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1.
Oecologia ; 200(3-4): 285-294, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35962285

RESUMO

Male and female reproductive behaviour is typically synchronised. In species such as those in the family Cervidae, reproductive timing is often cued by photoperiod, although in females, it can be dependent on body condition. When a species is introduced to a novel environment, the environment changes, or responses of the sexes to such cues differ, asynchronous reproductive behaviour between males and females may occur. We investigated the seasonality of reproductive behaviour in introduced chital deer in northern Queensland by examining male antler phase in relation to female conception rates. We then analysed the influence of different variables likely to affect the timing of male and female reproductive physiology. The lowest percentage of chital in hard antler in any 1 month in this study was 35% (Fig. 1), but the average value was closer to 50%, thus there was a seasonal peak in antler phase linked with photoperiod. Females conceived at any time of year, but were strongly influenced by the amount of rainfall 3 months prior to conception. This resulted in varying conception peaks year-to-year that often did not correspond to the male's peak in hard antler. In this system, a proportion of males and females were physiologically and behaviourally ready to mate at any time of the year. We predict that differences in the timing of the peaks between the males and females will lead to increased reproductive skew (variation in reproductive success among individual males). This pattern may select for different mating strategies or physiological mechanisms to increase reproductive success. Fig. 1 The average percentage of male chital deer in hard antler by month from 2014 to 2019 in north Queensland. Values above the bars indicate the total number of males that were sampled in each month and the error bars indicate the standard error. In the month with the lowest % males in hard antler in the entire study (November, 2017), 35% of males were in hard antler.


Assuntos
Cervos , Animais , Feminino , Masculino , Reprodução , Fertilização , Sinais (Psicologia)
2.
Sci Data ; 7(1): 27, 2020 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-31964871

RESUMO

A gene expression-based siRNA screen was used to evaluate functional similarity between genetic perturbations to identify functionally similar proteins. A siRNA library (siGenome library, Dharmacon) consisting of multiple siRNAs per gene that have been pooled in to one well per gene was arrayed in a 384-well format and used to individually target 14,335 proteins for depletion in HCT116 colon cancer cells. For each protein depletion, the gene expression of eight genes was quantified using the multiplexed Affymetrix Quantigene 2.0 assay in technical triplicate. As a proof of concept, six genes (BNIP3, NDRG1, ALDOC, LOXL2, ACSL5, BNIP3L) whose expression pattern reliably reflect the disruption of the molecular scaffold KSR1 were measured upon each protein depletion. The remaining two genes (PPIB and HPRT) are housekeeping genes used for normalization. The gene expression signatures from this screen can be used to estimate the functional similarity between any two proteins and successfully identified functional relationships for specific proteins such as KSR1 and more generalized processes, such as autophagy.


Assuntos
Perfilação da Expressão Gênica , Biblioteca Gênica , Genes Neoplásicos , RNA Interferente Pequeno , Células HCT116 , Sequenciamento de Nucleotídeos em Larga Escala , Humanos
3.
PLoS One ; 14(3): e0214078, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30917169

RESUMO

BACKGROUND: Long term dietary consumption of genistein by Chinese men is associated with decreased PCa metastasis and mortality. Short term treatment of US men with prostate cancer (PCa) with genistein decreases MMP-2 in prostate tissue. MEK4 regulates MMP-2 expression, drives PCa metastasis, and genistein inhibits MEK4, decreases MMP-2 expression and dietary dosing inhibits human PCa metastasis in mice. This study examines short- versus long-term treatment effects of genistein in humans and in vitro. METHODS AND FINDINGS: US men with localized PCa were treated on a phase II trial with genistein (N = 14) versus not (N = 14) for one month prior to radical prostatectomy. Prostate epithelial cells were removed from fresh frozen tissue by laser capture microdissection, and the expression of 12,000 genes profiled. Genistein significantly altered the expression of four genes, three had established links to cancer cell motility and metastasis. Of these three, one was a non-coding transcript, and the other two were BASP1 and HCF2. Genistein increased BASP1 expression in humans, and its engineered over expression and knockdown demonstrated that it suppressed cell invasion in all six human prostate cell lines examined. Genistein decreased HCF2 expression in humans, and it was shown to increase cell invasion in all cell lines examined. The expression of MMP-2, MEK4 and BASP1 was then measured in formalin fixed prostate tissue from N = 38 Chinese men living in China and N = 41 US men living in the US, both cohorts with localized PCa. MMP-2 was 52% higher in Chinese compared to US tissue (P < 0.0001), MEK4 was 48% lower (P < 0.0001), and BASP1 was unaltered. Treatment of PC3 human PCa cells in vitro for up to 8 weeks demonstrated that short term genistein treatment decreased MMP-2, while long term treatment increased it, both changes being significant (P<0.05) compared to untreated control cells. Long term genistein-treated cells retained their responsiveness to genistein's anti-motility effect. CONCLUSIONS: Genistein inhibits pathways in human prostate that drive transformation to a lethal high motility phenotype. Long term treatment induces compensatory changes in biomarkers of efficacy. The current strategy of using such biomarkers after short term intervention as go/no-go determinants in early phase chemoprevention trials should be carefully examined.


Assuntos
Biomarcadores Tumorais/metabolismo , Movimento Celular/efeitos dos fármacos , Genisteína/administração & dosagem , Proteínas de Neoplasias/metabolismo , Próstata , Neoplasias da Próstata , Animais , Humanos , Masculino , Camundongos , Metástase Neoplásica , Células PC-3 , Próstata/metabolismo , Próstata/patologia , Prostatectomia , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia
4.
Anal Biochem ; 569: 46-52, 2019 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-30707898

RESUMO

Due to the therapeutic potential of targeting protein-protein interactions (PPIs) there is a need for easily executed assays to perform high throughput screening (HTS) of inhibitors. We have developed and optimized an innovative and robust fluorescence-based assay for detecting PPI inhibitors, called FluorIA (Fluorescence-based protein-protein Interaction Assay). Targeting the PPI of RAD52 with replication protein A (RPA) was used as an example, and the FluorIA protocol design, optimization and successful application to HTS of large chemical libraries are described. Here enhanced green fluorescent protein (EGFP)-tagged RAD52 detected the PPI using full-length RPA heterotrimer coated, black microtiter plates and loss in fluorescence intensity identified small molecule inhibitors (SMIs) that displaced the EGFP-tagged RAD52. The FluorIA design and protocol can be adapted and applied to detect PPIs for other protein systems. This should push forward efforts to develop targeted therapeutics against protein complexes in pathological processes.


Assuntos
Proteínas de Fluorescência Verde/metabolismo , Mapas de Interação de Proteínas , Proteína Rad52 de Recombinação e Reparo de DNA/metabolismo , Bibliotecas de Moléculas Pequenas/química , Espectrometria de Fluorescência/métodos , Proteínas de Fluorescência Verde/química , Ensaios de Triagem em Larga Escala , Humanos , Concentração de Íons de Hidrogênio , Ligação Proteica , Proteína Rad52 de Recombinação e Reparo de DNA/química , Bibliotecas de Moléculas Pequenas/metabolismo
5.
Sci Rep ; 8(1): 3770, 2018 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-29491475

RESUMO

AMPK is a serine threonine kinase composed of a heterotrimer of a catalytic, kinase-containing α and regulatory ß and γ subunits. Here we show that individual AMPK subunit expression and requirement for survival varies across colon cancer cell lines. While AMPKα1 expression is relatively consistent across colon cancer cell lines, AMPKα1 depletion does not induce cell death. Conversely, AMPKα2 is expressed at variable levels in colon cancer cells. In high expressing SW480 and moderate expressing HCT116 colon cancer cells, siRNA-mediated depletion induces cell death. These data suggest that AMPK kinase inhibition may be a useful component of future therapeutic strategies. We used Functional Signature Ontology (FUSION) to screen a natural product library to identify compounds that were inhibitors of AMPK to test its potential for detecting small molecules with preferential toxicity toward human colon tumor cells. FUSION identified 5'-hydroxy-staurosporine, which competitively inhibits AMPK. Human colon cancer cell lines are notably more sensitive to 5'-hydroxy-staurosporine than are non-transformed human colon epithelial cells. This study serves as proof-of-concept for unbiased FUSION-based detection of small molecule inhibitors of therapeutic targets and highlights its potential to identify novel compounds for cancer therapy development.


Assuntos
Proteínas Quinases Ativadas por AMP/antagonistas & inibidores , Ontologias Biológicas , Neoplasias do Colo/patologia , Inibidores de Proteínas Quinases/farmacologia , Produtos Biológicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos
6.
J Neurooncol ; 132(1): 35-44, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28102487

RESUMO

There is little data on why glioblastomas (GBM) hemorrhage and how it may affect patient outcomes. The aim of this study was to investigate the mechanisms of hemorrhage in glioblastoma by examining molecular and genetic features by immunohistochemistry (IHC) and mRNA expression profiles in association with imaging and clinical outcomes. An observational retrospective cohort analysis was performed on 43 FFPE GBM tissue samples. MR images were assessed for the presence of hemorrhage and extent of resection. Specimens were examined for CD34 and CD105 expression using IHC. Tumor mRNA expression profiles were analyzed for 92 genes related to angiogenesis and vascularity. Forty-three specimens were analyzed, and 20 showed signs of hemorrhage, 23 did not. The average OS for patients with GBM with hemorrhage was 19.12 months (95% CI 10.39-27.84), versus 13.85 months (95% CI 8.85-18.85) in those without hemorrhage (p > 0.05). Tumors that hemorrhaged had higher IHC staining for CD34 and CD105. mRNA expression analysis revealed tumor hemorrhage was associated with increased expression of HIF1α and MDK, and decreased expression of F3. Hemorrhage in GBM was not associated with worsened OS. Increased expression of angiogenic factors and increased CD34 and CD105 IHC staining in tumors with hemorrhage suggests that increased hypoxia-induced angiogenesis and vessel density may play a role in glioblastoma hemorrhage. Characterizing tumors that are prone to hemorrhage and mechanisms behind the development of these hemorrhages may provide insights that can lead to the development of targeted, individualized therapies for glioblastoma.


Assuntos
Neoplasias Encefálicas/irrigação sanguínea , Neoplasias Encefálicas/metabolismo , Glioblastoma/irrigação sanguínea , Glioblastoma/metabolismo , Neovascularização Patológica/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos CD34/metabolismo , Neoplasias Encefálicas/diagnóstico , Endoglina/metabolismo , Feminino , Glioblastoma/diagnóstico , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/metabolismo , Estudos Retrospectivos
7.
J Pharm Pract ; 30(1): 75-81, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26677861

RESUMO

BACKGROUND: In 2012, pharmacists were integrated into a medical group to provide direct patient care, drug information activities, and health care provider education. The medical group encompasses 40 primary care and 60 specialty offices in Virginia. OBJECTIVE: To describe the development and implementation of clinical pharmacist services integrated within a medical group. METHODS: Pharmacists' roles and responsibilities, type and number of patient encounters, and identification of strategies to facilitate implementation are described. RESULTS: From June 2012 to December 2014, pharmacists had 809 patient encounters, which included patient-centered education, medication consults, Medicare annual wellness visits, senior care visits, and comprehensive medication reviews. Pharmacists addressed 403 drug information requests from nurse navigators, providers, and administrators. Pharmacists also have roles in risk management, quality improvement initiatives, and operations that benefit the medical group. Strategies to facilitate implementation include working with organizational leadership, identifying a physician champion, and establishing credibility by being responsive to practice needs and responding to requests in a timely manner to build trust within the health care team. CONCLUSION: Integration of pharmacists within health care teams involves more than direct patient care activities. Pharmacists should be involved at the organizational level to have a broader impact on patient and practice levels.


Assuntos
Equipe de Assistência ao Paciente/organização & administração , Serviço de Farmácia Hospitalar/organização & administração , Humanos , Farmacêuticos , Serviço de Farmácia Hospitalar/estatística & dados numéricos , Papel Profissional , Desenvolvimento de Programas
9.
Mol Cell Biol ; 36(17): 2246-61, 2016 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-27273865

RESUMO

Identification and characterization of survival pathways active in tumor cells but absent in normal tissues provide opportunities to develop effective anticancer therapies with reduced toxicity to the patient. We show here that, like kinase suppressor of Ras 1 (KSR1), EPH (erythropoietin-producing hepatocellular carcinoma) receptor B4 (EPHB4) is aberrantly overexpressed in human colon tumor cell lines and selectively required for their survival. KSR1 and EPHB4 support tumor cell survival by promoting the expression of downstream targets, Myc and the transcriptional coactivator peroxisome proliferator-activated receptor gamma coactivator 1ß (PGC1ß). While KSR1 promotes the aberrant expression of Myc and the PGC1ß protein via a posttranscriptional mechanism, EPHB4 has a greater effect on Myc and PGC1ß expression via its ability to elevate mRNA levels. Subsequent analysis of the posttranscriptional regulation demonstrated that KSR1 promotes the translation of Myc protein. These findings reveal novel KSR1- and EPHB4-dependent signaling pathways supporting the survival of colorectal cancer cells through regulation of Myc and PGC1ß, suggesting that inhibition of KSR1 or EPHB4 effectors may lead to selective toxicity in colorectal tumors.


Assuntos
Proteínas de Transporte/genética , Neoplasias do Colo/metabolismo , Proteínas Quinases/metabolismo , Proteínas Proto-Oncogênicas c-myc/genética , Receptor EphB4/metabolismo , Células CACO-2 , Linhagem Celular Tumoral , Sobrevivência Celular , Regulação Neoplásica da Expressão Gênica , Células HCT116 , Humanos , Processamento Pós-Transcricional do RNA , Proteínas de Ligação a RNA , Regulação para Cima
10.
Mol Cell Biol ; 35(22): 3866-79, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26351140

RESUMO

A major goal of cancer research is the identification of tumor-specific vulnerabilities that can be exploited for the development of therapies that are selectively toxic to the tumor. We show here that the transcriptional coactivators peroxisome proliferator-activated receptor gamma coactivator 1ß (PGC1ß) and estrogen-related receptor α (ERRα) are aberrantly expressed in human colon cell lines and tumors. With kinase suppressor of Ras 1 (KSR1) depletion as a reference standard, we used functional signature ontology (FUSION) analysis to identify the γ1 subunit of AMP-activated protein kinase (AMPK) as an essential contributor to PGC1ß expression and colon tumor cell survival. Subsequent analysis revealed that a subunit composition of AMPK (α2ß2γ1) is preferred for colorectal cancer cell survival, at least in part, by stabilizing the tumor-specific expression of PGC1ß. In contrast, PGC1ß and ERRα are not detectable in nontransformed human colon epithelial cells, and depletion of the AMPKγ1 subunit has no effect on their viability. These data indicate that Ras oncogenesis relies on the aberrant activation of a PGC1ß-dependent transcriptional pathway via a specific AMPK isoform.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Proteínas de Transporte/genética , Colo/patologia , Neoplasias do Colo/genética , Regulação Neoplásica da Expressão Gênica , Animais , Proteínas de Transporte/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular , Colo/metabolismo , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Proteínas Quinases/genética , Proteínas Quinases/metabolismo , Subunidades Proteicas/metabolismo , Proteínas de Ligação a RNA , Receptores de Estrogênio/genética , Receptores de Estrogênio/metabolismo , Receptor ERRalfa Relacionado ao Estrogênio
11.
J Biol Chem ; 289(44): 30443-30458, 2014 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-25225290

RESUMO

ErbB2 overexpression drives oncogenesis in 20-30% cases of breast cancer. Oncogenic potential of ErbB2 is linked to inefficient endocytic traffic into lysosomes and preferential recycling. However, regulation of ErbB2 recycling is incompletely understood. We used a high-content immunofluorescence imaging-based kinase inhibitor screen on SKBR-3 breast cancer cells to identify kinases whose inhibition alters the clearance of cell surface ErbB2 induced by Hsp90 inhibitor 17-AAG. Less ErbB2 clearance was observed with broad-spectrum PKC inhibitor Ro 31-8220. A similar effect was observed with Go 6976, a selective inhibitor of classical Ca(2+)-dependent PKCs (α, ß1, ßII, and γ). PKC activation by PMA promoted surface ErbB2 clearance but without degradation, and ErbB2 was observed to move into a juxtanuclear compartment where it colocalized with PKC-α and PKC-δ together with the endocytic recycling regulator Arf6. PKC-α knockdown impaired the juxtanuclear localization of ErbB2. ErbB2 transit to the recycling compartment was also impaired upon PKC-δ knockdown. PMA-induced Erk phosphorylation was reduced by ErbB2 inhibitor lapatinib, as well as by knockdown of PKC-δ but not that of PKC-α. Our results suggest that activation of PKC-α and -δ mediates a novel positive feedback loop by promoting ErbB2 entry into the endocytic recycling compartment, consistent with reported positive roles for these PKCs in ErbB2-mediated tumorigenesis. As the endocytic recycling compartment/pericentrion has emerged as a PKC-dependent signaling hub for G-protein-coupled receptors, our findings raise the possibility that oncogenesis by ErbB2 involves previously unexplored PKC-dependent endosomal signaling.


Assuntos
Antineoplásicos/farmacologia , Proteína Quinase C-alfa/metabolismo , Proteína Quinase C-delta/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Receptor ErbB-2/metabolismo , Benzoquinonas/farmacologia , Neoplasias da Mama , Carbazóis/farmacologia , Carcinogênese/metabolismo , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Endocitose/efeitos dos fármacos , Endossomos/metabolismo , Ativação Enzimática , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Retroalimentação Fisiológica , Feminino , Humanos , Indóis/farmacologia , Lactamas Macrocíclicas/farmacologia , Sistema de Sinalização das MAP Quinases , Fosforilação , Proteína Quinase C-alfa/antagonistas & inibidores , Proteína Quinase C-delta/antagonistas & inibidores , Processamento de Proteína Pós-Traducional , Transporte Proteico
13.
Proc Natl Acad Sci U S A ; 108(47): 19036-41, 2011 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-22065774

RESUMO

Negative-strand (NS) RNA viruses comprise many pathogens that cause serious diseases in humans and animals. Despite their clinical importance, little is known about the host factors required for their infection. Using vesicular stomatitis virus (VSV), a prototypic NS RNA virus in the family Rhabdoviridae, we conducted a human genome-wide siRNA screen and identified 72 host genes required for viral infection. Many of these identified genes were also required for infection by two other NS RNA viruses, the lymphocytic choriomeningitis virus of the Arenaviridae family and human parainfluenza virus type 3 of the Paramyxoviridae family. Genes affecting different stages of VSV infection, such as entry/uncoating, gene expression, and assembly/release, were identified. Depletion of the proteins of the coatomer complex I or its upstream effectors ARF1 or GBF1 led to detection of reduced levels of VSV RNA. Coatomer complex I was also required for infection of lymphocytic choriomeningitis virus and human parainfluenza virus type 3. These results highlight the evolutionarily conserved requirements for gene expression of diverse families of NS RNA viruses and demonstrate the involvement of host cell secretory pathway in the process.


Assuntos
Fatores Celulares Derivados do Hospedeiro/genética , Via Secretória/genética , Vírus da Estomatite Vesicular Indiana/fisiologia , Integração Viral/genética , Animais , Linhagem Celular , Cães , Eletroforese em Gel de Poliacrilamida , Perfilação da Expressão Gênica , Humanos , Immunoblotting , Vírus da Coriomeningite Linfocítica/genética , Vírus da Coriomeningite Linfocítica/fisiologia , Vírus da Parainfluenza 3 Humana/genética , Vírus da Parainfluenza 3 Humana/fisiologia , Interferência de RNA , RNA Interferente Pequeno/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Vírus da Estomatite Vesicular Indiana/genética
14.
Bioorg Med Chem Lett ; 21(7): 1929-32, 2011 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-21376584

RESUMO

The quinoxaline core is considered a privileged scaffold as it is found in a variety of biologically relevant molecules. Here we report the synthesis of a quinoxalin-6-amine library, screening against a panel of cancer cell lines and a structure-activity relationship (SAR). This resulted in the identification of a bisfuranylquinoxalineurea analog (7c) that has low micromolar potency against the panel of cancer cell lines. We also show that cells treated with quinoxalineurea 7c results in caspase 3/7 activation, PARP cleavage and Mcl-1 dependent apoptosis.


Assuntos
Quinoxalinas/química , Quinoxalinas/farmacologia , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Relação Estrutura-Atividade
15.
Int J Cancer ; 125(4): 816-25, 2009 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-19382180

RESUMO

Epithelial ovarian carcinoma (EOC) is a leading cause of death from gynecologic malignancies, due mainly to the prevalence of undetected metastatic disease. The process of cell invasion during intraperitoneal anchoring of metastatic lesions requires concerted regulation of many processes, including modulation of adhesion to the extracellular matrix and localized invasion. Exploratory cDNA microarray analysis of early response genes (altered after 4 hr of 3D collagen culture) coupled with confirmatory real-time reverse-transcriptase polymerase chain reaction, multiple 3D cell culture matrices, Western blot, immunostaining, adhesion, migration and invasion assays were used to identify modulators of adhesion pertinent to EOC progression and metastasis. cDNA microarray analysis indicated a dramatic downregulation of connective tissue growth factor (CTGF) in EOC cells placed in invasion- mimicking conditions (3D Type I collagen). Examination of human EOC specimens revealed that CTGF expression was absent in 46% of the tested samples (n = 41), but was present in 100% of normal ovarian epithelium samples (n = 7). Reduced CTGF expression occurs in many types of cells and may be a general phenomenon displayed by cells encountering a 3D environment. CTGF levels were inversely correlated with invasion such that downregulation of CTGF increased, while its upregulation reduced collagen invasion. Cells adhered preferentially to a surface comprised of both collagen I and CTGF relative to either component alone using alpha6beta1 and alpha3beta1 integrins. Together these data suggest that downregulation of CTGF in EOC cells may be important for cell invasion through modulation of cell-matrix adhesion.


Assuntos
Colágeno Tipo I/metabolismo , Fator de Crescimento do Tecido Conjuntivo/metabolismo , Neoplasias Ovarianas/patologia , Animais , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Western Blotting , Adesão Celular , Técnicas de Cultura de Células , Células Cultivadas , Fator de Crescimento do Tecido Conjuntivo/antagonistas & inibidores , Fator de Crescimento do Tecido Conjuntivo/genética , Regulação para Baixo , Endotélio Vascular/citologia , Endotélio Vascular/metabolismo , Feminino , Perfilação da Expressão Gênica , Humanos , Técnicas Imunoenzimáticas , Integrinas/metabolismo , Invasividade Neoplásica , Neurônios/citologia , Neurônios/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Neoplasias Ovarianas/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/farmacologia , Ratos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Esferoides Celulares , Veias Umbilicais/citologia , Veias Umbilicais/metabolismo
16.
J Control Release ; 131(3): 220-7, 2008 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-18722489

RESUMO

Doxorubicin (Dox) incorporated in nanosized polymeric micelles, SP1049C, has shown promise as monotherapy in patients with advanced esophageal carcinoma. The formulation contains amphiphilic block copolymers, Pluronics, that exhibit the unique ability to chemosensitize multidrug resistant (MDR) tumors by inhibiting P-glycoprotein (Pgp) drug efflux system and enhancing pro-apoptotic signaling in cancer cells. This work evaluates whether a representative block copolymer, Pluronic P85 (P85) can also prevent development of Dox-induced MDR in leukemia cells. For in vitro studies murine lymphocytic leukemia cells (P388) were exposed to increasing concentrations of Dox with/without P85. For in vivo studies, BDF1 mice bearing P388 ascite were treated with Dox or Dox/P85. The selected P388 cell sublines and ascitic tumor-derived cells were characterized for Pgp expression and functional activity (RT-PCR, Western Blot, rhodamine 123 accumulation) as well as Dox resistance (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay). The global gene expression was determined by oligonucleotide gene microarrays. We demonstrated that P85 prevented development of MDR1 phenotype in leukemia cells in vitro and in vivo as determined by Pgp expression and functional assays of the selected cells. Cells selected with Dox in the presence of P85 in vitro and in vivo exhibited some increases in IC(50) values compared to parental cells, but these values were much less than IC(50) in respective cells selected with the drug alone. In addition to mdr1, P85 abolished alterations of genes implicated in apoptosis, drug metabolism, stress response, molecular transport and tumorigenesis. In conclusion, Pluronic formulation can prevent development of MDR in leukemia cells in vitro and in vivo.


Assuntos
Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Micelas , Poloxaleno/farmacologia , Tensoativos/farmacologia , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/antagonistas & inibidores , Animais , Antibióticos Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Doxorrubicina/farmacologia , Feminino , Corantes Fluorescentes/metabolismo , Genes MDR , Concentração Inibidora 50 , Leucemia P388 , Camundongos , Camundongos Endogâmicos , Rodamina 123/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
17.
Biochim Biophys Acta ; 1779(5): 341-6, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18397763

RESUMO

Hepatocyte nuclear factor 1alpha (HNF1alpha) is a homeodomain transcription factor that is central to co-ordinated differentiation of a number of cell lineages, including hepatocytes in the liver and islet cells in the pancreas. HNF1alpha interacts directly with other transcription factors and co-factors and is involved in chromatin modification to alter gene expression. To further investigate the pivotal role of HNF1alpha in transcriptional control pathways we utilized RNA interference. An siRNA oligonucleotide specific for HNF1alpha reduced HNF1alpha protein levels by up to 70% in transient transfections of Caco2 cells. The same sequence incorporated into an shRNAi reduced protein levels by up to 90% in stable transfections. Microarray analysis of RNA from cell lines with stable RNAi-mediated down-regulation of HNF1alpha, identified genes known to be regulated by this transcription factor and also novel genes.


Assuntos
Regulação da Expressão Gênica , Fator 1-alfa Nuclear de Hepatócito/antagonistas & inibidores , Interferência de RNA , Células CACO-2 , Fator 1-alfa Nuclear de Hepatócito/genética , Humanos , Oligonucleotídeos/química , RNA Interferente Pequeno/química
18.
Lab Invest ; 88(6): 602-14, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18362906

RESUMO

Advanced and metastatic ovarian cancer is a leading cause of death from gynecologic malignancies. A more detailed understanding of the factors controlling invasion and metastasis may lead to novel anti-metastatic therapies. To model cellular interactions that occur during intraperitoneal metastasis, comparative cDNA microarray analysis and confirmatory real-time reverse transcription PCR (RT-PCR) were employed to uncover changes in gene expression that may occur in late stage ovarian cancer in response to microenvironmental cues, particularly native three-dimensional collagen I. Gene expression in human ovarian carcinoma tissues was evaluated on the RNA and protein level using real-time RT-PCR and immunohistochemistry. Cell invasion and migration were evaluated in a collagen invasion assay and a scratch wound assay. Three-dimensional collagen I culture led to differential expression of several genes. The role of actinin alpha-4 (ACTN4), a cytoskeleton-associated protein implicated in the regulation of cell motility, was examined in detail. ACTN4 RNA and protein expression were associated with advanced and metastatic human ovarian carcinoma. This report demonstrates that a cytoskeletal-associated protein ACTN4 is upregulated by three-dimensional collagen culture conditions, leading to increased invasion and motility of ovarian cancer cells. Expression of ACTN4 in human ovarian tumors was found to be associated with advanced-stage disease and peritoneal metastases.


Assuntos
Actinina/metabolismo , Carcinoma/patologia , Movimento Celular , Proteínas dos Microfilamentos/metabolismo , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Carcinoma/metabolismo , Linhagem Celular Tumoral , Colágeno Tipo I/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Metástase Neoplásica , Proteínas de Neoplasias/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Técnicas de Cultura de Órgãos , Neoplasias Ovarianas/genética , RNA Mensageiro/isolamento & purificação , RNA Mensageiro/metabolismo , RNA Neoplásico/metabolismo , Transfecção , Cicatrização
19.
J Surg Res ; 138(2): 163-9, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17257620

RESUMO

INTRODUCTION: Resveratrol is a phenolic compound found in grape skins, mulberries, and certain nuts that has been shown to have antitumorigenic and anti-inflammatory properties. Macrophage inhibitory cytokine (MIC-1) is a member of the transforming growth factor beta (TGF-beta) superfamily that has been shown to have antitumorigenic activity and is up-regulated in resveratrol-treated cancer cells. Resveratrol inhibits proliferation of human pancreatic cancer cells; however, the exact mechanism of action is not known. In this study, we investigated the role of MIC-1 in resveratrol-induced growth inhibition of human pancreatic cancer cell lines. METHODS AND RESULTS: Proliferation assays conducted with resveratrol-treated human pancreatic cancer cell lines (CD18 and S2-013) at 24, 48, and 72 h revealed inhibition of cell proliferation compared to controls. Using oligonucleotide microarray analysis, we identified marked up-regulation of MIC-1 gene expression in resveratrol-treated human pancreatic cancer S2-013 cells. Real-time RT-PCR performed in CD18 and S2-013 cells treated with resveratrol (0-100 mum) for 24 h confirmed concentration and time-dependent up-regulation of expression of one particular gene, MIC-1. Both cell lines pretreated with actinomycin D (a transcriptional inhibitor) and then resveratrol had reduced up-regulation of MIC-1 gene expression compared to those treated with resveratrol alone. Finally, resveratrol-induced growth inhibition was abolished in CD18 cells transfected with MIC-1 short interfering RNA. CONCLUSIONS: Resveratrol up-regulates MIC-1 gene expression in part at the transcriptional level in pancreatic cancer cells. Furthermore, MIC-1 appears to play a key role in resveratrol-induced growth inhibition in these cells.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Proteínas Morfogenéticas Ósseas/genética , Neoplasias Pancreáticas/patologia , Estilbenos/farmacologia , Divisão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Dactinomicina/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Fator 15 de Diferenciação de Crescimento , Humanos , Inibidores da Síntese de Ácido Nucleico/farmacologia , Análise de Sequência com Séries de Oligonucleotídeos , Neoplasias Pancreáticas/fisiopatologia , RNA Interferente Pequeno , Resveratrol , Transcrição Gênica/efeitos dos fármacos , Transfecção , Regulação para Cima/efeitos dos fármacos
20.
J Biomol Tech ; 18(5): 321-30, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18166675

RESUMO

Confirmation of gene expression by a second methodology is critical in order to detect false-positive findings associated with microarrays. However, the impact of methodology upon the measurement of gene expression has not been rigorously evaluated. In the current study, we compared differential gene expression between PC3 and PC3-M human prostate cancer cell lines using three separate methods: microarray, quantitative RT/PCR (qRT/PCR), and Northern blotting. The PC3 to PC3-M ratio of gene expression was determined for each of 24 different genes evaluated, by each of the three methods. Comparison of gene expression ratios between Northern and microarray, Northern and qRT/PCR, and microarray and qRT/PCR, gave correlation coefficients (r) of 0.72, 0.39, and 0.63, respectively. In each instance, one to two outlier genes were apparent. Their exclusion from analysis gave r values of 0.79, 0.72, and 0.83, respectively. These findings demonstrate that the assessment of differential gene expression is dependent upon the methodology used in each situation where outcome between different methodologies was compared, the presence of a relatively limited number of outlier genes precludes high overall correlation between the methods. Validation of gene expression by different methods should be performed whenever possible.


Assuntos
Northern Blotting , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica/fisiologia , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Northern Blotting/métodos , Linhagem Celular Tumoral , Humanos , Masculino , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos
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