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1.
J Biomed Sci ; 29(1): 69, 2022 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-36100865

RESUMO

The tripartite motif (TRIM) protein family is a highly conserved group of E3 ligases with 77 members known in the human, most of which consist of a RING-finger domain, one or two B-box domains, and a coiled-coil domain. Generally, TRIM proteins function as E3 ligases to facilitate specific proteasomal degradation of target proteins. In addition, E3 ligase independent functions of TRIM protein were also reported. In hepatocellular carcinoma, expressions of TRIM proteins are both regulated by genetic and epigenetic mechanisms. TRIM proteins regulate multiple biological activities and signaling cascades. And TRIM proteins influence hallmarks of HCC. This review systematically demonstrates the versatile roles of TRIM proteins in HCC and helps us better understand the molecular mechanism of the development and progression of HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Carcinoma Hepatocelular/genética , Humanos , Neoplasias Hepáticas/genética , Proteínas , Proteínas com Motivo Tripartido/genética , Proteínas com Motivo Tripartido/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
2.
Biochem Biophys Res Commun ; 521(4): 984-990, 2020 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-31727371

RESUMO

Diabetic nephropathy (DN) is among the common complications of diabetes and is a major cause of end-stage kidney disease. Emerging data indicate that renal inflammation is involved in DN progression and aggravation. Still, the exact cellular mechanisms remain unclear. Dysregulated expression of microRNAs (miRNAs) is associated with multiple diseases, including DN. The relationship between miRNAs and inflammation in DN is also unexplored. Here, we evaluated the role of miR-485 in mediating the response of human mesangial cells (HMCs) to a high glucose (HG) concentration, and the potential underlying mechanism. We found that miR-485 expression is significantly decreased in HG-stimulated HMCs. Overexpression of miR-485 suppressed HG-induced proliferation of HMCs. Lower production of proinflammatory cytokines (i.e., TNF-α, IL-1ß, and IL-6) was observed in miR-485-overexpressing HMCs. Overexpression of miR-485 markedly suppressed the overexpression of extracellular-matrix proteins, e.g., collagen IV (Col IV) and fibronectin (FN), in HG-stimulated HMCs. Furthermore, miR-485 suppressed the expression of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase 5 (NOX5), restrained the HG-induced HMC proliferation, downregulated the expression of proinflammatory cytokines, and inhibited the production of extracellular-matrix proteins in HMCs. These results provide new insights into the involvement of the miR-485-NOX5 signaling pathway in DN progression.


Assuntos
Nefropatias Diabéticas/genética , Inflamação/genética , Inflamação/patologia , Células Mesangiais/metabolismo , Células Mesangiais/patologia , MicroRNAs/metabolismo , Modelos Biológicos , NADPH Oxidase 5/metabolismo , Sequência de Bases , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Nefropatias Diabéticas/patologia , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/genética , Matriz Extracelular/efeitos dos fármacos , Matriz Extracelular/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Glucose/toxicidade , Células HEK293 , Humanos , Células Mesangiais/efeitos dos fármacos , MicroRNAs/genética , Estresse Oxidativo/efeitos dos fármacos
3.
Proc Natl Acad Sci U S A ; 114(41): E8685-E8694, 2017 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-28973887

RESUMO

The molecular underpinnings of invasion, a hallmark of cancer, have been defined in terms of individual mediators but crucial interactions between these mediators remain undefined. In xenograft models and patient specimens, we identified a c-Met/ß1 integrin complex that formed during significant invasive oncologic processes: breast cancer metastases and glioblastoma invasive resistance to antiangiogenic VEGF neutralizing antibody, bevacizumab. Inducing c-Met/ß1 complex formation through an engineered inducible heterodimerization system promoted features crucial to overcoming stressors during metastases or antiangiogenic therapy: migration in the primary site, survival under hypoxia, and extravasation out of circulation. c-Met/ß1 complex formation was up-regulated by hypoxia, while VEGF binding VEGFR2 sequestered c-Met and ß1 integrin, preventing their binding. Complex formation promoted ligand-independent receptor activation, with integrin-linked kinase phosphorylating c-Met and crystallography revealing the c-Met/ß1 complex to maintain the high-affinity ß1 integrin conformation. Site-directed mutagenesis verified the necessity for c-Met/ß1 binding of amino acids predicted by crystallography to mediate their extracellular interaction. Far-Western blotting and sequential immunoprecipitation revealed that c-Met displaced α5 integrin from ß1 integrin, creating a complex with much greater affinity for fibronectin (FN) than α5ß1. Thus, tumor cells adapt to microenvironmental stressors induced by metastases or bevacizumab by coopting receptors, which normally promote both cell migration modes: chemotaxis, movement toward concentrations of environmental chemoattractants, and haptotaxis, movement controlled by the relative strengths of peripheral adhesions. Tumor cells then redirect these receptors away from their conventional binding partners, forming a powerful structural c-Met/ß1 complex whose ligand-independent cross-activation and robust affinity for FN drive invasive oncologic processes.


Assuntos
Neoplasias da Mama/secundário , Resistencia a Medicamentos Antineoplásicos , Glioblastoma/secundário , Integrina beta1/metabolismo , Proteínas Proto-Oncogênicas c-met/metabolismo , Inibidores da Angiogênese/farmacologia , Animais , Apoptose/efeitos dos fármacos , Bevacizumab/farmacologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Adesão Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Feminino , Fibronectinas/metabolismo , Glioblastoma/tratamento farmacológico , Glioblastoma/metabolismo , Humanos , Integrina beta1/genética , Camundongos , Invasividade Neoplásica , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-met/genética , Transdução de Sinais/efeitos dos fármacos , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
4.
Biochem Biophys Res Commun ; 503(2): 977-983, 2018 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-29932921

RESUMO

Emerging evidence has shown that microRNAs (miRNAs) play a mediatory role in the pathogenesis of diabetic nephropathy (DN), but the function of the involved miRNAs is still incomplete. Here, we found that miR-455-3p was down-regulated in the human mesangial cells (HMC) and human proximal tubule epithelial cells (HK-2) stimulated with high glucose (HG) or transforming growth factor beta 1 (TGF-ß1). Rho-associated coiled coil-containing protein kinase 2 (ROCK2) was identified as a directed target of miR-455-3p. Overexpression of ROCK2 significantly attenuated the inhibitory effects of miR-455-3p on cell proliferation, extracellular matrix (ECM) synthesis and epithelial-mesenchymal transition (EMT) in HG-treated cells. Furthermore, the DN model was prepared by using high-fat feeding combined with Streptozotocin (STZ) induced rats, and the DN group was treated by injecting miR-455-3p agomir. The results of periodic acid-Schiff (PAS) and Masson staining showed that miR-455-3p overexpression improved the pathological changes of glomerular hypertrophy, mesangial amplification, and renal fibrosis. Additionally, miR-455-3p overexpression decreased ROCK2, proliferating cell nuclear antigen (PCNA) and Collagen I levels, and also reduced inflammatory cytokines TNF-α, MCP-1 and IL-1ß levels in vivo. Altogether, these results suggest that miR-455-3p plays an essential role in the treatment of renal fibrosis through repressing ROCK2 expression; and miR-455-3p might be an effective therapy for DN.


Assuntos
Nefropatias Diabéticas/genética , Regulação para Baixo , Rim/patologia , MicroRNAs/genética , Quinases Associadas a rho/genética , Animais , Linhagem Celular , Proliferação de Células , Nefropatias Diabéticas/patologia , Nefropatias Diabéticas/terapia , Transição Epitelial-Mesenquimal , Fibrose , Terapia Genética , Humanos , Masculino , Ratos Sprague-Dawley , Regulação para Cima
5.
Cell Physiol Biochem ; 42(2): 594-602, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28954270

RESUMO

BACKGROUND/AIMS: The diagnosis of type 2 diabetic nephropathy (T2DN) patients is important to prevent the long-term damaging effects of kidney loss in patients with diabetes and is decisive for patient outcomes. The aim of this study was to explore urine retinol binding protein (RBP) and neutrophil gelatinase-associated lipocalin (NGAL) in T2DN patients with and without albuminuria. METHODS: A total of 293 T2DN patients were divided into three groups according to their urine albumin/urine creatinine ratio (UACR): normoalbuminuria group (UACR<30 mg/g, n=100), microalbuminuria group (UACR 30-300 mg/g, n=100) and macroalbuminuria group (UACR>300 mg/g, n=93); 50 non-diabetic subjects were recruited as the control group. The levels of urine RBP, NGAL, TNF-α and IL-18 in T2DN patients and non-diabetic subjects were measured using ELISA assays. RESULTS: We first analyzed the clinical characteristics of the control and T2DN groups and found that urine NGAL, RBP, TNF-α and IL-18 levels were significantly increased and significantly correlated with the degree of albuminuria. In addition, univariate linear regression analysis showed that urine RBP was associated with UACR, BMI, Scr, BUN, TG, disease duration, SBP, NGAL, TNF-α and IL-18 levels, and urine NGAL was positively correlated with UACR, Scr, BUN, RBP, TNF-α and IL-18 levels. CONCLUSION: The results indicate that urine levels of NGAL and RBP may be independently associated with albuminuria in T2DN and may serve as novel biomarkers for the identification of T2DN.


Assuntos
Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/urina , Nefropatias Diabéticas/complicações , Nefropatias Diabéticas/urina , Lipocalina-2/urina , Proteínas de Ligação ao Retinol/urina , Idoso , Idoso de 80 Anos ou mais , Albuminúria/complicações , Albuminúria/urina , Biomarcadores/urina , Nefropatias Diabéticas/diagnóstico , Feminino , Humanos , Interleucina-18/urina , Masculino , Pessoa de Meia-Idade , Fator de Necrose Tumoral alfa/urina
6.
BMC Cancer ; 15: 62, 2015 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-25884851

RESUMO

BACKGROUND: Given the paucity of information on dose intensity, the objective of this study is to describe the use of adjuvant chemotherapy for stage III colon cancer, focusing on relative dose intensity (RDI), overall survival (OS) and disease-free survival (DFS). METHODS: Retrospective cohort of 367 patients diagnosed with stage III colon cancer in 2003-2008 and treated at 19 VA medical centers. Kaplan-Meier curves summarize 5-year OS and 3-year DFS by chemotherapy regimen and RDI, and multivariable Cox proportional hazards regression was used to model these associations. RESULTS: 5-fluorouracil/leucovorin (FU/LV) was the most commonly initiated regimen in 2003 (94.4%) and 2004 (62.7%); in 2005-2008, a majority of patients (60%-74%) was started on an oxaliplatin-based regimen. Median RDI was 82.3%. Receipt of >70% RDI was associated with better 5-year OS (p < 0.001) and 3-year DFS (P = 0.009) than was receipt of ≤70% RDI, with 5-year OS rates of 66.3% and 50.5%, respectively and 3-year DFS rates of 66.1% and 52.7%, respectively. In the multivariable analysis of 5-year OS, oxaliplatin + 5-FU/LV (versus 5-FU/LV) (HR = 0.55; 95% CI = 0.34-0.91), >70% RDI at the first year (HR = 0.58; 95% CI = 0.37-0.89) and married status (HR = 0.66; 95% CI = 0.45-0.97) were associated with significantly decreased risk of death, while age ≥75 (versus 55-64) (HR = 2.06; 95% CI = 1.25-3.40), Charlson Comorbidity Index (HR = 1.17; 95% CI = 1.06-1.30), T4 tumor status (versus T1/T2) (HR = 5.88; 95% CI = 2.69-12.9), N2 node status (HR = 1.68; 95% CI = 1.12-2.50) and bowel obstruction (HR = 2.32, 95% CI = 1.36-3.95) were associated with significantly increased risk. Similar associations were observed for DFS. CONCLUSION: Patients with stage III colon cancer who received >70% RDI had improved 5-year OS. The association between RDI and survival needs to be examined in studies of adjuvant chemotherapy for colon cancer outside of the VA.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/patologia , Veteranos , Idoso , Quimioterapia Adjuvante/métodos , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/efeitos adversos , Humanos , Leucovorina/administração & dosagem , Leucovorina/efeitos adversos , Masculino , Pessoa de Meia-Idade , Compostos Organoplatínicos/administração & dosagem , Compostos Organoplatínicos/efeitos adversos , Oxaliplatina , Estudos Retrospectivos , Fatores de Risco , Análise de Sobrevida , Resultado do Tratamento
7.
Cancer Gene Ther ; 31(4): 586-598, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38267623

RESUMO

Glutamate-NMDAR receptors (GRINs) have been reported to influence cancer immunogenicity; however, the relationship between GRIN alterations and the response to immune checkpoint inhibitors (ICIs) has not been determined. This study combined clinical characteristics and mutational profiles from multiple cohorts to form a discovery cohort (n = 901). The aim of this study was to investigate the correlation between the mutation status of the GRIN gene and the response to ICI therapy. Additionally, an independent ICI-treated cohort from the Memorial Sloan Kettering Cancer Center (MSKCC, N = 1513) was used for validation. Furthermore, this study explored the associations between GRIN2A mutations and intrinsic and extrinsic immunity using multiomics analysis. In the discovery cohort, patients with GRIN2A-MUTs had improved clinical outcomes, as indicated by a higher objective response rate (ORR: 36.8% vs 25.8%, P = 0.020), durable clinical benefit (DCB: 55.2% vs 38.7%, P = 0.005), prolonged progression-free survival (PFS: HR = 0.65; 95% CI 0.49 to 0.87; P = 0.003), and increased overall survival (OS: HR = 0.67; 95% CI 0.50 to 0.89; P = 0.006). Similar results were observed in the validation cohort, in which GRIN2A-MUT patients exhibited a significant improvement in overall survival (HR = 0.66; 95% CI = 0.49 to 0.88; P = 0.005; adjusted P = 0.045). Moreover, patients with GRIN2A-MUTs exhibited an increase in tumor mutational burden, high expression of costimulatory molecules, increased activity of antigen-processing machinery, and infiltration of various immune cells. Additionally, gene sets associated with cell cycle regulation and the interferon response were enriched in GRIN2A-mutated tumors. In conclusion, GRIN2A mutation is a novel biomarker associated with a favorable response to ICIs in multiple cancers.


Assuntos
Inibidores de Checkpoint Imunológico , Neoplasias , Humanos , Inibidores de Checkpoint Imunológico/farmacologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Neoplasias/tratamento farmacológico , Neoplasias/genética , Interferons , Mutação , Biomarcadores Tumorais/genética
8.
Curr Mol Pharmacol ; 2023 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-37881074

RESUMO

BACKGROUND: Cholangiopathies comprise a spectrum of diseases without curative treatments. Pharmacological treatments based on bile acid (BA) metabolism regulation represent promising therapeutic strategies for the treatment of cholangiopathies. Gentiopicroside (GPS), derived from the Chinese medicinal herb Gentianae Radix, exerts pharmacological effects on bile acid metabolism regulation and oxidative stress. OBJECTIVE: The present study aims to investigate the effect of GPS on 3,5-diethoxycarbonyl-1,4dihydrocollidine (DDC)-induced cholangiopathy. METHODS: Two independent animal experiments were designed to evaluate the comprehensive effect of GPS on chronic DDC diet-induced cholangiopathy, including bile duct obliteration, ductular reaction, BA metabolism reprogramming, liver fibrosis, oxidative stress and inflammatory responses. RESULTS: In the first pharmacological experiment, three doses of GPS (5, 25 and 125 mg/kg) were injected intraperitoneally into mice fed a DDC diet for 14 days. DDC induced a typical ductular reaction, increased periductal fibrosis and mixed inflammatory cell infiltration in the portal areas. GPS treatment showed dose-dependent improvements in the ductular reaction, BA metabolism, fibrosis, oxidative stress and inflammatory response. In the second experiment, a high dose of GPS was injected intraperitoneally into control mice for 28 days, resulting in no obvious histologic changes and significant serologic abnormalities in liver function. However, GPS inhibited DDC-induced oxidative stress, serum and hepatic BA accumulation, proinflammatory cytokine production, and immunocyte infiltration. Specifically, the GPS-treated groups showed decreased infiltration of monocyte-derived macrophages and CD4+ and CD8+ T lymphocytes, as well as preserved Kupffer cells. CONCLUSION: GPS alleviated chronic DDC diet-induced cholangiopathy disorder by improving the ductular reaction, periductal fibrosis, oxidative stress and inflammatory response. Its dosage-dependent pharmacological effects indicated that GPS warrants its further evaluation in clinical trials for cholangiopathy.

9.
J Tradit Complement Med ; 13(4): 345-357, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37396159

RESUMO

Purpose: Cholestatic liver diseases are groups of hepatobiliary diseases without curative drug-based therapy options. Regulation of bile acid (BA) metabolism, hepatoperiductal fibrosis, and inflammatory response indicated present novel methods for the treatment of cholestatic liver disease. Costunolide (COS) from herb Saussurea lappa exerts a pharmacological effect of regulation of BA metabolism, liver fbrosis and inflammatory response. The present study aimed to clarify the pharmacodynamic effects of COS against the murine model of cholestatic liver disease. Methods: We established a murine model of cholestatic liver disease through chronic feeding of 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC) diet for 28 days. Two independent in vivo experiments were designed to reveal the pharmacological effect of COS against cholestatic liver disease. In the first experiment, two dosages of COS (10 and 30 mg/kg) were intraperitoneally injected into model mice daily for 14 days. In the second experiment, high dosage of COS (30 mg/kg) was intraperitoneally injected into control and model mice daily for 28 days. Results: In the evaluation of the hepatoprotective effect of COS, COS showed dosage-dependent improvement of cholestatic liver disease, including ductular reaction, hepatoperiductal fibrosis, and inflammatory response. The mechanism of COS-mediated hepatoprotective effects mainly relies on the regulation of BA metabolism, and the inflammatory response. DDC diet feed induced hepatic BA metabolism, transport and circulation dysfunction. COS treatment not only regulated the BA metabolism and transport gene, but also reprogrammed hepatic primary and secondary BA concentrations. DDC induced hepatic infiltrated monocytes derived macrophages and lymphocytes were inhibited, while Kupffer cells were preserved by COS treatment. The liver elevating inflammatory cytokines of DDC diet feed were alleviated by COS. Moreover, high dosage of 30 mg/kg COS treatment for 28 days resulted in no significant serological changes and no obvious hepatic histopathological changes when compared with control mice. Conclusion: COS protected against DDC diet feeding-induced cholestatic liver disease since COS regulated BA metabolism, ductular reaction, hepatoperiductal fibrosis and inflammatory response. COS is suggested as a potential natural product for the treatment of cholestatic liver disease.

10.
Exp Cell Res ; 317(6): 838-48, 2011 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-21211535

RESUMO

High levels of the soluble form of E-cadherin can be found in the serum of cancer patients and are associated with poor prognosis. Despite the possible predictive value of soluble E-cadherin, little is understood concerning its patho-physiological consequences in tumor progression. In this study, we show that soluble E-cadherin facilitates cell survival via functional interaction with cellular E-cadherin. Exposure of cells to a recombinant form of soluble E-cadherin, at a concentration found in cancer patient's serum, prevents apoptosis due to serum/growth factor withdrawal, and inhibits epithelial lumen formation, a process that requires apoptosis. Further, soluble E-cadherin-mediated cell survival involves activation of the epidermal growth factor receptor (EGFR) and EGFR-mediated activation of both phosphoinositide-3 kinase (PI3K)/AKT and ERK1/2 signaling pathways. These results are evidence of a complex functional interplay between EGFR and E-cadherin and also suggest that the presence of soluble E-cadherin in cancer patients' sera might have relevance to cell survival and tumor progression.


Assuntos
Apoptose/efeitos dos fármacos , Caderinas/farmacologia , Receptores ErbB/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Caderinas/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Células HEK293 , Humanos , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Proteína Oncogênica v-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais/efeitos dos fármacos , Solubilidade
11.
Cell Oncol (Dordr) ; 45(1): 163-178, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35089546

RESUMO

PURPOSE: Hepatocellular carcinoma (HCC) is one of the most common cancers in the world with a high mortality rate. Receptor tyrosine kinases play important roles in the occurrence and development of various cancers. Discoid protein domain receptor 1 (DDR1) is a special type of transmembrane receptor tyrosine kinase. Here, we show that the expression of DDR1 is significantly increased in HCC and is related to a poor clinical prognosis. METHODS: The expression of DDR1 in HCC cell lines and primary HCC specimens was evaluated using Western blotting and immunohistochemistry. A correlation between DDR1 and SLC1A5 expression was also investigated in primary HCC specimens. Cell proliferation was evaluated using in vitro CCK8 and colony formation assays. Gene knock-down and overexpression assays, CHX, NH4CL and Mg132 interference tests and immunoprecipitation, as well as nude mouse xenograft models were used to assess the mechanism by which DDR1 promotes tumorigenesis in vitro and in vivo. RESULTS: We found that DDR1 promotes the proliferation of HCC cells and accelerates the growth of HCC tumor xenografts, while DDR1 downregulation had the opposite effect. We also found that loss or gain of DDR1 expression affected HCC cell cycle progression. Mechanistically, we found that DDR1 interacts with SLC1A5, which belongs to the solute carrier (SLC) family of transporters, and regulates its stability, thereby affecting the mTORC1 signaling pathway. In addition, we found that SLC1A5 regulation by DDR1 can be restored by lysosome inhibitors. We also found that DDR1 is highly expressed in HCC tissues and that increased DDR1 expression predicts a shorter overall survival (OS) time. We additionally found that the expression of SLC1A5 was positively correlated with that of DDR1. Together, our data indicate that DDR1 acts as a tumor-promoting factor that can control HCC cell proliferation and cell cycle progression by stabilizing SLC1A5 in a lysosome-dependent way. CONCLUSIONS: Our study reveals a new mechanism by which DDR1 plays a liver cancer-promoting role. We also found that DDR1 expression serves as an independent prognostic marker, and that DDR1 and SLC1A5 expression levels are positively correlated in clinical samples. Our findings provide a new perspective for understanding HCC development and offers new targets for the treatment and management of HCC.


Assuntos
Sistema ASC de Transporte de Aminoácidos , Carcinoma Hepatocelular , Receptor com Domínio Discoidina 1/metabolismo , Neoplasias Hepáticas , Sistema ASC de Transporte de Aminoácidos/genética , Animais , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Proliferação de Células , Receptor com Domínio Discoidina 1/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Hepáticas/patologia , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Camundongos , Antígenos de Histocompatibilidade Menor , Transdução de Sinais
12.
Mol Cancer Ther ; 18(9): 1565-1576, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31270152

RESUMO

Amplification of the epidermal growth factor receptor gene (EGFR) represents one of the most commonly observed genetic lesions in glioblastoma (GBM); however, therapies targeting this signaling pathway have failed clinically. Here, using human tumors, primary patient-derived xenografts (PDX), and a murine model for GBM, we demonstrate that EGFR inhibition leads to increased invasion of tumor cells. Further, EGFR inhibitor-treated GBM demonstrates altered oxidative stress, with increased lipid peroxidation, and generation of toxic lipid peroxidation products. A tumor cell subpopulation with elevated aldehyde dehydrogenase (ALDH) levels was determined to comprise a significant proportion of the invasive cells observed in EGFR inhibitor-treated GBM. Our analysis of the ALDH1A1 protein in newly diagnosed GBM revealed detectable ALDH1A1 expression in 69% (35/51) of the cases, but in relatively low percentages of tumor cells. Analysis of paired human GBM before and after EGFR inhibitor therapy showed an increase in ALDH1A1 expression in EGFR-amplified tumors (P < 0.05, n = 13 tumor pairs), and in murine GBM ALDH1A1-high clones were more resistant to EGFR inhibition than ALDH1A1-low clones. Our data identify ALDH levels as a biomarker of GBM cells with high invasive potential, altered oxidative stress, and resistance to EGFR inhibition, and reveal a therapeutic target whose inhibition should limit GBM invasion.


Assuntos
Neoplasias Encefálicas/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Glioblastoma/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto/métodos , Família Aldeído Desidrogenase 1/metabolismo , Animais , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Dasatinibe/farmacologia , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/metabolismo , Cloridrato de Erlotinib/farmacologia , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Camundongos , Estresse Oxidativo/efeitos dos fármacos , Retinal Desidrogenase/metabolismo
13.
N Engl J Med ; 353(19): 2012-24, 2005 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-16282176

RESUMO

BACKGROUND: The epidermal growth factor receptor (EGFR) is frequently amplified, overexpressed, or mutated in glioblastomas, but only 10 to 20 percent of patients have a response to EGFR kinase inhibitors. The mechanism of responsiveness of glioblastomas to these inhibitors is unknown. METHODS: We sequenced kinase domains in the EGFR and human EGFR type 2 (Her2/neu) genes and analyzed the expression of EGFR, EGFR deletion mutant variant III (EGFRvIII), and the tumor-suppressor protein PTEN in recurrent malignant gliomas from patients who had received EGFR kinase inhibitors. We determined the molecular correlates of clinical response, validated them in an independent data set, and identified effects of the molecular abnormalities in vitro. RESULTS: Of 49 patients with recurrent malignant glioma who were treated with EGFR kinase inhibitors, 9 had tumor shrinkage of at least 25 percent. Pretreatment tissue was available for molecular analysis from 26 patients, 7 of whom had had a response and 19 of whom had rapid progression during therapy. No mutations in EGFR or Her2/neu kinase domains were detected in the tumors. Coexpression of EGFRvIII and PTEN was significantly associated with a clinical response (P<0.001; odds ratio, 51; 95 percent confidence interval, 4 to 669). These findings were validated in 33 patients who received similar treatment for glioblastoma at a different institution (P=0.001; odds ratio, 40; 95 percent confidence interval, 3 to 468). In vitro, coexpression of EGFRvIII and PTEN sensitized glioblastoma cells to erlotinib. CONCLUSIONS: Coexpression of EGFRvIII and PTEN by glioblastoma cells is associated with responsiveness to EGFR kinase inhibitors.


Assuntos
Receptores ErbB/genética , Glioblastoma/genética , PTEN Fosfo-Hidrolase/metabolismo , Inibidores de Proteínas Quinases/uso terapêutico , Adulto , Idoso , Antineoplásicos/uso terapêutico , DNA de Neoplasias/análise , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/metabolismo , Cloridrato de Erlotinib , Feminino , Gefitinibe , Amplificação de Genes , Deleção de Genes , Expressão Gênica , Genes erbB-1 , Genes erbB-2 , Glioblastoma/tratamento farmacológico , Glioblastoma/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Oligodendroglioma/tratamento farmacológico , Oligodendroglioma/genética , Oligodendroglioma/metabolismo , PTEN Fosfo-Hidrolase/genética , Reação em Cadeia da Polimerase , Quinazolinas/uso terapêutico , Análise de Sequência de DNA , Transdução de Sinais
14.
Neuro Oncol ; 10(3): 254-64, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18359864

RESUMO

Glioblastoma multiforme (GBM) is one the most aggressive brain tumors due to the fast and invasive growth that is partly supported by the presence of extensive neovascularization. The matrix metalloproteinase MMP-2 has been associated with invasive and angiogenic properties in gliomas and is a marker of poor prognosis. Since MMP-2 is expressed in both tumor cells and endothelial cells in GBM, we generated genetically engineered MMP-2 knockout (MMP-2ko) GBM to examine the importance of the spatial expression of MMP-2 in tumor and/or normal host-derived cells. MMP-2-dependent effects appeared to be dose-dependent irrespective of its expression pattern. GBM completely devoid of MMP-2 exhibited markedly increased vascular density associated with vascular endothelial growth factor receptor 2 (VEGFR2) activation and enhanced vascular branching and sprouting. Surprisingly, despite the high vascular density, tumor cells were more prone to apoptosis, which led to prolonged survival of tumor-bearing mice, suggesting that the increased vascularity is not functional. Congruently, tumor vessels were poorly perfused, exhibited lower levels of VEGFR2, and did not undergo proper maturation because pericytes of MMP-2ko tumors were not activated and were less abundant. As a result of impaired and dysfunctional angiogenesis, MMP-2ko GBM became more invasive, predominantly by migrating along blood vessels into the brain parenchyma.


Assuntos
Neoplasias Encefálicas/enzimologia , Glioblastoma/enzimologia , Metaloproteinase 2 da Matriz/metabolismo , Invasividade Neoplásica , Neovascularização Patológica/enzimologia , Animais , Western Blotting , Neoplasias Encefálicas/irrigação sanguínea , Neoplasias Encefálicas/patologia , Sobrevivência Celular/fisiologia , Citometria de Fluxo , Glioblastoma/irrigação sanguínea , Glioblastoma/patologia , Imuno-Histoquímica , Hibridização In Situ , Metaloproteinase 2 da Matriz/genética , Camundongos , Camundongos Knockout , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo
15.
Nat Cell Biol ; 20(10): 1203-1214, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30202050

RESUMO

Glioblastoma multiforme (GBMs) are recurrent lethal brain tumours. Recurrent GBMs often exhibit mesenchymal, stem-like phenotypes that could explain their resistance to therapy. Analyses revealed that recurrent GBMs have increased tension and express high levels of glycoproteins that increase the bulkiness of the glycocalyx. Studies showed that a bulky glycocalyx potentiates integrin mechanosignalling and tissue tension and promotes a mesenchymal, stem-like phenotype in GBMs. Gain- and loss-of-function studies implicated integrin mechanosignalling as an inducer of GBM growth, survival, invasion and treatment resistance, and a mesenchymal, stem-like phenotype. Mesenchymal-like GBMs were highly contractile and expressed elevated levels of glycoproteins that expanded their glycocalyx, and they were surrounded by a stiff extracellular matrix that potentiated integrin mechanosignalling. Our findings suggest that there is a dynamic and reciprocal link between integrin mechanosignalling and a bulky glycocalyx, implying a causal link towards a mesenchymal, stem-like phenotype in GBMs. Strategies to ameliorate GBM tissue tension offer a therapeutic approach to reduce mortality due to GBM.


Assuntos
Neoplasias Encefálicas/metabolismo , Glioblastoma/metabolismo , Glicocálix/metabolismo , Integrinas/metabolismo , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Neoplásicas/metabolismo , Animais , Antineoplásicos Alquilantes/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/genética , Sobrevivência Celular/efeitos dos fármacos , Retroalimentação Fisiológica/efeitos dos fármacos , Glioblastoma/tratamento farmacológico , Glioblastoma/genética , Humanos , Células-Tronco Mesenquimais/efeitos dos fármacos , Camundongos Nus , Células-Tronco Neoplásicas/efeitos dos fármacos , Tensão Superficial , Temozolomida/uso terapêutico , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
16.
Oncogene ; 22(15): 2361-73, 2003 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-12700671

RESUMO

Epidermal growth factor receptor (EGFR) overexpression occurs in nearly 50% of cases of glioblastoma (GBM), but its clinical and biological implications are not well understood. We have used Affymetrix high-density oligonucleotide arrays to demonstrate that EGFR-overexpressing GBMs (EGFR+) have a distinct global gene transcriptional profile. We show that the expression of 90 genes can distinguish EGFR+ from EGFR nonexpressing (EGFR-) GBMs, including a number of genes known to act as growth/survival factors for GBMs. We have also uncovered two additional novel molecular subtypes of GBMs, one of which is characterized by coordinate upregulation of contiguous genes on chromosome 12q13-15 and expression of both astrocytic and oligodendroglial genes. These results define distinct molecular subtypes of GBMs that may be important in disease stratification, and in the discovery and assessment of GBM treatment strategies.


Assuntos
Neoplasias Encefálicas/classificação , Perfilação da Expressão Gênica , Glioblastoma/classificação , Análise de Sequência com Séries de Oligonucleotídeos , Astrócitos/metabolismo , Astrócitos/patologia , Biópsia , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Diferenciação Celular , Linhagem da Célula , Cromossomos Humanos Par 12/genética , Receptores ErbB/biossíntese , Receptores ErbB/genética , Regulação Neoplásica da Expressão Gênica , Glioblastoma/genética , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/genética , Oligodendroglia/metabolismo , Oligodendroglia/patologia , RNA Mensageiro/genética , RNA Neoplásico/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Técnica de Subtração , Transcrição Gênica
17.
Artigo em Zh | MEDLINE | ID: mdl-26263773

RESUMO

OBJECTIVE: To understand the characteristics of pro-apoptotic gene SjBAD of Schistosoma japonicum, such as its biology, immunology, and transcriptional expression, and evaluate its potential of the recombinant protein as a vaccine candidate for schistosomiasis. METHODS: SjBAD was amplified by PCR and subeloned into a pET-28a(+) vector, and the recombinant plasmid was transformed into competent E. coli BL21 for producing recombinant protein. The expressions of SjBAD in different development stages of schistosomula and 42-day male and female worms were determined by real-time PCR. The immunogenicity of the recombinant protein was analyzed by Western blotting and ELISA. The potential of this protein as a vaccine candidate molecule was assessed by testing the worm reduction rate and liver egg reduction rate in the BALB/c mice immunized by the recombinant antigen SjBAD. RESULTS: SjBAD was successfully cloned, the recombinant plasmid pET-28a(+)-SjBAD was successfully expressed in E. coli, and the molecular weight of the recombinant protein was around 22 kDa. Western-blotting showed that the recombinant protein had good immunogenicity. The recombinant protein could induce high level of specific IgG antibodies in the BALB/c mice. SjBAD was expressed in all tested 7-, 14-, 21-, 28-, 35- and 42-day worms, and was highly expressed in 14-day schistosomula, while the expression level in 42-day male worms was higher than that in 42-day female worms. Two in- dependent animal trials showed that 30.82% and 27.87% worm reduction rates, as well as 42.52% and 45.84% liver eggs reduction rates were obtained in the rSjBAD vaccinated group compared with those of the blank control group (both P < 0.05). CONCLUSIONS: The proapoptotic gene SjBAD is successfully cloned and expressed. The gene is expressed in different development stages of S. japonicum. The rSjBAD vaccinated BALB/c mice can obtain a partial protective immunity against S. japonicum infection.


Assuntos
Schistosoma japonicum/genética , Proteína de Morte Celular Associada a bcl/genética , Animais , Anticorpos Anti-Helmínticos/sangue , Feminino , Imunoglobulina G/sangue , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Reação em Cadeia da Polimerase em Tempo Real , Proteínas Recombinantes/imunologia , Schistosoma japonicum/imunologia , Vacinação , Proteína de Morte Celular Associada a bcl/imunologia
18.
CNS Oncol ; 2(1): 49-65, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23750318

RESUMO

Angiogenesis inhibitors targeting the VEGF signaling pathway have been US FDA approved for various cancers including glioblastoma (GBM), one of the most lethal and angiogenic tumors. This has led to the routine use of the anti-VEGF antibody bevacizumab in recurrent GBM, conveying substantial improvements in radiographic response, progression-free survival and quality of life. Despite these encouraging beneficial effects, patients inevitably develop resistance and frequently fail to demonstrate significantly better overall survival. Unlike chemotherapies, to which tumors exhibit resistance due to genetic mutation of drug targets, emerging evidence suggests that tumors bypass antiangiogenic therapy while VEGF signaling remains inhibited through a variety of mechanisms that are just beginning to be recognized. Because of the indirect nature of resistance to VEGF inhibitors there is promise that strategies combining angiogenesis inhibitors with drugs targeting such evasive resistance pathways will lead to more durable antiangiogenic efficacy and improved patient outcomes. Further identifying and understanding of evasive resistance mechanisms and their clinical importance in GBM relapse is therefore a timely and critical issue.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Glioblastoma/tratamento farmacológico , Glioblastoma/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Humanos , Transdução de Sinais/efeitos dos fármacos
19.
Exp Ther Med ; 6(6): 1482-1488, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24250725

RESUMO

The aim of this study was to investigate the correlation of the proinflammatory marker tumor necrosis factor-α (TNF-α) and the tubular marker neutrophil gelatinase-associated lipocalin (NGAL) with the progression of the early stage of type 2 diabetic nephropathy (DN). Baseline levels of urinary TNF-α and NGAL were measured in 63 non-diabetic controls and 201 patients with type 2 diabetes and different albuminuria statuses. The patients with diabetes (n=125) with normo- or microalbuminuria were subsequently followed-up for 28 (25-32) months, with routine measurements of creatinine and urinary albumin excretion (UAE). It was observed that baseline levels of urinary TNF-α and NGAL were significantly elevated and correlated with the severity of albuminuria in patients with diabetes. During the follow-up, the urinary levels of TNF-α and NGAL were observed to be significantly correlated with a rapid decline in the estimated glomerular filtration rate (eGFR). Following adjustment for other progression promoters, including albuminuria, TNF-α remained a significant predictor of eGFR decline. These results suggest that inflammation is important in the pathogenesis of DN and indicate that TNF-α may be used as an independent predictor for the progression of DN at the early stage.

20.
Artigo em Inglês | MEDLINE | ID: mdl-23589719

RESUMO

This study aimed to examine the role of GLP-1 in the hypoglycemic activity of wild bitter gourd (Momordica charantia L., BG). In vitro, the GLP-1 secretion in STC-1, a murine enteroendocrine cell line, was dose dependently stimulated by water extract (WE), its fractions (WEL, >3 kD and WES, <3 kD), and a bitter compounds-rich fraction of BG. These stimulations were partially inhibited by probenecid, a bitter taste receptor inhibitor, and by U-73122, a phospholipase C ß 2 inhibitor. These results suggested that the stimulation might involve, at least in part, certain bitter taste receptors and/or PLC ß 2-signaling pathway. Two cucurbitane triterpenoids isolated from BG, 19-nor-cucurbita-5(10),6,8,22-(E),24-pentaen-3 ß -ol, and 5 ß ,19-epoxycucurbita-6,24-diene-3 ß ,23 ξ -diol (karavilagenine E,) showed relative high efficacy in the stimulation. In vivo, mice fed BG diet showed higher insulinogenic index in an oral glucose tolerance test. A single oral dose of WE or WES pretreatment significantly improved intraperitoneal glucose tolerance. A single oral dose of WES significantly decreased glucose and increased insulin and GLP-1 in serum after 30 min. This acute hypoglycemic effect of WES was abolished by pretreatment with exendin-9, a GLP-1 receptor antagonist. Our data provide evidence that BG stimulates GLP-1 secretion which contributes, at least in part, to the antidiabetic activity of BG through an incretin effect.

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