mice are resistant to dextran sulfate sodium (DSS)-induced experimental colitis. The underlying mechanism, however, remains incompletely understood. In this study, we characterized the role of CD47 in modulating homeostasis of gastrointestinal tract. We found that CD47 expression in both human and mouse intestinal epithelium was upregulated in colitic condition compared to that under normal condition. In line with this, CD47 deficiency protected mice from DSS-induced colitis. Analysis based on both intestinal organoid and cultured cell assays showed that CD47 deficiency accelerated intestinal epithelial cell proliferation and migration. Mechanistically, western blot and functional assays indicated that CD47 deficiency promoting mouse intestinal epithelial cell proliferation and migration follow cell injury is likely through upregulating expression of four Yamanaka transcriptional factors Oct4, Sox2, Klf4 and c-Myc (OSKM in abbreviation). Our studies thus reveal CD47 as a negative regulator in intestinal epithelial cell renewal during colitis through downregulating OSKM transcriptional factors.


Assuntos
Antígeno CD47/metabolismo , Autorrenovação Celular/fisiologia , Colite/metabolismo , Células Epiteliais/metabolismo , Mucosa Intestinal/metabolismo , Intestinos/fisiologia , Animais , Apoptose/fisiologia , Linhagem Celular Tumoral , Proliferação de Células/fisiologia , Células Cultivadas , Colite/induzido quimicamente , Sulfato de Dextrana/farmacologia , Modelos Animais de Doenças , Células Epiteliais/efeitos dos fármacos , Células HT29 , Homeostase/fisiologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Transdução de Sinais/fisiologia , Regulação para Cima/fisiologia
10.
Adv Clin Exp Med ; 29(5): 565-572, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32421262

RESUMO

BACKGROUND: Thoracic aortic aneurysm (TAA) formation is accompanied by degradation of extracellular matrix components (EMC). Numerous matrix metalloproteinases (MMPs) have been implicated in the process, but the involvement of MMP-3 remains unclear. Additionally, the changes in proteoglycan (PG) structure can alter the signal transduction pathways in TAA, though the enzymatic systems which originate them are not fully understood. OBJECTIVES: To measure MMP-3 and sulfatase levels in aneurysmal tissue, comparing them with non-aneurysmal vessels, and to investigate possible correlations with patients' serum levels in order to evaluate their potential usefulness in aiding aneurysm detection and monitoring. MATERIAL AND METHODS: The study included 74 patients (TAA: n = 42; control group: n = 32). Sulfatase activity was measured colometrically and MMP-3 levels were measured immunoenzymatically. RESULTS: Sulfatase activities were higher (p = 0.03) and MMP-3 concentrations lower (p = 0.014) in aneurysmal tissue than in normal aortic tissue. Medium-sized dilatations were associated with lower tissue MMP-3 concentrations than small dilatations (p = 0.033). No differences in sulfatase activity or MMP-3 concentration in the serum of TAA patients were observed in comparison with the controls. The serum and tissue levels of MMP-3 were correlated (r = 0.41; p < 0.001). The serum levels of MMP-3 were significantly lower in the female patients than in the male patients (p = 0.006). CONCLUSIONS: Our studies confirmed the lower MMP-3 levels in aneurysmal tissue, but the lack of a statistically confirmed reduction of MMP-3 in the blood serum seems to preclude its usefulness for diagnostic purposes. Our study points to the differences in MMP-3 behavior between TAA and abdominal aortic aneurysms. Significantly higher sulfatase activity in TAA tissue suggests a possible impact of sulfatase on signal transduction pathways involved in aneurysm formation.


Assuntos
Aneurisma da Aorta Torácica/diagnóstico , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 3 da Matriz/metabolismo , Sulfatases/metabolismo , Aorta , Aorta Torácica , Aneurisma da Aorta Torácica/sangue , Estudos de Casos e Controles , Regulação para Baixo/fisiologia , Feminino , Humanos , Masculino , Sulfatases/genética , Regulação para Cima/fisiologia
11.
Invest Ophthalmol Vis Sci ; 61(5): 10, 2020 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-32396631

RESUMO

Purpose: A burst in phagocytosis of spent photoreceptor outer fragments by RPE is a rhythmic process occurring 1 to 2 hours after the onset of light. This phenomenon is considered crucial for the health of the photoreceptors and RPE. We have recently reported that dopamine, via dopamine 2 receptor (D2R), shifts the circadian rhythm in the RPE. Methods: Here, we first investigated the impact of the removal of D2R on the daily peak of phagocytosis by RPE and then we analyzed the function and morphology of retina and RPE in the absence of D2R. Results: D2R knockout (KO) mice do not show a daily burst of phagocytic activity after the onset of light. RNA sequencing revealed a total of 394 differentially expressed genes (DEGs) between ZT 23 and ZT 1 in the control mice, whereas in D2R KO mice, we detected 1054 DEGs. Pathway analysis of the gene expression data implicated integrin signaling to be one of the upregulated pathways in control but not in D2R KO mice. Consistent with the gene expression data, phosphorylation of focal adhesion kinase (FAK) did not increase significantly in KO mice at ZT 1. No difference in retinal thickness, visual function, or morphology of RPE cells was observed between wild-type (WT) and D2R KO mice at the age of 3 and 12 months. Conclusions: Our data suggest that removal of D2R prevents the burst of phagocytosis and a related increase in the phosphorylation of FAK after light onset. The pathway analysis points toward a putative role of D2R in controlling integrin signaling, which is known to play an important role in the control of the daily burst of phagocytosis by the RPE. Our data also indicate that the absence of the burst of phagocytic activity in the early morning does not produce any apparent deleterious effect on the retina or RPE up to 1 year of age.


Assuntos
Fagocitose , Receptores de Dopamina D2/fisiologia , Epitélio Pigmentado da Retina/patologia , Transdução de Sinais/fisiologia , Animais , Proteína-Tirosina Quinases de Adesão Focal/metabolismo , Integrinas/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fagossomos/patologia , Fosforilação/fisiologia , Tomografia de Coerência Óptica , Regulação para Cima/fisiologia
12.
Medicine (Baltimore) ; 99(19): e20183, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32384511

RESUMO

BACKGROUNDS: Lung adenocarcinoma (LUAD) is one of the most common malignancies, and is a serious threat to human health. The aim of the present study was to assess potential biomarkers for the prognosis of LUAD through the analysis of gene expression microarrays. METHODS: The gene expression data for GSE118370 was downloaded from the Gene Expression Omnibus (GEO) database. Differentially expressed genes (DEGs) between normal lung and LUAD samples were screened using the R language. The DAVID database was used to analyze the functions and pathways of DEGs. The STRING database was used to the map protein-protein interaction (PPI) networks, and these were visualized with the Cytoscape software. Finally, the prognostic analysis of the hub gene in the PPI network was performed using the Kaplan-Meier tool. RESULTS: A total of 406 downregulated and 203 upregulated DEGs were identified. The GO analysis results revealed that downregulated DEGs were significantly enriched in angiogenesis, calcium ion binding and cell adhesion. The upregulated DEGs were significantly enriched in the extracellular matrix disassembly, collagen catabolic process, chemokine-mediated signaling pathway and endopeptidase inhibitor activity. The KEGG pathway analysis revealed that downregulated DEGs were enriched in neuroactive ligand-receptor interaction, hematopoietic cell lineage and vascular smooth muscle contraction, while upregulated DEGs were enriched in phototransduction. In addition, the top 10 hub genes and the most closely interacting modules of the top 3 proteins in the PPI network were screened. Finally, the independent prognostic value of each hub gene in LUAD patients was analyzed through the Kaplan-Meier plotter. Seven hub genes (ADCY4, S1PR1, FPR2, PPBP, NMU, PF4, and GCG) were closely correlated to overall survival time. CONCLUSION: The discovery of these candidate genes and pathways reveals the etiology and molecular mechanisms of LUAD, providing ideas and guidance for the development of new therapeutic approaches to LUAD.


Assuntos
Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/mortalidade , Bases de Dados Genéticas , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/mortalidade , Biomarcadores Tumorais , Quimiocinas/metabolismo , Colágeno/metabolismo , Regulação para Baixo/fisiologia , Matriz Extracelular/metabolismo , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Ontologia Genética , Humanos , Estimativa de Kaplan-Meier , Análise em Microsséries , Prognóstico , Inibidores de Proteases/metabolismo , Mapas de Interação de Proteínas , Regulação para Cima/fisiologia
13.
Cancer Immunol Immunother ; 69(9): 1891-1903, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32377817

RESUMO

The objective response rate of immune checkpoint blockade (ICB) in hepatocellular carcinoma (HCC) with anti PD-L1/PD-1 therapy is low. Discovering the signaling pathways regulating PD-L1 might help to improve ICB response rates. Here, we investigate transcription factors IRF-1 and IRF-2 signaling pathways regulating PD-L1 in HCC cells. In vivo studies show that IRF-1 and PD-L1 mRNA expression in human HCC tumors are significantly repressed compared with noncancerous background liver. IRF-1, IRF-2, and PD-L1 mRNA expression correlated positively in HCC tumors. Increased IRF-1 mRNA expression was observed in patients with well-differentiated or early stage HCC tumors. In vitro studies show that IFN-γ induces PD-L1 mRNA and protein expression through upregulation of IRF-1 in mouse and human HCC cells. IRF-1, IRF-2, and PD-L1 mRNA expression is upregulated in murine HCC by co-culture with effector T cells from spleen cells incubated with anti-CD3/CD28 antibodies. IRF-2 over-expression down-regulates IFN-γ induced PD-L1 promoter activity and protein levels in a dose-dependent manner. We identify two IRF-1 response elements (IRE1/IRE2) in the upstream 5'-flanking region of the CD274 (PD-L1) gene promoter. Site-directed mutagenesis shows both IRE1 and IRE2 are functional in transfection promoter assays. IRF-1 traditionally functions as tumor suppressor gene. However, these novel findings show a complex role for IRF-1 which upregulates PD-L1 in the inflammatory tumor microenvironment. IRF-1 antagonizes IRF-2 for binding to the IRE promoter element in PD-L1 which gives new insight to the regulation of PD-L1/PD-1 pathways in HCC ICB therapy.


Assuntos
Antígeno B7-H1/metabolismo , Carcinoma Hepatocelular/metabolismo , Fator Regulador 1 de Interferon/metabolismo , Fator Regulador 2 de Interferon/metabolismo , Neoplasias Hepáticas/metabolismo , Idoso , Animais , Linhagem Celular Tumoral , Regulação para Baixo/fisiologia , Feminino , Células Hep G2 , Humanos , Interferon gama/metabolismo , Masculino , Camundongos , Transdução de Sinais/fisiologia , Microambiente Tumoral/fisiologia , Regulação para Cima/fisiologia
14.
Metabolism ; 108: 154261, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32407726

RESUMO

BACKGROUND: Fibronectin type IIIdomain-containing protein 4 (FNDC4) constitutes a secreted factor showing a high homology in the fibronectin type III and transmembrane domains with the exercise-associated myokine irisin (FNDC5). We sought to evaluate whether FNDC4 mimics the anti-obesity effects of FNDC5/irisin in human adipose tissue. METHODS: Plasma and adipose tissue samples of 78 patients with morbid obesity undergoing bariatric surgery and 26 normal-weight individuals were used in the present study. RESULTS: Plasma FNDC4 was decreased in patients with morbid obesity, related to obesity-associated systemic inflammation and remained unchanged six months after bariatric surgery. Visceral adipose tissue from patients with morbid obesity showed higher expression of FNDC4 and its putative receptor GPR116 regardless of the degree of insulin resistance. FNDC4 content was regulated by lipogenic, lipolytic and proinflammatory stimuli in human visceral adipocytes. FNDC4 reduced intracytosolic lipid accumulation and stimulated a brown-like pattern in human adipocytes, as evidenced by an upregulated expression of UCP-1 and the brown/beige adipocyte markers PRDM16, TMEM26 and CD137. Moreover, FNDC4 treatment upregulated mitochondrial DNA content and factors involved in mitochondrial biogenesis (TFAM, NRF1 and NRF2). Human FNDC4-knockdown adipocytes exhibited an increase in lipogenesis and a reduction of brown/beige-specific fat markers as well as factors involved in mitochondrial biogenesis. CONCLUSIONS: Taken together, the novel adipokine FNDC4 reduces lipogenesis and increases fat browning in human visceral adipocytes. The upregulation of FNDC4 in human visceral fat might constitute an attempt to attenuate the adipocyte hypertrophy, inflammation and impaired beige adipogenesis in the obese state.


Assuntos
Adipócitos/metabolismo , Adipocinas/metabolismo , Tecido Adiposo Marrom/metabolismo , Lipogênese/fisiologia , Proteínas/metabolismo , Adipócitos Bege/metabolismo , Células Cultivadas , Estudos Transversais , Feminino , Humanos , Inflamação/metabolismo , Resistência à Insulina/fisiologia , Gordura Intra-Abdominal/metabolismo , Masculino , Pessoa de Meia-Idade , Mitocôndrias/metabolismo , Obesidade/metabolismo , Receptores Acoplados a Proteínas-G/metabolismo , Proteína Desacopladora 1/metabolismo , Regulação para Cima/fisiologia
15.
Metabolism ; 108: 154258, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32376130

RESUMO

RATIONALE: Tubulointerstitial fibrosis, which is closely related to functional injury of the kidney, can be observed in advanced stages of diabetic nephropathy (DN). Mammalian serine/threonine-protein kinase 4 (MST1), a core component of the Hippo pathway that is involved in cellular proliferation and differentiation, plays a crucial role in the pathogenesis of multiple metabolic diseases, kidney diseases and cancer. METHODS: In type 1 and type 2 diabetic animals, as well as in human proximal tubular epithelial cells (HK-2), activation of MST1 was analyzed by immunohistochemistry and western blotting. In db/db mice, MST1 protein was knocked down or overexpressed by shRNA, and renal function, fibrosis, and downstream signaling were then investigated. RNA silencing and overexpression were performed by using an MST1 or YAP knockdown/expression lentivirus to investigate the regulation of MST1-mediated YAP/TEAD signaling pathways in the fibrosis process in HK-2 cells. Luciferase and coimmunoprecipitation (co-IP) assays were used to identify whether YAP directly regulated TEAD activation by forming a YAP-TEAD heterodimer, which ultimately leads to tubulointerstitial fibrosis. RESULTS: MST1 activation was significantly decreased in type 1 and type 2 diabetic nephropathy. Notably, the downregulation of MST1 activation was also observed in HK-2 cells in a glucose- and time-dependent manner. In vivo, downregulation of MST1 was sufficient to promote renal dysfunction and fibrosis in db/m mice, whereas overexpression of MST1 ameliorated diabetic nephropathy-induced renal fibrosis. Further mechanistic study demonstrated that activated YAP induced by MST1 inhibition directly upregulated TEAD activation by binding to TEAD and forming a YAP-TEAD heterodimer, resulting in the promotion of epithelial-mesenchymal transition (EMT) and fibrosis in renal tubular epithelial. CONCLUSIONS: MST1 activation represents a potential therapeutic strategy to treat or prevent the progression of diabetic nephropathy-induced renal fibrosis.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas de Ciclo Celular/metabolismo , Diabetes Mellitus/metabolismo , Nefropatias Diabéticas/metabolismo , Transição Epitelial-Mesenquimal/fisiologia , Fibrose/metabolismo , Nefropatias/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Animais , Regulação para Baixo/fisiologia , Regulação da Expressão Gênica/fisiologia , Glucose/metabolismo , Túbulos Renais/metabolismo , Camundongos , Ratos , Transdução de Sinais/fisiologia , Fatores de Transcrição/metabolismo , Regulação para Cima/fisiologia
16.
PLoS One ; 15(4): e0232230, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32340025

RESUMO

BACKGROUND: Proinflammatory interleukin-33 (IL-33) binds to its receptor ST2L and is involved in inflammation and the malignant behavior of cancer cells. However, the role of IL-33-ST2L and the IL-33 decoy receptor sST2 in the tumor microenvironment of pancreatic cancer is unclear. Because we previously reported that sST2 derived from colon cancer cells profoundly influences malignant tumor growth, we hypothesized that sST2 released from pancreatic cancer cells also modulates IL-33-ST2L signaling in the tumor microenvironment, thereby influencing tumor growth. METHODS: ST2 (ST2L and sST2) expression in mouse pancreatic cancer Panc02 cells was downregulated by shRNAs. mRNA expression levels of IL-33, ST2, cytokines and chemokines in the cells and tumor tissues were examined using real-time PCR. sST2 secretion and the amount of CXCL3 in tumor tissues were measured using ELISA. Tumor growth was investigated after injection of the cells into the pancreas of C57BL/6 mice. MPO+, F4/80+ and CD20+ cells in tumor tissues were detected using immunohistochemistry. RESULTS: Some but not all human and mouse pancreatic cancer cell lines preferentially expressed sST2. Then, we investigated the role of sST2 in orthotopic tumor growth of sST2-expressing mouse pancreatic cancer Panc02 cells in immunocompetent mice. shRNA-mediated knockdown of sST2 expression in the cells suppressed orthotopic tumor growth, which was partially recovered by overexpression of shRNA-resistant sST2 mRNA but was not evident in IL-33 knockout mice. This was associated with decreases in Cxcl3 expression, vessel density and accumulation of cancer-associated neutrophils but not cancer-associated macrophages. Administration of SB225002, an inhibitor of the CXCL3 receptor CXCR2, induced similar effects. CONCLUSIONS: Cancer cell-derived sST2 enhances tumor growth through upregulation of CXCL3 via inhibition of IL-33-ST2L signaling in the tumor microenvironment of pancreatic cancer. These results suggest that the sST2 and the CXCL3-CXCR2 axis could be therapeutic targets.


Assuntos
Proliferação de Células/fisiologia , Proteína 1 Semelhante a Receptor de Interleucina-1/metabolismo , Interleucina-33/metabolismo , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Animais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Humanos , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Células PC-3 , Pâncreas/metabolismo , Pâncreas/patologia , Receptores de Interleucina-1/metabolismo , Transdução de Sinais/fisiologia , Microambiente Tumoral/fisiologia , Regulação para Cima/fisiologia
17.
Arch Biochem Biophys ; 687: 108385, 2020 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-32335050

RESUMO

MicroRNA-342-3p (miR-342) has been shown to act as a tumor-suppressor in different cancer types. However, the role and therapeutic implications of miR-342 via modulation of Cofilin 1 (CFL1) has not been studied in any type of cancer. Given the importance of Cofilin signalling in breast, this study was undertaken to explore the therapeutic implications of miR-342 and its target CFL1 in breast cancer. Herein, we found that miR-342 was significantly (P < 0.05) downregulated in breast cancer tissues and cell lines. Functional assays revealed that overexpression of miR-342 caused a significant (P < 0.05) inhibition of the proliferation, colony formation, invasion and migration of the MDA-MB-436 and CAMA-1 breast cancer cells via induction of apoptosis. Bioinformatic approaches and the dual luciferase reporter assay confirmed the interaction between miR-342 and its target CFL1. Moreover, we found that CFL1 was aberrantly overexpressed in breast cancer tissues and cell lines. Overexpression of miR-342 caused remarkable depletion in the expression of CFL1 in MDA-MB-436 breast cancer cells. Silencing of CFL1 in CAMA-1 and MDA-MB-436 cells caused remarkable decrease in the proliferation, colony formation and migration of these cells, similar to that of miR-342 ovexpression. However, overexpression of CFL1 in MDA-MB-346 cells could avoid the tumor suppressive effects of miR-342. Our data provide novel information about the implications of miR-342 and its target CFL1 in breast cancer treatment.


Assuntos
Neoplasias da Mama/fisiopatologia , Movimento Celular/fisiologia , Proliferação de Células/fisiologia , Cofilina 1/metabolismo , MicroRNAs/metabolismo , Adulto , Idoso , Apoptose/fisiologia , Linhagem Celular Tumoral , Regulação para Baixo/fisiologia , Regulação Neoplásica da Expressão Gênica/fisiologia , Humanos , Pessoa de Meia-Idade , Regulação para Cima/fisiologia
18.
Sci Rep ; 10(1): 5819, 2020 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-32242034

RESUMO

Climatic change is pointed as one of the major challenges for global food security. Based on current models of climate change, reduction in precipitations and in turn, increase in the soil salinity will be a sharp constraint for crops productivity worldwide. In this context, root fungi appear as a new strategy to improve plant ecophysiological performance and crop yield under abiotic stress. In this study, we evaluated the impact of the two fungal endophytes Penicillium brevicompactum and P. chrysogenum isolated from Antarctic plants on nutrients and Na+ contents, net photosynthesis, water use efficiency, yield and survival in tomato and lettuce, facing salinity stress conditions. Inoculation of plant roots with fungal endophytes resulted in greater fresh and dry biomass production, and an enhanced survival rate under salt conditions. Inoculation of plants with the fungal endophytes was related with a higher up/down-regulation of ion homeostasis by enhanced expression of the NHX1 gene. The two endophytes diminished the effects of salt stress in tomato and lettuce, provoked a higher efficiency in photosynthetic energy production and an improved sequestration of Na+ in vacuoles is suggested by the upregulating of the expression of vacuolar NHX1 Na+/H+ antiporters. Promoting plant-beneficial interactions with root symbionts appears to be an environmentally friendly strategy to mitigate the impact of climate change variables on crop production.


Assuntos
Produtos Agrícolas/metabolismo , Produtos Agrícolas/fisiologia , Endófitos/fisiologia , Raízes de Plantas/metabolismo , Raízes de Plantas/fisiologia , Estresse Salino/fisiologia , Sódio/metabolismo , Regiões Antárticas , Biomassa , Mudança Climática , Produtos Agrícolas/microbiologia , Regulação para Baixo/fisiologia , Homeostase/fisiologia , Íons/metabolismo , Alface/metabolismo , Alface/microbiologia , Alface/fisiologia , Lycopersicon esculentum/metabolismo , Lycopersicon esculentum/microbiologia , Lycopersicon esculentum/fisiologia , Penicillium chrysogenum/fisiologia , Fotossíntese/fisiologia , Raízes de Plantas/microbiologia , Salinidade , Trocadores de Sódio-Hidrogênio/metabolismo , Solo , Estresse Fisiológico/fisiologia , Taxa de Sobrevida , Regulação para Cima/fisiologia , Água/metabolismo
19.
Biomed Res Int ; 2020: 8587458, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32185221

RESUMO

Oral squamous cell carcinoma, one of the most prevalent cancer types in the world, has been confirmed under the influence of a key circadian gene, PER2, whose role has been identified in the development of some other types of cancers. However, the mechanism through which PER2 regulates the progress of OSCC remains largely unknown. In this study, we showed that besides the abnormal expression and subcellular localization of PER2 observed in OSCC tissues and cells as expected, these anomalous changes also existed in the adjacent noncancerous tissues, which was a novel finding in our research. The phase of PER2 rhythmic expression pattern in OSCC cells was later than that in oral keratinocytes in the protein level. In addition, we demonstrated that PER2 played as a resistant factor in the development of OSCC by upregulating TP53 and inhibiting epithelial-mesenchymal transition in vitro and in vivo. Taken together, our results identified that the development of OSCC is closely associated with PER2, the aberrant expression and subcellular localization of which facilitates the malignant progress.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Neoplasias Bucais/metabolismo , Proteínas Circadianas Period/metabolismo , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Progressão da Doença , Transição Epitelial-Mesenquimal/fisiologia , Feminino , Regulação Neoplásica da Expressão Gênica/fisiologia , Humanos , Queratinócitos/metabolismo , Queratinócitos/patologia , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/patologia , Regulação para Cima/fisiologia
20.
Invest Ophthalmol Vis Sci ; 61(3): 6, 2020 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-32150248

RESUMO

Purpose: We performed a bioinformatic transcriptome analysis to determine the alteration of gene expression between the native retina and retinal organoids in both mice and humans. Methods: The datasets of mouse native retina (GSE101986), mouse retinal organoids (GSE102794), human native retina (GSE104827), and human retinal organoids (GSE119320) were obtained from Gene Expression Omnibus. After normalization, a principal component analysis was performed to categorize the samples. The genes were clustered to classify them. A functional analysis was performed using the bioinformatics tool Gene ontology enrichment to analyze the biological processes of selected genes and cellular components. Results: The development of retinal organoids is slower than that in the native retina. In the early stage, cell proliferation predominates. Subsequently, neural differentiation is dominant. In the later stage, the dominant differentiated cells are photoreceptors. Additionally, the fatty acid metabolic process and mitochondria-related genes are upregulated over time, and the glycogen catabolic process and activin receptors are gradually downregulated in human retinal organoids. However, these trends are opposite in mouse retinal organoids. There are two peaks in mitochondria-related genes, one in the early development period and another during the photoreceptor development period. It takes about five times longer for human retinal development to achieve similar levels of mouse retinal development. Conclusions: Our study reveals the similarities and differences in the developmental features of retinal organoids as well as the corresponding relationship between mouse and human retinal development.


Assuntos
Organoides/metabolismo , Retina/metabolismo , Animais , Técnicas de Cultura de Células/métodos , Diferenciação Celular/genética , Diferenciação Celular/fisiologia , Proliferação de Células/genética , Análise por Conglomerados , Biologia Computacional/métodos , Bases de Dados Genéticas , Ácidos Graxos/metabolismo , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica/fisiologia , Glicogênio/metabolismo , Humanos , Mitocôndrias/metabolismo , Domínios e Motivos de Interação entre Proteínas , Retina/citologia , Especificidade da Espécie , Transcriptoma , Regulação para Cima/fisiologia
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