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1.
Diagnostics (Basel) ; 13(7)2023 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-37046510

RESUMO

An important consideration in medical plastic surgery is the evaluation of the patient's facial symmetry. However, because facial attractiveness is a slightly individualized cognitive experience, it is difficult to determine face attractiveness manually. This study aimed to train a model for assessing facial attractiveness using transfer learning while also using the fine-grained image model to separate similar images by first learning features. In this case, the system can make assessments based on the input of facial photos. Thus, doctors can quickly and objectively treat patients' scoring and save time for scoring. The transfer learning was combined with CNN, Xception, and attention mechanism models for training, using the SCUT-FBP5500 dataset for pre-training and freezing the weights as the transfer learning model. Then, we trained the Chang Gung Memorial Hospital Taiwan dataset to train the model based on transfer learning. The evaluation uses the mean absolute error percentage (MAPE) value. The root mean square error (RMSE) value is used as the basis for experimental adjustment and the quantitative standard for the model's predictive. The best model can obtain 0.50 in RMSE and 18.5% average error in MAPE. A web page was developed to infer the deep learning model to visualize the predictive model.

2.
Sci Rep ; 12(1): 20133, 2022 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-36418355

RESUMO

This study was to determine the significance of factors considered for the measurement accuracy of personal dosimeter in dosimetry services such as dosimetry service, irradiation category, years of use and readout frequency. The investigation included management information questionnaire, on-site visit and blind test. The blind test with random selected personal badge was used in inter-comparison of eight dosimetry services, and the test results followed ANSI/HPS N13.11 criteria. This study also analyzed the measurement deviations if they felt in the criteria of ICRP 75 or not. One-way ANOVA tests were used to analyze the significant difference of the measurement deviations in different dosimetry services, irradiation categories, and years of use. Simple linear-regression test was performed for the significance of the prediction model between measurement deviations and readout frequencies. All visited dosimetry services followed the proper statue of basic management and passed the performance check of the tolerance level. The average deviations corresponding to category I, category II deep dose, and category II shallow dose were 6.08%, 9.49%, and 10.41% respectively. There had significant differences of measurement deviation in different dosimetry services (p < 0.0001) and irradiation categories (p = 0.016) but no significant difference in years of use (p = 0.498). There was no significance in the linear-regression model between measurement deviation and badge readout frequencies. Based on the regular calibration of the personal dosimeter, the deviation of the measured value is mainly affected by different dosimetry services and irradiation categories; and there shows no significant influence by years of use and readout frequency.


Assuntos
Dosímetros de Radiação , Radiometria , Calibragem , Análise de Variância
3.
Adv Healthc Mater ; 10(11): e2100024, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33890420

RESUMO

Scaffolds for tissue engineering aim to mimic the native extracellular matrix (ECM) that provides physical support and biochemical signals to modulate multiple cell behaviors. However, the majority of currently used biomaterials are oversimplified and therefore fail to provide a niche required for the stimulation of tissue regeneration. In the present study, 3D decellularized ECM (dECM) scaffolds derived from mesenchymal stem cell (MSC) spheroids and with intricate matrix composition are developed. Specifically, application of macromolecular crowding (MMC) to MSC spheroid cultures facilitate ECM assembly in a 3D configuration, resulting in the accumulation of ECM and associated bioactive components. Decellularized 3D dECM constructs produced under MMC are able to adequately preserve the microarchitecture of structural ECM components and are characterized by higher retention of growth factors. This results in a stronger proangiogenic bioactivity as compared to constructs produced under uncrowded conditions. These dECM scaffolds can be homogenously populated by endothelial cells, which direct the macroassembly of the structures into larger cell-carrying constructs. Application of empty scaffolds enhances intrinsic revascularization in vivo, indicating that the 3D dECM scaffolds represent optimal proangiogenic bioactive blocks for the construction of larger engineered tissue constructs.


Assuntos
Células-Tronco Mesenquimais , Engenharia Tecidual , Células Endoteliais , Matriz Extracelular , Células-Tronco , Alicerces Teciduais
5.
Microsyst Nanoeng ; 6: 2, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-34567617

RESUMO

Conventional electroporation approaches show limitations in the delivery of macromolecules in vitro and in vivo. These limitations include low efficiency, noticeable cell damage and nonuniform delivery of cells. Here, we present a simple 3D electroporation platform that enables massively parallel single-cell manipulation and the intracellular delivery of macromolecules and small molecules. A pyramid pit micropore array chip was fabricated based on a silicon wet-etching method. A controllable vacuum system was adopted to trap a single cell on each micropore. Using this chip, safe single-cell electroporation was performed at low voltage. Cargoes of various sizes ranging from oligonucleotides (molecular beacons, 22 bp) to plasmid DNA (CRISPR-Cas9 expression vectors, >9 kb) were delivered into targeted cells with a significantly higher transfection efficiency than that of multiple benchmark methods (e.g., commercial electroporation devices and Lipofectamine). The delivered dose of the chemotherapeutic drug could be controlled by adjusting the applied voltage. By using CRISPR-Cas9 transfection with this system, the p62 gene and CXCR7 gene were knocked out in tumor cells, which effectively inhibited their cellular activity. Overall, this vacuum-assisted micropore array platform provides a simple, efficient, high-throughput intracellular delivery method that may facilitate on-chip cell manipulation, intracellular investigation and cancer therapy.

6.
ACS Appl Nano Mater ; 2(10): 6249-6257, 2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-33585803

RESUMO

Targeting therapeutic agents to specific organs in the body remains a challenge despite advances in the science of systemic drug delivery. We have engineered a programmable-bioinspired nanoparticle (P-BiNP) delivery system to simultaneously target the bone and increase uptake in homotypic tumor cells by coating polymeric nanoparticles with programmed cancer cell membranes. This approach is unique in that we have incorporated relevant clinical bioinformatics data to guide the design and enhancement of biological processes that these nanoparticles are engineered to mimic. To achieve this, an analysis of RNA expression from metastatic prostate cancer patients identified ITGB3 (a subunit of integrin α V ß 3) as overexpressed in patients with bone metastasis. Cancer cells were stimulated to increase this integrin expression on the cell surface, and these membranes were subsequently used to coat cargo carrying polymeric nanoparticles. Physicochemical optimization and characterization of the P-BiNPs showed desirable qualities regarding size, ζ potential, and stability. In vitro testing confirmed enhanced homotypic binding and uptake in cancer cells. P-BiNPs also demonstrated improved bone localization in vivo with a murine model. This novel approach of identifying clinically relevant targets for dual homotypic and bone targeting has potential as a strategy for treatment and imaging modalities in diseases that affect the bone as well as broader implications for delivering nanoparticles to other organs of interest.

7.
Br J Cancer ; 119(12): 1538-1551, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30385822

RESUMO

BACKGROUND: Although NGLY1 is known as a pivotal enzyme that catalyses the deglycosylation of denatured glycoproteins, information regarding the responses of human cancer and normal cells to NGLY1 suppression is limited. METHODS: We examined how NGLY1 expression affects viability, tumour growth, and responses to therapeutic agents in melanoma cells and an animal model. Molecular mechanisms contributing to NGLY1 suppression-induced anticancer responses were revealed by systems biology and chemical biology studies. Using computational and medicinal chemistry-assisted approaches, we established novel NGLY1-inhibitory small molecules. RESULTS: Compared with normal cells, NGLY1 was upregulated in melanoma cell lines and patient tumours. NGLY1 knockdown caused melanoma cell death and tumour growth retardation. Targeting NGLY1 induced pleiotropic responses, predominantly stress signalling-associated apoptosis and cytokine surges, which synergise with the anti-melanoma activity of chemotherapy and targeted therapy agents. Pharmacological and molecular biology tools that inactivate NGLY1 elicited highly similar responses in melanoma cells. Unlike normal cells, melanoma cells presented distinct responses and high vulnerability to NGLY1 suppression. CONCLUSION: Our work demonstrated the significance of NGLY1 in melanoma cells, provided mechanistic insights into how NGLY1 inactivation leads to eradication of melanoma with limited impact on normal cells, and suggested that targeting NGLY1 represents a novel anti-melanoma strategy.


Assuntos
Antineoplásicos/farmacologia , Apoptose , Interferon gama/fisiologia , Melanoma/tratamento farmacológico , Peptídeo-N4-(N-acetil-beta-glucosaminil) Asparagina Amidase/antagonistas & inibidores , Fator 4 Ativador da Transcrição/fisiologia , Animais , Células Cultivadas , Citocinas/análise , Perfilação da Expressão Gênica , Humanos , Interferon gama/genética , Melanoma/patologia , Camundongos , Peptídeo-N4-(N-acetil-beta-glucosaminil) Asparagina Amidase/fisiologia , Células-Tronco Pluripotentes/fisiologia , Complexo de Endopeptidases do Proteassoma/fisiologia , Transdução de Sinais/fisiologia , Fator de Transcrição CHOP/fisiologia
8.
Stem Cells ; 35(3): 626-640, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28009074

RESUMO

The study and application of human pluripotent stem cells (hPSCs) will be enhanced by the availability of well-characterized monoclonal antibodies (mAbs) detecting cell-surface epitopes. Here, we report generation of seven new mAbs that detect cell surface proteins present on live and fixed human ES cells (hESCs) and human iPS cells (hiPSCs), confirming our previous prediction that these proteins were present on the cell surface of hPSCs. The mAbs all show a high correlation with POU5F1 (OCT4) expression and other hPSC surface markers (TRA-160 and SSEA-4) in hPSC cultures and detect rare OCT4 positive cells in differentiated cell cultures. These mAbs are immunoreactive to cell surface protein epitopes on both primed and naive state hPSCs, providing useful research tools to investigate the cellular mechanisms underlying human pluripotency and states of cellular reprogramming. In addition, we report that subsets of the seven new mAbs are also immunoreactive to human bone marrow-derived mesenchymal stem cells (MSCs), normal human breast subsets and both normal and tumorigenic colorectal cell populations. The mAbs reported here should accelerate the investigation of the nature of pluripotency, and enable development of robust cell separation and tracing technologies to enrich or deplete for hPSCs and other human stem and somatic cell types. Stem Cells 2017;35:626-640.


Assuntos
Anticorpos Monoclonais/imunologia , Proteínas de Membrana/imunologia , Células-Tronco Pluripotentes/metabolismo , Animais , Antígenos de Superfície/metabolismo , Técnicas de Cultura de Células , Diferenciação Celular , Autorrenovação Celular , Regulação para Baixo/genética , Corpos Embrioides/citologia , Corpos Embrioides/metabolismo , Citometria de Fluxo , Células-Tronco Hematopoéticas/metabolismo , Humanos , Proteínas de Membrana/metabolismo , Camundongos , Fator 3 de Transcrição de Octâmero/metabolismo
9.
World J Surg Oncol ; 14(1): 190, 2016 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-27450394

RESUMO

BACKGROUND: Desmoid tumors (DTs) are non-metastatic, locally aggressive neoplasms with high postoperative recurrence rates. The pancreas is an extremely rare location for DTs. The local control of DTs is challenging. Surgery and radiotherapy are currently the principal treatment modalities for DTs; however, some resections might not be radical, and radiotherapy has several drawbacks. Therefore, many studies have been focusing on the molecular pathways involved in DTs in order to develop molecular-targeted therapies or chemotherapy. Cyclooxygenase-2 (COX-2) has been demonstrated to play a role in the growth of DTs, and the pharmacologic blockade of COX resulted in decreased cell proliferation in desmoid cell cultures in vitro. CASE PRESENTATION: Herein, we report a 57-year-old woman who presented with recurrent epigastric pain and weight loss. An abdominal computed tomography scan showed an approximately 10-cm mass over the pancreatic head region and dilatation of the pancreatic duct. Tumor biopsy and bypass surgery were performed. A DT was confirmed on pathologic analysis. After resection, we prescribed treatment with the COX-2 inhibitor celecoxib. The patient showed complete remission and there was no local recurrence or distant metastasis within the 24-month follow-up period. CONCLUSIONS: The outcome of this case study is encouraging, and long-term follow-up studies are required to establish the effect of treatment with celecoxib on the prognosis of DTs.


Assuntos
Dor Abdominal/tratamento farmacológico , Inibidores de Ciclo-Oxigenase 2/uso terapêutico , Fibromatose Agressiva/tratamento farmacológico , Neoplasias Pancreáticas/tratamento farmacológico , Feminino , Humanos , Pessoa de Meia-Idade , Prognóstico , Indução de Remissão
10.
Expert Opin Biol Ther ; 15(5): 679-87, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25736263

RESUMO

INTRODUCTION: Human pluripotent stem cells (hPSCs) promise for the future of regenerative medicine. The structural and biochemical diversity associated with glycans makes them a unique type of macromolecule modification that is involved in the regulation of a vast array of biochemical events and cellular activities including pluripotency in hPSCs. The primary focus of this review article is to highlight recent advances in stem cell research from a glycobiological perspective. We also discuss how our understanding of glycans and glycosylation may help overcome barriers hindering the clinical application of hPSC-derived cells. AREAS COVERED: A literature survey using NCBI-PubMed and Google Scholar was performed in 2014. EXPERT OPINION: Regenerative medicine hopes to provide novel strategies to combat human disease and tissue injury that currently lack effective therapies. Although progress in this field is accelerating, many critical issues remain to be addressed in order for cell-based therapy to become a practical and safe treatment option. Emerging evidence suggests that protein glycosylation may significantly influence the regulation of cellular pluripotency, and that the exploitation of protein glycosylation in hPSCs and their differentiated derivatives may lead to transformative and translational discoveries for regenerative medicine. In addition, hPSCs represent a novel research platform for investigating glycosylation-related disease.


Assuntos
Células-Tronco Pluripotentes/transplante , Medicina Regenerativa/tendências , Transplante de Células-Tronco/tendências , Diferenciação Celular/fisiologia , Células-Tronco Embrionárias/fisiologia , Células-Tronco Embrionárias/transplante , Glicosilação , Humanos , Células-Tronco Pluripotentes/fisiologia , Medicina Regenerativa/métodos , Transplante de Células-Tronco/métodos
11.
PLoS One ; 10(2): e0118307, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25714340

RESUMO

The self-renewal and differentiation capacities of human pluripotent stem cells (hPSCs) make them a promising source of material for cell transplantation therapy, drug development, and studies of cellular differentiation and development. However, the large numbers of cells necessary for many of these applications require extensive expansion of hPSC cultures, a process that has been associated with genetic and epigenetic alterations. We have performed a combinatorial study on both hESCs and hiPSCs to compare the effects of enzymatic vs. mechanical passaging, and feeder-free vs. mouse embryonic fibroblast feeder substrate, on the genetic and epigenetic stability and the phenotypic characteristics of hPSCs. In extensive experiments involving over 100 continuous passages, we observed that both enzymatic passaging and feeder-free culture were associated with genetic instability, higher rates of cell proliferation, and persistence of OCT4/POU5F1-positive cells in teratomas, with enzymatic passaging having the stronger effect. In all combinations of culture conditions except for mechanical passaging on feeder layers, we noted recurrent deletions in the genomic region containing the tumor suppressor gene TP53, which was associated with decreased mRNA expression of TP53, as well as alterations in the expression of several downstream genes consistent with a decrease in the activity of the TP53 pathway. Among the hESC cultures, we also observed culture-associated variations in global gene expression and DNA methylation. The effects of enzymatic passaging and feeder-free conditions were also observed in hiPSC cultures. Our results highlight the need for careful assessment of the effects of culture conditions on cells intended for clinical therapies.


Assuntos
Epigênese Genética , Genoma Humano , Instabilidade Genômica , Células-Tronco Embrionárias Humanas/metabolismo , Técnicas de Cultura de Células , Diferenciação Celular , Linhagem Celular , Autorrenovação Celular , Transformação Celular Neoplásica/genética , Células Cultivadas , Aberrações Cromossômicas , Deleção Cromossômica , Duplicação Cromossômica , Cromossomos Humanos Par 12 , Cromossomos Humanos Par 17 , Cromossomos Humanos Par 20 , Metilação de DNA , Perfilação da Expressão Gênica , Células-Tronco Embrionárias Humanas/citologia , Células-Tronco Embrionárias Humanas/patologia , Humanos , Fenótipo , Células-Tronco Pluripotentes/metabolismo , Polimorfismo de Nucleotídeo Único , Fatores de Tempo , Proteína Supressora de Tumor p53/genética
12.
J Chin Med Assoc ; 76(6): 330-4, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23602592

RESUMO

BACKGROUND: Continuous passive motion after a major knee surgery optimizes functional prognosis, but causes severe pain. In this study, we assessed the effect of intravenous patient-controlled analgesia (IVPCA) on postoperative pain management in unilateral and bilateral total knee arthroplasty (TKA). METHODS: Data were collected retrospectively from a single medical center from March 2003 to October 2007. All patients who had undergone TKA were given general anesthesia, and the type of surgery that each patient received was planned according to individual needs. A total of 223 patients qualified for this study, with 174 patients in the unilateral TKA group. Data on patient demography, pain scores, and side effect scores were collected. Total dose consumption, demand, delivery doses, demand-to-delivery ratio, and infusion rate were collected from PCA machines and analyzed. RESULTS: The patient pain score and patient satisfaction showed no significant difference between the unilateral and bilateral TKA groups. The incidence of sedation (p < 0.001), nausea (p = 0.013), and vomiting (p = 0.044) during the postoperative 24-48-hour period was higher in the bilateral TKA group. Compared with the patients in the unilateral group, those in the bilateral group showed significantly greater dose consumption during the postoperative 6-12-, 12-18-, and 18-24-hour periods. They also showed more demand for medication during the postoperative 12-18- and 18-24-hour periods and received more bolus doses during the postoperative 12-18-, 18-24-, and 30-36-hour periods. In addition, there was also a significantly higher demand-to-delivery ratio for patients in the bilateral group during the postoperative 6-12-, 12-18-hour periods. CONCLUSION: In this study, we successfully demonstrated that our IVPCA protocol can provide adequate analgesia for patients after both bilateral and unilateral TKA. However, sedation, nausea, and vomiting occurred more frequently during the postoperative 24-48-hour period in patients who underwent bilateral than unilateral TKA. This may due of the increased number of bolus doses administered to the patients in the bilateral TKA group during the postoperative 12-18, 18-24, and 30-36-hour periods. Therefore, the initial infusion rates for patients undergoing bilateral TKA could be set at a lower threshold in order to reduce the incidence of these side effects.


Assuntos
Analgesia Controlada pelo Paciente , Artroplastia do Joelho/métodos , Idoso , Artroplastia do Joelho/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
13.
PLoS One ; 8(1): e55028, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23383045

RESUMO

Streptococcal pyrogenic exotoxin B (SPE B), a cysteine protease, is an important virulence factor in group A streptococcal (GAS) infection. SPE B binds and cleaves antibody isotypes and further impairs the immune system by inhibiting complement activation. In this study, we examined the antibody-binding site of SPE B and used it to block SPE B actions during GAS infection. We constructed different segments of the spe B gene and induced them to express different recombinant fragments of SPE B. Using an enzyme-linked immunosorbent assay (ELISA), we found that residues 345-398 of the C-terminal domain of SPE B (rSPE B(345-398)), but not the N-terminal domain, was the major binding site for antibody isotypes. Using a competitive ELISA, we also found that rSPE B(345-398) bound to the Fc portion of IgG. The in vitro functional assays indicate that rSPE B(345-398) not only interfered with cleavage of antibody isotypes but also interfered with SPE B-induced inhibition of complement activation. Immunization of BALB/c mice using rSPE B(345-398) was able to induce production of a high titer of anti-rSPE B(345-398) antibodies and efficiently protected mice from GAS-induced death. These findings suggest that SPE B uses its C-terminal domain to bind the Fc portion of IgG and that immunization of mice with this binding domain (rSPE B(345-398)) could protect mice from GAS infection.


Assuntos
Anticorpos Antibacterianos/imunologia , Proteínas de Bactérias/imunologia , Exotoxinas/imunologia , Infecções Estreptocócicas/prevenção & controle , Streptococcus pyogenes/fisiologia , Animais , Anticorpos Antibacterianos/sangue , Anticorpos Antibacterianos/química , Proteínas de Bactérias/química , Proteínas de Bactérias/farmacologia , Vacinas Bacterianas/química , Vacinas Bacterianas/imunologia , Vacinas Bacterianas/farmacologia , Sítios de Ligação , Ativação do Complemento/efeitos dos fármacos , Ativação do Complemento/imunologia , Exotoxinas/química , Exotoxinas/farmacologia , Humanos , Imunização , Fragmentos Fc das Imunoglobulinas/imunologia , Masculino , Camundongos , Estrutura Terciária de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/farmacologia , Streptococcus pyogenes/imunologia
14.
Nat Biotechnol ; 30(8): 777-82, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22820318

RESUMO

Genome-wide transcriptome analyses are routinely used to monitor tissue-, disease- and cell type­specific gene expression, but it has been technically challenging to generate expression profiles from single cells. Here we describe a robust mRNA-Seq protocol (Smart-Seq) that is applicable down to single cell levels. Compared with existing methods, Smart-Seq has improved read coverage across transcripts, which enhances detailed analyses of alternative transcript isoforms and identification of single-nucleotide polymorphisms. We determined the sensitivity and quantitative accuracy of Smart-Seq for single-cell transcriptomics by evaluating it on total RNA dilution series. We found that although gene expression estimates from single cells have increased noise, hundreds of differentially expressed genes could be identified using few cells per cell type. Applying Smart-Seq to circulating tumor cells from melanomas, we identified distinct gene expression patterns, including candidate biomarkers for melanoma circulating tumor cells. Our protocol will be useful for addressing fundamental biological problems requiring genome-wide transcriptome profiling in rare cells.


Assuntos
Perfilação da Expressão Gênica/métodos , Células Neoplásicas Circulantes/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos/métodos , RNA Mensageiro/química , Análise de Sequência de RNA/métodos , Animais , Análise por Conglomerados , Feminino , Biblioteca Gênica , Humanos , Melanoma/sangue , Melanoma/genética , Melanoma/metabolismo , Melanoma/patologia , Camundongos , Células Neoplásicas Circulantes/química , Células Neoplásicas Circulantes/patologia , RNA Mensageiro/genética , Sensibilidade e Especificidade
15.
PLoS One ; 6(8): e23018, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21857983

RESUMO

Human pluripotent stem cell (hPSC) lines have been considered to be homogeneously euploid. Here we report that normal hPSC--including induced pluripotent--lines are karyotypic mosaics of euploid cells intermixed with many cells showing non-clonal aneuploidies as identified by chromosome counting, spectral karyotyping (SKY) and fluorescent in situ hybridization (FISH) of interphase/non-mitotic cells. This mosaic aneuploidy resembles that observed in progenitor cells of the developing brain and preimplantation embryos, suggesting that it is a normal, rather than pathological, feature of stem cell lines. The karyotypic heterogeneity generated by mosaic aneuploidy may contribute to the reported functional and phenotypic heterogeneity of hPSCs lines, as well as their therapeutic efficacy and safety following transplantation.


Assuntos
Aneuploidia , Células-Tronco Pluripotentes/citologia , Células-Tronco Pluripotentes/metabolismo , Animais , Técnicas de Cultura de Células , Linhagem Celular , Feminino , Humanos , Hibridização in Situ Fluorescente , Cariotipagem , Camundongos , Cariotipagem Espectral
16.
Cancer Res ; 68(10): 3999-4009, 2008 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-18483287

RESUMO

Histone deacetylase (HDAC) inhibitors suppress tumor cell growth via a broad spectrum of mechanisms, which should prove advantageous in the context of cancer prevention. Here, we examined the effect of dietary administration of OSU-HDAC42, a novel HDAC inhibitor, on prostate tumor progression in the transgenic adenocarcinoma of the mouse prostate (TRAMP) model. Based on a series of pilot studies, an AIN-76A diet was formulated containing 208 ppm OSU-HDAC42, which was estimated to deliver approximately 25 mg/kg of drug per day to each mouse and found to cause a suppression of PC-3 xenograft tumor growth equivalent to that achieved by gavage administration of a similar dose. At 6 weeks of age, TRAMP mice received this drug-containing or control diet for 4 or 18 weeks and were evaluated for prostatic intraepithelial neoplasia (PIN) and carcinoma development, respectively. OSU-HDAC42 not only decreased the severity of PIN and completely prevented its progression to poorly differentiated carcinoma (74% incidence in controls versus none in drug-treated mice), but also shifted tumorigenesis to a more differentiated phenotype, suppressing absolute and relative urogenital tract weights by 86% and 85%, respectively, at 24 weeks of age. This tumor suppression was associated with the modulation of intraprostatic biomarkers, including those indicative of HDAC inhibition, increased apoptosis and differentiation, and decreased proliferation. With the exception of completely reversible hematologic alterations and testicular degeneration, no significant changes in body weight or other indicators of general health were observed in drug-treated mice. These results suggest that OSU-HDAC42 has value in prostate cancer prevention. [Cancer Res 2008;68(10):3999-4009].


Assuntos
Adenocarcinoma/tratamento farmacológico , Inibidores Enzimáticos/farmacologia , Inibidores de Histona Desacetilases , Fenilbutiratos/farmacologia , Neoplasias da Próstata/tratamento farmacológico , Adenocarcinoma/enzimologia , Adenocarcinoma/genética , Administração Oral , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Humanos , Ácidos Hidroxâmicos/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Transplante de Neoplasias , Neoplasias da Próstata/enzimologia , Neoplasias da Próstata/genética , Vorinostat
17.
Cancer Res ; 68(8): 2820-30, 2008 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-18413750

RESUMO

Preexisting and acquired resistance to epidermal growth factor receptor (EGFR) inhibitors limits their clinical usefulness in patients with advanced non-small cell lung cancer (NSCLC). This study characterizes the efficacy and mechanisms of the combination of gefitinib or erlotinib with OSU-03012, a celecoxib-derived antitumor agent, to overcome EGFR inhibitor resistance in three NSCLC cell lines, H1155, H23, and A549. The OSU-03012/EGFR inhibitor combination induced pronounced apoptosis in H1155 and H23 cells, but not in A549 cells, suggesting a correlation between drug sensitivity and basal phospho-Akt levels independently of EGFR expression status. Evidence indicates that this combination facilitates apoptosis through both Akt signaling inhibition and up-regulation of endoplasmic reticulum (ER) stress-induced, GADD153-mediated pathways. For example, ectopic expression of constitutively active Akt significantly attenuated the inhibitory effect on cell survival, and small interfering RNA-mediated knockdown of GADD153 protected cells from undergoing apoptosis in response to drug cotreatments. Furthermore, the OSU-03012/EGFR inhibitor combination induced GADD153-mediated up-regulation of death receptor 5 expression and subsequent activation of the extrinsic apoptosis pathway. It is noteworthy that the ER stress response induced by this combination was atypical in that the cytoprotective pathway was not engaged. In addition, in vivo suppression of tumor growth and modulation of intratumoral biomarkers were observed in a H1155 tumor xenograft model in nude mice. These data suggest that the concomitant modulation of Akt and ER stress pathways with the OSU-03012/EGFR inhibitor combination represents a unique approach to overcoming EGFR inhibitor resistance in NSCLC and perhaps other types of cancer with elevated basal Akt activities.


Assuntos
Retículo Endoplasmático/fisiologia , Receptores ErbB/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/metabolismo , Pirazóis/farmacologia , Quinazolinas/farmacologia , Sulfonamidas/farmacologia , Actinas/genética , Antineoplásicos/farmacologia , Carcinoma Pulmonar de Células não Pequenas , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Retículo Endoplasmático/efeitos dos fármacos , Cloridrato de Erlotinib , Citometria de Fluxo , Gefitinibe , Humanos , Neoplasias Pulmonares , Proteínas Proto-Oncogênicas c-akt/efeitos dos fármacos , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
18.
J Med Chem ; 51(7): 2100-7, 2008 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-18335975

RESUMO

On the basis of our finding that the peroxisome proliferator-activated receptor gamma (PPARgamma) agonist ciglitazone at high doses was able to mediate PPARgamma-independent transcriptional repression of androgen receptor (AR) in a tumor cell-specific manner, we used Delta2CG, a PPARgamma-inactive analogue of ciglitazone, to conduct lead optimization to develop a novel class of AR-ablative agents. Structure-activity analysis indicates a high degree of flexibility in realigning Delta2CG's structural moieties without compromising potency in AR repression, as evidenced by the higher AR-ablative activity of the permuted isomer 9 [( Z)-5-(4-hydroxybenzylidene)-3-(1-methylcyclohexylmethyl)thiazolidine-2,4-dione]. Further modifications of 9 gave rise to 12 [( Z)-5-(4-hydroxy-3-trifluoromethylbenzylidene)-3-(1-methylcyclohexylmethyl)thiazolidine-2,4-dione], which completely inhibited AR expression in LNCaP cells at low micromolar concentrations. This AR down-regulation led to growth inhibition in LNCaP cells through apoptosis induction. Moreover, the role of AR repression in the antiproliferative effect of compound 12 was validated by the differential inhibition of cell viability between androgen-responsive and androgen-nonresponsive cells.


Assuntos
Antagonistas de Receptores de Andrógenos , Antineoplásicos/síntese química , Antineoplásicos/farmacologia , PPAR gama/agonistas , Tiazolidinedionas/farmacologia , Antineoplásicos/classificação , Contagem de Células , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/genética , Receptores Androgênicos/genética , Relação Estrutura-Atividade , Tiazolidinedionas/síntese química , Tiazolidinedionas/química
19.
Cancer Res ; 68(4): 1204-12, 2008 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-18281497

RESUMO

This study was aimed at elucidating the mechanism by which FTY720, a synthetic sphingosine immunosuppressant, mediated antitumor effects in hepatocellular carcinoma (HCC) cells. The three HCC cell lines examined, Hep3B, Huh7, and PLC5, exhibited differential susceptibility to FTY720-mediated suppression of cell viability, with IC(50) values of 4.5, 6.3, and 11 mumol/L, respectively. Although FTY720 altered the phosphorylation state of protein kinase B and p38, our data refuted the role of these two signaling kinases in FTY720-mediated apoptosis. Evidence indicates that the antitumor effect of FTY720 was attributable to its ability to stimulate reactive oxygen species (ROS) production, which culminated in protein kinase C (PKC)delta activation and subsequent caspase-3-dependent apoptosis. We showed that FTY720 activated PKC delta through two distinct mechanisms: phosphorylation and caspase-3-dependent cleavage. Cotreatment with the caspase-3 inhibitor Z-VAD-FMK abrogated the effect of FTY720 on facilitating PKC delta proteolysis. Equally important, pharmacologic inhibition or shRNA-mediated knockdown of PKC delta protected FTY720-treated Huh7 cells from caspase-3 activation. Moreover, FTY720 induced ROS production to different extents among the three cell lines, in the order of Hep3B > Huh7 >> PLC5, which inversely correlated with the respective glutathione S-transferase pi expression levels. The low level of ROS generation might underlie the resistant phenotype of PLC5 cells to the apoptotic effects of FTY720. Blockade of ROS production by an NADPH oxidase inhibitor protected Huh7 cells from FTY720-induced PKC delta activation and caspase-3-dependent apoptosis. Together, this study provides a rationale to use FTY720 as a scaffold to develop potent PKC delta-activating agents for HCC therapy.


Assuntos
Apoptose/efeitos dos fármacos , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Propilenoglicóis/farmacologia , Proteína Quinase C-delta/metabolismo , Esfingosina/análogos & derivados , Carcinoma Hepatocelular/enzimologia , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Ativação Enzimática/efeitos dos fármacos , Cloridrato de Fingolimode , Humanos , Neoplasias Hepáticas/enzimologia , Neoplasias Hepáticas/patologia , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Esfingosina/farmacologia
20.
Cancer Detect Prev ; 31(5): 366-70, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18035504

RESUMO

BACKGROUND: Clinical and experimental studies suggest that alteration of the expression level of the p53 gene and other damage responsive genes may be associated with chemoresistance in cancer patients. METHODS: The present study evaluated the differences of the basal levels of lymphocytic p53 and p21waf1 mRNA expression collected before receiving cisplatin-based chemotherapy between 48 chemo-ineffective lung cancer patients and 39 chemo-effective lung cancer patients using an optimized semi-quantitative multiplex reverse transcriptase-polymerase chain reaction (RT-PCR). RESULTS: The data indicated that the mean mRNA level of p53 gene in chemo-ineffective patients (0.66) was 26.9% higher than that of the chemo-effective patients (0.52) with statistical significance (P=0.03), and a significantly higher level of p21waf1 mRNA expression in the chemo-ineffective patients (P=0.03) was also observed. In addition, by the multiplex long quantitative PCR analysis, we demonstrated that chemo-ineffective and chemo-effective patients have similar amounts of UV damage on their p53 gene of lymphocyte DNA through equal UV treatment. CONCLUSION: Our results suggest that elevated levels of p53/p21waf1 mRNA in blood lymphocytes collected before chemotherapy may predict the chemoresponses of lung cancer patients.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/biossíntese , Resistencia a Medicamentos Antineoplásicos/genética , Neoplasias Pulmonares/metabolismo , Linfócitos/metabolismo , Proteína Supressora de Tumor p53/biossíntese , Antineoplásicos/uso terapêutico , Biomarcadores Tumorais/análise , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Cisplatino/uso terapêutico , Genes p53/genética , Genes p53/efeitos da radiação , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , RNA Mensageiro , Reação em Cadeia da Polimerase Via Transcriptase Reversa
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