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1.
BMC Dev Biol ; 16(1): 17, 2016 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-27188461

RESUMO

BACKGROUND: The RNA polymerase II transcriptional Mediator subunit Med12 is broadly implicated in vertebrate brain development, and genetic variation in human MED12 is associated with X-linked intellectual disability and neuropsychiatric disorders. Although prior studies have begun to elaborate the functional contribution of Med12 within key neurodevelopmental pathways, a more complete description of Med12 function in the developing nervous system, including the specific biological networks and cellular processes under its regulatory influence, remains to be established. Herein, we sought to clarify the global contribution of Med12 to neural stem cell (NSC) biology through unbiased transcriptome profiling of mouse embryonic stem (ES) cell-derived NSCs following RNAi-mediated Med12 depletion. RESULTS: A total of 240 genes (177 up, 73 down) were differentially expressed in Med12-knockdown versus control mouse NS-5 (mNS-5) NSCs. Gene set enrichment analysis revealed Med12 to be prominently linked with "cell-to-cell interaction" and "cell cycle" networks, and subsequent functional studies confirmed these associations. Targeted depletion of Med12 led to enhanced NSC adhesion and upregulation of cell adhesion genes, including Syndecan 2 (Sdc2). Concomitant depletion of both Sdc2 and Med12 reversed enhanced cell adhesion triggered by Med12 knockdown alone, confirming that Med12 negatively regulates NSC cell adhesion by suppressing the expression of cell adhesion molecules. Med12-mediated suppression of NSC adhesion is a dynamically regulated process in vitro, enforced in self-renewing NSCs and alleviated during the course of neuronal differentiation. Accordingly, Med12 depletion enhanced adhesion and prolonged survival of mNS-5 NSCs induced to differentiate on gelatin, effects that were bypassed completely by growth on laminin. On the other hand, Med12 depletion in mNS-5 NSCs led to reduced expression of G1/S phase cell cycle regulators and a concordant G1/S phase cell cycle block without evidence of apoptosis, resulting in a severe proliferation defect. CONCLUSIONS: Med12 contributes to the maintenance of NSC identity through a functionally bipartite role in suppression and activation of gene expression programs dedicated to cell adhesion and G1/S phase cell cycle progression, respectively. Med12 may thus contribute to the regulatory apparatus that controls the balance between NSC self-renewal and differentiation, with important implications for MED12-linked neurodevelopmental disorders.


Assuntos
Perfilação da Expressão Gênica/métodos , Complexo Mediador/genética , Células-Tronco Embrionárias Murinas/citologia , Células-Tronco Neurais/citologia , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Animais , Adesão Celular , Ciclo Celular , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Regulação da Expressão Gênica , Redes Reguladoras de Genes , Complexo Mediador/metabolismo , Camundongos , Camundongos Knockout , Células-Tronco Embrionárias Murinas/metabolismo , Células-Tronco Neurais/metabolismo
2.
J Biol Chem ; 289(35): 24691-9, 2014 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-25028521

RESUMO

Inactivating mutations of the gene encoding the tricarboxylic acid cycle enzyme fumarate hydratase (FH) have been linked to an aggressive variant of hereditary kidney cancer (hereditary leiomyomatosis and renal cell cancer). These tumors accumulate markedly elevated levels of fumarate. Fumarate is among a growing list of oncometabolites identified in cancers with mutations of genes involved in intermediary metabolism. FH-deficient tumors are notable for their pronounced accumulation of the transcription factor hypoxia inducible factor-1α (HIF-1α) and aggressive behavior. To date, HIF-1α accumulation in hereditary leiomyomatosis and renal cell cancer tumors is thought to result from fumarate-dependent inhibition of prolyl hydroxylases and subsequent evasion from von Hippel-Lindau-dependent degradation. Here, we demonstrate a novel mechanism by which fumarate promotes HIF-1α mRNA and protein accumulation independent of the von Hippel-Lindau pathway. Here we demonstrate that fumarate promotes p65 phosphorylation and p65 accumulation at the HIF-1α promoter through non-canonical signaling via the upstream Tank binding kinase 1 (TBK1). Consistent with these data, inhibition of the TBK1/p65 axis blocks HIF-1α accumulation in cellular models of FH loss and markedly reduces cell invasion of FH-deficient RCC cancer cells. Collectively, our data demonstrate a novel mechanism by which pseudohypoxia is promoted in FH-deficient tumors and identifies TBK1 as a novel putative therapeutic target for the treatment of aggressive fumarate-driven tumors.


Assuntos
Hipóxia Celular , Fumaratos/metabolismo , NF-kappa B/metabolismo , Transdução de Sinais , Sequência de Bases , Linhagem Celular , Imunoprecipitação da Cromatina , Primers do DNA , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Fosforilação , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real
3.
J Immunol ; 185(5): 2747-53, 2010 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-20686128

RESUMO

CD4(+)CD25(+)Foxp3(+) regulatory T cells (Tregs) are immunopathogenic in cancers by impeding tumor-specific immunity. B7-homologue 1 (B7-H1) (CD274) is a cosignaling molecule with pleiotropic effects, including hindering antitumor immunity. In this study, we demonstrate sex-dependent, B7-H1-dependent differences in tumor immunity and response to immunotherapy in a hormone-independent cancer, murine B16 melanoma. Antitumor immunity was better in B7-H1(-/-) females versus males as a result of reduced regulatory T cell function in the B7-H1(-/-) females, and clinical response following B7-H1 blockade as tumor immunotherapy was significantly better in wild-type females than in males, owing to greater B7-H1 blockade-mediated reduction of Treg function in females. Wild-type female Tregs expressed significantly lower B7-H1 versus males but were insensitive to estrogen in vitro. Female B7-H1(-/-) Tregs were exquisitely sensitive to estrogen-mediated functional reduction in vitro, suggesting that B7-H1 effects occur before terminal Treg differentiation. Immune differences were independent of known B7-H1 ligands. Sex-dependent immune differences are seldom considered in designing immune therapy or interpreting immunotherapy treatment results. Our data demonstrate that sex is an important variable in tumor immunopathogenesis and immunotherapy responses through differential Treg function and B7-H1 signaling.


Assuntos
Antígeno B7-1/fisiologia , Imunoterapia Adotiva/métodos , Melanoma Experimental/imunologia , Melanoma Experimental/terapia , Glicoproteínas de Membrana/fisiologia , Peptídeos/fisiologia , Caracteres Sexuais , Animais , Antígenos de Diferenciação/fisiologia , Antígeno B7-1/genética , Antígeno B7-H1 , Linhagem Celular Tumoral , Feminino , Imunidade Inata/genética , Masculino , Melanoma Experimental/fisiopatologia , Glicoproteínas de Membrana/deficiência , Glicoproteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Ovalbumina/biossíntese , Ovalbumina/genética , Ovalbumina/imunologia , Peptídeos/deficiência , Peptídeos/genética , Receptor de Morte Celular Programada 1 , Transdução de Sinais/genética , Transdução de Sinais/imunologia , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Linfócitos T Reguladores/patologia
4.
J Exp Med ; 217(6)2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32251515

RESUMO

Analysis of transcriptomic data demonstrates extensive epigenetic gene silencing of the transcription factor PRDM16 in renal cancer. We show that restoration of PRDM16 in RCC cells suppresses in vivo tumor growth. RNaseq analysis reveals that PRDM16 imparts a predominantly repressive effect on the RCC transcriptome including suppression of the gene encoding semaphorin 5B (SEMA5B). SEMA5B is a HIF target gene highly expressed in RCC that promotes in vivo tumor growth. Functional studies demonstrate that PRDM16's repressive properties, mediated by physical interaction with the transcriptional corepressors C-terminal binding proteins (CtBP1/2), are required for suppression of both SEMA5B expression and in vivo tumor growth. Finally, we show that reconstitution of RCC cells with a PRDM16 mutant unable to bind CtBPs nullifies PRDM16's effects on both SEMA5B repression and tumor growth suppression. Collectively, our data uncover a novel epigenetic basis by which HIF target gene expression is amplified in kidney cancer and a new mechanism by which PRDM16 exerts its tumor suppressive effects.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Regulação Neoplásica da Expressão Gênica , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Neoplasias Renais/genética , Fatores de Transcrição/metabolismo , Oxirredutases do Álcool/metabolismo , Animais , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/patologia , Movimento Celular/efeitos dos fármacos , Movimento Celular/genética , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Colforsina/farmacologia , Metilação de DNA/genética , Epigênese Genética/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Inativação Gênica/efeitos dos fármacos , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Neoplasias Renais/patologia , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Camundongos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Modelos Biológicos , Fenótipo , Regiões Promotoras Genéticas/genética , Rosiglitazona/farmacologia , Semaforinas/genética , Semaforinas/metabolismo , Transcrição Gênica/efeitos dos fármacos , Cicatrização/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Mol Cancer Res ; 17(1): 84-96, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30131446

RESUMO

The Cancer Genome Atlas (TCGA) and other large-scale genomic data pipelines have been integral to the current understanding of the molecular events underlying renal cell carcinoma (RCC). These data networks have focused mostly on primary RCC, which often demonstrates indolent behavior. However, metastatic disease is the major cause of mortality associated with RCC and data sets examining metastatic tumors are sparse. Therefore, a more comprehensive analysis of gene expression and DNA methylome profiling of metastatic RCC in addition to primary RCC and normal kidney was performed. Integrative analysis of the methylome and transcriptome identified over 30 RCC-specific genes whose mRNA expression inversely correlated with promoter methylation, including several known targets of hypoxia inducible factors. Notably, genes encoding several metabolism-related proteins were identified as differentially regulated via methylation including hexokinase 2, aldolase C, stearoyl-CoA desaturase, and estrogen-related receptor-γ (ESRRG), which has a known role in the regulation of nuclear-encoded mitochondrial metabolism genes. Several gene expression changes could portend prognosis in the TCGA cohort. Mechanistically, ESRRG loss occurs via DNA methylation and histone repressive silencing mediated by the polycomb repressor complex 2. Restoration of ESRRG in RCC lines suppresses migratory and invasive phenotypes independently of its canonical role in mitochondrial metabolism. IMPLICATIONS: Collectively, these data provide significant insight into the biology of aggressive RCC and demonstrate a novel role for DNA methylation in the promotion of HIF signaling and invasive phenotypes in renal cancer.


Assuntos
Epigenômica/métodos , Regulação Neoplásica da Expressão Gênica/genética , Neoplasias Renais/genética , Progressão da Doença , Humanos , Neoplasias Renais/patologia , Metástase Neoplásica
6.
Cancer Immunol Res ; 7(3): 466-475, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30563829

RESUMO

The mechanistic target of rapamycin (mTOR) integrates environmental inputs to regulate cellular growth and metabolism in tumors. However, mTOR also regulates T-cell differentiation and activation, rendering applications of mTOR inhibitors toward treating cancer complex. Preclinical data support distinct biphasic effects of rapamycin, with higher doses directly suppressing tumor cell growth and lower doses enhancing T-cell immunity. To address the translational relevance of these findings, the effects of the mTOR complex 1 (mTORC1) inhibitor, rapamycin, on tumor and T cells were monitored in patients undergoing cystectomy for bladder cancer. MB49 syngeneic murine bladder cancer models were tested to gain mechanistic insights. Surgery-induced T-cell exhaustion in humans and mice and was associated with increased pulmonary metastasis and decreased PD-L1 antibody efficacy in mouse bladder cancer. At 3 mg orally daily, rapamycin concentrations were 2-fold higher in bladder tissues than in blood. Rapamycin significantly inhibited tumor mTORC1, shown by decreased rpS6 phosphorylation in treated versus control patients (P = 0.008). Rapamycin reduced surgery-induced T-cell exhaustion in patients, evidenced by a significant decrease in the prevalence of dysfunctional programmed death-1 (PD-1)-expressing T cells. Grade 3 to 4 adverse event rates were similar between groups, but rapamycin-treated patients had a higher rate of wound complications versus controls. In conclusion, surgery promoted bladder cancer metastasis and decreased the efficacy of postoperative bladder cancer immunotherapy. Low-dose (3 mg daily) oral rapamycin has favorable pharmacodynamic and immune modulating activity in surgical patients and has the potential to decrease surgery-induced immune dysfunction.


Assuntos
Complicações Pós-Operatórias/prevenção & controle , Sirolimo/uso terapêutico , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/cirurgia , Idoso , Animais , Antígeno B7-H1/antagonistas & inibidores , Proliferação de Células , Cistectomia/efeitos adversos , Modelos Animais de Doenças , Feminino , Humanos , Masculino , Alvo Mecanístico do Complexo 1 de Rapamicina/antagonistas & inibidores , Camundongos , Camundongos Endogâmicos C57BL , Fosforilação/efeitos dos fármacos , Complicações Pós-Operatórias/imunologia , Receptor de Morte Celular Programada 1 , Proteína S6 Ribossômica/metabolismo , Sirolimo/administração & dosagem , Sirolimo/efeitos adversos , Sirolimo/farmacocinética , Linfócitos T/imunologia , Bexiga Urinária/efeitos dos fármacos , Bexiga Urinária/patologia , Bexiga Urinária/cirurgia , Neoplasias da Bexiga Urinária/imunologia , Neoplasias da Bexiga Urinária/patologia
7.
RNA Biol ; 5(4): 255-62, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18971640

RESUMO

Eukaryotic gene expression must be coordinated for the proper functioning of biological processes. This coordination can be achieved both at the transcriptional and post-transcriptional levels. In both cases, regulatory sequences placed at either promoter regions or on UTRs function as markers recognized by regulators that can then activate or repress different groups of genes according to necessity. While regulatory sequences involved in transcription are quite well documented, there is a lack of information on sequence elements involved in post-transcriptional regulation. We used a statistical over-representation method to identify novel regulatory elements located on UTRs. An exhaustive search approach was used to calculate the frequency of all possible n-mers (short nucleotide sequences) in 16,160 human genes of NCBI RefSeq sequences and to identify any peculiar usage of n-mers on UTRs. After a stringent filtering process, we identified 2,772 highly over-represented n-mers on 3' UTRs. We provide evidence that these n-mers are potentially involved in regulatory functions. Identified n-mers overlap with previously identified binding sites for HuR and TIA-1 and, ARE and GRE sequences. We determine also that n-mers overlap with predicted miRNA target sites. Finally, a method to cluster n-mer groups allowed the identification of putative gene networks.


Assuntos
Regiões 3' não Traduzidas/genética , Sequências Reguladoras de Ácido Nucleico/genética , Sequência de Bases , Sítios de Ligação , Análise por Conglomerados , Regulação da Expressão Gênica , Redes Reguladoras de Genes , Humanos , MicroRNAs/genética , Dados de Sequência Molecular , Óperon/genética , Transcrição Gênica
8.
Methods Mol Biol ; 1783: 81-104, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29767358

RESUMO

Gene expression profiling of samples from biobanks requires a method that can be used with intact as well as partially degraded RNA. High throughput applications can benefit from reducing the number of processing steps including eliminating the poly(A) selection and ribosomal depletion steps. When performing targeted capture, we have found that we can eliminate the upfront poly(A) selection/ribosomal depletion steps that cause bias in standard mRNA-Seq workflows. This target enrichment solution allows for whole transcriptome or customized content to characterize differential gene expression patterns (especially for mid/low level transcripts). Protocol modifications to the Agilent Strand-Specific RNA Library Prep kit resulted in a new workflow called "RNA Direct" that generates RNA-Seq data with minimal ribosomal contamination and good sequencing coverage. Using RNA isolated from a set of matched samples including fresh frozen (FF) or formalin-fixed, paraffin-embedded (FFPE) from tumor/normal tissues we generated high-quality data using a protocol that does not require upfront ribosomal depletion or poly(A) selection. Using SureSelectXT RNA Direct protocol (RNA Direct) workflow, we found transcripts to be upregulated or downregulated to similar degrees with similar confidence levels in both the FF and FFPE samples, demonstrating the utility for meaningful gene expression studies with biobank samples of variable quality.


Assuntos
Biomarcadores/análise , Perfilação da Expressão Gênica/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Neoplasias/genética , RNA/genética , Análise de Sequência de RNA/métodos , Transcriptoma , Biblioteca Gênica , Humanos , Inclusão em Parafina , RNA/isolamento & purificação , Fixação de Tecidos , Fluxo de Trabalho
9.
J Obes ; 2018: 9247864, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29887999

RESUMO

Background: Obesity is associated with an increased risk of bladder cancer recurrence. This study investigated the role of adipose tissue in bladder cancer progression. Methods: Gene expression profiling was performed on adipose tissues collected from normal weight (n=5), overweight (n=11), and obese (n=10) patients with invasive bladder cancer, and adipose stromal cells (ASCs) were obtained from two normal weight, two overweight, and two obese patients. Conditioned media (CM) was characterized and evaluated for its effects on the proliferation, migration, and invasive potential of T24 bladder cancer cells. Results: Expression profiling demonstrated depot-specific or body mass index-specific differences. Increased T24 cell migration was observed using CM harvested from all ASCs. ASC CM from an obese patient significantly increased T24 cell migration and invasion compared to ASC CM collected from normal weight and overweight patients. We identified abundant expression of CXCL1, PAI1, IL6, CX3CL1, and CCL2 in all CM. Exogenous treatment of T24 cells with PAI1, IL6, and CXCL1 enhanced migration. Depletion of CXCL1, PAI1, and IL6 in an obese patient ASC CM abrogated T24 migration. Conclusion: Factors secreted by adipose tissue influence the migration of bladder tumor cells and could play an active role in tumor progression.


Assuntos
Tecido Adiposo/metabolismo , Índice de Massa Corporal , Movimento Celular , Quimiocinas/metabolismo , Citocinas/metabolismo , Neoplasias da Bexiga Urinária/patologia , Adipócitos/metabolismo , Idoso , Idoso de 80 Anos ou mais , Linhagem Celular Tumoral , Células Cultivadas , Meios de Cultivo Condicionados , Humanos , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Obesidade/metabolismo , Sobrepeso/metabolismo , Transcriptoma
10.
Gene Expr Patterns ; 7(1-2): 1-7, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16798107

RESUMO

The sea urchin regulatory gene Spblimp1/krox produces alternatively transcribed and spliced isoforms, 1a and 1b, which have different temporal and spatial patterns of expression. Here we describe a cis-regulatory module that controls the expression of the 1a splice form in the midgut and hindgut at the beginning of gastrulation. Conserved sequence patches revealed by a comparison of the blimp1/krox locus in Strongylocentrotus purpuratus and Lytechinus variegatus genomes were tested by gene transfer, in association with GFP or CAT reporter genes. An expression construct containing a conserved sequence patch immediately 5' of exon 1a included the transcription initiation site for blimp1/krox1a. This construct displays specific mid and hindgut expression, indicating that these are the locations of endogenous blimp1/krox1a transcription during the gastrula stage. Its sequence contains binding sites for Brn1/2/4, Otx, and Blimp1/Krox itself, as predicted in a prior regulatory network analysis.


Assuntos
Proteínas de Ligação a DNA/genética , Ouriços-do-Mar/genética , Fatores de Transcrição/genética , Processamento Alternativo , Animais , Animais Geneticamente Modificados , Sequência de Bases , Padronização Corporal , Cromossomos Artificiais Bacterianos/genética , DNA/genética , Sistema Digestório/crescimento & desenvolvimento , Sistema Digestório/metabolismo , Gástrula/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Lytechinus/genética , Lytechinus/crescimento & desenvolvimento , Lytechinus/metabolismo , Dados de Sequência Molecular , Ouriços-do-Mar/crescimento & desenvolvimento , Ouriços-do-Mar/metabolismo , Especificidade da Espécie , Strongylocentrotus purpuratus/genética , Strongylocentrotus purpuratus/crescimento & desenvolvimento , Strongylocentrotus purpuratus/metabolismo
11.
Artigo em Inglês | MEDLINE | ID: mdl-27237224

RESUMO

Rapamycin inhibits mechanistic (or mammalian) target of rapamycin (mTOR) that promotes protein production in cells by facilitating ribosome biogenesis (RiBi) and eIF4E-mediated 5'cap mRNA translation. Chronic treatment with encapsulated rapamycin (eRapa) extended health and life span for wild-type and cancer-prone mice. Yet, the long-term consequences of chronic eRapa treatment are not known at the organ level. Here, we report our observations of chronic eRapa treatment on mTORC1 signaling and RiBi in mouse colon and visceral adipose. As expected, chronic eRapa treatment decreased detection of phosphorylated mTORC1/S6K substrate, ribosomal protein (rpS6) in colon and fat. However, in colon, contrary to expectations, there was an upregulation of 18S rRNA and some ribosomal protein genes (RPGs) suggesting increased RiBi. Among RPGs, eRapa increases rpl22l1 mRNA but not its paralog rpl22. Furthermore, there was an increase in the cap-binding protein, eIF4E relative to its repressor 4E-BP1 suggesting increased translation. By comparison, in fat, there was a decrease in the level of 18S rRNA (opposite to colon), while overall mRNAs encoding ribosomal protein genes appeared to increase, including rpl22, but not rpl22l1 (opposite to colon). In fat, there was a decrease in eIF4E relative to actin (opposite to colon) but also an increase in the eIF4E/4E-BP1 ratio likely due to reductions in 4E-BP1 at our lower eRapa dose (similar to colon). Thus, in contrast to predictions of decreased protein production seen in cell-based studies, we provide evidence that colon from chronically treated mice exhibited an adaptive 'pseudo-anabolic' state, which is only partially present in fat, which might relate to differing tissue levels of rapamycin, cell-type-specific responses, and/or strain differences.

12.
J Gerontol A Biol Sci Med Sci ; 71(2): 153-60, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25568097

RESUMO

Age-associated decline in organ function governs life span. We determined the effect of aging on lung function and cellular/molecular changes of 8- to 32-month old mice. Proteomic analysis of lung matrix indicated significant compositional changes with advanced age consistent with a profibrotic environment that leads to a significant increase in dynamic compliance and airway resistance. The excess of matrix proteins deposition was associated modestly with the activation of myofibroblasts and transforming growth factor-beta signaling pathway. More importantly, detection of senescent cells in the lungs increased with age and these cells contributed toward the excess extracellular matrix deposition observed in our aged mouse model and in elderly human samples. Mechanistic target of rapamycin (mTOR)/AKT activity was enhanced in aged mouse lungs compared with those from younger mice associated with the increased expression of the histone variant protein, MH2A, a marker for aging and potentially for senescence. Introduction in the mouse diet of rapamycin, significantly blocked the mTOR activity and limited the activation of myofibroblasts but did not result in a reduction in lung collagen deposition unless it was associated with prevention of cellular senescence. Together these data indicate that cellular senescence significantly contributes to the extracellular matrix changes associated with aging in a mTOR 1-dependent mechanism.


Assuntos
Remodelação das Vias Aéreas/fisiologia , Senescência Celular/fisiologia , Pulmão/metabolismo , Actinas/metabolismo , Adulto , Idoso , Envelhecimento/fisiologia , Animais , Biomarcadores/metabolismo , Colágeno/metabolismo , Matriz Extracelular/metabolismo , Fibroblastos/metabolismo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Proteômica , Transdução de Sinais/fisiologia , Serina-Treonina Quinases TOR/metabolismo , Tenascina/metabolismo , Fator de Crescimento Transformador beta/metabolismo
13.
Sci Rep ; 6: 28994, 2016 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-27456714

RESUMO

Common recommendations for cell line authentication, annotation and quality control fall short addressing genetic heterogeneity. Within the Human Toxome Project, we demonstrate that there can be marked cellular and phenotypic heterogeneity in a single batch of the human breast adenocarcinoma cell line MCF-7 obtained directly from a cell bank that are invisible with the usual cell authentication by short tandem repeat (STR) markers. STR profiling just fulfills the purpose of authentication testing, which is to detect significant cross-contamination and cell line misidentification. Heterogeneity needs to be examined using additional methods. This heterogeneity can have serious consequences for reproducibility of experiments as shown by morphology, estrogenic growth dose-response, whole genome gene expression and untargeted mass-spectroscopy metabolomics for MCF-7 cells. Using Comparative Genomic Hybridization (CGH), differences were traced back to genetic heterogeneity already in the cells from the original frozen vials from the same ATCC lot, however, STR markers did not differ from ATCC reference for any sample. These findings underscore the need for additional quality assurance in Good Cell Culture Practice and cell characterization, especially using other methods such as CGH to reveal possible genomic heterogeneity and genetic drifts within cell lines.


Assuntos
Variação Genética/genética , Linhagem Celular Tumoral , Hibridização Genômica Comparativa/métodos , Perfilação da Expressão Gênica/métodos , Marcadores Genéticos/genética , Humanos , Células MCF-7 , Repetições de Microssatélites/genética , Reprodutibilidade dos Testes
14.
J Periodontol ; 86(5): 703-12, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25594425

RESUMO

BACKGROUND: A fundamental issue limiting the efficacy of surgical approaches designed to correct periodontal mucogingival defects is that new tissues rely on limited sources of blood supply from the adjacent recipient bed. Accordingly, therapies based on tissue engineering that leverage local self-healing potential may represent promising alternatives for the treatment of mucogingival defects by inducing local vascularization. The aim of this study is to evaluate the effect of commercially available living cellular sheets (LCS) on the angiogenic potential of neonatal dermal human microvascular endothelial cells (HMVEC-dNeo). METHODS: The effect of LCS on HMVEC-dNeo proliferation, migration, capillary tube formation, gene expression, and production of angiogenic factors was evaluated over time. RESULTS: LCS positively influenced HMVEC-dNeo proliferation and migration. Moreover, HMVEC-dNeo incubated with LCS showed transcriptional profiles different from those of untreated cells. Whereas increased expression of angiogenic genes predominated early on in response to LCS, late-phase responses were characterized by up- and downregulation of angiostatic and angiogenic genes. However, this trend was not confirmed at the protein level, as LCS induced increased production of most of the angiogenic factors tested (i.e., epidermal growth factor [EGF], heparin-binding EGF-like growth factor, interleukin 6, angiopoietin, platelet-derived growth factor-BB, placental growth factor, and vascular endothelial growth factor) throughout the investigational period. Finally, although LCS induced HMVEC-dNeo proliferation, migration, and expression of angiogenic factors, additional factors and environmental pressures are likely to be required to promote the development of complex, mesh-like vascular structures. CONCLUSION: LCS favor initial mechanisms that govern angiogenesis but failed to enhance or accelerate HMVEC-dNeo morphologic transition to complex vascular structures.


Assuntos
Células Endoteliais/fisiologia , Endotélio Vascular/citologia , Microvasos/citologia , Neovascularização Fisiológica/fisiologia , Alicerces Teciduais , Indutores da Angiogênese/análise , Angiopoietinas/análise , Becaplermina , Capilares/fisiologia , Movimento Celular/fisiologia , Proliferação de Células , Sobrevivência Celular/fisiologia , Colágeno Tipo I/química , Fator de Crescimento Epidérmico/análise , Fibroblastos/fisiologia , Regulação da Expressão Gênica/genética , Fator de Crescimento Semelhante a EGF de Ligação à Heparina/análise , Humanos , Interleucina-6/análise , Queratinócitos/fisiologia , Neovascularização Fisiológica/genética , Fator de Crescimento Placentário , Proteínas da Gravidez/análise , Proteínas Proto-Oncogênicas c-sis/análise , Engenharia Tecidual/métodos , Alicerces Teciduais/química , Fator A de Crescimento do Endotélio Vascular/análise
15.
Front Pharmacol ; 6: 322, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26924983

RESUMO

The Human Toxome Project is part of a long-term vision to modernize toxicity testing for the 21st century. In the initial phase of the project, a consortium of six academic, commercial, and government organizations has partnered to map pathways of toxicity, using endocrine disruption as a model hazard. Experimental data is generated at multiple sites, and analyzed using a range of computational tools. While effectively gathering, managing, and analyzing the data for high-content experiments is a challenge in its own right, doing so for a growing number of -omics technologies, with larger data sets, across multiple institutions complicates the process. Interestingly, one of the most difficult, ongoing challenges has been the computational collaboration between the geographically separate institutions. Existing solutions cannot handle the growing heterogeneous data, provide a computational environment for consistent analysis, accommodate different workflows, and adapt to the constantly evolving methods and goals of a research project. To meet the needs of the project, we have created and managed The Human Toxome Collaboratorium, a shared computational environment hosted on third-party cloud services. The Collaboratorium provides a familiar virtual desktop, with a mix of commercial, open-source, and custom-built applications. It shares some of the challenges of traditional information technology, but with unique and unexpected constraints that emerge from the cloud. Here we describe the problems we faced, the current architecture of the solution, an example of its use, the major lessons we learned, and the future potential of the concept. In particular, the Collaboratorium represents a novel distribution method that could increase the reproducibility and reusability of results from similar large, multi-omic studies.

16.
Oncotarget ; 6(18): 15802-13, 2015 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-26158292

RESUMO

Mechanistic target of rapamycin (mTOR) is a kinase found in a complex (mTORC1) that enables macromolecular synthesis and cell growth and is implicated in cancer etiology. The rapamycin-FK506 binding protein 12 (FKBP12) complex allosterically inhibits mTORC1. In response to stress, p53 inhibits mTORC1 through a separate pathway involving cell signaling and amino acid sensing. Thus, these different mechanisms could be additive. Here we show that p53 improved the ability of rapamycin to: 1) extend mouse life span, 2) suppress ionizing radiation (IR)-induced senescence-associated secretory phenotype (SASP) and 3) increase the levels of amino acids and citric acid in mouse embryonic stem (ES) cells. This additive effect could have implications for cancer treatment since rapamycin and p53 are anti-oncogenic.


Assuntos
Sirolimo/farmacologia , Proteína Supressora de Tumor p53/metabolismo , Animais , Linhagem Celular , Proliferação de Células , Células-Tronco Embrionárias/efeitos dos fármacos , Células-Tronco Embrionárias/metabolismo , Feminino , Fibroblastos , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Transdução de Sinais , Sirolimo/sangue , Sirolimo/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Proteína Supressora de Tumor p53/biossíntese , Proteína Supressora de Tumor p53/genética
17.
ALTEX ; 32(2): 112-24, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25742299

RESUMO

The Human Toxome Project, funded as an NIH Transformative Research grant 2011-2016, is focused on developing the concepts and the means for deducing, validating and sharing molecular pathways of toxicity (PoT). Using the test case of estrogenic endocrine disruption, the responses of MCF-7 human breast cancer cells are being phenotyped by transcriptomics and mass-spectroscopy-based metabolomics. The bioinformatics tools for PoT deduction represent a core deliverable. A number of challenges for quality and standardization of cell systems, omics technologies and bioinformatics are being addressed. In parallel, concepts for annotation, validation and sharing of PoT information, as well as their link to adverse outcomes, are being developed. A reasonably comprehensive public database of PoT, the Human Toxome Knowledge-base, could become a point of reference for toxicological research and regulatory test strategies.


Assuntos
Toxicologia/métodos , Alternativas aos Testes com Animais , Animais , Bases de Dados Factuais , Disruptores Endócrinos , Humanos , Metabolômica , Camundongos , Testes de Toxicidade/métodos , Transcriptoma
18.
Mech Ageing Dev ; 140: 23-9, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25075714

RESUMO

Rapamycin, a drug that has been shown to increase lifespan in mice, inhibits the target of rapamycin (TOR) pathway, a major pathway that regulates cell growth and energy status. It has been hypothesized that rapamycin and dietary restriction (DR) extend lifespan through similar mechanisms/pathways. Using microarray analysis, we compared the transcriptome of white adipose tissue from mice fed rapamycin or DR-diet for 6 months. Multidimensional scaling and heatmap analyses showed that rapamycin had essentially no effect on the transcriptome as compared to DR. For example, only six transcripts were significantly altered by rapamycin while mice fed DR showed a significant change in over 1000 transcripts. Using ingenuity pathway analysis, we found that stearate biosynthesis and circadian rhythm signaling were significantly changed by DR. Our findings showing that DR, but not rapamycin, has an effect on the transcriptome of the adipose tissue, suggesting that these two manipulations increase lifespan through different mechanisms/pathways.


Assuntos
Tecido Adiposo Branco/química , Privação de Alimentos , Sirolimo/administração & dosagem , Transcriptoma/efeitos dos fármacos , Tecido Adiposo Branco/efeitos dos fármacos , Tecido Adiposo Branco/metabolismo , Animais , Restrição Calórica , Dieta , Longevidade/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Análise em Microsséries , Serina-Treonina Quinases TOR/antagonistas & inibidores
19.
Cancer Epidemiol Biomarkers Prev ; 23(2): 309-15, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24296854

RESUMO

BACKGROUND: Adiponectin has been reported to have a prohibitory effect on prostate cancer. The goal of this study was to evaluate the diagnostic value of adiponectin multimers for prostate cancer. METHODS: Total adiponectin, high- and low-molecular-weight (HMW, LMW), ratios of these measures, and body mass index (BMI) were compared in a prospective prostate cancer-screened cohort. Multivariable logistic regression was used to assess the association between adiponectin measures, their interaction with BMI, and risk of prostate cancer and Gleason score upgrading from biopsy to prostatectomy. RESULTS: A total of 228 prostate cancer cases and 239 controls were analyzed: 72 (31.6%) of the cancer cases were high grade (Gleason grade ≥7). Only percent HMW had a statistically significant relationship with prostate cancer (P = 0.04). Among normal and overweight men, the risk of prostate cancer increased as percent HMW increased [OR = 1.24 for a doubling of percent HMW, 95% confidence interval (CI), 0.41-3.75 and OR = 1.81; 95% CI, 1.02-3.20, respectively], whereas among obese men, the risk of prostate cancer decreased (OR = 0.62; 95% CI, 0.32-1.18). Among 97 patients who underwent radical prostatectomy, there was no association between Gleason score upgrading and any of the adiponectin multimers. CONCLUSION: This study was unable to confirm the utility of total adiponectin as a biomarker for prostate cancer risk. For the adiponectin multimers, only HMW showed increases with prostate cancer but not in all weight classes. IMPACT: Although adiponectin may play a role in the pathogenesis of prostate cancer, our results do not support adiponectin multimers as biomarkers of detection.


Assuntos
Adiponectina/metabolismo , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/metabolismo , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/metabolismo , Estudos de Casos e Controles , Estudos de Coortes , Detecção Precoce de Câncer/métodos , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/metabolismo , Obesidade/patologia , Neoplasias da Próstata/patologia , Fatores de Risco
20.
PLoS One ; 9(4): e94522, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24732672

RESUMO

The function of prostate-specific antigen (PSA) is to liquefy the semen coagulum so that the released sperm can fuse with the ovum. Fifteen spliced variants of the PSA gene have been reported in humans, but little is known about alternative splicing in nonhuman primates. Positive selection has been reported in sex- and reproductive-related genes from sea urchins to Drosophila to humans; however, there are few studies of adaptive evolution of the PSA gene. Here, using polymerase chain reaction (PCR) product cloning and sequencing, we study PSA transcript variant heterogeneity in the prostates of chimpanzees (Pan troglodytes), cynomolgus monkeys (Macaca fascicularis), baboons (Papio hamadryas anubis), and African green monkeys (Chlorocebus aethiops). Six PSA variants were identified in the chimpanzee prostate, but only two variants were found in cynomolgus monkeys, baboons, and African green monkeys. In the chimpanzee the full-length transcript is expressed at the same magnitude as the transcripts that retain intron 3. We have found previously unidentified splice variants of the PSA gene, some of which might be linked to disease conditions. Selection on the PSA gene was studied in 11 primate species by computational methods using the sequences reported here for African green monkey, cynomolgus monkey, baboon, and chimpanzee and other sequences available in public databases. A codon-based analysis (dN/dS) of the PSA gene identified potential adaptive evolution at five residue sites (Arg45, Lys70, Gln144, Pro189, and Thr203).


Assuntos
Chlorocebus aethiops/genética , Pan troglodytes/genética , Papio/genética , Antígeno Prostático Específico/genética , Processamento Alternativo/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Teorema de Bayes , Clonagem Molecular , Códon/genética , Íntrons/genética , Funções Verossimilhança , Macaca fascicularis , Masculino , Dados de Sequência Molecular , Filogenia , Antígeno Prostático Específico/química , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real
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