RESUMO
Recently, we have shown that (S)-N'-Nitrosonornicotine [(S)-NNN], the major form of NNN in tobacco products, is a potent oral cavity and esophageal carcinogen in rats. To determine the early molecular alterations induced by (S)-NNN in the oral and esophageal mucosa, we administered the carcinogen to rats in the drinking water for 10 wk and global gene expression alterations were analyzed by RNA sequencing. At a false discovery rate P-value < 0.05 and fold-change ≥2, we found alterations in the level of 39 genes in the oral cavity and 69 genes in the esophagus. Validation of RNA sequencing results by qRT-PCR assays revealed a high cross-platform concordance. The most significant impact of exposure to (S)-NNN was alteration of genes involved in immune regulation (Aire, Ctla4, and CD80), inflammation (Ephx2 and Inpp5d) and cancer (Cdkn2a, Dhh, Fetub B, Inpp5d, Ly6E, Nr1d1, and Wnt6). Consistent with the findings in rat tissues, most of the genes were deregulated, albeit to different degrees, in immortalized oral keratinocytes treated with (S)-NNN and in non-treated premalignant oral cells and malignant oral and head and neck squamous cells. Furthermore, interrogation of TCGA data sets showed that genes deregulated by (S)-NNN in rat tissues (Fetub, Ly6e, Nr1d1, Cacna1c, Cd80, and Dgkg) are also altered in esophageal and head and neck tumors. Overall, our findings provide novel insights into early molecular changes induced by (S)-NNN and, therefore, could contribute to the development of biomarkers for the early detection and prevention of (S)-NNN-associated oral and esophageal cancers. © 2016 Wiley Periodicals, Inc.
Assuntos
Carcinogênese/genética , Carcinógenos/toxicidade , Neoplasias Esofágicas/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Bucais/genética , Nitrosaminas/toxicidade , Transcriptoma , Animais , Carcinogênese/induzido quimicamente , Carcinógenos/administração & dosagem , Neoplasias Esofágicas/induzido quimicamente , Esôfago/efeitos dos fármacos , Esôfago/metabolismo , Humanos , Masculino , Boca/efeitos dos fármacos , Boca/metabolismo , Neoplasias Bucais/induzido quimicamente , Nitrosaminas/administração & dosagem , Ratos Endogâmicos F344RESUMO
Esophageal cancer-related gene 4 (ECRG4) has been proposed as a putative tumor suppressor gene in several tumors. However, the role and regulation of ECRG4 in the pathogenesis of human renal cancer remain largely unknown. Our current study revealed that expression of ECRG4 is downregulated in renal cell lines and renal cancer tissues. ECRG4 expression was significantly associated with histological grade of tumors (p < 0.001), primary tumor stage (p = 0.017), and distant metastasis (p = 0.017). Low expression of ECRG4 was an independent prognostic indicator for survival of renal cancer patients. Silencing of ECRG4 expression in renal cell lines was associated with its promoter methylation. Moreover, ectopic expression of ECRG4 markedly inhibited cell proliferation and invasion in renal cancer cell lines. These results indicated that ECRG4 is frequently silenced by the methylation of promoter in renal cell cancers. ECRG4 may be a tumor suppressor in renal cancer and serve as a prognostic marker.
Assuntos
Carcinoma de Células Renais/metabolismo , Metilação de DNA , Neoplasias Renais/metabolismo , Proteínas de Neoplasias/metabolismo , Regiões Promotoras Genéticas , Idoso , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Ilhas de CpG , DNA/química , Regulação para Baixo , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Prognóstico , Reação em Cadeia da Polimerase em Tempo Real , Proteínas Supressoras de TumorRESUMO
Chronic inflammation is an important risk factor for lung cancer. Therefore, identification of chemopreventive agents that suppress inflammation-driven lung cancer is indispensable. We studied the efficacy of combinations of indole-3-carbinol (I3C) and silibinin (Sil), 20 µmol/g diet each, against mouse lung tumors induced by 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) and driven by lipopolysaccharide (LPS), a potent inflammatory agent and constituent of tobacco smoke. Mice treated with NNK + LPS developed 14.7±4.1 lung tumors/mouse, whereas mice treated with NNK + LPS and given combinations of I3C and Sil had 7.1±4.5 lung tumors/mouse, corresponding to a significant reduction of 52%. Moreover, the number of largest tumors (>1.0mm) was significantly reduced from 6.3±2.9 lung tumors/mouse in the control group to 1.0±1.3 and 1.6±1.8 lung tumors/mouse in mice given I3C + Sil and I3C alone, respectively. These results were paralleled by significant reductions in the level of proinflammatory and procarcinogenic proteins (pSTAT3, pIκBα and COX-2) and proteins that regulate cell proliferation (pAkt, cyclin D1, CDKs 2, 4, 6 and pRB). Further studies in premalignant bronchial cells showed that the antiproliferative effects of I3C + Sil were higher than the individual compounds and these effects were mediated by targeting cyclin D1, CDKs 2, 4 and 6 and pRB. I3C + Sil suppressed cyclin D1 by reducing its messenger RNA level and by enhancing its proteasomal degradation. Our results showed the potential lung cancer chemopreventive effects of I3C + Sil in smokers/former smokers with chronic pulmonary inflammatory conditions.
Assuntos
Transformação Celular Neoplásica/efeitos dos fármacos , Indóis/farmacologia , Inflamação/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Silimarina/farmacologia , Animais , Anticarcinógenos/farmacologia , Proteínas de Ciclo Celular/biossíntese , Linhagem Celular Tumoral , Proliferação de Células , Quimioprevenção , Ciclina D1/biossíntese , Ciclina D1/genética , Quinases Ciclina-Dependentes/biossíntese , Ciclo-Oxigenase 2/biossíntese , Combinação de Medicamentos , Feminino , Humanos , Proteínas I-kappa B/biossíntese , Interleucina-6/biossíntese , Lipopolissacarídeos , Pulmão/patologia , Camundongos , Camundongos Endogâmicos A , Inibidor de NF-kappaB alfa , Nitrosaminas/efeitos adversos , Proteínas Proto-Oncogênicas c-akt/biossíntese , Distribuição Aleatória , Proteína do Retinoblastoma/biossíntese , Fator de Transcrição STAT3/biossíntese , Silibina , Fumaça/efeitos adversos , Fator de Necrose Tumoral alfa/biossínteseRESUMO
meso-Tetraphenylporphyrin (TPP) and its two substituted derivatives (meso-tetrakis(4-cyanophenyl)porphyrin [TPP(CN)4] and meso-tetrakis(4-methoxyphenyl)porphyrin [TPP(OMe)4]) were synthesized. Their nonlinear absorption and refraction properties were studied using the Z-scan technique in the picosecond (ps) and nanosecond (ns) regimes. The open aperture Z-scan results reveal that TPP and TPP(CN)4 display an identical reverse saturable absorption (RSA) character in the ps and ns regimes. While TPP(OMe)4 exhibits a transition from saturable absorption (SA) to RSA in the ps regime and a typical RSA character in the ns regime. The closed aperture Z-scan results show that TPP(CN)4 and TPP(OMe)4 have regular enhancement of the magnitude of nonlinear refraction as compared to their parent TPP in both the ps and ns regimes. In addition, the second-order molecular hyperpolarizabilities (γ) of these three porphyrins are calculated, and the γ values of TPP(CN)4 and TPP(OMe)4 are remarkable larger than that of TPP. The introduction of the electron-withdrawing group CN and the electron-donating group OMe into TPP has enhanced its nonlinear refraction and γ value, and tuned its nonlinear absorption (TPP(OMe)4), which could be useful for porphyrin-related applications based on the desired NLO properties.
Assuntos
Porfirinas/síntese química , Estrutura Molecular , Fenômenos Ópticos , Porfirinas/químicaRESUMO
INTRODUCTION: Chronic pulmonary inflammation has been consistently shown to increase the risk of lung cancer. Therefore, assessing the molecular links between the two diseases and identification of chemopreventive agents that inhibit inflammation-driven lung tumorigenesis is indispensable. MATERIALS AND METHODS: Female A/J mice were treated with the tobacco smoke carcinogen 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) and lipopolysaccharide (LPS), a potent inflammatory agent and constituent of tobacco smoke, and maintained on control diet or diet supplemented with the chemopreventive agents indole-3-carbinol (I3C) and/or silibinin (Sil). At the end of the study, mice were sacrificed and tumors on the surface of the lung were counted and gene expression levels in lung tissues were determined by RNA sequencing. RESULTS: The mean number of lung tumors induced by NNK and NNK + LPS was 5 and 15 tumors/mouse, respectively. Dietary supplementation with the combination of I3C and Sil significantly reduced the size and multiplicity (by 50 %) of NNK + LPS-induced lung tumors. Also, we found that 330, 2957, and 1143 genes were differentially regulated in mice treated with NNK, LPS, and NNK + LPS, respectively. The inflammatory response of lung tumors to LPS, as determined by the number of proinflammatory genes with altered gene expression or the level of alteration, was markedly less than that of normal lungs. Among 1143 genes differentially regulated in the NNK + LPS group, the expression of 162 genes and associated signaling pathways was significantly modulated by I3C and/or Sil + I3C. These genes include cytokines, chemokines, putative oncogenes and tumor suppressor genes and Ros1, AREG, EREG, Cyp1a1, Arntl, and Npas2. CONCLUSION: To our knowledge, this is the first report that provides insight into genes that are differentially expressed during inflammation-driven lung tumorigenesis and the modulation of these genes by chemopreventive agents.
Assuntos
Anticarcinógenos/farmacologia , Regulação Neoplásica da Expressão Gênica/genética , Inflamação/complicações , Inflamação/genética , Neoplasias Pulmonares/etiologia , Neoplasias Pulmonares/genética , Animais , Carcinógenos/farmacologia , Feminino , Indóis/farmacologia , Lipopolissacarídeos/farmacologia , Pulmão/patologia , Camundongos , Camundongos Endogâmicos A , RNA/biossíntese , RNA/genética , Análise de Sequência de RNA , Silibina , Silimarina/farmacologiaRESUMO
The graphdiyne (GD), a carbon allotrope with a 2D structure comprising benzene rings and carbon-carbon triple bonds, can be synthesized through cross-coupling on the surface of copper foil. The key problem is in understanding the dependence of layers number and properties, however, the controlled growth of the layers numbers of GD film have not been demonstrated, its controlled growth into large-area and high ordered films with different numbers of layers is still an important challenge. Here, we show that a new strategy for synthesizing GD films with 2D nanostructures on ZnO nanorod arrays through a combination of reduction and a self-catalyzed vapor-liquid-solid growth process, using GD powder as the vapor source and ZnO nanorod arrays as the substrate. HRTEM shows the distance between pairs of streaks being approximately 0.365â nm by different thicknesses of GD films. The approach enables us to construct large-area ordered semiconductive films with high-quality surfaces showing high conductivity (up to 2800â S cm(-1)). FETs were fabricated based on the well ordered films; we prepared and measured over 100 devices. Devices incorporating these well-ordered and highly conductive GD films exhibited field-effect mobility as high as 100â cm(2) V(-1)â s(-1).
RESUMO
Inflammatory conditions of the lung such as chronic obstructive pulmonary disease (COPD) are known to increase lung cancer risk, particularly lung squamous cell carcinoma (LSCC). In the present study, we developed a mouse model of inflammation-driven LSCC that was induced by N-nitroso-trischloroethylurea (NTCU) and enhanced by lipopolysaccharide (LPS), a potent proinflammatory agent contained in tobacco and tobacco smoke, and determined the chemopreventive effects of BioResponse diindolylmethane (DIM) in the same model. Compared with mice treated with NTCU alone, mice treated with the combination of NTCU and LPS had a 9-fold increase in the number of bronchioles with LSCC. Also, compared with mice treated with LPS alone, mice treated with NTCU plus LPS showed significantly increased expression of the inflammatory cytokines IL1α, IL6, and TNFα (all three increased about 7-fold). Parallel to the increased cytokine gene expression, the NTCU plus LPS-treated group exhibited significantly enhanced activation of NF-κB, STAT3, ERK, p-38, and Akt, expression of p53, COX-2, and Mcl-1, and NF-κB- and STAT3-DNA binding in the lung. Dietary administration of DIM (10 µmol/g diet or 2,460 ppm) to mice treated with NTCU plus LPS reduced the incidence of LSCC by 2-fold, suppressed activation/expression of proinflammatory and procarcinogenic proteins and NF-κB- and STAT3-DNA binding, but not the expression of cytokines and p53. This study highlights the potential significance of our mouse model to identify promising drugs or dietary agents for the chemoprevention of human LSCC and that DIM is a very good candidate for clinical lung cancer chemoprevention trials.
Assuntos
Carcinoma de Células Escamosas/tratamento farmacológico , Indóis/administração & dosagem , Inflamação/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Animais , Carmustina/análogos & derivados , Carmustina/química , Citocinas/metabolismo , Dieta , Modelos Animais de Doenças , Feminino , Regulação Neoplásica da Expressão Gênica , Indóis/química , Lipopolissacarídeos/química , Pulmão/metabolismo , Neoplasias Pulmonares/metabolismo , Camundongos , NF-kappa B/metabolismoRESUMO
Indole-3-carbinol (I3C), a constituent of commonly consumed Brassica vegetables, has been shown to have anticancer effects in a variety of preclinical models of lung cancer. However, it has shown only limited efficacy in clinical trials, likely due to its poor oral bioavailability. Intranasal administration of I3C has the potential to enhance the pulmonary accumulation of the drug, thereby improving its availability at the target site of action. In this study, we developed a liposomal formulation of I3C and evaluated its lung delivery and chemopreventive potential in tobacco smoke carcinogen [4-(methylnitro-samino)-1-(3-pyridyl)-1-butanone (NNK)]-treated mice. Intranasal administration of I3C liposomes led to a â¼100-fold higher lung exposure of I3C than the oral route of administration. Further, intranasal delivery of liposomal I3C led to a significant reduction (37%; p<0.05) in the levels of the DNA adduct formation induced by NNK treatment. Liposomal I3C also significantly increased (by 10-fold) the expression of CYP1A1, a cytochrome P450 enzyme known to increase the detoxification of chemical carcinogens by enhancing their metabolism. Overall, our findings demonstrate that intranasal administration of liposomal I3C has the potential to significantly improve the efficacy of I3C for lung cancer chemoprevention.
Assuntos
Anticarcinógenos/administração & dosagem , Sistemas de Liberação de Medicamentos , Indóis/administração & dosagem , Neoplasias Pulmonares/prevenção & controle , Administração Intranasal , Administração Oral , Animais , Anticarcinógenos/farmacocinética , Disponibilidade Biológica , Carcinógenos/toxicidade , Citocromo P-450 CYP1A1/genética , Feminino , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Indóis/farmacocinética , Lipossomos , Pulmão/metabolismo , Camundongos , Nitrosaminas/toxicidade , Distribuição TecidualRESUMO
We developed a new method combining the in situ liquid-solid phase reaction and self-assembly in solution to synthesize novel inorganic/organic small molecular semiconductor core-shell nanoparticles of ZnS/PTCDA (ZPNPs). This method is a one-step process which can produce stoichiometric inorganic/organic core-shell nanoparticles and does not introduce any impurity. The film of ZPNPs exhibited an ultrasensitive detection of aniline vapor. The film of ZPNPs can highly selectively distinguish aniline vapor from many volatile organic compounds and water due to the strong synergistic interactions of π-π and hydrogen-bonds between electron donor (aniline) and acceptor (PTCDA) molecules, in which the detection limit was lowered to 100 ppb at room temperature.
RESUMO
In this study, we constructed a novel solid state supramolecular system-the molecular cage ZnOTCPP, based on an inorganic/organic hybrid nanostructure, through the assembly of 5,10,15,20-tetra(3-carboxyphenyl)porphyrin (TCPP) onto the surfaces of ZnO nanorod (NR) arrays. The ZnOTCPP molecular cage exhibited highly selective recognition of 5,10,15,20-tetraphenylporphyrin (TPP) by optical and photoelectrical signals. The ZnOTCPP@TPP exhibited high emission efficiency, with a six-fold increase in the intensity of the emission relative to that of ZnOTCPP after the molecular cage ZnOTCPP captured TPP. The optical, electrical, and optoelectrical properties of the molecular cage ZnOTCPP could be controlled by tuning the interactions between the guest and the host's inorganic or organic moieties. Such a solid state molecular cage opens the door to controlled-delivery applications and provides an attractive platform for studying solid state supramolecular electronics and optoelectronics.
RESUMO
Lung cancer is the most fatal cancer and development of agents that suppress lung tumorigenesis is a crucial strategy to reduce mortality related to this disease. In the present study, we showed, using an in vitro model of lung tumorigenesis, that dimethylamino-parthenolide (DMAPT), a water soluble parthenolide analog, selectively inhibited the growth and survival of premalignant and malignant cells with minimal effects on parental immortalized cells. These effects were paralleled by suppression of pSTAT3, Mcl-1 and cyclin D1 and PARP cleavage, suggesting that the antiproliferative and apoptotic effects of DMAPT could be mediated, at least in part, via suppression of the STAT3 signaling pathway. Moreover, in tobacco smoke carcinogen-induced lung tumor bioassay in mice, intranasal instillation of low doses of DMAPT significantly reduced the overall lung tumor multiplicity by 39%. Interestingly, the drug was specifically effective (62% reduction) against bigger lung tumors (> 2 mm), which have a higher potential to develop into lung adenocarcinoma. Western immunoblotting analyses of mouse lung tissues indicated significantly lower level of pSTAT3 and Mcl-1 in the carcinogen plus DMAPT group relative to the group treated with the carcinogen only. Given the evidence that STAT3 is activated in more than half of lung cancers and it regulates genes involved in cell proliferation, survival and angiogenesis, DMAPT is a promising agent for lung cancer chemoprevention in subjects who are at high risk of developing this devastating disease.
Assuntos
Antineoplásicos/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , Fator de Transcrição STAT3/metabolismo , Sesquiterpenos/farmacologia , Animais , Apoptose/efeitos dos fármacos , Brônquios/patologia , Linhagem Celular/efeitos dos fármacos , Linhagem Celular/patologia , Transformação Celular Neoplásica/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Feminino , Humanos , Neoplasias Pulmonares/induzido quimicamente , Camundongos , Camundongos Endogâmicos , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Nitrosaminas/toxicidade , SolubilidadeRESUMO
Consideration of the material design and components match on structure and energy, the solid-solid combined nanowires of p-type conductive polymer of poly[3-thiophene carboxylic acid methyl ester] (PTCM) and n-type inorganic semiconductor PbS was prepared with a 2.57 µm(2) heterojunction interface. The axial deeply inserting heterojunction nanowire arrays exhibited excellent rectifying features and diode nature, as well as obvious electrical switching behavior, which are much excelled individual components of PTCM and PbS nanowire arrays for realizing synergistic performance.
RESUMO
Large-area and ordered arrays (16 cm(2)) of an inorganic-organic p-n heterojunction nanotree (NT) were successfully fabricated. The nanotree arrays consist of ZnO nanorods (NRs) as backbones and CuTCNQ (TCNQ = 7,7,8,8-tetracyanoquinodimethane) NRs as branches. The sizes of CuTCNQ NRs can be tuned by the thickness of the Cu layer deposited on the surface of ZnO NR. The CuTCNQ/ZnO NT arrays displayed excellent diode nature and obvious size-dependent rectification ratios were observed. Moreover, the CuTCNQ/ZnO NT arrays were first applied for the fabrication of a diode-type humidity sensor, which displayed ultrahigh sensitivity and quick response/recovery properties at room temperature. The detection limitation of this new diode-type humidity sensor lowers to 5% relative humidity (RH).
Assuntos
Nanoestruturas/química , Nanotecnologia/instrumentação , Vapor/análise , Cobre/química , Monitoramento Ambiental/instrumentação , Umidade , Microscopia Eletrônica de Varredura , Nanoestruturas/ultraestrutura , Nanotecnologia/métodos , Nitrilas/química , Sensibilidade e Especificidade , Óxido de Zinco/químicaRESUMO
Lung cancer is the leading cause of cancer death in the world. Evidence suggests that lung cancer could originate from mutations accumulating in a subpopulation of self-renewing cells, lung stem cells. Aldehyde dehydrogenase (ALDH) is a marker of stem cells. To investigate the presence of DNA modifications in these cells, we isolated ALDH-positive lung cells from A/J mice exposed to the lung carcinogen 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone. Using LC-NSI-HRMS/MS-PRM, O(6)-methyl-G, 7-POB-G, and O(2)-POB-dT were positively identified in ALDH-positive cell DNA. This is the first example of detection of carcinogen-DNA adducts in lung stem cells, supporting the hypothesis of their role in lung carcinogenesis.
Assuntos
Carcinógenos/toxicidade , Adutos de DNA , Nitrosaminas/toxicidade , Células-Tronco/metabolismo , Aldeído Desidrogenase/metabolismo , Animais , Feminino , Pulmão/citologia , Pulmão/metabolismo , Neoplasias Pulmonares/metabolismo , Camundongos , NicotianaRESUMO
Large area (26.7 cm2) nanotip arrays of porous conducting poly [5, 10, 15, 20-tetra (4-ethynylphenyl) porphyrin] diyne (TEPPD) have been successfully fabricated by an in situ cross-coupling reaction on the surface of the copper foil, which will open a new routine for large-area nanofabrication of porous conducting polymer on a conducting substrate. The surface-area of TEPPD nanotip arrays is up to 146 m2/g. Interestingly, the nanotip arrays of TEPPD display a good field-emission property and exhibit a better stability of field emission than that of organic and polymeric nanostructures because of the good heat radiation of porous, which is comparable to some important nanostructures of inorganic semiconductor. The porous conducting polymer could be used for new field-emission emitter and other molecular electronic devices.
RESUMO
Tobacco smoking is a risk factor for cancers of the liver and gastrointestinal (GI) tract, but the causal agents responsible for these cancers are uncertain. 2-Amino-9H-pyrido[2,3-b]indole (AαC) is an abundant heterocyclic aromatic amine present in tobacco smoke. AαC is a liver carcinogen and both a transgene mutagen and inducer of aberrant crypt foci in the colon of mice. We hypothesize that AαC may contribute to DNA damage and tumorigenesis in these organs of smokers. The potential of AαC to induce DNA adduct formation in liver, organs of the GI tract, lung, and urinary bladder, which are target organs of cancer in smokers, was examined using the C57BL/6 mouse as an animal model. AαC (400 or 800 ppm) and 2-amino-3,4-dimethylimidazo[4,5-f]quinoline (MeIQ) (300 ppm), a liver and colon carcinogen in C57BL/6 mice, were given in the diet for up to 12 weeks. Liquid chromatography/mass spectrometry was employed to measure DNA adducts. The major DNA adducts of both carcinogens were identified as deoxyguanosine-C8 adducts. The levels of formation of AαC- and MeIQ-DNA adducts were similar in liver and extrahepatic tissues when adjusted for dose. The highest levels of adducts occurred in liver, followed by urinary bladder, and then in cecum and colon; lower DNA adduct levels were formed in the lung and pancreas following 12 weeks of feeding. The high levels of AαC adduct formed in liver, GI tract, and bladder of C57BL/6 mice reinforce the notion that AαC may contribute to DNA damage and cancer of these organs in smokers.
Assuntos
Carbolinas/toxicidade , Carcinógenos/toxicidade , Adutos de DNA/metabolismo , Trato Gastrointestinal/efeitos dos fármacos , Fígado/efeitos dos fármacos , Pulmão/efeitos dos fármacos , Quinolinas/toxicidade , Bexiga Urinária/efeitos dos fármacos , Animais , Carbolinas/metabolismo , Carcinógenos/metabolismo , Dano ao DNA , Feminino , Trato Gastrointestinal/metabolismo , Fígado/metabolismo , Pulmão/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Quinolinas/metabolismo , Testes de Toxicidade , Bexiga Urinária/metabolismoRESUMO
The main reasons for the failure of most chemopreventive agents during clinical trials are poor in vivo bioavailability and dose-limiting side effects. One potential approach to surmount these problems in lung cancer chemoprevention trials could be direct delivery of agents into the pulmonary tissue. In this study, we assessed the efficacy of intranasally delivered bio-response diindolylmethane (BRD) against 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK)-induced lung tumorigenesis in mice. Mice treated with NNK (two doses of 50mg/kg at an interval of a week, intraperitoneal) developed 16.3±2.9 lung tumors per mouse. Post-carcinogen administration of BRD, via intranasal instillation, for 24 weeks, twice a week, at a dose of 2mg per mouse (0.6mg pure diindolylmethane per mouse) reduced the lung tumor multiplicity to 4.6±2.2 tumors per mouse (72% reduction). Likewise, large tumors (>1mm) were almost completely abolished and multiplicities of tumors with a size of 0.5-1mm were reduced by 74%. Tumor volume was also reduced by 82%. Further studies using an in vitro model of lung tumorigenesis showed that BRD exhibited pronounced antiproliferative and apoptotic effects in premalignant and malignant bronchial cells but only minimal effects in parental immortalized cells through, at least in part, suppression of the phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway. These results showed the potent lung tumor inhibitory activities of low doses of BRD given via intranasal instillation and, therefore, intranasal delivery of BRD holds a great promise for lung cancer chemoprevention in subjects at high risk to develop lung cancer.
Assuntos
Indóis/administração & dosagem , Neoplasias Pulmonares/prevenção & controle , Administração Intranasal , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Transformação Celular Neoplásica/efeitos dos fármacos , Feminino , Humanos , Indóis/uso terapêutico , Neoplasias Pulmonares/induzido quimicamente , Neoplasias Pulmonares/tratamento farmacológico , Camundongos , Camundongos Endogâmicos A , Nitrosaminas , Fosfatidilinositol 3-Quinase/metabolismo , Distribuição AleatóriaRESUMO
One-dimensional nanostructures of the organic charge-transfer (CT) complex CuTNAP (copper 11,11,12,12-tetracyano-2,6-naphthoquinodimethane) were successfully synthesized by an organic vapor-solid phase reaction. The morphologies and field-emission properties of the CuTNAP nanostructures can be easily tuned by controlling the reaction conditions. It was observed that the field emission property is dependent on the morphology. The current density of a CuTNAP film of nanowires reaches up to 13.1 mA cm(-2), which is the highest among the organic semiconductors, even higher than most inorganic materials. These results demonstrate that the CuTNAP complex nanostructures are excellent potential candidates as field emitters.
RESUMO
CuS/PbS p-n heterojunction nanowires arrays have been successfully synthesized. Association of template and DC power sources by controllable electrochemistry processes offers a technique platform to efficiently grow a combined heterojunction nanowire arrays driven by a minimization of interfacial energy. The resulting p-n junction materials of CuS/PbS show highly uniform 1D wire architecture. The single CuS/PbS p-n heterojunction nanowire based devices were fabricated, and their electrical behaviors were investigated. The independent nanowires exhibited a very high ON/OFF ratio of 1195, due to the association effect of electrical switches and diodes.
RESUMO
Coordination polymers PZn quantum dots with a uniform diameter of 3 ± 0.5 nm were successfully prepared. The PZn QDs exhibit excellent water dispersibility, high photoluminescence, outstanding photostability and remarkable biocompatibility. The results of cellular experiments show that the PZn QDs are highly suitable for long-term cell imaging.