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1.
Cytotherapy ; 23(10): 874-885, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34116946

RESUMO

BACKGROUND AIMS: Cell-based regenerative medicine is an innovative field that can potentially alter the overall survival and quality of life of patients with devastating diseases. Several cell therapy products (CTPs) have been approved within the last two decades, and more are under development. The establishment of an effective developmental strategy in accordance with the regulatory bodies of each country/region is crucial for fast delivery of each respective CTP. In particular, facilitating investigational new drug (IND) approval is important for accelerating the transition from non-clinical to clinical research/trial phases. METHODS: Here the authors compared the non-clinical prerequisites for initiating clinical studies in five Asian countries/regions (India, China, Korea, Taiwan and Japan) from an industry viewpoint. The authors first identified the differences and tried to clarify the perspectives/considerations underpinning the different requirements. RESULTS: The authors' findings revealed that differences in regulations and development experiences, especially with CTPs, have led to clear differences in the non-clinical study package and its corresponding study design. CONCLUSIONS: By sharing experiences of the research and development of CTPs among Asian countries/regions and including not only industry but also regulatory authorities, we will be able to expedite cross-border IND approval and eventually contribute to the early delivery of innovative CTPs to many Asian patients.


Assuntos
Terapia Baseada em Transplante de Células e Tecidos , Qualidade de Vida , Ásia , China , Humanos , Japão
2.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(3): 640-7, 2016 Mar.
Artigo em Zh | MEDLINE | ID: mdl-27400497

RESUMO

To satisfy the demand of multilayer films on polarization detection, polarized bidirectional reflectance distribution function of multilayer films on slightly rough substrate is established on the basis of first-order vector perturbation theory and polarization transfer matrix. Due to the function, light scattering polarization properties are studied under multi-factor impacts of two typical targets-monolayer anti-reflection film and multilayer high-reflection films. The result shows that for monolayer anti-reflection film, observing positions have a great influence on the degree of polarization, for the left of the peak increased and right decreased compared with the substrate target. Film target and bare substrate can be distinguished by the degree of polarization in different observation angles. For multilayer high-reflection films, the degree of polarization is significantly associated with the number and optical thickness of layers at different wavelengths of incident light and scattering angles. With the increase of the layer number, the degree of polarization near the mirror reflection area decreases. It reveals that the calculated results coincide with the experimental data, which validates the correctness and rationality of the model. This paper provides a theoretical method for polarization detection of multilayer films target and reflection stealth technology.

3.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(3): 700-5, 2015 Mar.
Artigo em Zh | MEDLINE | ID: mdl-26117882

RESUMO

Study on polarized skylight spectral characters while observation geometry changing in different solar zenith angles (SZA), viewing zenith angles (VZA) or relative azimuth angles (RAA). Simulation calculation of cloudless daylight polarimetric spectrum is realized based on the solver, vector discrete ordinate method, of radiative transfer equation. In the Sun's principal and perpendicular plane, the spectral irradiance data, varying at wavelengths in the range between 0.4 and 3 µm, are calculated to extend the atmospheric polarization spectral information under the conditions: the MODTRAN solar reference spectrur is the only illuminant source; the main influencing factors of polarized radiative transfer include underlying surface albedo, aerosol layers and components, and the absorption of trace gases. Simulation analysis results: (1) While the relative azimuth angle is zero, the magnitude of spectrum U/I is lower than 10(-7) and V/I is negligible, the degree of polarization and the spectrum Q/I are shaped like the letter V or mirror-writing U. (2) In twilight, when the Sun is not in FOV of the detector, the polarization of the daytime sky has two maximum near 0.51 and 2.75 µm, and a minimum near 1.5 µm. For arbitrary observation geometry, the spectral signal of V/I may be ignored. According to observation geometry, choosing different spectral bands or polarized signal will be propitious to targets detection.

4.
J Proteome Res ; 12(8): 3573-85, 2013 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-23782096

RESUMO

Malignant tumors are relatively resistant to treatment due to their heterogeneous nature, drug resistance, and tendency for metastasis. Recent studies suggest that a subpopulation of cancer cells is responsible for the malignant outcomes. These cells are considered as cancer stem cells (CSC). Although a number of molecules have been identified in different cancer cells as markers for cancer stem cells, no promising markers are currently available for hepatocellular carcinoma cells. In this study, two clones of Hep3B cell lines were functionally characterized as control or CSC-like cells, based on properties including spheroid formation, drug resistance, and tumor initiation. Furthermore, their protein expression profiles were investigated by isobaric tags for relative and absolute quantitation (iTRAQ), and a total of 1,127 proteins were identified and quantified from the combined fractions; 50 proteins exhibited at least 2-fold differences between these two clones. These 50 proteins were analyzed by GeneGo and were found to be associated with liver neoplasms, hepatocellular carcinoma (HCC), and liver diseases. They were also components of metabolic pathways, immune responses, and cytoskeleton remodeling. Among these proteins, the expressions of S100P, S100A14, and vimentin were verified in several HCC cell lines, and their expressions were correlated with tumorigenicity in HCC cell lines. The functional significance of vimentin and S100A14 were also investigated and verified.


Assuntos
Biomarcadores Tumorais/genética , Carcinoma Hepatocelular/genética , Transformação Celular Neoplásica/genética , Neoplasias Hepáticas/genética , Células-Tronco Neoplásicas/metabolismo , Proteoma/genética , Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/patologia , Resistencia a Medicamentos Antineoplásicos/genética , Expressão Gênica , Perfilação da Expressão Gênica , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Espectrometria de Massas , Anotação de Sequência Molecular , Células-Tronco Neoplásicas/patologia , Proteoma/metabolismo , Proteínas S100/genética , Proteínas S100/metabolismo , Coloração e Rotulagem/métodos , Vimentina/genética , Vimentina/metabolismo
5.
Biochem Biophys Res Commun ; 439(3): 351-6, 2013 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-24012675

RESUMO

Receptor tyrosine kinases (RTKs) regulate many cellular processes, and Sprouty2 (Spry2) is known as an important regulator of RTK signaling pathways. Therefore, it is worth investigating the properties of Spry2 in more detail. In this study, we found that Spry2 is able to self-assemble into oligomers with a high-affinity KD value of approximately 16nM, as determined through BIAcore surface plasmon resonance analysis. The three-dimensional (3D) structure of Spry2 was resolved using an electron microscopy (EM) single-particle reconstruction approach, which revealed that Spry2 is donut-shaped with two lip-cover domains. Furthermore, the method of energy dispersive spectrum obtained through EM was analyzed to determine the elements carried by Spry2, and the results demonstrated that Spry2 is a silicon- and iron-containing protein. The silicon may contribute to the electroconductivity of Spry2, and this property exhibits a concentration-dependent feature. This study provides the first report of a silicon- and iron-containing protein, and its 3D structure may allow us (1) to study the potential mechanism through the signal transduction is controlled by switching the electronic transfer on or off and (2) to develop a new type of conductor or even semiconductor using biological or half-biological hybrid materials in the future.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular/química , Proteínas de Membrana/química , Animais , Condutividade Elétrica , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Ferro/análise , Proteínas de Membrana/metabolismo , Microscopia Eletrônica , Conformação Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Silício/análise
6.
Infect Drug Resist ; 16: 2611-2623, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37152403

RESUMO

Purpose: Hepatitis B virus-related acute-on-chronic liver failure (HBV-ACLF) is a serious medical condition with a high short-term mortality rate, making accurate prognostic assessment essential for informed clinical decision-making. In this study, we aimed to develop a simple and effective prognostic model for predicting short-term mortality in patients with HBV-ACLF. Patients and Methods: To achieve our objective, we enrolled both a cross-sectional cohort (n = 291) and a retrospective cohort (n = 185) in this study. We collected laboratory and clinical data from these cohorts and performed univariate and multivariate logistic regression analyses to identify independent predictors of short-term mortality. Subsequently, we developed a novel prognostic score for HBV-ACLF, which was validated and assessed using receiver operating characteristic (ROC) curve analysis to determine its performance. Results: Our analysis revealed that the admission prealbumin (PAB) level was a robust independent predictor of 30-day mortality, with an area under the receiver operating characteristic (AUROC) of 0.760. Moreover, we developed the HIAPP score, a prognostic-score model based on PAB. The HIAPP score was significantly lower in survivors compared to non-survivors (-2.80±0.21 vs 0.97±0.41, P < 0.001). The HIAPP score's AUROC value was 0.899, which was found to be superior to the MELD score (AUROC = 0.795) and the CLIF-C ACLF score (AUC =0.781) and comparable to the COSSH-ACLF II score (AUC =0.825) for predicting 30-day mortality. These findings were also validated in a separate cohort, further supporting the utility of the HIAPP score as a prognostic tool for HBV-ACLF patients. Conclusion: Our study identifies the admission PAB level as a simple and valuable predictive index for 30-day mortality in HBV-ACLF patients. Furthermore, the HIAPP score, which incorporates PAB, PLT, INR, HE, and age, is an easy-to-use and pragmatic prognostic score in predicting short-term mortality.

7.
J Infect Dev Ctries ; 16(8): 1336-1342, 2022 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-36099378

RESUMO

INTRODUCTION: The introduction of antiviral therapy in chronic hepatitis B (CHB) infection depends on precise evaluation of hepatic lesions. Total serum bile acids (TSBAs) are highly sensitive in monitoring liver dysfunction. We evaluated the predictive role of TSBAs for hepatic lesions in CHB patients with borderline alanine aminotransferase (ALT) and high level of hepatitis B virus (HBV) DNA copies. METHODOLOGY: 328 CHB patients were enrolled, 241 were hepatitis B e antigen (HBeAg)-positive and 87 were HBeAg-negative. Patients were further divided into two entities according to inflammation/fibrosis evaluated by liver biopsy, low-grade (inflammation grade < 2 and fibrosis stage < 2) and high-grade (inflammation grade ≥ 2 or/and fibrosis stage ≥ 2) cohorts. TSBAs were compared with noninvasive tools including aspartate aminnotransferase (AST)-to-platelet ratio index (APRI), fibrosis-4 (FIB-4) and red cell distribution width (RDW)-to-platelet ratio (RPR) to predict high-grade hepatic lesions in CHB subgroups. RESULTS: TSBAs, APRI, FIB-4 and RPR were statistically different between low- and high-grade patients in HBeAg-positive cohort. Only TSBAs showed significant difference between low and high grade in HBeAg-negative patients. Similarly, APRI, FIB-4 and RPR were correlated with different division of inflammation/fibrosis only in HBeAg-positive while TSBAs were correlated with inflammation/fibrosis levels in both HBeAg-positive and HBeAg-negative groups. Of the four indicators, the receiver operating characteristic (ROC) curve analysis showed that TSBAs have the maximum AUC (area under the curve) in HBeAg-negative group but the minimum in HBeAg-positive cohort. CONCLUSIONS: TSBAs can be used for predicting antiviral therapy in CHB patients with HBeAg-negative, borderline ALT and high HBV DNA.


Assuntos
Hepatite B Crônica , Hepatite B , Antivirais/uso terapêutico , Ácidos e Sais Biliares , DNA Viral , Fibrose , Antígenos E da Hepatite B , Hepatite B Crônica/tratamento farmacológico , Humanos , Inflamação , Cirrose Hepática/patologia
8.
Front Pharmacol ; 13: 943812, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36188594

RESUMO

Purpose: The "radiotherapy-pharmacokinetic" ("RT-PK") phenomenon refers to the fact that radiation can significantly alter the pharmacokinetic behavior of a drug. At present, it is not clear whether there is an "RT-PK" phenomenon that can affect apatinib during concurrent chemoradiotherapy. In this study, we used a rat irradiation model to study the effects of X-ray radiation on absorption, tissue distribution, and excretion of apatinib. Method: Healthy Sprague-Dawley (SD) rats were randomly divided into control and radiation groups. The radiation group was given an appropriate dose of abdominal X-ray radiation, while the control group was not given irradiation. After 24 h of recovery, both groups were given apatinib solution 45 mg/kg by gavage. A quantitative LC-MS/MS method was developed to determine the concentration of apatinib in the rats, so as to compare the differences between the control and radiation groups and thus investigate the modulating effect of radiation on the pharmacokinetics of apatinib in rats. Results: After abdominal X-ray irradiation, the area under the curve (AUC0-t) of apatinib in rat plasma decreased by 33.8% and 76.3% at 0.5 and 2 Gy, respectively. Clearance (CL) and volume of distribution (Vd) increased and were positively correlated with radiation dose. X-ray radiation significantly reduced the concentration of apatinib in the liver and small intestine, and there was no tissue accumulation. In excretion studies, we found that X-ray radiation reduced the cumulative excretion of apatinib in feces and urine by 11.24% and 86.17%, respectively. Conclusion: Abdominal X-ray radiation decreased plasma exposure, tissue distribution, and excretion of apatinib in rats, suggesting that the RT-PK phenomenon affects apatinib. We speculate that this RT-PK phenomenon is closely related to changes in metabolic enzymes in vivo. In clinical practice, when apatinib is combined with radiotherapy, attention should be paid to adjusting the dose of apatinib and optimizing the treatment plan to alleviate the adverse effects of this RT-PK phenomenon.

9.
Bioorg Med Chem Lett ; 20(20): 6129-32, 2010 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-20833039

RESUMO

A series of azulene-based derivatives were synthesized as potent inhibitors for receptor tyrosine kinases such as FMS-like tyrosine kinase 3 (FLT-3). Systematic side chain modification of prototype 1a was carried out through SAR studies. Analogue 22 was identified from this series and found to be one of the most potent FLT-3 inhibitors, with good pharmaceutical properties, superior efficacy, and tolerability in a tumor xenograft model.


Assuntos
Antineoplásicos/química , Antineoplásicos/uso terapêutico , Azulenos/química , Azulenos/uso terapêutico , Leucemia Mieloide Aguda/tratamento farmacológico , Receptores Proteína Tirosina Quinases/antagonistas & inibidores , Animais , Antineoplásicos/sangue , Antineoplásicos/farmacologia , Azulenos/sangue , Azulenos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Ratos , Receptores Proteína Tirosina Quinases/metabolismo , Tirosina Quinase 3 Semelhante a fms/antagonistas & inibidores
10.
Bioorg Med Chem ; 18(13): 4674-86, 2010 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-20570526

RESUMO

A series of new ureidoindolin-2-one derivatives were synthesized and evaluated as inhibitors of receptor tyrosine kinases. Investigation of structure-activity relationships at positions 5, 6, and 7 of the oxindole skeleton led to the identification of 6-ureido-substituted 3-pyrrolemethylidene-2-oxindole derivatives that potently inhibited both the vascular endothelial growth factor receptor (VEGFR) and platelet-derived growth factor receptor (PDGFR) families of receptor tyrosine kinases. Several derivatives showed potency against the PDGFR inhibiting both its enzymatic and cellular functions in the single-digit nanomolar range. Among them, compound 35 was a potent inhibitor against tyrosine kinases, including VEGFR and PDGFR families, as well as Aurora kinases. Inhibitor 36 (non-substituted on the pyrrole or phenyl ring) had a moderate pharmacokinetic profile and completely inhibited tumor growth initiated with the myeloid leukemia cell line, MV4-11, in a subcutaneous xenograft model in BALB/c nude mice.


Assuntos
Receptores ErbB/antagonistas & inibidores , Indóis/química , Inibidores de Proteínas Quinases/síntese química , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Pirróis/química , Receptores do Fator de Crescimento Derivado de Plaquetas/antagonistas & inibidores , Ureia/análogos & derivados , Animais , Aurora Quinases , Sítios de Ligação , Linhagem Celular Tumoral , Simulação por Computador , Ensaios de Seleção de Medicamentos Antitumorais , Receptores ErbB/metabolismo , Humanos , Indóis/uso terapêutico , Indóis/toxicidade , Leucemia Mieloide/tratamento farmacológico , Camundongos , Oxindóis , Inibidores de Proteínas Quinases/uso terapêutico , Inibidores de Proteínas Quinases/toxicidade , Proteínas Serina-Treonina Quinases/metabolismo , Pirróis/uso terapêutico , Pirróis/toxicidade , Receptores do Fator de Crescimento Derivado de Plaquetas/metabolismo , Relação Estrutura-Atividade , Transplante Heterólogo , Ureia/química , Ureia/uso terapêutico , Ureia/toxicidade
11.
Carcinogenesis ; 29(9): 1807-15, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18628248

RESUMO

Quercetin (QUE; 3,5,7,3',4'-tetrahydroxyflavone) has been shown to possess several beneficial biological activities including antitumor, anti-inflammation and antioxidant properties; however, the effects of QUE in preventing invasion by breast carcinoma cells are still undefined. Increases in the protein, messenger RNA and enzyme activity levels of matrix metalloproteinase (MMP)-9 were observed in 12-O-tetradecanoylphorbol-13-acetate (TPA)-treated MCF-7 cells, and these were blocked by QUE, but not by quercitrin or rutin. A translocation of protein kinase C (PKC)delta from the cytosol to the membrane followed by activation of extracellular signal-regulated kinase (ERK) and c-Jun/activator protein-1 (AP-1) by TPA was demonstrated, and TPA-induced MMP-9 activation and migration were inhibited by the pan PKC inhibitor, GF109203X, the specific PKCdelta inhibitor, rottlerin, an ERK inhibitor (PD98059) and an AP-1 inhibitor (curcumin). Application of QUE significantly suppressed TPA-induced activation of the PKCdelta/ERK/AP-1-signaling cascade. To elucidate the importance of hydroxyl (OH) substitutions to QUE's inhibition of tumor migration, several structurally related flavones of QUE including 3',4'-diOH, 3',4'-diOCH(3), 3,5,7-triOH, 3,4',4'-triOH, 3,3',4'-triOCH(3), luteolin and fisetin were used. Results suggested that OH groups at both C3' and C4' play central roles in QUE's inhibition of TPA-induced MMP-9 activation and migration, and an additional OH at C3, C5 or C7 may increase the inhibitory potency of the 3',4'-diOH flavone against TPA-induced MMP-9 activity and migration. The antitumor invasion and migration effects of breast carcinoma cells induced by QUE with the structure-activity relationship analysis were identified.


Assuntos
Neoplasias da Mama/enzimologia , Neoplasias da Mama/patologia , Ativação Enzimática/efeitos dos fármacos , Inibidores de Metaloproteinases de Matriz , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Proteína Quinase C-delta/metabolismo , Quercetina/análogos & derivados , Fator de Transcrição AP-1/metabolismo , Compostos de Bifenilo/farmacologia , Carcinógenos/farmacologia , Movimento Celular/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Hidrazinas/farmacologia , Radical Hidroxila/farmacologia , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , Invasividade Neoplásica , Picratos , Quercetina/uso terapêutico , Acetato de Tetradecanoilforbol/farmacologia , Transcrição Gênica/efeitos dos fármacos
12.
Oncogene ; 24(1): 101-6, 2005 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-15531925

RESUMO

Downstream signaling that results from the interaction of hepatocyte growth factor/scatter factor (HGF/SF) with the receptor tyrosine kinase Met plays critical roles in tumor development, progression, and metastasis. This ligand-receptor pair is an attractive target for new diagnostic and therapeutic agents, preclinical development of which requires suitable animal models. The growth of heterotopic and orthotopic Met-expressing human tumor xenografts in conventional strains of immunocompromised mice inadequately replicates the paracrine stimulation by human HGF/SF (hHGF/SF) that occurs in humans with cancer. We have therefore generated a mouse strain transgenic for hHGF/SF (designated hHGF-Tg) on a severe combined immunodeficiency (SCID) background. We report here that the presence of ectopically expressed hHGF/SF ligand significantly enhances growth of heterotopic subcutaneous xenografts derived from human Met-expressing cancer cells, including the lines SK-LMS-1 (human leiomyosarcoma), U118 (human glioblastoma), and DU145 (human prostate carcinoma), but not that of M14-Mel xenografts (human melanoma that expresses insignificant levels of Met). Our results indicate that ectopic hHGF/SF can specifically activate Met in human tumor xenografts. This new hHGF-Tg strain of mice should provide a powerful tool for evaluating drugs and diagnostic agents that target the various pathways influenced by Met activity.


Assuntos
Fator de Crescimento de Hepatócito/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Receptores de Fatores de Crescimento/metabolismo , Transplante Heterólogo , Animais , Fator de Crescimento de Hepatócito/genética , Humanos , Hospedeiro Imunocomprometido/imunologia , Camundongos , Camundongos SCID , Camundongos Transgênicos , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas c-met , Receptores de Fatores de Crescimento/genética , Fatores de Tempo , Células Tumorais Cultivadas
13.
Cancer Res ; 62(2): 589-96, 2002 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-11809714

RESUMO

Met tyrosine kinase, the receptor for HGF/SF, is important in various cellular functions, including proliferation, mitogenesis, formation of branching tubules, angiogenesis, and tumor cell invasion and metastasis. However, the role of Met/HGF signaling pathway in nasopharyngeal carcinoma (NPC) has not been evaluated. In this study, we determined the expression profile and clinical correlation of Met/HGF in 66 cases of advanced NPC and the activation mechanisms of Met receptor in five NPC cell lines. Immunofluorescent staining and quantitative image analysis showed that the Met protein was expressed throughout the tumors and normal nasopharyngeal epithelia. Compared with NPC, the Met expression level was higher in columnar nasopharyngeal epithelium but lower in squamous nasopharyngeal epithelium. The normal interstitial stromal tissue expressed the lowest level of Met protein. HGF was detected mainly in the normal interstitial tissue surrounding the tumor. Met protein expression level was inversely correlated with patients' survival time; the correlation coefficient was -0.319 (P = 0.009). The mean survival time was 118 months in low Met expression group versus 52 months in high expression group (P = 0.0004). The cumulative 5-year survival rate was 77.68% in low expression group versus 38.24% in high expression group. The clinical stage was also significantly more advanced in high Met expression group. In the multivariate analysis, both clinical stage and Met protein expression level were independent prognostic indicators for patient survival. All of the five NPC cell lines tested did not express hgf mRNA but expressed met mRNA, and tyrosine phosphorylation of Met protein was mainly induced by exogenous HGF stimulation in these cells. No mutation was found in the tyrosine kinase and the juxtamembrane domains of Met receptor in the five NPC cell lines tested. These results indicate that: (a) high Met protein expression level correlates with poorer survival in late-stage NPC and serves as an independent prognostic indicator; and (b) the Met receptor in NPC is activated by its paracrine ligand HGF from the interstitial tissues rather than by an autocrine loop or its activating mutation.


Assuntos
Neoplasias Nasofaríngeas/enzimologia , Proteínas Proto-Oncogênicas c-met/biossíntese , Adulto , Idoso , Biópsia , Feminino , Fator de Crescimento de Hepatócito/biossíntese , Fator de Crescimento de Hepatócito/genética , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/patologia , Prognóstico , Proteínas Proto-Oncogênicas c-met/genética , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Taxa de Sobrevida
14.
Oncogene ; 21(2): 217-26, 2002 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-11803465

RESUMO

Hepatocyte Growth Factor/Scatter Factor (HGF/SF) mediates a wide variety of cellular responses by acting through the Met tyrosine kinase receptor. Inappropriate expression of HGF/SF and/or Met has been found in most types of solid tumors and is often associated with poor prognosis. Importantly, constitutional and sporadic activating mutations in Met have been discovered in human papillary renal carcinomas and other cancers, while autocrine and paracrine signaling of this receptor/ligand pair has been shown to contribute to tumorigenesis and metastasis. Numerous downstream signaling molecules have been implicated in HGF/SF-Met mediated tumorigenesis and metastasis. Stat3 is a downstream signaling molecule activated by HGF/SF-Met signaling, and is reported to contribute to cell transformation induced by a diverse set of oncoproteins. Stat3 is constitutively activated in many primary tumors and tumor cell lines, suggesting that signaling by this molecule may be important for cell transformation. To address whether Stat3 is required for HGF/SF-Met mediated tumorigenesis and metastasis, we introduced a dominant-negative form of Stat3, Stat3beta into the human leiomyosarcoma cell line SK-LMS-1. We found that Stat3beta has no effect on the transformed morphology, proliferation, invasion or branching morphogenesis in vitro. By contrast, expression of Stat3beta affected HGF/SF-Met mediated anchorage-independent colony formation and prevented tumorigenic growth in athymic nu/nu mice. Thus, Met signaling through Stat3 provides an essential function for tumorigenic growth, which is manifested in vitro by loss of anchorage-independent growth.


Assuntos
Transformação Celular Neoplásica/efeitos dos fármacos , Proteínas de Ligação a DNA/metabolismo , Fator de Crescimento de Hepatócito/farmacologia , Transativadores/metabolismo , Proteínas de Fase Aguda/genética , Proteínas de Fase Aguda/metabolismo , Animais , Divisão Celular , Linhagem Celular , Proteínas de Ligação a DNA/genética , Morfogênese/fisiologia , Proteínas Recombinantes/metabolismo , Fator de Transcrição STAT3 , Transdução de Sinais , Transativadores/genética , Transfecção
15.
Oncogene ; 23(30): 5193-202, 2004 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-15122328

RESUMO

A strict regulation of hepatocyte growth factor/scatter factor (HGF/SF)-Met signaling is essential for its appropriate function. Several negative regulators of Met signaling have been identified. Here we report that human Spry2 is induced by HGF/SF and negatively regulates HGF/SF-Met signaling. We show that overexpression of Spry2 inhibits cell proliferation, anchorage-independent cell growth, and migration in wound-healing and in vitro invasion assays. Measured in an electric cell-substrate impedance sensing biosensor, cell movement is restricted, because Spry2 dramatically facilitates cell attachment and spreading by enhancing focal adhesions and increasing stress fibers. An analysis of cell cycle distribution shows, unexpectedly, that Spry2-GFP cells are polyploid. Thus, as with FGF and EGF receptors, Spry2-GFP tempers downstream Met signaling in addition to its pronounced effect on cell adhesion, and it has properties suitable to be considered a tumor-suppressor protein.


Assuntos
Divisão Celular , Movimento Celular , Regulação Neoplásica da Expressão Gênica , Fator de Crescimento de Hepatócito/metabolismo , Mitógenos/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Técnicas Biossensoriais , Western Blotting , Carcinoma de Células Renais/metabolismo , Carcinoma de Células Renais/patologia , Adesão Celular , Linhagem Celular Tumoral , Colágeno/metabolismo , Combinação de Medicamentos , Adesões Focais , Proteínas de Fluorescência Verde , Fator de Crescimento de Hepatócito/farmacologia , Humanos , Laminina/metabolismo , Leiomiossarcoma/metabolismo , Leiomiossarcoma/patologia , Proteínas Luminescentes/metabolismo , Mitógenos/farmacologia , Invasividade Neoplásica , Poliploidia , Proteoglicanas/metabolismo , Proteínas Proto-Oncogênicas c-met/metabolismo , Transdução de Sinais , Fibras de Estresse
16.
Oncogene ; 21(14): 2201-11, 2002 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-11948403

RESUMO

Hepatocyte growth factor (HGF) regulates various physiological and developmental processes in concert with other growth factors, cytokines and hormones. We examined interactions between cell signaling events elicited by HGF and the cytokine interleukin (IL)-4, in the IL-3-dependent murine myeloid cell line 32D transfected with the human HGF receptor, c-Met. HGF was a potent mitogen in these cells, and prevented apoptosis in response to IL-3 withdrawal. IL-4 showed modest anti-apoptotic activity, but no significant mitogenic activity. IL-4 synergistically enhanced HGF-stimulated DNA synthesis, whereas only additive prevention of apoptosis was observed. IL-4 did not enhance HGF-dependent tyrosine phosphorylation of c-Met or Shc. In contrast, HGF-stimulated activation of MAP kinases was enhanced by IL-4, suggesting that the IL-4 and HGF signaling pathways converge upstream of these events. Although phosphatidylinositol 3-kinase (PI3K) inhibitors diminished HGF-induced mitogenesis, anti-apoptosis, and MAP kinase activation, IL-4 enhanced HGF signaling persisted even in the presence of these inhibitors. IL-4 enhancement of HGF signaling was partially blocked in 32D/c-Met cells treated with inhibitors of MEK1 or c-Src kinases, completely blocked by expression of a catalytically inactive mutant of Janus kinase 3 (Jak3), and increased in 32D/c-Met cells overexpressing STAT6. Our results suggest that the IL-4 and HGF pathways converge at multiple levels, and that IL-4-dependent Jak3 and STAT6 activities modulate signaling events independent of PI3K to enhance HGF-dependent mitogenesis in myeloid cells, and possibly other common cellular targets.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Proteínas Adaptadoras de Transporte Vesicular , Fator de Crescimento de Hepatócito/farmacologia , Interleucina-4/farmacologia , Mitógenos/farmacologia , Transdução de Sinais/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Hepatócitos/citologia , Hepatócitos/efeitos dos fármacos , Interleucina-3/farmacologia , Interleucina-4/antagonistas & inibidores , Janus Quinase 3 , MAP Quinase Quinase 1 , Camundongos , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Tirosina Quinases/metabolismo , Proteínas/antagonistas & inibidores , Proteínas/metabolismo , Proteínas Proto-Oncogênicas c-met/metabolismo , Fator de Transcrição STAT6 , Proteínas Adaptadoras da Sinalização Shc , Proteína 1 de Transformação que Contém Domínio 2 de Homologia de Src , Fatores de Tempo , Transativadores/metabolismo , Transfecção , Células Tumorais Cultivadas
17.
Clin Cancer Res ; 9(10 Pt 2): 3839S-44S, 2003 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-14506181

RESUMO

PURPOSE: Inappropriate expression of the receptor tyrosine kinase Met and its ligand is associated with an aggressive phenotype and poor clinical prognosis for a wide variety of solid human tumors. We are developing imaging and therapeutic agents that target this receptor-ligand complex. In this study, we evaluated the ability of radioiodinated anti-Met monoclonal antibodies from a single hybridoma clone to image human Met-expressing tumor xenografts. EXPERIMENTAL DESIGN: Xenografts of four different tissue origins were raised s.c. in host athymic nude mice. Animals received i.v. injections of I-125-Met3, posterior total body gamma camera images were acquired for several days after injection, and quantitative region-of-interest activity analysis was performed. RESULTS: The autocrine Met-expressing tumors S-114 and SK-LMS-1/HGF and the paracrine Met-expressing human prostate carcinoma PC-3 were satisfactorily imaged with I-125-Met3. By region-of-interest analysis, mean initial tumor-associated activities in S-114, SK-LMS-1/HGF, and PC-3 were 18.6 +/- 2.1, 7.2 +/- 2.2, and 5.4 +/- 2.6% estimated injected activity, and the mean ratios of tumor:total body activity at 3 days after injection were 0.32 +/- 0.13, 0.15 +/- 0.06, and 0.10 +/- 0.04, respectively. Human melanoma xenografts, however, accounted for < or =3% of injected or total body activity. We observed a direct rank order correlation between relative levels of Met3-derived radioactivity in xenografts and relative quantities of Met expressed by the respective cultured tumor cell lines. CONCLUSIONS: We conclude that I-125-Met3 is effective for imaging human Met-expressing xenografts of different tissue origins, and we infer that I-125-Met3 distinguishes human tumor xenografts according to their levels of Met expression.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Radioimunodetecção/métodos , Animais , Anticorpos Monoclonais/química , Linhagem Celular Tumoral , Separação Celular , Citometria de Fluxo , Humanos , Hibridomas , Imuno-Histoquímica , Ligantes , Camundongos , Camundongos Nus , Transplante de Neoplasias , Fenótipo , Ligação Proteica , Proteínas Proto-Oncogênicas c-met/química , Fatores de Tempo
18.
Int J Clin Exp Pathol ; 7(9): 6395-8, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25337298

RESUMO

Mixed adenoneuroendocrine carcinoma (MANEC) is exceedingly rare with a poor outcome. In this article, we reported a MANEC in a 68-year-old woman with a symptom of abdominal pain and distension. MANEC derived from the ascending colon with highly aggressive behavior. The diagnosis and distinguish of MANEC must base on histological findings and immunohistochemical findings. In this case, microscopic observation showed tumor cells were arranged in conglobate and nested by fibrous tissue with a visible cell atypia and mitotic. NEC-like and exocrine glandular cells were also been seen in a single neoplasm. MANEC tissues were immunopositive for CK, CK20, P53, CK7, CDX-2, Ki-67 (70%+), E-cad, CD56, CEA, Syn, villin and CgA, and immunonegative for CA125, NSE, ER and PR. Here, the patient was treated by surgical operation and was followed-up near 3 months, no local recurrence and distant metastasis.


Assuntos
Adenocarcinoma/patologia , Carcinoma Neuroendócrino/patologia , Neoplasias do Colo/patologia , Mucosa Intestinal/patologia , Neoplasias Complexas Mistas/patologia , Adenocarcinoma/química , Adenocarcinoma/cirurgia , Idoso , Biomarcadores Tumorais/análise , Biópsia , Carcinoma Neuroendócrino/química , Carcinoma Neuroendócrino/cirurgia , Colectomia , Neoplasias do Colo/química , Neoplasias do Colo/cirurgia , Feminino , Humanos , Imuno-Histoquímica , Mucosa Intestinal/química , Invasividade Neoplásica , Neoplasias Complexas Mistas/química , Neoplasias Complexas Mistas/cirurgia , Resultado do Tratamento
19.
Int J Clin Exp Pathol ; 7(5): 2654-7, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24966981

RESUMO

In this article, we described a malignant myoepithelioma of the breast (MMB) in a 69-year-old woman. Breast cancer derived from myoepithelial cells is very rare, usually benign. The diagnosis of MMB based on histological and immunohistochemical finding. In this case, the author diagnosed the tumor as MMB, because tumor tissues were immunopositive for 34ßE12, P63, SMA, S-100, CD10, E-Cad and Ki-67, and immunnegative for CK5/6, desmin, ER, PR and C-erbB-2, because tumor tissue showed invasive growth and local hemorrhage or necrosis, suggesting malignant, and also because there was a transition between the tumor cells and hyperplastic myoepithelium of non-tumorous ducts. The patient's postoperative recovery is smooth and regular following of patient is essential.


Assuntos
Neoplasias da Mama/patologia , Mioepitelioma/patologia , Idoso , Biomarcadores Tumorais/análise , Biópsia , Neoplasias da Mama/química , Neoplasias da Mama/cirurgia , Proliferação de Células , Feminino , Humanos , Hiperplasia , Imuno-Histoquímica , Mastectomia Radical , Mioepitelioma/química , Mioepitelioma/cirurgia , Necrose , Invasividade Neoplásica
20.
Int J Clin Exp Pathol ; 7(1): 456-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24427372

RESUMO

In this article, we described an ovarian sclerosing stromal tumor (SST) in a young woman with ectopic pregnancy. It is important to distinguish SST from fibroma, thecoma, and lipoid cell tumors clinically and histologically. Several unique histologic features including pseudolobulation, sclerosis and prominent vascularity are clearly reflected at histopathological findings. The SST cells were immunopositive for CD34, Desmin and SMA, and negative for factor VIII-related antigen, CD31, S-100, ER and PR. The patient's postoperative recovery was smooth and she was discharged after 21 days.


Assuntos
Neoplasias Ovarianas/patologia , Complicações Neoplásicas na Gravidez/patologia , Gravidez Tubária , Tumores do Estroma Gonadal e dos Cordões Sexuais/patologia , Adulto , Feminino , Humanos , Gravidez
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