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Development of highly porous and robust HOFs for high-pressure methane and hydrogen storage remains a grand challenge due to the fragile nature of hydrogen bonds. Herein, we report a strategy of constructing double-walled framework to target highly porous and robust HOF (ZJU-HOF-5a) for extraordinary CH4 and H2 storage. ZJU-HOF-5a features a minimized twofold interpenetration with double-walled structure, in which multiple supramolecular interactions are existed between the interpenetrated walls. This structural configuration can notably enhance the framework robustness while maintaining its high porosity, affording one of the highest gravimetric and volumetric surface areas of 3102 m2 g-1 and 1976 m2 cm-3 among the reported HOFs so far. ZJU-HOF-5a exhibits an extremely high volumetric H2 uptake of 43.6 g L-1 at 77 K/100 bar and working capacity of 41.3 g L-1 under combined swing conditions, and also impressive methane storage performance with a 5-100 bar working capacity of 187 (or 159) cm3 cm-3 at 270 K (or 296 K). SCXRD studies on CH4-loaded ZJU-HOF-5a reveal that abundant supramolecular binding sites combined with ultrahigh porosities account for its high CH4 storage capacities. Combined with high stability, super-hydrophobicity, and easy-recovery, ZJU-HOF-5a is placed among the most promising materials for H2 and CH4 storage applications.
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Introduction: The Tarlov cysts are pathological enlargements of the cerebrospinal fluid spaces between the endoneurium and perineurium, which can cause intolerable sciatic pain, motor impairment of lower limbs, and bladder/bowel dysfunction. Currently, the treatment results are unsatisfactory due to the low cure rates and extensive surgical trauma. Thus, there is an ongoing exploration of surgical techniques for Tarlov treatment. In the current study, we present a novel neuroendoscopic-assisted technique that combines the fenestration, leakage sealing, and tamponade of the Tarlov cyst. Methods: Between January 2020 and December 2021, a total of 32 Tarlov patients were enrolled and received neuroendoscopic-assisted surgery. Their pre- and post-surgical Visual Analogue Scale (VAS) scores, major complaints, and MR imaging were recorded for comparison. Results: 27 of 32 patients (84.4%) patients demonstrated immediate pain relief as their VAS scores decreased from 5.6 ± 1.5 to 2.5 ± 1.1 (p < 0.01) on the first day after surgery. At the 3-month follow-up, the patients' average VAS score continued to decrease (1.94 ± 0.8). Meanwhile, saddle paresthesia, urinary incontinence, and constipation were relieved in 6 (50%), 4 (80%), and 5 (41.7%), respectively, according to patients self-report. No surgical-related complication was observed in any of the cases. Discussion: We conclude that neuroendoscopic-assisted surgery is an effective surgical method for symptomatic Tarlov cysts with minimized complications.
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6-methoxydihydrosanguinarine (6-MS), a natural benzophenanthridine alkaloid extracted from Macleaya cordata (Willd.) R. Br, has shown to trigger apoptotic cell death in cancer cells. However, the exact mechanisms involved have not yet been clarified. The current study reveals the underlying mechanisms of 6-MS-induced cytotoxicity in hepatocellular carcinoma (HCC) cells and investigates whether 6-MS sensitizes TNF-related apoptosis inducing ligand (TRAIL)-induced apoptosis. 6-MS was shown to suppress cell proliferation and trigger cell cycle arrest, DNA damage, and apoptosis in HCC cells. Mechanisms analysis indicated that 6-MS promoted reactive oxygen species (ROS) generation, JNK activation, and inhibits EGFR/Akt signaling pathway. DNA damage and apoptosis induced by 6-MS were reversed following N-acetyl-l-cysteine (NAC) treatment. The enhancement of PARP cleavage caused by 6-MS was abrogated by pretreatment with JNK inhibitor SP600125. Furthermore, 6-MS enhanced TRAIL-mediated HCC cells apoptosis by upregulating the cell surface receptor DR5 expression. Pretreatment with NAC attenuated 6-MS-upregulated DR5 protein expression and alleviated cotreatment-induced viability reduction, cleavage of caspase-8, caspase-9, and PARP. Overall, our results suggest that 6-MS exerts cytotoxicity by modulating ROS generation, EGFR/Akt signaling, and JNK activation in HCC cells. 6-MS potentiates TRAIL-induced apoptosis through upregulation of DR5 via ROS generation. The combination of 6-MS with TRAIL may be a promising strategy and warrants further investigation.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patologia , Benzofenantridinas/farmacologia , Benzofenantridinas/uso terapêutico , Neoplasias Hepáticas/patologia , Regulação para Cima , Espécies Reativas de Oxigênio/metabolismo , Linhagem Celular Tumoral , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ligante Indutor de Apoptose Relacionado a TNF/farmacologia , Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Apoptose , Receptores ErbB/genéticaRESUMO
OBJECTIVE: To identify specific Chinese medicines (CMs) that may benefit patients with gastroesophageal reflux disease (GERD), and explore the action mechanism. METHODS: Domestic and foreign literature on the treatment of GERD with CMs was searched and selected from China National Knowledge Infrastructure, China Science and Technology Journal Database, Wanfang Database, and PubMed from October 1, 2011 to October 1, 2021. Data from all eligible articles were extracted to establish the database of CMs for GERD. Apriori algorithm of data mining techniques was used to analyze the rules of herbs selection and core Chinese medicine formulas were identified. A system pharmacology approach was used to explore the action mechanism of these medicines. RESULTS: A total of 278 prescriptions for GERD were analyzed, including 192 CMs. Results of Apriori algorithm indicated that Evodiae Fructus and Coptidis Rhizoma were the highest confidence combination. A total of 32 active ingredients and 66 targets were screened for the treatment of GERD. Enrichment analysis showed that the mechanisms of action mainly involved pathways in cancer, fluid shear stress and atherosclerosis, advanced glycation end product (AGE), the receptor for AGE signaling pathway in diabetic complications, bladder cancer, and rheumatoid arthritis. CONCLUSION: Evodiae Fructus and Coptidis Rhizoma are the core drugs in the treatment of GERD and the potential mechanism of action of these medicines includes potential target and pathways.
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Medicamentos de Ervas Chinesas , Refluxo Gastroesofágico , Humanos , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Medicina Tradicional Chinesa , Farmacologia em Rede , Mineração de Dados , Refluxo Gastroesofágico/tratamento farmacológicoRESUMO
BACKGROUND: Mechanical obstruction is the most common cause of shunt failure for hydrocephalic patients. However, the diagnosis is extremely challenging and often requires invasive testing methods. Thus, a simple and non-invasive technique is in urgent need to predict the intracranial pressure (ICP) of hydrocephalic patients during their post-surgical follow-up, which could help neurosurgeons to determine the conditions of the shunt system. MATERIALS AND METHODS: Two groups of patients were enrolled in the current study. In group I, patients were enrolled as they were diagnosed with high ICP hydrocephalus and received shunt surgery. The shunt valve pressures were taken for their post-surgical ICP. Meanwhile, the participants of group II exhibited abnormally increased lumbar puncture opening pressure (LPOP; from 180 to 400 mmH2O). Both the ICP and LPOP were used to match with their corresponding tympanic membrane temperature (TMT). RESULTS: When patients' ICP were in the normal range (group I, from 50 to 180 mmH2O), the TMT correlated with ICP in a linear regression model (R2 = 0.59, p < 0.001). Interestingly, when patients exhibited above-normal ICP (LPOP was from 180 to 400 mmH2O), their TMT fit well with the ICP in a third-order polynomial regression (R2 = 0.88). When the ICP was 287.98 mmH2O, the TMT approached the vertex, which was 38.54 °C. Based on this TMT-ICP algorithm, we invented a non-invasive ICP monitor system. Interestingly, a tight linear correlation was detected between the ICP data drawn from the non-invasive device and Codman ICP monitoring system (R2 = 0.93, p < 0.01). CONCLUSIONS: We believe the TMT-ICP algorithm (the Y-Jiang model) could be used for preliminary prediction of shunt malfunction as well as monitoring ICP changes.
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Hidrocefalia , Pressão Intracraniana , Humanos , Invenções , Hidrocefalia/diagnóstico , Hidrocefalia/cirurgia , Monitorização Fisiológica , Derivações do Líquido CefalorraquidianoRESUMO
PURPOSE: To evaluate the effect of AMD3100 treatment to cholangiocarcinoma by analyzing the relationship between them, and provide experimental evidence for whether AMD3100 can become a clinical treatment drug for cholangiocarcinoma. MATERIALS AND METHODS: Cholangiocarcinoma RBE cell lines were used in this study. MTT cell proliferation test was used for evaluating the effect of gemcitabine and AMD3100 to cell. CXCR4, N-cadherin, VEGF-C and MMP-9 were detect by RT-PCR and western. Transwell was used for evaluating the invasion effect. RESULTS: We demonstrated that as the concentration of gemcitabine increasing from 0.33, 3.33 to 33.33 uM, the cell survival rate was 76.65%, 71.40%, 52.25%, respectively. RT-PCR and Western blot that gemcitabine could affect the expression of CXCR4 protein and the level of mRNA transcription in a dose-dependent manner. N-cadherin VEGF-C, MMP-9 mRNA transcription level showed a significant upward trend in gemcitabine group. In Transwell test, the number of cells in the gemcitabine group was significantly higher than that in the no-medication group (p < .05), the AMD3100 group and the combination group of gemcitabine and AMD3100, the difference between the no-medication group and the AMD3100 monotherapy group was not significant, and the combination group was between them. CONCLUSIONS: This study showed that gemcitabine significantly inhibited the growth of cholangiocarcinoma RBE cells in a dose-dependent manner, and gemcitabine can affect the expression of CXCR4, N-cadherin, VEGF-C, MMP-9 protein and mRNA. Cell invasion and metastasis-related factors decreased after AMD3100 combined with gemcitabine.
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Neoplasias dos Ductos Biliares , Colangiocarcinoma , Benzilaminas , Neoplasias dos Ductos Biliares/tratamento farmacológico , Neoplasias dos Ductos Biliares/genética , Ductos Biliares Intra-Hepáticos , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Quimiocina CXCL12 , Colangiocarcinoma/tratamento farmacológico , Colangiocarcinoma/genética , Ciclamos , Desoxicitidina/análogos & derivados , Humanos , Invasividade Neoplásica , Receptores CXCR4/genética , GencitabinaRESUMO
LF11-322 (PFWRIRIRR-NH2) (PFR peptide), a nine amino acid-residue peptide fragment derived from human lactoferricin, possesses potent cytotoxicity against bacteria. We report here the discovery and characterization of its antitumor activity in leukemia cells. PFR peptide inhibited the proliferation of MEL and HL-60 leukemia cells by inducing cell death in the absence of the classical features of apoptosis, including chromatin condensation, Annexin V staining, Caspase activation and increase of abundance of pro-apoptotic proteins. Instead, necrotic cell death as evidenced by increasing intracellular PI staining and LDH release, inducing membrane disruption and up-regulating intracellular calcium level, was observed following PFR peptide treatment. In addition to necrotic cell death, PFR peptide also induced G0/G1 cell cycle arrest. Moreover, PFR peptide exhibited favorable antitumor activity and tolerability in vivo. These findings thus provide a new clue of antimicrobial peptides as a potential novel therapy for leukemia.
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Peptídeos Catiônicos Antimicrobianos/farmacologia , Lactoferrina/química , Necrose/induzido quimicamente , Peptídeos/farmacologia , Animais , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Feminino , Células HL-60 , Hemólise/efeitos dos fármacos , Humanos , Leucemia/patologia , CamundongosRESUMO
Regulatory T (Treg) cells are potent suppressors that maintain immune homeostasis. Accumulation of Treg can inhibit effective immune responses in cancer patients, leading to tumor development and progression. Despite direct cytotoxicity, several chemotherapeutic drugs have been reported to deplete Treg cells for better prognosis for cancer patients. Treg cells are a heterogenous population with at least three different subsets, nonsuppressive, resting, and activated Treg cells. However, the characteristics of Treg cell subsets in lung cancer patients and how chemotherapy affects Treg cells remain elusive. In this study, we first analyzed Treg cell subsets in peripheral blood samples from 40 nonsmall cell lung cancer (NSCLC) patients and 20 healthy donors. Treg cells, specifically activated Treg cell subset, significantly increased in patients with NSCLC. Compared to nonsuppressive Treg cells, activated Treg cells expressed higher level of CD39 and predominantly produced inhibitory cytokines. In vitro assay showed that docetaxel reduced all three subsets of Treg cells. More importantly, we found docetaxel-based chemotherapy significantly decreased all three Treg subsets after 4 cycles of treatment in 17 NSCLC patients. Taken together, this study revealed dynamic changes of various Treg cell subsets in NSCLC patients before and after chemotherapy, providing activated Treg cells as a potential target for chemotherapy.
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Antineoplásicos Fitogênicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Depleção Linfocítica , Linfócitos T Reguladores/efeitos dos fármacos , Taxoides/uso terapêutico , Idoso , Carcinoma Pulmonar de Células não Pequenas/imunologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Estudos de Casos e Controles , Linhagem da Célula/imunologia , Docetaxel , Feminino , Humanos , Imunofenotipagem , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Linfócitos T Reguladores/classificação , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/patologiaRESUMO
BACKGROUND: Mucous hypersecretion increases asthma morbidity and mortality. Tumor necrosis factor a (TNF-a) levels are elevated in bronchoalveolar fluid, sputum, and monocyte membranes in some patients with asthma. Anti-TNF-a decreased asthma exacerbations and improved forced expiratory volume in 1 second in these patients. Whether anti-TNF-a reduces mucous cell metaplasia or hyperplasia has not been evaluated. OBJECTIVE: To investigate the role of anti-TNF-alpha in mucous hypersecretion. METHODS: BALB/c mice sensitized intraperitoneally and challenged intratracheally with ovalbumin were treated with 250 microg of anti-TNF-alpha before ovalbumin sensitization and challenge or before only ovalbumin challenge. Control groups were sham treated. The tumor necrosis factor receptor (TNFR) mice (TNFR-/- and TNFR+/+) were identically sensitized and challenged. Seventy-two hours after the final challenge, the airway pressure time index (APTI), which measures airway hyperresponsiveness, was recorded. Mucous cell metaplasia was accessed by quantitative polymerase chain reaction for MUC-5AC (the epithelial cell mucous-inducing gene) and the percentage of periodic acid-Schiff (PAS) staining of bronchial epithelial cells. A human airway cell line (constitutively expressing MUC-5AC) was pretreated with a NF-kappaB inhibitor before TNF-alpha culture. RESULTS: The mean (SE) fold change of MUC-5AC expression (compared with naive controls), the percentage of PAS-positive bronchiole epithelial cells, and the APTI decreased in BALB/c mice treated with anti-TNF-alpha before sensitization and challenge (4.9 [1.14], P = .007; 28.9% [6.8%], P < .001; and 545.8 [104.5] cm H2O/s, P < .001, respectively) and before challenge alone (9.3 [1.8], P = .03; 43.6% [10.7%], P = .009; and 896.8 [81.23] cm H2O/s, P = .06, respectively) compared with sham-treated mice (20.9 [3.9], 82.4% [1.8%], and 1,055 [30.6] cm H20/s, respectively). MUC-5AC expression decreased in ovalbumin sensitized or challenged TNFR-/- (2.41 [0.4]) compared with ovalbumin sensitized or challenged TNFR+/+ mice (18.4 [2.5], P < .001). TNF-alpha-induced MUC-5AC expression in human airway culture significantly decreased with pretreatment of a NF-kappaB inhibitor. CONCLUSIONS: Anti-TNF-alpha treatment reduces airway mucous cell metaplasia in a mouse model of asthma, which may in part underlie its beneficial effect as asthma therapy.
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Anticorpos Monoclonais/farmacologia , Asma/terapia , Mucina-5AC/biossíntese , Mucosa Respiratória/fisiologia , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Animais , Asma/genética , Asma/imunologia , Líquido da Lavagem Broncoalveolar/citologia , Linhagem Celular , Feminino , Expressão Gênica/efeitos dos fármacos , Expressão Gênica/imunologia , Histocitoquímica , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Mucina-5AC/genética , Ovalbumina/imunologia , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Receptores do Fator de Necrose Tumoral/imunologia , Mucosa Respiratória/efeitos dos fármacos , Mucosa Respiratória/imunologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Necrose Tumoral alfa/imunologiaRESUMO
BACKGROUND: Despite widespread agreement that estrogens are involved in the etiology of human breast cancer, there is uncertainty as to the molecular mechanisms of estrogen action in early development of breast cancer. MATERIALS AND METHODS: MCF10AT3B cells, a cell line derived from a xenograft model of human proliferative breast disease, were used to study the estrogen-stimulated malignant progression of neoplastigenic mammary epithelial cells. A stable cell line was established from MCF10AT3B cells that ectopically expresses the retinoblastoma suppressor (Rb)-associated protein 46 (RbAp46), a component of the histone modifying and remodeling complexes. Western blot and in vitro and in vivo growth assays were used to study the effects of constitutive RbAp46 expression on estrogen-stimulated cell proliferation. RESULTS: Estrogen treatment downregulated RbAp46 expression in MCF10AT3B cells. Constitutive RbAp46 expression inhibited estrogen-stimulated cell growth in vitro. In nude mice, RbAp46 expression strongly suppressed estrogen-stimulated tumorigenesis of MCF10AT3B cells. In RbAp46-expressing tumors, beta-catenin protein was highly phosphorylated and the steady state levels of beta-catenin protein were significantly reduced. CONCLUSION: RbAp46 plays an important role in the regulation of mitogenic estrogen signaling and dysregulated RbAp46 expression may contribute to estrogen-stimulated breast cancer development.
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Neoplasias da Mama/induzido quimicamente , Neoplasias da Mama/patologia , Proteínas de Transporte/biossíntese , Estradiol/farmacologia , Antagonistas de Estrogênios/metabolismo , Proteínas Nucleares/biossíntese , Animais , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Proteínas de Transporte/genética , Processos de Crescimento Celular/efeitos dos fármacos , Processos de Crescimento Celular/fisiologia , Linhagem Celular Tumoral , Progressão da Doença , Regulação para Baixo/efeitos dos fármacos , Células Epiteliais/patologia , Feminino , Humanos , Camundongos , Camundongos Nus , Proteínas Nucleares/genética , Fosforilação , Proteína 7 de Ligação ao Retinoblastoma , Transfecção , Transplante Heterólogo , beta Catenina/metabolismoRESUMO
BACKGROUND: The effect of ageing on several pathologic features of allergic asthma (pulmonary inflammation, eosinophilia, mucus hypersecretion), and their relationship with airway hyperresponsiveness (AHR) is not well characterized. OBJECTIVE: To evaluate lung inflammation, mucus metaplasia and AHR in relationship with age in murine models of allergic asthma comparing young and older mice. METHODS: Young (6 weeks) and older (6, 12, 18 months) BALB/c mice were sensitized and challenged with ovalbumin (OVA). AHR and bronchoalveolar fluid (BALF), total inflammatory cell count and differential were measured. To evaluate mucus metaplasia, quantitative PCR for the major airway mucin-associated gene, MUC-5AC, from lung tissue was measured, and lung tissue sections stained with periodic acid-Schiff (PAS) for goblet-cell enumeration. Lung tissue cytokine gene expression was determined by quantitative PCR, and systemic cytokine protein levels by ELISA from spleen-cell cultures. Antigen-specific serum IgE was determined by ELISA. RESULTS: AHR developed in both aged and young OVA-sensitized/challenged mice (OVA mice), and was more significantly increased in young OVA mice than in aged OVA mice. However, BALF eosinophil numbers were significantly higher, and lung histology showed greater inflammation in aged OVA mice than in young OVA mice. MUC-5AC expression and numbers of PAS+ staining bronchial epithelial cells were significantly increased in the aged OVA mice. All aged OVA mice had increased IL-5 and IFN-gamma mRNA expression in the lung and IL-5 and IFN-gamma protein levels from spleen cell cultures compared with young OVA mice. OVA-IgE was elevated to a greater extent in aged OVA mice. CONCLUSIONS: Although pulmonary inflammation and mucus metaplasia after antigen sensitization/challenge occurred to a greater degree in older mice, the increase in AHR was significantly less compared with younger OVA mice. Antigen treatment produced a unique cytokine profile in older mice (elevated IFN-gamma and IL-5) compared with young mice (elevated IL-4 and IL-13). Thus, the airway response to inflammation is lessened in ageing animals, and may represent age-associated events leading to different phenotypes in response to antigen provocation.
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Envelhecimento/imunologia , Hiper-Reatividade Brônquica/imunologia , Líquido da Lavagem Broncoalveolar/citologia , Pneumonia/imunologia , Animais , Asma/imunologia , Asma/fisiopatologia , Linfócitos B/imunologia , Hiper-Reatividade Brônquica/induzido quimicamente , Líquido da Lavagem Broncoalveolar/imunologia , Ensaio de Imunoadsorção Enzimática , Eosinofilia/imunologia , Feminino , Expressão Gênica , Interferon gama/biossíntese , Interleucina-13/biossíntese , Interleucina-4/biossíntese , Interleucina-5/biossíntese , Metaplasia , Camundongos , Camundongos Endogâmicos BALB C , Mucina-5AC , Mucinas/biossíntese , Muco/imunologia , Ovalbumina/efeitos adversos , Pneumonia/patologia , Reação em Cadeia da Polimerase , Linfócitos T/imunologiaRESUMO
BACKGROUND: Hypersecretion of mucus plays an important role in the pathogenesis and severity of asthma. The primary proteins in mucus are mucin glycoproteins; MUC-5AC is the primary airway mucin gene. The calcium chloride-activated channel gene hCLCA1 (gob-5 in the mouse) has been suggested to increase MUC-5AC gene expression, and both are increased in asthmatic patients and murine models. TNF-alpha increases the expression of these genes in vitro but has not been investigated in vivo. OBJECTIVE: We sought to determine whether TNF-alpha increases gene expression of gob-5 and MUC-5AC and induces mucus cell metaplasia in vivo. METHODS: Naive BALB/c mice received 50 ng of recombinant murine TNF-alpha (rmTNF-alpha) intratracheally daily for 1, 2, or 3 weeks; another group received the same dose of intratracheal rmTNF-alpha daily for 3 weeks and then alternate-day treatment for 3 additional weeks (total of 6 weeks). AKR mice received 50 ng of rmTNF-alpha intratracheally for 3 or 6 weeks daily. Naive nontreated mice were used as control animals. Airway gene products for gob-5 and MUC-5AC were determined by means of real-time PCR. Lung tissue sections were stained with periodic acid-Schiff/Alcian blue to assess mucus cell metaplasia. RESULTS: rmTNF-alpha significantly increased gene expression of airway gob-5 and MUC-5AC after 2 weeks in the BALB/c mice. There was noticeable mucus staining in all mice treated for at least 3 weeks with TNF-alpha and in 80% of the mice receiving 2 weeks of treatment. After 3 weeks of treatment, the AKR mice also showed increased gob-5 expression. CONCLUSIONS: This study demonstrates for the first time that TNF-alpha alone in vivo is sufficient to increase airway mucus gene expression in 2 murine strains.
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Canais de Cloreto/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Pulmão/efeitos dos fármacos , Mucinas/genética , Mucoproteínas/genética , Muco/efeitos dos fármacos , Traqueia/efeitos dos fármacos , Fator de Necrose Tumoral alfa/farmacologia , Animais , Asma/etiologia , Temperatura Corporal/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Hiper-Reatividade Brônquica/etiologia , Citocinas/biossíntese , Pulmão/metabolismo , Pulmão/patologia , Metaplasia , Camundongos , Camundongos Endogâmicos AKR , Camundongos Endogâmicos BALB C , Mucina-5AC , Muco/metabolismo , Proteínas Recombinantes/farmacologia , Traqueia/metabolismoRESUMO
The Wilms' tumor suppressor gene, wt1, encodes a zinc-finger protein, WT1, that functions as a potent inhibitor of cell growth. The findings that expression levels of WT1 were down-regulated in breast cancer cell lines and in subsets of primary breast tumors led us to investigate the possible role of WT1 in tumorigenesis of breast cancer. We have established stable cell lines from a breast cancer cell line MDA-MB-231 to express exogenous WT1, and investigated the ability of WT1 to inhibit the transformed phenotype of MDA-MB-231 cells. We found that WT1 suppressed clonal growth of MDA-MB-231 cells in soft-agar and inhibited tumor growth of these cells in nude mice. We also found that the steady state levels of beta-catenin protein and the transcription activity of beta-catenin/Tcf signaling pathway were dramatically decreased in WT1-transfected cells. This decrease of beta-catenin was associated with increased levels of beta-catenin phosphorylation. Furthermore, the expression levels of GSK-3 beta, the kinase that phosphorylates beta-catenin and signals its degradation, were up-regulated in WT1-transfected cells. The results suggest that WT1 inhibits the transformed phenotype of breast cancer cells and down-regulates the beta-catenin/TCF signaling pathway through destabilization of beta-catenin.
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Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Proteínas do Citoesqueleto/fisiologia , Transativadores/fisiologia , Proteínas WT1/fisiologia , Neoplasias da Mama/metabolismo , Divisão Celular/fisiologia , Linhagem Celular Tumoral , Proteínas do Citoesqueleto/metabolismo , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/fisiologia , Regulação para Baixo , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Genes do Tumor de Wilms , Quinase 3 da Glicogênio Sintase/biossíntese , Quinase 3 da Glicogênio Sintase/genética , Quinase 3 da Glicogênio Sintase/metabolismo , Glicogênio Sintase Quinase 3 beta , Humanos , Fator 1 de Ligação ao Facilitador Linfoide , Transdução de Sinais/fisiologia , Transativadores/metabolismo , Fatores de Transcrição/metabolismo , Fatores de Transcrição/fisiologia , Transfecção , Regulação para Cima , Proteínas WT1/biossíntese , Proteínas WT1/genética , beta CateninaRESUMO
The retinoblastoma (Rb) suppressor associated protein 46 (RbAp46) is a subunit of chromatin modifying and remodeling complexes. Previously, we found that RbAp46 functions as a potent growth inhibitor. It is also a downstream effector of the Wilms' tumor suppressor, WT1. The findings that expression levels of WT1 were down-regulated in breast cancer cell lines and in subsets of primary breast tumors led us to investigate the possible role of RbAp46 in breast cancer tumorigenesis. Here, we found that RbAp46 expression levels were decreased in five established breast cancer cell lines compared to a normal mammary gland epithelial cell line. To investigate the effect of constitutive expression of RbAp46 on the transformed phenotypes of breast cancer cells, we established stable cell lines that constitutively express exogenous RbAp46 using three breast cancer cell lines, MCF-7, MDA-MB-231 and MDA-MB-436. We have found that RbAp46 expression suppressed colony formation of these breast cancer cells in soft-agar, and inhibited tumor formation of these cells in nude mice. Our data demonstrated that constitutive RbAp46 expression suppresses the transformed phenotypes of breast cancer cells, and suggested that dysregulation of RbAp46 expression may contribute to breast cancer tumorigenesis.
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Neoplasias da Mama/patologia , Proteínas de Transporte/fisiologia , Transformação Celular Neoplásica/patologia , Proteínas Nucleares/fisiologia , Animais , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Proteínas de Transporte/biossíntese , Proteínas de Transporte/genética , Linhagem Celular Tumoral , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Regulação para Baixo , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Camundongos Nus , Proteínas Nucleares/biossíntese , Proteínas Nucleares/genética , Proteína 7 de Ligação ao Retinoblastoma , TransfecçãoRESUMO
BACKGROUND: The retinoblastoma (Rb) suppressor-associated protein 46 (RbAp46) is a member of the WD-repeat protein family and a component of histone modifying and remodeling complexes. Previously, we demonstrated that RbAp46 inhibits cell growth and suppresses the transformed phenotypes of tumor cell lines. MATERIALS AND METHODS: We established a tetracycline-inducible RbAp46 expression system in Saos-2 cells to test the effects of RbAp46 induction on cell growth in vitro and on tumor formation in vivo. RESULTS: We found that inducible expression of RbAp46 activated the c-Jun N-terminal kinase (JNK) signaling pathway and triggered apoptosis in Saos-2 cells. A dominant-negative mutant of JNK1, which can inhibit RbAp46-induced JNK activity, blocked RbAp46-mediated apoptosis. We also found that the induction of RbAp46 expression strongly suppressed the formation of tumors grafted in nude mice and drastically reduced growth of established tumor xenografts. CONCLUSION: These results revealed a novel proapoptotic activity for RbAp46 via the JNK pathway and demonstrated that induction of RbAp46 expression inhibits progressive growth of tumor grafts in vivo.