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2.
Sci Rep ; 8(1): 15536, 2018 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-30341310

RESUMO

We developed hybrid slot antenna structures for microbial sensing in the THz frequency range, where silver nanowires (AgNWs) were employed to increase the sensitivity. In order to fabricate the hybrid devices, we partially etched the AgNW in the slot antenna region, where we can expect the field enhancement effect at the AgNW tip. We measured the resonant-frequency shift observed upon the deposition of a polymer layer, and observed that the sensitivity increased upon the introduction of AgNWs, with an enhancement factor of more than four times (approximately six times in terms of figure-of-merit). The sensitivity increased with the AgNW density until saturation. In addition, we tested devices with PRD1 viruses, and obtained an enhancement factor of 3.4 for a slot antenna width of 3 µm. Furthermore, we performed finite-difference time-domain simulations, which confirmed the experimental results. The sensitivity enhancement factor decreased with the decrease of the slot width, consistent with the experimental findings. Two-dimensional mapping of the electric field confirmed the strong field localization and enhancement at the AgNW tips.

3.
Lupus ; 27(11): 1854-1859, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30139297

RESUMO

Mesenchymal stem cell therapy is a promising candidate for the treatment of systemic lupus erythematosus (SLE). To exert their efficacy fully, mesenchymal stem cells must infiltrate efficiently into the lesion sites. Here, we examined the role of CXCR3 in mesenchymal stem cell infiltration into the kidney of MRL. Faslpr mice, which highly expressed CXCL10. The phenotypes, production of immunosuppressive mediators, and capacity to inhibit T and B cells of CXCR3-deficient mesenchymal stem cells were similar to those of wild-type mesenchymal stem cells. However, they showed less infiltration into the nephritic kidney, less conjugation with endothelial cells and weaker MMP-9 expression than did wild-type mesenchymal stem cells. Consequently, CXCR3-deficient mesenchymal stem cells did not ameliorate lupus symptoms in MRL. Faslpr mice in comparison with wild-type mesenchymal stem cells. In summary, our data suggest that upregulation of CXCR3 in mesenchymal stem cells will be a good strategy to increase their infiltration into the kidney, which will improve therapeutic outcomes in SLE.


Assuntos
Rim/patologia , Lúpus Eritematoso Sistêmico/terapia , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Animais , Linfócitos B/metabolismo , Expressão Gênica , Imunoglobulina G/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos MRL lpr , Receptores CXCR3/deficiência , Receptores CXCR3/genética
4.
Sci Rep ; 7(1): 3824, 2017 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-28630451

RESUMO

The band alignment at an Al2O3/SrTiO3 heterointerface forming a two-dimensional electron gas (2DEG) was investigated using scanning photocurrent microscopy (SPCM) in an electrolyte-gated environment. We used a focused UV laser source for above-the-bandgap illumination on the SrTiO3 layer, creating electron-hole pairs that contributed to the photocurrent through migration towards the metal electrodes. The polarity of the SPCM signals of a bare SrTiO3 device shows typical p-type behavior at zero gate bias, in which the photogenerated electrons are collected by the electrodes. In contrast, the SPCM polarity of 2DEG device indicates that the hole carriers were collected by the metal electrodes. Careful transport measurements revealed that the gate-dependent conductance of the 2DEG devices exhibits n-type switching behavior. More importantly, the SPCM signals in 2DEG devices demonstrated very unique gate-responses that cannot be found in conventional semiconducting devices, based on which we were able to perform detailed investigation into the electronic band alignment of the 2DEG devices and obtain the valence band offset at the heterointerface.

5.
J Phys Chem Lett ; 8(2): 401-406, 2017 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-28050908

RESUMO

Vibrational modes in the terahertz (THz) frequency range are good indicators of lead halide perovskite's crystallization phase. We performed real-time THz spectroscopy to monitor the crystallization kinetics in the perovskite films. First, THz absorptance was measured while the perovskite film was annealed at different temperatures. By analyzing the Avrami exponent, we observed an abrupt dimensionality switch (from 1D to 2D) with increasing temperature starting at approximately 90 °C. We also monitored the laser-induced crystallinity enhancement of the preannealed perovskite film. The THz absorptance increased initially, then subsequently decayed over a couple of hours, although the enhancement factor varies depending on the film crystallinity. In particular, the Avrami analysis implied that the light-induced crystallization was assisted by the 1D diffusion processes. The activation photon energy was measured at 2.3 eV, which indicated that enhanced crystallization originated from the photoinduced structural change of residual lead iodide at the grain boundary.

6.
Cell Death Dis ; 7: e2208, 2016 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-27124582

RESUMO

Concanavalin A (Con A)-induced hepatitis model is well-established experimental T cell-mediated liver disease. Reactive oxygen species (ROS) is associated with T-cell activation and proliferation, but continued ROS exposure induces T-cell hyporesponsiveness. Because glutathione peroxidase 1 (Gpx1) is an antioxidant enzyme and is involved in T-cell development, we investigated the role of Gpx1 during Con A-induced liver injury in Gpx1 knockout (KO) mice. Male wild-type (WT) mice and Gpx1 KO mice were intravenously injected with Con A (10 mg/kg), and then killed after 8 h after Con A injection. Serum levels of aspartate transaminase and alanine transaminase were measured to assess hepatic injury. To identify that Gpx1 affects T cell-mediated inflammation, we pretreated Gpx1 inhibitor to Human Jurkat T cells then treated Con A. Con A-induced massive liver damage in WT mice but its damage was attenuated in Gpx1 KO mice. Con A-induced Th1 cytokines such as tumor necrosis factor-α (TNF-α), interferon-γ (IFN-γ) and interleukin (IL)-2 were also decreased in the liver and spleen of Gpx1 KO mice compared with WT mice. In Jurkat T cells, Con A-induced mRNA levels of IL-2, IFN-γ and TNF-α were downregulated by pretreatment of Gpx inhibitor, mercaptosuccinic acid. We also observed that Gpx1 KO mice showed increasing oxidative stress in the liver and spleen compared with WT mice. These results suggest that Gpx1 deficiency attenuates Con A-induced liver injury by induction of T-cell hyporesponsiveness through chronic ROS exposure.


Assuntos
Concanavalina A/toxicidade , Glutationa Peroxidase/metabolismo , Ativação Linfocitária/efeitos dos fármacos , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Regulação para Baixo/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Glutationa Peroxidase/antagonistas & inibidores , Glutationa Peroxidase/genética , Humanos , Interferon gama/genética , Interferon gama/metabolismo , Interleucina-2/genética , Interleucina-2/metabolismo , Células Jurkat , Fígado/lesões , Fígado/metabolismo , Fígado/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Estresse Oxidativo/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Baço/metabolismo , Linfócitos T/citologia , Linfócitos T/metabolismo , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo , Glutationa Peroxidase GPX1
7.
Cell Death Dis ; 6: e1819, 2015 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-26181200

RESUMO

Dalbergia odorifera has been traditionally used as a medicine to treat many diseases. However, the role of 2,4,5-trimethoxyldalbergiquinol (TMDQ) isolated and extracted from D. odorifera in osteoblast function and the underlying molecular mechanisms remain poorly understood. The aim of this study was to investigate the effects and possible underlying mechanisms of TMDQ on osteoblastic differentiation of primary cultures of mouse osteoblasts as an in vitro assay system. TMDQ stimulated osteoblastic differentiation, as assessed by the alkaline phosphatase (ALP) activity, ALP staining, mineralized nodule formation, and the levels of mRNAs encoding the bone differentiation markers, including ALP, bone sialoprotein (BSP), osteopontin, and osteocalcin. TMDQ upregulated the expression of Bmp2 and Bmp4 genes, and increased the protein level of phospho-Smad1/5/8. Furthermore, TMDQ treatment showed the increased mRNA expression of Wnt ligands, phosphorylation of GSK3, and the expression of ß-catenin protein. The TMDQ-induced osteogenic effects were abolished by Wnt inhibitor, Dickkopf-1 (DKK1), and bone morphogenetic protein (BMP) antagonist, noggin. TMDQ-induced runt-related transcription factor 2 (Runx2) expression was attenuatted by noggin and DKK1. These data suggest that TMDQ acts through the activation of BMP, Wnt/ß-catenin, and Runx2 signaling to promote osteoblast differentiation, and we demonstrate that TMDQ could be a potential agent for the treatment of bone loss-associated diseases such as osteoporosis.


Assuntos
Anisóis/administração & dosagem , Compostos Benzidrílicos/administração & dosagem , Diferenciação Celular/genética , Dalbergia/química , Osteoblastos/efeitos dos fármacos , Extratos Vegetais/administração & dosagem , Fosfatase Alcalina/biossíntese , Animais , Proteínas de Transporte/biossíntese , Proteínas de Transporte/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Sialoproteína de Ligação à Integrina/biossíntese , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Camundongos , Osteoblastos/metabolismo , Osteocalcina/biossíntese , Osteopontina/biossíntese , Osteoporose/genética , Osteoporose/patologia , Extratos Vegetais/química , RNA Mensageiro/biossíntese , Via de Sinalização Wnt/efeitos dos fármacos
8.
Clin Radiol ; 70(8): 835-43, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25979852

RESUMO

AIM: To retrospectively analyse the synchondrosis from the occipital bone to the whole cervical spine and determine the feasibility and validity of age estimation using computed tomography (CT) images. MATERIAL AND METHODS: A total of 231 cervical spine or neck CT images of young children (<7 years of age) were examined. Twelve ossification centres were assessed (occiput: n = 2; atlas: n = 2; axis, n = 6; whole sub-axial vertebra: n = 2), and the ossification process was graded as open (O, fully lucent), osseous bridging (B, partially ossified), and fusion (F, totally ossified). After the first analysis was completed, the resulting chronological chart was used to estimate the age of 10 new cases in order to confirm the usefulness of the chart. RESULTS: Infancy was easily estimated using the sub-axial or C2 posterior ossification centres, while the posterior occipital regions provided good estimation of age between 1-2 years. The most difficult period for accurate age estimation was between 2-4 years. However, the C2 anterior (neurocentral ossification) and C1 posterior regions did yield information to help determine the age around 3 years. The anterior occipital region was useful for age estimation between 4-5 years, and the C1-anterior region was potentially useful to help decide among the other parameters. The test for age estimation (TAE) had a very high ICC score (0.973) among the three observers. CONCLUSION: Segmentalised analysis can enhance the ability to estimate real age, at least by the year. The analysis of the occipital bone made a strong contribution to the usefulness of the chorological chart. An organised chronological chart can provide readily available information for age estimation, and the primary application of the above data (TAE) demonstrated the validity of this approach.


Assuntos
Envelhecimento/fisiologia , Vértebras Cervicais/diagnóstico por imagem , Osso Occipital/diagnóstico por imagem , Osteogênese/fisiologia , Pediatria/métodos , Tomografia Computadorizada por Raios X/métodos , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Reprodutibilidade dos Testes , Estudos Retrospectivos
9.
Sci Rep ; 4: 4988, 2014 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-24832607

RESUMO

Microorganisms such as fungi and bacteria cause many human diseases and therefore rapid and accurate identification of these substances is essential for effective treatment and prevention of further infections. In particular, contemporary microbial detection technique is limited by the low detection speed which usually extends over a couple of days. Here we demonstrate that metamaterials operating in the terahertz frequency range shows promising potential for use in fabricating the highly sensitive and selective microbial sensors that are capable of high-speed on-site detection of microorganisms in both ambient and aqueous environments. We were able to detect extremely small amounts of the microorganisms, because their sizes are on the same scale as the micro-gaps of the terahertz metamaterials. The resonant frequency shift of the metamaterials was investigated in terms of the number density and the dielectric constants of the microorganisms, which was successfully interpreted by the change in the effective dielectric constant of a gap area.


Assuntos
Bactérias/química , Fungos/química , Ressonância de Plasmônio de Superfície/métodos , Espectroscopia Terahertz/métodos , Radiação Terahertz
10.
Oncogene ; 33(44): 5193-200, 2014 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-24858037

RESUMO

Presenilins are the enzymatic components of γ-secretase complex that cleaves amyloid precursor protein, Notch and ß-catenin, which has critical roles in the development of Alzheimer's disease and cancer cell growth. Therefore, in the present study, we studied the effects and mechanisms of PS2 knockout on lung cancer development and possible mechanisms as a key regulator of lung tumor development. We compared carcinogen-induced tumor growth between PS2 knockout mice and wild-type mice. PS2 knockout mice showed increased urethane (1 mg/g)-induced lung tumor incidence when compared with that of wild-type mice with decreased activity of γ-secretase in the lung tumor tissues. Consequently, iPLA2 activities in lung tumor tissues of PS2 knockout mice were much higher than in tumor tissues of wild-type mice. Furthermore, knockdown of PS2 using PS2 siRNA decreased γ-secretase activity with increased iPLA2 activity in the lung cancer cells (A549 and NCI-H460), leading to increased lung cancer cell growth. PS2 knockout mice and PS2 knockdown lung cancer cells showed increased DNA-binding activities of nuclear factor kappa-beta, signal transducer and activator of transcription 3 (STAT3) and AP-1 which are critical transcriptional factors of iPLA2 than those of PS2 wild-type mice and control lung cancer cells. Taken together, these results suggest that the loss of PS2 could have a critical role in lung tumor development through the upregulation of iPLA2 activity by reducing γ-secretase.


Assuntos
Fosfolipases A2 do Grupo VI/metabolismo , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Presenilina-2/genética , Animais , Linhagem Celular Tumoral , Fosfolipases A2 do Grupo VI/genética , Humanos , Neoplasias Pulmonares/genética , Camundongos Endogâmicos C57BL , Camundongos Knockout , NF-kappa B/metabolismo , Peroxirredoxina VI/genética , Peroxirredoxina VI/metabolismo , Presenilina-2/metabolismo , Fator de Transcrição STAT3/metabolismo , Fator de Transcrição AP-1/metabolismo
11.
Cell Death Dis ; 4: e958, 2013 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-24336078

RESUMO

Mesenchymal stem cells (MSCs) promote functional recoveries in pathological experimental models of central nervous system (CNS) and are currently being tested in clinical trials for neurological disorders, but preventive mechanisms of placenta-derived MSCs (PD-MSCs) for Alzheimer's disease are poorly understood. Herein, we investigated the inhibitory effect of PD-MSCs on neuronal cell death and memory impairment in Aß1-42-infused mice. After intracerebroventrical (ICV) infusion of Aß1-42 for 14 days, the cognitive function was assessed by the Morris water maze test and passive avoidance test. Our results showed that the transplantation of PD-MSCs into Aß1-42-infused mice significantly improved cognitive impairment, and behavioral changes attenuated the expression of APP, BACE1, and Aß, as well as the activity of ß-secretase and γ-secretase. In addition, the activation of glia cells and the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) were inhibited by the transplantation of PD-MSCs. Furthermore, we also found that PD-MSCs downregulated the release of inflammatory cytokines as well as prevented neuronal cell death and promoted neuronal cell differentiation from neuronal progenitor cells in Aß1-42-infused mice. These data indicate that PD-MSC mediates neuroprotection by regulating neuronal death, neurogenesis, glia cell activation in hippocampus, and altering cytokine expression, suggesting a close link between the therapeutic effects of MSCs and the damaged CNS in Alzheimer's disease.


Assuntos
Doença de Alzheimer/terapia , Peptídeos beta-Amiloides/metabolismo , Transtornos da Memória/terapia , Placenta/citologia , Doença de Alzheimer/etiologia , Doença de Alzheimer/metabolismo , Doença de Alzheimer/fisiopatologia , Peptídeos beta-Amiloides/genética , Animais , Western Blotting , Feminino , Humanos , Imuno-Histoquímica , Masculino , Transtornos da Memória/etiologia , Transtornos da Memória/fisiopatologia , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/fisiologia , Camundongos , Camundongos Endogâmicos ICR , Gravidez
12.
Cell Death Dis ; 4: e640, 2013 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-23703385

RESUMO

Cytokine and activation of lymphocytes are critical for tumor growth. We investigated whether interleukin (IL)-32ß overexpression changes other cytokine levels and activates cytotoxic lymphocyte, and thus modify tumor growth. Herein, IL-32ß inhibited B16 melanoma growth in IL-32ß-overexpressing transgenic mice (IL-32ß mice), and downregulated the expressions of anti-apoptotic proteins (bcl-2, IAP, and XIAP) and cell growth regulatory proteins (Ki-67 antigen (Ki-67) and proliferating cell nuclear antigen (PCNA)), but upregulated the expressions of pro-apoptotic proteins (bax, cleaved caspase-3, and cleaved caspase-9). IL-32ß also inhibited colon and prostate tumor growth in athymic nude mice inoculated with IL-32ß-transfected SW620 colon or PC3 prostate cancer cells. The forced expression of IL-32ß also inhibited cell growth in cultured colon and prostate cancer cells, and these inhibitory effects were abolished by IL-32 small interfering RNA (siRNA). IL-10 levels were elevated, but IL-1ß, IL-6, and tumor necrosis factor-alpha (TNF-α) levels were reduced in the tumor tissues and spleens of IL-32ß mice, and athymic nude mice. The number of cytotoxic T (CD8(+)) and natural killer (NK) cells in tumor tissues, spleen, and blood was significantly elevated in IL-32ß mice and athymic nude mice inoculated with IL-32ß-transfected cancer cells. Constituted activated NF-κB and STAT3 levels were reduced in the tumor tissues of IL-32ß mice and athymic nude mice, as well as in IL-32ß-transfected cultured cancer cells. These findings suggest that IL-32ß inhibits tumor growth by increasing cytotoxic lymphocyte numbers, and by inactivating the NF-κB and STAT3 pathways through changing of cytokine levels in tumor tissues.


Assuntos
Interleucinas/metabolismo , NF-kappa B/metabolismo , Fator de Transcrição STAT3/metabolismo , Animais , Proteínas Reguladoras de Apoptose/metabolismo , Caspase 3/metabolismo , Caspase 9/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Citocinas/metabolismo , Feminino , Células HCT116 , Humanos , Interleucinas/antagonistas & inibidores , Interleucinas/genética , Antígeno Ki-67/metabolismo , Células Matadoras Naturais/citologia , Células Matadoras Naturais/imunologia , Ativação Linfocitária , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Nus , Camundongos Transgênicos , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Transdução de Sinais , Linfócitos T Citotóxicos/citologia , Linfócitos T Citotóxicos/imunologia , Transplante Heterólogo , Proteína X Associada a bcl-2/metabolismo
13.
Opt Express ; 21(6): 7633-40, 2013 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-23546146

RESUMO

We performed time-domain terahertz (THz) spectroscopy on reduced graphene oxide (rGO) network films coated on quartz substrates from dispersion solutions by spraying method. The rGO network films demonstrate high conductivity of about 900 S/cm in the THz frequency range after a high temperature reduction process. The frequency-dependent conductivities and the refractive indexes of the rGO films have been obtained and analyzed with respect to the Drude free-electron model, which is characterized by large scattering rate. Finally, we demonstrate that the THz conductivities can be manipulated by controlling the reduction process, which correlates well with the DC conductivity above the percolation limit.


Assuntos
Grafite/química , Óxidos/química , Radiação Terahertz , Condutividade Elétrica , Teste de Materiais
14.
Br J Pharmacol ; 168(5): 1133-45, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23043610

RESUMO

BACKGROUND AND PURPOSE: The effects of 4-O-methylhonokiol (MH), a constituent of Magnolia officinalis, were investigated on human prostate cancer cells and its mechanism of action elucidated. EXPERIMENTAL APPROACH: The anti-cancer effects of MH were examined in prostate cancer and normal cells. The effects were validated in vivo using a mouse xenograft model. KEY RESULTS: MH increased the expression of PPARγ in prostate PC-3 and LNCap cells. The pull-down assay and molecular docking study indicated that MH directly binds to PPARγ. MH also increased transcriptional activity of PPARγ but decreased NF-κB activity. MH inhibited the growth of human prostate cancer cells, an effect attenuated by the PPARγ antagonist GW9662. MH induced apoptotic cell death and this was related to G(0) -G(1) phase cell cycle arrest. MH increased the expression of the cell cycle regulator p21, and apoptotic proteins, whereas it decreased phosphorylation of Rb and anti-apoptotic proteins. Transfection of PC3 cells with p21 siRNA or a p21 mutant plasmid on the cyclin D1/ cycline-dependent kinase 4 binding site abolished the effects of MH on cell growth, cell viability and related protein expression. In the animal studies, MH inhibited tumour growth, NF-κB activity and expression of anti-apoptotic proteins, whereas it increased the transcriptional activity and expression of PPARγ, and the expression of apoptotic proteins and p21 in tumour tissues. CONCLUSIONS AND IMPLICATION: MH inhibits growth of human prostate cancer cells through activation of PPARγ, suppression of NF-κB and arrest of the cell cycle. Thus, MH might be a useful tool for treatment of prostate cancer.


Assuntos
Antineoplásicos/farmacologia , Compostos de Bifenilo/farmacologia , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Lignanas/farmacologia , NF-kappa B/metabolismo , PPAR gama/agonistas , Neoplasias da Próstata/tratamento farmacológico , Animais , Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Compostos de Bifenilo/uso terapêutico , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Lignanas/uso terapêutico , Masculino , Camundongos , Camundongos Nus , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
15.
Br J Cancer ; 107(1): 53-62, 2012 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-22677907

RESUMO

BACKGROUND: Although the proteasome is a validated anticancer target, the clinical application of its inhibitors has been limited because of inherent systemic toxicity. To broaden clinical utility of proteasome inhibitors as anticancer agents, it is critical to develop strategies to selectively target proteasomes in cancer cells. The immunoproteasome is an alternative form of the constitutive proteasome that is expressed at high levels in cancer tissues, but not in most normal cells in the body. METHODS: To validate the immunoproteasome as a chemotherapeutic target, an immunoproteasome catalytic subunit LMP2-targeting inhibitor and siRNA were used. The sensitivity of PC-3 prostate cancer cells to these reagents was investigated using viability assays. Further, a xenograft model of prostate cancer was studied to test the in vivo effects of LMP2 inhibition. RESULTS: A small molecule inhibitor of the immunoproteasome subunit LMP2, UK-101, induced apoptosis of PC-3 cells and resulted in significant inhibition (~50-60%) of tumour growth in vivo. Interestingly, UK-101 did not block degradation of IκBα in PC-3 cells treated with TNF-α, suggesting that its mode of action may be different from that of general proteasome inhibitors, such as bortezomib, which block IκBα degradation. CONCLUSION: These results strongly suggest that the immunoproteasome has important roles in cancer cell growth and thus provide a rationale for targeting the immunoproteasome in the treatment of prostate cancer.


Assuntos
Cisteína Endopeptidases/genética , Neoplasias da Próstata/genética , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Cisteína Endopeptidases/efeitos dos fármacos , Dipeptídeos/farmacologia , Humanos , Masculino , Camundongos , Camundongos Nus , Transplante de Neoplasias , Compostos de Organossilício/farmacologia , RNA Interferente Pequeno/farmacologia , Transplante Heterólogo
16.
Cell Prolif ; 44(4): 320-9, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21645154

RESUMO

OBJECTIVES: Melanoma is the most aggressive form of skin cancer, and it resists chemotherapy. Candidate drugs for effective anti-cancer treatment have been sought from natural resources. Here, we have investigated anti-proliferative activity of myriocin, serine palmitoyltransferase inhibitor, in the de novo sphingolipid pathway, and its mechanism in B16F10 melanoma cells. MATERIAL AND METHODS: We assessed cell population growth by measuring cell numbers, DNA synthesis, cell cycle progression, and expression of cell cycle regulatory proteins. Ceramide, sphingomyelin, sphingosine and sphingosine-1-phosphate levels were analysed by HPLC. RESULTS: Myriocin inhibited proliferation of melanoma cells and induced cell cycle arrest in the G(2) /M phase. Expressions of cdc25C, cyclin B1 and cdc2 were decreased in the cells after exposure to myriocin, while expression of p53 and p21(waf1/cip1) was increased. Levels of ceramide, sphingomyelin, sphingosine and sphingosine-1-phosphate in myriocin-treated cells after 24 h were reduced by approximately 86%, 57%, 75% and 38%, respectively, compared to levels in control cells. CONCLUSIONS: Our results suggest that inhibition of sphingolipid synthesis by myriocin in melanoma cells may inhibit expression of cdc25C or activate expression of p53 and p21(waf1/cip1) , followed by inhibition of cyclin B1 and cdc2, resulting in G(2) /M arrest of the cell cycle and cell population growth inhibition. Thus, modulation of sphingolipid metabolism by myriocin may be a potential target of mechanism-based therapy for this type of skin cancer.


Assuntos
Antineoplásicos/farmacologia , Ciclo Celular/efeitos dos fármacos , Ácidos Graxos Monoinsaturados/farmacologia , Melanoma Experimental/tratamento farmacológico , Serina C-Palmitoiltransferase/antagonistas & inibidores , Neoplasias Cutâneas/tratamento farmacológico , Animais , Proteína Quinase CDC2/biossíntese , Proteína Quinase CDC2/genética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ceramidas/biossíntese , Ceramidas/genética , Ciclina B1/biossíntese , Ciclina B1/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Lisofosfolipídeos/biossíntese , Lisofosfolipídeos/genética , Melanoma Experimental/genética , Camundongos , Proteínas Proto-Oncogênicas p21(ras)/biossíntese , Proteínas Proto-Oncogênicas p21(ras)/genética , Neoplasias Cutâneas/genética , Esfingomielinas/biossíntese , Esfingomielinas/genética , Esfingosina/análogos & derivados , Esfingosina/biossíntese , Esfingosina/genética , Proteína Supressora de Tumor p53/biossíntese , Proteína Supressora de Tumor p53/genética , Fosfatases cdc25/biossíntese , Fosfatases cdc25/genética
17.
Oncogene ; 30(30): 3345-59, 2011 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-21423208

RESUMO

Several studies have shown physiological functions of interleukin (IL)-32, a novel cytokine. However, the role of IL-32 in cancer development has not been reported. In this study, we showed that IL-32γ inhibited tumor growth in IL-32γ-overexpressing transgenic mice inoculated with melanoma as well as colon tumor growth in xenograft nude mice inoculated with IL-32γ-transfected colon cancer cells (SW620). The inhibitory effect of IL-32γ on tumor growth was associated with the inhibition of constitutive activated nuclear transcription factor-κB (NF-κB) and of signal transducer and activator of transcription 3 (STAT3). The expression of antiapoptotic, cell proliferation and tumor-promoting genes (bcl-2, X-chromosome inhibitor of apoptosis protein (IAP), cellular IAP and cellular FADD-like IL-1ß-converting enzyme-inhibitory protein, cyclin D), cyclin-dependent kinase 4, cycolooxygenase-2 and inducible nitric oxide synthase was decreased, whereas the expression of apoptotic target genes (caspase-3 and -9, bax) increased. In tumor, spleen and blood, the number of cytotoxic CD8(+) T cells and CD57(+) natural killer cells and the levels of IL-10 increased, but that of tumor necrosis factor-α (TNF-α), IL-1ß and IL-6 decreased. We also found that forced overexpression of IL-32γ inhibited colon cancer cell (SW620 and HCT116) growth accompanied with the inhibition of activated NF-κB and STAT3 in vitro. In addition, when IL-32γ was knocked down by small interfering RNA (siRNA) or neutralized with an anti-IL-32γ antibody, IL-32γ-induced colon cancer cell growth inhibition, the IL-32γ-induced decrease of TNF-α, IL-1 and IL-6 production, and the increase of IL-10 production were abolished. However, siRNA of NF-κB and STAT3 augmented IL-32γ-induced colon cancer cell growth inhibition. These findings indicate significant pathophysiological roles of IL-32γ in cancer development.


Assuntos
Neoplasias do Colo/patologia , Interleucinas/metabolismo , Melanoma/patologia , NF-kappa B/metabolismo , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Animais , Apoptose/genética , Linfócitos T CD8-Positivos/metabolismo , Proliferação de Células , Transformação Celular Neoplásica , Neoplasias do Colo/genética , Neoplasias do Colo/imunologia , Neoplasias do Colo/metabolismo , Citocinas/metabolismo , Inativação Gênica , Células HCT116 , Humanos , Interleucinas/genética , Células Matadoras Naturais/metabolismo , Masculino , Melanoma/genética , Melanoma/imunologia , Melanoma/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Transgênicos , Transdução de Sinais/genética
18.
Anat Histol Embryol ; 40(3): 210-8, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21323725

RESUMO

Gastrointestinal glutathione peroxidase (GI-GPx) is an antioxidant enzyme that has been known to be restricted to the gastrointestinal tract in rodents. In an effort to determine the expression pattern of GI-GPx mRNA during organogenesis, quantitative real-time PCR and in situ hybridization for GI-GPx mRNA were conducted in whole embryos or each developing organ of mice. GI-GPx mRNA was expressed more abundantly in the extraembryonic tissues, including placenta than in embryos on embryonic days (EDs) 7.5-18.5 (P < 0.05). When compared with the expression levels of cytosolic GPx (cGPx) mRNA, GI-GPx mRNA levels were low in the embryos, but relatively high in the extraembryonic tissues (P < 0.05). According to the results of whole mount in situ hybridizations, GI-GPx mRNA was principally expressed in the ectoplacental cone, neural tube and fold, and primitive heart at EDs 7.5-8.5. At EDs 9.5-12.5, GI-GPx mRNA was abundantly expressed in nervous tissues such as the telencephalon, mesencephalon and dorsal neural tube and was also detected in the forelimb and hindlimb at EDs 10.5-12.5. In the sectioned embryos after ED 13.5, GI-GPx mRNA levels were high in the cerebral cortex, metanephric corpuscle, pancreatic ducts, surface epithelia of the skin, inner ear, and nasal conchae, gastrointestinal tract, liver, urinary bladder, airway passages of lung, and whisker follicles. These findings indicate that GI-GPx is not only spatiotemporally expressed in a variety of embryonic organs during organogenesis but also may perform a mutual compensatory role with the cGPx in the protection of embryos and extraembryonic tissues against the reactive oxygen species generated in ontogenetic periods.


Assuntos
Embrião de Mamíferos/enzimologia , Trato Gastrointestinal/enzimologia , Regulação da Expressão Gênica no Desenvolvimento , Glutationa Peroxidase/genética , Organogênese , Animais , Membranas Extraembrionárias/enzimologia , Feminino , Trato Gastrointestinal/embriologia , Glutationa Peroxidase/biossíntese , Hibridização In Situ , Camundongos , Camundongos Endogâmicos ICR , Placenta/enzimologia , Reação em Cadeia da Polimerase , Gravidez , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Espécies Reativas de Oxigênio/metabolismo
19.
Minim Invasive Neurosurg ; 50(2): 86-90, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17674294

RESUMO

OBJECTIVE: This study compared the technical implications and clinical outcome of patients treated for an intracerebral hemorrhage using two minimally invasive procedures: frame-based stereotactic hematoma aspiration and frameless navigation-guided hematoma aspiration followed by fibrinolysis. METHODS: Thirty patients with a spontaneous supratentorial intracerebral hemorrhage, which was treated by a frame-based (n=15) and frameless (n=15) hematoma aspiration followed by subsequent fibrinolysis with urokinase, were retrospectively reviewed. The data for the two subsets of patients were analyzed with regard to hematoma reduction, Glasgow Coma Scale (GCS), and degree of weakness. RESULTS: In the frame-based stereotactic hematoma aspiration group, the volume of the hematoma was 15.4-100.0 mL (mean: 40.7+/-24.4), the GCS upon admission was 4-15 (mean: 10.1+/-3.0), and the grade of weakness upon admission was 1-5 (mean: 2.1+/-0.9). On the other hand, in the frameless navigation-guided hematoma aspiration group, the hematoma volume was 15.2-62.0 mL (mean: 30.0+/-15.2), the GCS upon admission was 7-15 (mean: 13.0+/-2.4), and the grade of weakness upon admission was 1-4 (mean: 2.3+/-1.2). The drainage catheter was in place for a mean duration of 5.1+/-2.4 days (range: 1-12 days). In the frame-based group, the initial hematoma was reduced by -115-88.5% (mean: 52+/-31.5) immediately after surgery, and 90.5% (41-100%) of the initial volume 14 days after surgery. In the frameless group, the initial hematoma was reduced by 11.7-90.8% (mean 57.3+/-25.1) immediately after surgery and 95.8% (87.7-100%) 14 days after surgery. The GCS score and the degree of weakness were evaluated 14 days after surgery, and the Glasgow outcome scale (GOS) score was evaluated at discharge. There were no statistically significant differences between the two groups. CONCLUSION: The frame-based group and the frameless group followed by fibrinolysis had similar outcomes, and both procedures effectively reduced the intracerebral hemorrhage volume within a short period of time. In addition, these procedures are simple, precise, safe, and brief with a very low rebleeding rate and mortality.


Assuntos
Hemorragia Cerebral/tratamento farmacológico , Hemorragia Cerebral/cirurgia , Fibrinolíticos/uso terapêutico , Hematoma/tratamento farmacológico , Hematoma/cirurgia , Neuronavegação/métodos , Técnicas Estereotáxicas/estatística & dados numéricos , Adolescente , Adulto , Idoso , Hemorragia Cerebral/patologia , Drenagem/instrumentação , Drenagem/métodos , Feminino , Escala de Coma de Glasgow , Hematoma/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Neuronavegação/estatística & dados numéricos , Hemorragia Pós-Operatória/prevenção & controle , Recidiva , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento , Ativador de Plasminogênio Tipo Uroquinase/uso terapêutico
20.
Acta Neurochir (Wien) ; 147(3): 343-5; discussion 345, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15605200
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