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1.
Cancer Lett ; 593: 216930, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38705566

RESUMO

Radiotherapy (RT) in non-small cell lung cancer (NSCLC) triggers cellular senescence, complicating tumor microenvironments and affecting treatment outcomes. This study examines the role of lymphocyte immunoglobulin-like receptor B2 (LILRB2) in modulating RT-induced senescence and radiosensitivity in NSCLC. Through methodologies including irradiation, lentivirus transfection, and various molecular assays, we assessed LILRB2's expression and its impact on cellular senescence levels and tumor cell behaviors. Our findings reveal that RT upregulates LILRB2, facilitating senescence and a senescence-associated secretory phenotype (SASP), which in turn enhances tumor proliferation and resistance to radiation. Importantly, LILRB2 silencing attenuates these effects by inhibiting the JAK2/STAT3 pathway, significantly increasing radiosensitivity in NSCLC models. Clinical data correlate high LILRB2 expression with reduced RT response and poorer prognosis, suggesting LILRB2's pivotal role in RT-induced senescence and its potential as a therapeutic target to improve NSCLC radiosensitivity.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Senescência Celular , Neoplasias Pulmonares , Tolerância a Radiação , Receptores Imunológicos , Humanos , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Senescência Celular/efeitos da radiação , Tolerância a Radiação/genética , Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/metabolismo , Receptores Imunológicos/genética , Receptores Imunológicos/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos da radiação , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Fator de Transcrição STAT3/metabolismo , Fator de Transcrição STAT3/genética , Animais , Janus Quinase 2/metabolismo , Janus Quinase 2/genética , Camundongos , Transdução de Sinais , Regulação Neoplásica da Expressão Gênica/efeitos da radiação , Fenótipo Secretor Associado à Senescência/genética , Células A549 , Feminino
2.
Front Oncol ; 13: 1066360, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37007065

RESUMO

Objective: To establish a nomogram based on non-enhanced computed tomography(CT) imaging radiomics and clinical features for use in predicting the malignancy of sub-centimeter solid nodules (SCSNs). Materials and methods: Retrospective analysis was performed of records for 198 patients with SCSNs that were surgically resected and examined pathologically at two medical institutions between January 2020 and June 2021. Patients from Center 1 were included in the training cohort (n = 147), and patients from Center 2 were included in the external validation cohort (n = 52). Radiomic features were extracted from chest CT images. The least absolute shrinkage and selection operator (LASSO) regression model was used for radiomic feature extraction and computation of radiomic scores. Clinical features, subjective CT findings, and radiomic scores were used to build multiple predictive models. Model performance was examined by evaluating the area under the receiver operating characteristic curve (AUC). The best model was selected for efficacy evaluation in a validation cohort, and column line plots were created. Results: Pulmonary malignant nodules were significantly associated with vascular alterations in both the training (p < 0.001) and external validation (p < 0.001) cohorts. Eleven radiomic features were selected after a dimensionality reduction to calculate the radiomic scores. Based on these findings, three prediction models were constructed: subjective model (Model 1), radiomic score model (Model 2), and comprehensive model (Model 3), with AUCs of 0.672, 0.888, and 0.930, respectively. The optimal model with an AUC of 0.905 was applied to the validation cohort, and decision curve analysis indicated that the comprehensive model column line plot was clinically useful. Conclusion: Predictive models constructed based on CT-based radiomics with clinical features can help clinicians diagnose pulmonary nodules and guide clinical decision making.

3.
Thorac Cancer ; 14(4): 339-347, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36524684

RESUMO

Anastomotic leak is still a severe complication in esophageal surgery due to high mortality. This article reviews the updates on the treatment of anastomotic leak after esophagectomy in order to provide reference for clinical treatment and research. The relevant studies published in the Chinese Zhiwang, Wanfang, and MEDLINE databases to December 21, 2021 were retrieved, and esophageal carcinoma, esophagectomy, anastomotic leakage, and fistula selected as the keywords. A total of 78 studies were finally included. The treatments include traditional surgical drainage, new reverse drainage trans-fistula, stent plugging, endoscopic clamping, biological protein glue injection plugging, endoluminal vacuum therapy (EVT), and reoperation, etc. Early diagnosis, accurate classification and optimal treatment can promote the rapid healing of anastomotic leaks. EVT may be the most valuable approach, simultaneously with good commercial prospects. Reoperation should be considered in patients with complex fistula in which conservative treatment is insufficient or has failed.


Assuntos
Fístula Anastomótica , Neoplasias Esofágicas , Humanos , Fístula Anastomótica/diagnóstico , Fístula Anastomótica/etiologia , Fístula Anastomótica/cirurgia , Neoplasias Esofágicas/cirurgia , Neoplasias Esofágicas/complicações , Esofagectomia/efeitos adversos , Anastomose Cirúrgica/efeitos adversos , Estudos Retrospectivos , Resultado do Tratamento
4.
Front Oncol ; 12: 699824, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35832544

RESUMO

Background: The function of angiogenesis-related genes (ARGs) in lung adenocarcinoma (LUAD) remains poorly documented. This study was designed to reveal ARGs in LUAD and related networks. Methods: We worked with sequencing data and clinical information pertaining to LUAD from public databases. ARGs were retrieved from the HALLMARK_ANGIOGENESIS gene set. Differential analysis and Kaplan-Meier (K-M) analysis were performed to authenticate the ARGs associated with LUAD. Weighted gene correlation network analysis was performed on the mining hub genes linked to the abovementioned genes, and functional enrichment analysis was done. Subsequently, Cox regression analyses were used to construct the prognostic gene. POSTN and microvessel density were detected using immunohistochemistry. Results: POSTN, an ARG that was highly expressed in patients with LUAD and was closely associated with their weak overall survival was identified. Differentially expressed genes associated with POSTN were mainly enriched in entries related to the tubulointerstitial system, immune response, and epithelial cells. A positive correlation was demonstrated between POSTN expression and tumor microvessel density in LUAD. Subsequently, a prognostic gene signature was constructed and revealed that 4 genes may predict the survival of LUAD patients. Furthermore, the ESTIMATE and CIBERSORT analyses suggested that our risk scoring system may be implicated in altering the immune microenvironment of patients with LUAD. Finally, a ceRNA network was constructed based on the prognostic genes, and the regulatory networks were examined. Conclusion: POSTN, a novel prognostic gene signature associated with ARGs, was constructed for the prognosis of patients with LUAD. This signature may alter the immune microenvironment by modulating the activation of the tubulointerstitial system, epithelial cells, and immune cells, ultimately affecting patient survival.

5.
Front Pharmacol ; 12: 684545, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34603016

RESUMO

Esophageal cancer is the ninth most common malignancy worldwide, ranking sixth in mortality. Platinum-based chemotherapy is commonly used for treating locally advanced esophageal cancer, yet it is ineffective in a large portion of patients. There is a need for reliable molecular markers with direct clinical application for a prospective selection of patients who can benefit from chemotherapy and patients in whom toxicity is likely to outweigh the benefit. The cytotoxic activity of platinum derivatives largely depends on the uptake and accumulation into cells, primarily by organic cation transporters (OCTs). The aim of the study was to investigate the impact of OCT expression on the clinical outcome of patients with esophageal cancer treated with oxaliplatin. Twenty patients with esophageal squamous cell carcinoma (SCC) were prospectively enrolled and surgical specimens used for screening OCT expression level by western blotting and/or immunostaining, and for culture of cancer cells. Sixty-seven patients with SCC who received oxaliplatin and for whom follow-up was available were retrospectively assessed for organic cation/carnitine transporter 2 (OCTN2) expression by real time RT-PCR and immunostaining. OCTN2 staining was also performed in 22 esophageal adenocarcinomas. OCTN2 function in patient-derived cancer cells was evaluated by assessing L-carnitine uptake and sensitivity to oxaliplatin. The impact of OCTN2 on oxaliplatin activity was also assessed in HEK293 cells overexpressing OCTN2. OCTN2 expression was higher in tumor than in normal tissues. In patient-derived cancer cells and HEK293 cells, the expression of OCTN2 sensitized to oxaliplatin. Patients treated with oxaliplatin who had high OCTN2 level in the tumor tissue had a reduced risk of recurrence and a longer survival time than those with low expression of OCTN2 in tumor tissue. In conclusion, OCTN2 is expressed in esophageal cancer and it is likely to contribute to the accumulation and cytotoxic activity of oxaliplatin in patients with esophageal carcinoma treated with oxaliplatin.

6.
Onco Targets Ther ; 12: 10739-10747, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31849482

RESUMO

OBJECTIVE: To investigate the expression of tumor suppressor protein ASK1-interacting protein-1 (AIP1) in cancer tissues of patients with early-stage non-small cell lung cancer (NSCLC) and its correlation with tumor progression, tumor angiogenesis and prognosis. METHODS: A total of 136 patients with stage I NSCLC who underwent radical resection of lung cancer in Qianfoshan Hospital of Shandong Province from January 2011 to December 2011 were enrolled. Immunohistochemistry was used to detect AIP1 protein in tumor tissues. Vascular endothelial CD34 immunohistochemical staining was used to count intratumoral microvessel density (MVD). SPSS 19.0 software was used to analyze the relationship between AIP1 protein expression and clinicopathological features, tumor angiogenesis and prognosis. RESULTS: Low expression of AIP1 was more common in tumor tissues with high MVD, and patients with low expression of AIP1 were more likely to have tumor recurrence. Multivariate analysis showed that low expression of AIP1 had predictive value for overall survival, disease-free survival, and disease-specific survival. CONCLUSION: Downregulation of AIP1 protein expression is associated with lung cancer progression, tumor angiogenesis and poor prognosis. Consequently, AIP1 may prove to be an important predictor of recovery from lung cancer and could become a new therapeutic target for lung cancer treatment.

7.
Onco Targets Ther ; 11: 7699-7707, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30464518

RESUMO

OBJECTIVE: To investigate the expression of tumor suppressor protein ASK1-interacting protein-1 (AIP1) in human esophageal squamous cell carcinoma (ESCC) and its role in tumor progression, angiogenesis, and prognosis. METHODS: A total of 117 biopsy samples were obtained from ESCC patients. None of the patients had distant metastasis before surgery, and did not receive preoperative chemotherapy or radiotherapy. Immunohistochemistry was used to detect the expression of AIP1 protein and vascular endothelial growth factor receptor 2 (VEGFR2) in ESCC specimens collected from 117 patients who underwent esophageal cancer radical surgery. Microvessel density (MVD) was evaluated by immunohistochemical staining of vascular endothelial CD34. The correlation between AIP1 protein and clinicopathological characteristics, tumor angiogenesis, and prognosis was analyzed. RESULTS: The downregulation of AIP1 protein in esophageal carcinoma tissues was detected in 63 cases. This downregulation significantly correlated with lymph node metastasis, clinicopathological staging, and tumor MVD (P<0.05). Survival analysis showed that ESCC patients with a low expression of AIP1, a high expression of VEGFR2, and a high level of MVD had a lower 5-year survival rate (P<0.05). Multivariate analysis confirmed that the downregulation of AIP1 significantly affected patient survival. CONCLUSION: The downregulation of AIP1 correlated with ESCC progression, tumor angiogenesis, and poor prognosis. AIP1 could be a promising biomarker for predicting ESCC prognosis and a potential target for anti-angiogenic therapy.

8.
Oncol Lett ; 10(4): 2283-2288, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26622835

RESUMO

Tripartite motif-containing 29 (TRIM29) is a member of the tripartite motif (TRIM) protein family. TRIM29 has been reported to be deregulated in a number of cancer types, suggesting the oncogenic function of TRIM29. However, its clinical significance in non-small cell lung cancer (NSCLC) has not been fully elucidated. In the present study, the TRIM29 expression status was investigated by immunohistochemical analysis in paraffin-embedded specimens obtained from 320 patients with surgically resected NSCLC, treated between 2000 and 2007. High TRIM29 expression was significantly associated with smoking (P=0.012), T stage (P=0.015) and M stage (P=0.003). Furthermore, elevated TRIM29 expression level was correlated with reduced overall (OS) and disease-free survival. In addition, high TRIM29 expression was an independent prognostic factor for OS [P=0.003, hazard ratio (HR)=2.102, 95% confidence interval (CI), 1.069-3.193]. In conclusion, these results suggest that TRIM29 may be a useful prognostic marker in NSCLC patients and a potential molecular target for NSCLC treatment.

9.
Int J Clin Exp Pathol ; 8(2): 1384-92, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25973022

RESUMO

Barrett's esophagus (BE) is associated with the development of esophageal adenocarcinoma (EAC). Bile acids (BAs) refluxing into the esophagus contribute to esophageal injury, which results in BE and subsequent EAC. We developed two animal models to test the role of BAs in the pathogenesis of BE. We surgically generated BA reflux, with or without gastric acid, in rats. In a second experiment, we fed animals separately with BAs and gastric acid. Pathologic changes were examined and the expression of Muc2 and Cdx2 in BE tissue was tested by immunostaining. Inflammatory factors in the plasma, as well as differentiation genes in BE were examined through highly sensitive ELISA and semi-quantitative RT-PCR techniques. We found that BAs are sufficient for the induction of esophagitis and Barrett's-like metaplasia in the esophagus. Overexpression of inflammatory cells, IL-6, and TNF-α was observed both in animals fed with BAs and surgically generated BA reflux. Furthermore, elevated levels of Cdx2, Muc2, Bmp4, Kit19, and Tff2 (differentiation genes in BE) were found in BA-treated rats. In conclusion, BAs, but not gastric acid, are a major causative factor for BE. We confirmed that BAs contribute to the development of BE by inducing the inflammatory response in the esophagus. Inhibiting BAs may be a promising therapy for BE.


Assuntos
Esôfago de Barrett/induzido quimicamente , Ácidos e Sais Biliares , Esôfago/patologia , Ácido Gástrico , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Animais , Esôfago de Barrett/metabolismo , Esôfago de Barrett/patologia , Fator de Transcrição CDX2 , Modelos Animais de Doenças , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/patologia , Esôfago/metabolismo , Refluxo Gastroesofágico/metabolismo , Refluxo Gastroesofágico/patologia , Proteínas de Homeodomínio/metabolismo , Masculino , Mucina-2/metabolismo , Ratos , Ratos Wistar , Fatores de Transcrição/metabolismo
10.
Hepatol Res ; 41(10): 1000-8, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21951873

RESUMO

AIM: Activation of adrenergic receptors (AR) has been reported to enhance the growth and invasion of various malignancies. The effects of AR agonists on malignant hepatocyte proliferation and migration have yet to be determined. METHODS: PLC/PRF/5 (PLC) and Huh-7 cells were exposed to a wide range of concentrations of the AR agonists noradrenaline (NA) and isoprenaline. Cell proliferation, migration, intracellular cyclic adenosine monophosphate (cAMP), protein kinase A (PKA) and C (PKC), matrix metalloproteinases (MMP)-2, -3, -7 and -9, and α(1) -, ß(1) - and ß(2) -AR expression were documented in both cell lines. RESULTS: Cell proliferative activity was unaltered following exposure to physiological and stress-related concentrations of AR agonists but migration was accelerated, an effect that was inhibited by the nonselective ß-AR antagonist labetalol. cAMP, PKA, PKC or MMP expression remained unchanged. Although α(1) - and ß(1) -AR expressions were abundant, ß(2) -AR expression was limited in both cell lines. CONCLUSION: Unlike other malignancies studied to date, in this study, the proliferative activity of malignant hepatocytes was not increased by exposure to AR agonists, a finding that could be explained by downregulation of ß(2) -AR expression. The increase in malignant hepatocyte migration observed remains unexplained but does not appear to involve adenyl cyclase or MMP signaling pathways.

12.
Zhonghua Wai Ke Za Zhi ; 46(1): 61-4, 2008 Jan 01.
Artigo em Chinês | MEDLINE | ID: mdl-18510008

RESUMO

OBJECTIVE: To study the inhibitory effects of antisense bicistronic recombinant adenovirus vector of ornithine decarboxylase (ODC) and S-adenosylmethionine decarboxylase (Ad-ODC-AdoMetDCas) on polyamine biosynthesis,proliferation and invasion of lung cancer cells. METHODS: Adenovirus-mediated gene transduction efficiency was assessed with counting GFP-positive cells using trypan blue. Western Blot and HPLC were used to detect ODC and S-AdoMetDC expression and polyamine content in A-549 cells respectively. Viable cell counting and cell cycle analysis were adopted to evaluate cell growth and cell cycle distribution, and A-549 cell invasion in vitro was detected with Matrigel invasion assay. RESULTS: Approximate 75% of A-549 cells were infected with Ad-ODC-AdoMetDCas when multiplicity of infection reached 50. Our study demonstrated that Ad-ODC-AdoMetDCas vector-mediated gene transfer inhibited tumor cell growth through the blockade of polyamine synthesis pathway. The tumor cells were arrested at cell cycle G1 phase after gene transfer. Gene transferred tumor cells were shown to possess markedly decreased invasiveness. CONCLUSION: Ad-ODC-AdoMetDCas has significant inhibitory effects on lung cancer cell proliferation and invasion and bears therapeutic potential for the treatment of lung cancer.


Assuntos
Adenosilmetionina Descarboxilase/genética , Proliferação de Células , Ornitina Descarboxilase/genética , RNA Antissenso/genética , Adenosilmetionina Descarboxilase/metabolismo , Adenoviridae/genética , Western Blotting , Ciclo Celular , Linhagem Celular Tumoral , Movimento Celular , Cromatografia Líquida de Alta Pressão , Vetores Genéticos , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Ornitina Descarboxilase/metabolismo , Poliaminas/metabolismo , Transfecção
13.
Dig Dis Sci ; 53(3): 794-8, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17934848

RESUMO

BACKGROUND: Acute liver failure is associated with a marked depletion of intrahepatic adenosine 5'-triphosphate (ATP), a compound required for the maintenance of hepatic function and enhanced hepatic regeneration. AIM: The aim of this study was to test the safety and efficacy of exogenous ATP at various doses in a rat model of acute liver failure. METHODS: Adult male Sprague-Dawley rates (n = 56) received an intraperitoneal dose (1.0 g/kg) of the potent hepatotoxin D: -galactosamine (D: -galN). Thereafter, rats were divided into groups that received saline (n = 18), low (n = 8), moderate (n = 18) or high (n = 12) doses of ATP for 7 days. RESULTS: There was an inverse correlation between ATP dose and survival such that rats treated with low dose ATP had the highest survival rate (50%) compared to moderate (39%) and high (17%) dose treated groups. However, survival in all treated groups was similar (P = 0.085) to that of controls (45%). Liver biochemistry, regenerative activity and ATP levels were similar in the highest survival group (low dose ATP) versus controls. CONCLUSION: These findings suggest that exogenous ATP does not improve and indeed at high doses may impair survival in rats with acute liver failure. Further studies involving a wider range of ATP doses and different routes and frequency of ATP administration are required to determine whether exogenous ATP has therapeutic value in the treatment of acute liver failure.


Assuntos
Trifosfato de Adenosina/administração & dosagem , Falência Hepática Aguda/tratamento farmacológico , Trifosfato de Adenosina/toxicidade , Animais , Espectroscopia de Ressonância Magnética , Masculino , Isótopos de Fósforo , Ratos , Ratos Sprague-Dawley
14.
Acta Biochim Biophys Sin (Shanghai) ; 39(6): 423-30, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17558447

RESUMO

Polyamine biosynthesis is controlled primarily by ornithine decarboxylase (ODC) and S-adenosylmethionine decarboxylase (AdoMetDC). Antisense sequences of ODC and AdoMetDC genes were cloned into an adenoviral vector (named Ad-ODC-AdoMetDCas). To evaluate the effects of recombinant adenovirus Ad-ODC-AdoMetDCas that can simultaneously express both antisense ODC and AdoMetDC, the human lung cancer cell line A-549 was infected with Ad-ODC-AdoMetDCas or the control vector. Viable cell counting, determination of polyamine concentrations, cell cycle analysis, and Matrigel invasion assays were carried out to assess the properties of tumor growth and invasiveness. Our study showed that adenovirus-mediated antisense ODC and AdoMetDC expression inhibits tumor cell growth through blocking the polyamine synthesis pathway. Tumor cells were arrested at the G1 phase after gene transfer and the invasiveness was reduced. It suggested that the recombinant adenovirus Ad-ODC-AdoMetDCas might be a new anticancer reagent in the treatment of lung cancers.


Assuntos
Adenosilmetionina Descarboxilase/metabolismo , Adenoviridae/genética , Vetores Genéticos/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Oligodesoxirribonucleotídeos Antissenso/metabolismo , Ornitina Descarboxilase/metabolismo , Adenosilmetionina Descarboxilase/química , Adenosilmetionina Descarboxilase/genética , Adenoviridae/química , Clonagem Molecular , Colágeno/química , Colágeno/metabolismo , Combinação de Medicamentos , Fase G1/fisiologia , Técnicas de Transferência de Genes , Terapia Genética , Vetores Genéticos/química , Humanos , Laminina/química , Laminina/metabolismo , Luciferases/metabolismo , Neoplasias Pulmonares/genética , Invasividade Neoplásica/fisiopatologia , Oligodesoxirribonucleotídeos Antissenso/química , Ornitina Descarboxilase/química , Ornitina Descarboxilase/genética , Poliaminas/química , Poliaminas/metabolismo , Regiões Promotoras Genéticas/genética , Proteoglicanas/química , Proteoglicanas/metabolismo , Transfecção/métodos , Transgenes , Células Tumorais Cultivadas
15.
Hepatology ; 45(3): 735-45, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17326191

RESUMO

UNLABELLED: To determine whether hepatocyte membrane potential differences (PDs) are depolarized in human HCC and whether depolarization is associated with changes in GABAA receptor expression, hepatocyte PDs and gamma-aminobutyric acid (GABA)A receptor messenger RNA (mRNA) and protein expression were documented in HCC tissues via microelectrode impalement, real-time reverse-transcriptase polymerase chain reaction, and Western blot analysis, respectively. HCC tissues were significantly depolarized (-19.8+/-1.3 versus -25.9+/-3.2 mV, respectively [P<0.05]), and GABAA-beta3 expression was down-regulated (GABAA-beta3 mRNA and protein expression in HCC; 5,693+/-1,385 and 0.29+/-0.11 versus 11,046+/-4,979 copies/100 mg RNA and 0.62+/-0.16 optical density in adjacent tumor tissues, respectively [P=0.002 and P<0.0001, respectively]) when compared with adjacent nontumor tissues. To determine the physiological relevance of the down-regulation, human malignant hepatocytes deficient in GABAA-beta3 receptor expression (Huh-7 cells) were transfected with GABAA-beta3 complementary DNA (cDNA) or vector alone and injected into nu/nu nude mice (n=16-17 group). Tumors developed after a mean (+/-SD) of 51+/-6 days (range: 41-60 days) in 7/16 (44%) mice injected with vector-transfected cells and 70+/-12 days (range: 59-86 days) in 4/17 (24%) mice injected with GABAA-beta3 cDNA-transfected cells (P<0.005). CONCLUSION: The results of this study indicate that (1) human HCC tissues are depolarized compared with adjacent nontumor tissues, (2) hepatic GABAA-beta3 receptor expression is down-regulated in human HCC, and (3) restoration of GABAA-beta3 receptor expression results in attenuated in vivo tumor growth in nude mice.


Assuntos
Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/fisiopatologia , Hepatócitos/fisiologia , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/fisiopatologia , Potenciais da Membrana/fisiologia , Receptores de GABA-A/metabolismo , Adolescente , Adulto , Animais , Carcinoma Hepatocelular/genética , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Hepáticas/genética , Masculino , Camundongos , Camundongos Nus , Pessoa de Meia-Idade , RNA Mensageiro/metabolismo , Receptores de GABA-A/genética , ATPase Trocadora de Sódio-Potássio/genética , ATPase Trocadora de Sódio-Potássio/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
16.
Platelets ; 17(3): 178-84, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16702045

RESUMO

Excessive platelet activation and accumulation can lead to vessel occlusion and thus present major therapeutic challenges in cardiovascular medicine. Apyrase, an ecto-enzyme with ADPase and ATPase activities, rapidly metabolizes ADP and ATP released from platelets and endothelial cells, thereby reducing platelet activation and recruitment. In the present study, we expressed a 68-kDa recombinant mosquito (Aedes aegypti) salivary apyrase using a baculovirus/insect cell expression system and purified it to homogeneity using anion-exchange chromatography on a large scale. A yield of 18 mg of purified recombinant apyrase was obtained from 1 litre of the medium. Kinetic analysis indicated that the recombinant apyrase had a K(m) of 12.5 microM for ADP and a K(m) of 15.0 microM for ATP. The recombinant apyrase inhibited ADP-, collagen- and thrombin-induced human platelet aggregation in a dose-dependent manner, indicating that the recombinant protein retained nucleotidase activity in a whole cell system, which suggests that it may serve as a therapeutic agent for inhibition of platelet-mediated thrombosis.


Assuntos
Aedes/enzimologia , Apirase/biossíntese , Inibidores da Agregação Plaquetária/química , Antagonistas do Receptor Purinérgico P2 , Proteínas Recombinantes/biossíntese , Proteínas e Peptídeos Salivares/biossíntese , Animais , Apirase/química , Apirase/isolamento & purificação , Baculoviridae/genética , Expressão Gênica/genética , Vetores Genéticos , Humanos , Agregação Plaquetária/efeitos dos fármacos , Inibidores da Agregação Plaquetária/uso terapêutico , Piridinas/uso terapêutico , Proteínas Recombinantes/química , Proteínas Recombinantes/uso terapêutico , Proteínas e Peptídeos Salivares/química , Proteínas e Peptídeos Salivares/uso terapêutico
17.
Hepatology ; 42(4): 871-9, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16175609

RESUMO

Liver fatty acid binding protein (L-FABP) contains amino acids that are known to possess antioxidant function. In this study, we tested the hypothesis that L-FABP may serve as an effective endogenous cytoprotectant against oxidative stress. Chang liver cells were selected as the experimental model because of their undetectable L-FABP mRNA level. Full-length L-FABP cDNA was subcloned into the mammalian expression vector pcDNA3.1 (pcDNA-FABP). Chang cells were stably transfected with pc-DNA-FABP or vector (pcDNA3.1) alone. Oxidative stress was induced by incubating cells with 400 micromol/L H2O2 or by subjecting cells to hypoxia/reoxygenation. Total cellular reactive oxygen species (ROS) was determined using the fluorescent probe DCF. Cellular damage induced by hypoxia/reoxygenation was assayed by lactate dehydrogenase (LDH) release. Expression of L-FABP was documented by regular reverse transcription polymerase chain reaction (RT-PCR), real-time RT-PCR, and Western blot. The pcDNA-FABP-transfected cells expressed full-length L-FABP mRNA, which was absent from vector-transfected control cells. Western blot showed expression of 14-kd L-FABP protein in pcDNA-FABP-transfected cells, but not in vector-transfected cells. Transfected cells showed decreased DCF fluorescence intensity under oxidative stress (H2O2 and hypoxia/reoxygenation) conditions versus control in inverse proportion to the level of L-FABP expression. Lower LDH release was observed in the higher L-FABP-expressed cells in hypoxia/reoxygenation experiments. In conclusion, we successfully transfected and cloned a Chang liver cell line that expressed the L-FABP gene. The L-FABP-expressing cell line had a reduced intracellular ROS level versus control. This finding implies that L-FABP has a significant role in oxidative stress.


Assuntos
Antioxidantes/metabolismo , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Hepatócitos/metabolismo , Transfecção/métodos , Apoptose , Carcinoma Hepatocelular , Linhagem Celular Tumoral , DNA Complementar , Proteínas de Ligação a Ácido Graxo , Glutationa/metabolismo , Hepatócitos/citologia , Hepatócitos/fisiologia , Humanos , Peróxido de Hidrogênio/farmacologia , Hipóxia/metabolismo , Neoplasias Hepáticas , Oxidantes/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Traumatismo por Reperfusão/metabolismo , Superóxido Dismutase/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
18.
Hepatology ; 40(5): 1144-50, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15382152

RESUMO

Metastases rarely occur in human livers with cirrhosis in clinical studies. We postulated that this phenomenon would also occur in experimental cirrhosis. Cirrhosis was established in C57BL/6 mice by carbon tetrachloride (CCl(4)) gastrogavage. B16F1 melanoma cells were injected into the mesenteric vein to induce hepatic metastases. Contrary to our postulate, there was greater than 4-fold increase in metastasis in animals with cirrhosis compared to controls. Intravital videomicroscopy showed that the hepatic sinusoids were narrower and more tumor cells were retained in the terminal portal vein (TPV) in cirrhotic livers. Immunohistochemistry demonstrated that the expression of vascular adhesion molecules was significantly increased in cirrhosis. Using confocal microscopy and the fluorescent nitric oxide (NO) probe 4,5-diaminofluorescein diacetate, a significantly lower level of NO release was detected in livers with cirrhosis both in basal conditions and after tumor cell arrest. Eight hours after mesenteric vein tumor cell injection, the percentage of apoptotic tumor cells in the sinusoids was 17% +/- 2% in livers with cirrhosis and 30% +/- 5% in normal livers. More mitotic and Ki-67 labeled tumor cells were seen in livers with cirrhosis. In conclusion, the changes in architecture and adhesion molecule expression in livers with cirrhosis may cause more tumor cells to arrest in the TPV. Lower levels of NO production may reduce apoptosis of B16F1 cells in livers with cirrhosis. As a result, these changes may promote the growth of metastasis in this cirrhotic model.


Assuntos
Cirrose Hepática Experimental/complicações , Neoplasias Hepáticas/complicações , Neoplasias Hepáticas/secundário , Melanoma Experimental/complicações , Melanoma Experimental/secundário , Animais , Apoptose , Divisão Celular , Linhagem Celular Tumoral , Feminino , Fluoresceína , Imuno-Histoquímica , Indicadores e Reagentes , Fígado/patologia , Cirrose Hepática Experimental/metabolismo , Cirrose Hepática Experimental/patologia , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/fisiopatologia , Melanoma Experimental/patologia , Melanoma Experimental/fisiopatologia , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Confocal , Microscopia de Vídeo , Óxido Nítrico/metabolismo , Molécula 1 de Adesão de Célula Vascular/metabolismo
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