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1.
BMC Urol ; 21(1): 36, 2021 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-33691672

RESUMO

BACKGROUND: WW Domain Containing Oxidoreductase (WWOX) belongs to the unusual tumor suppressors, whose molecular function is not fully understood in bladder cancer, especially regarding interaction with Activator Protein 2 (AP-2) α/γ transcription factors. Thus, using lentiviral systems we created an in vitro model overexpressing or downregulating WWOX in CAL-29 cell line to assess invasiveness pathways. Surprisingly, while WWOX overexpression was accompanied with increased expression of both AP-2 factors, its downregulation only affected AP-2α level but not AP-2γ which remained high. METHODS: Using cellular models and unpaired t-test or Wilcoxon test, we investigated significant changes in biological processes: clonogenicity, extracellular matrix adhesion, metalloproteinases activity, 3D culture growth, proliferation, mitochondrial redox potential and invasiveness. Relative gene expression acquired through Real-Time qPCR has been analyzed by Welch's t-test. Additionally, using oncoprint analysis we distinguished groups for bioinformatics analyzes in order to perform a follow-up of in vitro experiments. RESULTS: Downregulation of WWOX in bladder cancer cell line intensified ability of single cell to grow into colony, mitochondrial redox potential and proliferation rate. Moreover, these cells shown elevated pro-MMP-2/9 activity but reduced adhesion to collagen I or laminin I, as well as distinct 3D culture growth. Through global in silico profiling we determined that WWOX alters disease-free survival of bladder cancer patients and modulates vital processes through AP-2 downstream effectors. CONCLUSIONS: Our research indicates that WWOX possesses tumor suppressor properties in bladder cancer but consecutive examination is required to entirely understand the contribution of AP-2γ or AP-2α.


Assuntos
Regulação Neoplásica da Expressão Gênica , Fator de Transcrição AP-2/fisiologia , Proteínas Supressoras de Tumor/genética , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/patologia , Oxidorredutase com Domínios WW/genética , Linhagem Celular Tumoral , Simulação por Computador , Humanos , Invasividade Neoplásica/genética
2.
Science ; 370(6522)2020 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-33303584

RESUMO

Embryo polarization is critical for mouse development; however, neither the regulatory clock nor the molecular trigger that it activates is known. Here, we show that the embryo polarization clock reflects the onset of zygotic genome activation, and we identify three factors required to trigger polarization. Advancing the timing of transcription factor AP-2 gamma (Tfap2c) and TEA domain transcription factor 4 (Tead4) expression in the presence of activated Ras homolog family member A (RhoA) induces precocious polarization as well as subsequent cell fate specification and morphogenesis. Tfap2c and Tead4 induce expression of actin regulators that control the recruitment of apical proteins on the membrane, whereas RhoA regulates their lateral mobility, allowing the emergence of the apical domain. Thus, Tfap2c, Tead4, and RhoA are regulators for the onset of polarization and cell fate segregation in the mouse.


Assuntos
Relógios Biológicos/fisiologia , Blastocisto/fisiologia , Polaridade Celular/fisiologia , Proteínas de Ligação a DNA/fisiologia , Proteínas Musculares/fisiologia , Fator de Transcrição AP-2/fisiologia , Fatores de Transcrição/fisiologia , Proteína rhoA de Ligação ao GTP/fisiologia , Actinas/metabolismo , Animais , Relógios Biológicos/genética , Blastocisto/citologia , Diferenciação Celular/genética , Diferenciação Celular/fisiologia , Polaridade Celular/genética , Proteínas do Citoesqueleto/metabolismo , Proteínas de Ligação a DNA/genética , Desenvolvimento Embrionário/genética , Desenvolvimento Embrionário/fisiologia , Feminino , Técnicas de Silenciamento de Genes , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Musculares/genética , Interferência de RNA , Fatores de Transcrição de Domínio TEA , Fator de Transcrição AP-2/genética , Fatores de Transcrição/genética , Proteína rhoA de Ligação ao GTP/genética
3.
BMC Med Genomics ; 13(1): 174, 2020 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-33213447

RESUMO

BACKGROUND: Among all causes of death, cancer is the most prevalent and is only outpaced by cardiovascular diseases. Molecular theory of carcinogenesis states that apoptosis and proliferation are regulated by groups of tumor suppressors or oncogenes. Transcription factors are example of proteins comprising representatives of both cancer-related groups. Exemplary family of transcription factors which exhibits dualism of function is Activating enhancer-binding Protein 2 (AP-2). Scientific reports concerning their function in carcinogenesis depend on particular family member and/or tumor type which proves the issue to be unsolved. Therefore, the present study examines role of the best-described AP-2 representatives, AP-2α and AP-2γ, through ontological analysis of their target genes and investigation what processes are differentially regulated in 21 cancers using samples deposited in Genomic Data Analysis Center (GDAC) Firehose. METHODS: Expression data with clinical annotation was collected from TCGA-dedicated repository GDAC Firehose. Transcription factor targets were obtained from Gene Transcription Regulation Database (GTRD), TRANScription FACtor database (TRANSFAC) and Transcriptional Regulatory Relationships Unraveled by Sentence-based Text mining (TRRUST). Monocle3 R package was used for global samples profiling while Protein ANalysis THrough Evolutionary Relationships (PANTHER) tool was used to perform gene ontology analysis. RESULTS: With RNA-seq data and Monocle3 or PANTHER tools we outlined differences in many processes and signaling pathways, separating tumor from normal tissues or tumors from each other. Unexpectedly, a number of alterations in basal-like breast cancer were identified that distinguished it from other subtypes, which could bring future clinical benefits. CONCLUSIONS: Our findings indicate that while the AP-2α/γ role remains ambiguous, their activity is based on processes that underlie the cancer hallmarks and their expression could have potential in diagnosis of selected tumors.


Assuntos
Proteínas de Neoplasias/genética , Neoplasias/genética , Fator de Transcrição AP-2/genética , Neoplasias da Mama/classificação , Neoplasias da Mama/genética , Carcinogênese/genética , Análise por Conglomerados , Simulação por Computador , Feminino , Regulação Neoplásica da Expressão Gênica , Ontologia Genética , Humanos , Masculino , Anotação de Sequência Molecular , Proteínas de Neoplasias/fisiologia , RNA-Seq , Transdução de Sinais/genética , Fator de Transcrição AP-2/fisiologia , Transcrição Gênica/genética
4.
Science ; 367(6479): 757-762, 2020 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-32054756

RESUMO

Clonal animals do not sequester a germ line during embryogenesis. Instead, they have adult stem cells that contribute to somatic tissues or gametes. How germ fate is induced in these animals, and whether this process is related to bilaterian embryonic germline induction, is unknown. We show that transcription factor AP2 (Tfap2), a regulator of mammalian germ lines, acts to commit adult stem cells, known as i-cells, to the germ cell fate in the clonal cnidarian Hydractinia symbiolongicarpus Tfap2 mutants lacked germ cells and gonads. Transplanted wild-type cells rescued gonad development but not germ cell induction in Tfap2 mutants. Forced expression of Tfap2 in i-cells converted them to germ cells. Therefore, Tfap2 is a regulator of germ cell commitment across germ line-sequestering and germ line-nonsequestering animals.


Assuntos
Células-Tronco Adultas/citologia , Gametogênese/fisiologia , Células Germinativas/citologia , Gônadas/embriologia , Hidrozoários/embriologia , Fator de Transcrição AP-2/fisiologia , Células-Tronco Adultas/metabolismo , Animais , Feminino , Gametogênese/genética , Regulação da Expressão Gênica no Desenvolvimento , Gônadas/citologia , Hidrozoários/citologia , Hidrozoários/genética , Masculino , Fator de Transcrição AP-2/genética
5.
Development ; 147(4)2020 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-31988185

RESUMO

Organogenesis requires precise interactions between a developing tissue and its environment. In vertebrates, the developing eye is surrounded by a complex extracellular matrix as well as multiple mesenchymal cell populations. Disruptions to either the matrix or periocular mesenchyme can cause defects in early eye development, yet in many cases the underlying mechanism is unknown. Here, using multidimensional imaging and computational analyses in zebrafish, we establish that cell movements in the developing optic cup require neural crest. Ultrastructural analysis reveals that basement membrane formation around the developing eye is also dependent on neural crest, but only specifically around the retinal pigment epithelium. Neural crest cells produce the extracellular matrix protein nidogen: impairing nidogen function disrupts eye development, and, strikingly, expression of nidogen in the absence of neural crest partially restores optic cup morphogenesis. These results demonstrate that eye formation is regulated in part by extrinsic control of extracellular matrix assembly.This article has an associated 'The people behind the papers' interview.


Assuntos
Membrana Basal/embriologia , Olho/embriologia , Crista Neural/embriologia , Alelos , Animais , Sistemas CRISPR-Cas , Proteínas de Ligação ao Cálcio/fisiologia , Movimento Celular , Eletroforese Capilar , Matriz Extracelular/fisiologia , Proteínas da Matriz Extracelular/fisiologia , Fatores de Transcrição Forkhead/fisiologia , Regulação da Expressão Gênica no Desenvolvimento , Genótipo , Mesoderma/embriologia , Microscopia Eletrônica de Transmissão , Morfogênese , Mutação , Crista Neural/citologia , Organogênese , Retina/embriologia , Epitélio Pigmentado da Retina/embriologia , Transdução de Sinais , Fator de Transcrição AP-2/fisiologia , Peixe-Zebra , Proteínas de Peixe-Zebra/fisiologia
6.
Development ; 146(13)2019 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-31160420

RESUMO

Renal functional units known as nephrons undergo patterning events during development that create a segmental array of cellular compartments with discrete physiological identities. Here, from a forward genetic screen using zebrafish, we report the discovery that transcription factor AP-2 alpha (tfap2a) coordinates a gene regulatory network that activates the terminal differentiation program of distal segments in the pronephros. We found that tfap2a acts downstream of Iroquois homeobox 3b (irx3b), a distal lineage transcription factor, to operate a circuit consisting of tfap2b, irx1a and genes encoding solute transporters that dictate the specialized metabolic functions of distal nephron segments. Interestingly, this regulatory node is distinct from other checkpoints of differentiation, such as polarity establishment and ciliogenesis. Thus, our studies reveal insights into the genetic control of differentiation, where tfap2a is essential for regulating a suite of segment transporter traits at the final tier of zebrafish pronephros ontogeny. These findings have relevance for understanding renal birth defects, as well as efforts to recapitulate nephrogenesis in vivo to facilitate drug discovery and regenerative therapies.


Assuntos
Rim/embriologia , Néfrons/embriologia , Organogênese/genética , Fator de Transcrição AP-2/fisiologia , Proteínas de Peixe-Zebra/fisiologia , Animais , Animais Geneticamente Modificados , Padronização Corporal/genética , Diferenciação Celular/genética , Embrião não Mamífero , Regulação da Expressão Gênica no Desenvolvimento , Genes de Troca/fisiologia , Rim/metabolismo , Néfrons/metabolismo , Pronefro/embriologia , Pronefro/crescimento & desenvolvimento , Pronefro/metabolismo , Fator de Transcrição AP-2/genética , Peixe-Zebra/embriologia , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/genética
7.
Clin Dysmorphol ; 27(3): 71-77, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29683802

RESUMO

In this case study, we investigate a child presenting with patent ductus arteriosus, short philtrum, duck-bill lips, strabismus, a flat nasal bridge, a broad forehead, low-set ears, hypertelorism, up-slanting palpebral fissures, almond-shaped eyes, and hypodontia, all leading to the clinical diagnosis of Char syndrome. Genetic analysis showed heterozygosity for the novel variant c.851T>C, p. Leu284Ser in the TFAP2B gene. Family analysis suggested that at least 20 members, extending six generations back, were affected. All 10 members available for genetic testing were heterozygous for the novel pathogenic variant. Qualitative analysis of the facial dysmorphology in the proband and three of the affected family members using three-dimensional surface scanning showed that the major deviations were observed in the forehead/eyebrow, nose, upper lip, and chin regions with, for example, a flattened nose and reduced height of the upper lip and the face. Furthermore, it is suggested that Char syndrome is associated with disturbances of tooth formation and eruption.


Assuntos
Anormalidades Múltiplas/genética , Permeabilidade do Canal Arterial/genética , Face/anormalidades , Dedos/anormalidades , Fator de Transcrição AP-2/genética , Fator de Transcrição AP-2/fisiologia , Pré-Escolar , Face/fisiologia , Assimetria Facial/genética , Família , Feminino , Dedos/fisiologia , Humanos , Hipertelorismo/genética , Masculino
8.
Development ; 144(1): 33-37, 2017 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-27888190

RESUMO

Epidermis and neural tissues differentiate from the ectoderm in animal embryos. Although epidermal fate is thought to be induced in vertebrate embryos, embryological evidence has indicated that no intercellular interactions during early stages are required for epidermal fate in ascidian embryos. To test this hypothesis, we determined the gene regulatory circuits for epidermal and neural specification in the ascidian embryo. These circuits started with Tfap2-r.b and Sox1/2/3, which are expressed in the ectodermal lineage immediately after zygotic genome activation. Tfap2-r.b expression was diminished in the neural lineages upon activation of fibroblast growth factor signaling, which is known to induce neural fate, and sustained only in the epidermal lineage. Tfap2-r.b specified the epidermal fate cooperatively with Dlx.b, which was activated by Sox1/2/3 This Sox1/2/3-Dlx.b circuit was also required for specification of the anterior neural fate. In the posterior neural lineage, Sox1/2/3 activated Nodal, which is required for specification of the posterior neural fate. Our findings support the hypothesis that the epidermal fate is specified autonomously in ascidian embryos.


Assuntos
Ciona intestinalis/embriologia , Ectoderma/embriologia , Fatores de Transcrição SOXB1/fisiologia , Fator de Transcrição AP-2/fisiologia , Urocordados/embriologia , Animais , Animais Geneticamente Modificados , Padronização Corporal/genética , Diferenciação Celular/genética , Linhagem da Célula/genética , Ciona intestinalis/genética , Ectoderma/metabolismo , Embrião não Mamífero , Epiderme/embriologia , Epiderme/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Transdução de Sinais/genética , Urocordados/genética
9.
Cancer Res ; 76(19): 5857-5869, 2016 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-27480274

RESUMO

RANK expression is associated with poor prognosis in breast cancer even though its therapeutic potential remains unknown. RANKL and its receptor RANK are downstream effectors of the progesterone signaling pathway. However, RANK expression is enriched in hormone receptor negative adenocarcinomas, suggesting additional roles for RANK signaling beyond its hormone-dependent function. Here, to explore the role of RANK signaling once tumors have developed, we use the mouse mammary tumor virus-Polyoma Middle T (MMTV-PyMT), which mimics RANK and RANKL expression patterns seen in human breast adenocarcinomas. Complementary genetic and pharmacologic approaches demonstrate that therapeutic inhibition of RANK signaling drastically reduces the cancer stem cell pool, decreases tumor and metastasis initiation, and enhances sensitivity to chemotherapy. Mechanistically, genome-wide expression analyses show that anti-RANKL therapy promotes lactogenic differentiation of tumor cells. Moreover, RANK signaling in tumor cells negatively regulates the expression of Ap2 transcription factors, and enhances the Wnt agonist Rspo1 and the Sca1-population, enriched in tumor-initiating cells. In addition, we found that expression of TFAP2B and the RANK inhibitor, OPG, in human breast cancer correlate and are associated with relapse-free tumors. These results support the use of RANKL inhibitors to reduce recurrence and metastasis in breast cancer patients based on its ability to induce tumor cell differentiation. Cancer Res; 76(19); 5857-69. ©2016 AACR.


Assuntos
Neoplasias Mamárias Experimentais/prevenção & controle , Recidiva Local de Neoplasia/prevenção & controle , Receptor Ativador de Fator Nuclear kappa-B/antagonistas & inibidores , Transdução de Sinais/fisiologia , Animais , Apoptose/efeitos dos fármacos , Ataxina-1/análise , Diferenciação Celular/efeitos dos fármacos , Docetaxel , Feminino , Humanos , Neoplasias Pulmonares/prevenção & controle , Neoplasias Pulmonares/secundário , Neoplasias Mamárias Experimentais/patologia , Vírus do Tumor Mamário do Camundongo , Camundongos , Camundongos Endogâmicos C57BL , Células-Tronco Neoplásicas/efeitos dos fármacos , Ligante RANK/antagonistas & inibidores , Ligante RANK/farmacologia , Receptor Ativador de Fator Nuclear kappa-B/fisiologia , Taxoides/farmacologia , Fator de Transcrição AP-2/fisiologia
10.
Development ; 143(5): 787-98, 2016 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-26811378

RESUMO

Loss of TFAP2C in mouse leads to developmental defects in the extra-embryonic compartment with lethality at embryonic day (E)7.5. To investigate the requirement of TFAP2C in later placental development, deletion of TFAP2C was induced throughout extra-embryonic ectoderm at E6.5, leading to severe placental abnormalities caused by reduced trophoblast population and resulting in embryonic retardation by E8.5. Deletion of TFAP2C in TPBPA(+) progenitors at E8.5 results in growth arrest of the junctional zone. TFAP2C regulates its target genes Cdkn1a (previously p21) and Dusp6, which are involved in repression of MAPK signaling. Loss of TFAP2C reduces activation of ERK1/2 in the placenta. Downregulation of Akt1 and reduced activation of phosphorylated AKT in the mutant placenta are accompanied by impaired glycogen synthesis. Loss of TFAP2C led to upregulation of imprinted gene H19 and downregulation of Slc38a4 and Ascl2. The placental insufficiency post E16.5 causes fetal growth restriction, with 19% lighter mutant pups. Knockdown of TFAP2C in human trophoblast choriocarcinoma JAr cells inhibited MAPK and AKT signaling. Thus, we present a model where TFAP2C in trophoblasts controls proliferation by repressing Cdkn1a and activating the MAPK pathway, further supporting differentiation of glycogen cells by activating the AKT pathway.


Assuntos
Inibidor de Quinase Dependente de Ciclina p21/fisiologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Proteínas da Gravidez/fisiologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fator de Transcrição AP-2/fisiologia , Animais , Diferenciação Celular , Proliferação de Células , Cruzamentos Genéticos , Inibidor de Quinase Dependente de Ciclina p21/genética , Feminino , Deleção de Genes , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Genótipo , Glicogênio/metabolismo , Hibridização In Situ , Integrases/genética , Integrases/fisiologia , Masculino , Camundongos , Fosforilação , Placenta/metabolismo , Gravidez , Proteínas da Gravidez/genética , Fator de Transcrição AP-2/genética , Transgenes , Trofoblastos/metabolismo
11.
PLoS Genet ; 11(8): e1005464, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26275148

RESUMO

Little is known about how the size of meristem cells is regulated and whether it participates in the control of meristem size in plants. Here, we report our findings on shoebox (shb), a mild gibberellin (GA) deficient rice mutant that has a short root meristem size. Quantitative analysis of cortical cell length and number indicates that shb has shorter, rather than fewer, cells in the root meristem until around the fifth day after sowing, from which the number of cortical cells is also reduced. These defects can be either corrected by exogenous application of bioactive GA or induced in wild-type roots by a dose-dependent inhibitory effect of paclobutrazol on GA biosynthesis, suggesting that GA deficiency is the primary cause of shb mutant phenotypes. SHB encodes an AP2/ERF transcription factor that directly activates transcription of the GA biosynthesis gene KS1. Thus, root meristem size in rice is modulated by SHB-mediated GA biosynthesis that regulates the elongation and proliferation of meristem cells in a developmental stage-specific manner.


Assuntos
Giberelinas/fisiologia , Meristema/crescimento & desenvolvimento , Oryza/crescimento & desenvolvimento , Proteínas de Plantas/fisiologia , Fator de Transcrição AP-2/fisiologia , Sequência de Bases , Sítios de Ligação , Proliferação de Células , Forma Celular , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Meristema/citologia , Meristema/metabolismo , Oryza/citologia , Oryza/metabolismo , Reguladores de Crescimento de Plantas/fisiologia , Raízes de Plantas/citologia , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo
12.
Dev Biol ; 407(1): 75-89, 2015 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-26277217

RESUMO

The species-specific morphology of digits in the tetrapod limb, including the length and number of metacarpal, metatarsal, and phalangeal bones, suggests that a common developmental mechanism for digit formation is modified in a species-specific manner. Here, we examined the function of the AP-2ß transcription factor in regulating digit length in the chicken autopod. Mutations in the gene encoding AP-2ß are associated with Char syndrome, a human autosomal dominant disorder. Char syndrome patients exhibit autopod skeletal defects, including loss of phalanges and shortened fingers, suggestive of a function for AP-2ß in normal digit development. The ectopic expression of two different dominant-negative forms of chick AP-2ß, equivalent to mutant forms associated with human Char syndrome, in the developing chick hindlimb bud resulted in defective digit formation, including reductions in the number and length of phalanges and metatarsals. A detailed analysis of the AP-2ß expression pattern in the limb bud indicated a correlation between the pattern/duration of AP-2ß expression in the limb mesenchyme and digit length in three amniote species, the chicken, mouse and gecko. In addition, we found that AP-2ß expression was downstream of Fgf signals from the apical ectodermal ridge, which is crucial in digit morphogenesis, and that excessive AP-2ß function resulted in dysregulated digit length. Taken together, these results suggest that AP-2ß functions as a novel transcriptional regulator for digit morphogenesis.


Assuntos
Extremidades/embriologia , Fator de Transcrição AP-2/fisiologia , Anormalidades Múltiplas/etiologia , Animais , Proteínas Morfogenéticas Ósseas/fisiologia , Embrião de Galinha , Galinhas , Permeabilidade do Canal Arterial/etiologia , Face/anormalidades , Fatores de Crescimento de Fibroblastos/fisiologia , Dedos/anormalidades , Proteínas Hedgehog/fisiologia , Humanos , Botões de Extremidades/embriologia , Botões de Extremidades/metabolismo , Camundongos , Morfogênese , Transdução de Sinais , Transcrição Gênica
13.
Oncogene ; 34(50): 6105-14, 2015 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-25772240

RESUMO

TFAP2C/AP-2γ influences development of the mammary gland and regulates patterns of gene expression in luminal and HER2-amplified breast cancer. The roles of TFAP2C in mammary gland tumorigenesis and in pathways critical to cancer progression remain poorly understood. To gain greater insight into oncogenic mechanisms regulated by TFAP2C, we examined mammary tumorigenesis in MMTV-Neu transgenic female mice with or without conditional knockout (KO) of Tcfap2c, the mouse homolog of TFAP2C. Loss of Tcfap2c increased the latency of tumorigenesis and tumors that formed demonstrated reduced proliferative index and increased apoptosis. In addition, tumors formed in Tcfap2c KO animals had a significant reduction in Egfr levels without a change in the expression of the Neu oncogene. The MMneu-flAP2C cell line was established from tumor tissue derived from MMTV-Neu/Tcfap2c(L/L) control animals and parallel cell lines with and without expression of Tcfap2c were created by transduction with adenovirus-empty and adenovirus-Cre, respectively. KO of Tcfap2c in vitro reduced activated phosphorylated-Erk, decreased cell viability, repressed tumor growth and was associated with attenuation of Egfr expression. Chromatin immunoprecipitation and direct sequencing and expression analysis confirmed that Egfr was a Tcfap2c target gene in murine, as well as human, mammary carcinoma cells. Furthermore, decreased viability of mammary cancer cells was directly related to Egfr functional blockade. We conclude that TFAP2C regulates tumorigenesis, cell growth and survival in HER2-amplified breast cancer through transcriptional regulation of EGFR. The findings have important implications for targeting the EGFR pathway in breast cancer.


Assuntos
Transformação Celular Neoplásica , Neoplasias Mamárias Experimentais/etiologia , Receptor ErbB-2/fisiologia , Fator de Transcrição AP-2/fisiologia , Animais , Carcinogênese , Sobrevivência Celular , Células Cultivadas , Progressão da Doença , Receptores ErbB/fisiologia , Feminino , Humanos , Neoplasias Mamárias Experimentais/patologia , Vírus do Tumor Mamário do Camundongo/genética , Camundongos , Camundongos Knockout , Regiões Promotoras Genéticas
14.
Oncogene ; 34(4): 436-44, 2015 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-24469049

RESUMO

Molecular subtypes of breast cancer are characterized by distinct patterns of gene expression that are predictive of outcome and response to therapy. The luminal breast cancer subtypes are defined by the expression of estrogen receptor-alpha (ERα)-associated genes, many of which are directly responsive to the transcription factor activator protein 2C (TFAP2C). TFAP2C participates in a gene regulatory network controlling cell growth and differentiation during ectodermal development and regulating ESR1/ERα and other luminal cell-associated genes in breast cancer. TFAP2C has been established as a prognostic factor in human breast cancer, however, its role in the establishment and maintenance of the luminal cell phenotype during carcinogenesis and mammary gland development have remained elusive. Herein, we demonstrate a critical role for TFAP2C in maintaining the luminal phenotype in human breast cancer and in influencing the luminal cell phenotype during normal mammary development. Knockdown of TFAP2C in luminal breast carcinoma cells induced epithelial-mesenchymal transition with morphological and phenotypic changes characterized by a loss of luminal-associated gene expression and a concomitant gain of basal-associated gene expression. Conditional knockout of the mouse homolog of TFAP2C, Tcfap2c, in mouse mammary epithelium driven by MMTV-Cre promoted aberrant growth of the mammary tree leading to a reduction in the CD24(hi)/CD49f(mid) luminal cell population and concomitant gain of the CD24(mid)/CD49f(hi) basal cell population at maturity. Our results establish TFAP2C as a key transcriptional regulator for maintaining the luminal phenotype in human breast carcinoma. Furthermore, Tcfap2c influences development of the luminal cell type during mammary development. The data suggest that TFAP2C has an important role in regulated luminal-specific genes and may be a viable therapeutic target in breast cancer.


Assuntos
Neoplasias da Mama/etiologia , Mama/crescimento & desenvolvimento , Fator de Transcrição AP-2/fisiologia , Animais , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Antígeno CD24/análise , Carcinogênese , Linhagem Celular Tumoral , Transição Epitelial-Mesenquimal , Feminino , Humanos , Receptores de Hialuronatos/análise , Camundongos , Camundongos Knockout , Células-Tronco Neoplásicas/química , Fenótipo , Fator de Transcrição AP-2/análise
15.
Biochemistry (Mosc) ; 79(11): 1226-36, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25540008

RESUMO

The JcERF1 gene, which is related to the ERF family (ethylene responsive factor coding genes), was isolated and characterized from the oil tree Jatropha curcas. The JcERF1 protein contains conserved an AP2/EREBP DNA-binding domain of 58 amino acid residues. The JcERF1 gene could be induced by abscisic acid, high salinity, hormones, and osmotic stress, suggesting that JcERF1 is regulated by certain components of the stress-signaling pathway. The full-length and C-terminus of JcERF1 driven by the GAL4 promoter functioned effectively as a transactivator in yeast, while its N-terminus was completely inactive. Transient expression analysis using a JcERF1-mGFP fusion gene in onion epidermal cells revealed that the JcERF1 protein is targeted to the nucleus. Transgenic tobacco plants carrying CaMV35S::JcERF1 fragments were shown to be much more salt tolerant compared to wild-type plants. Our results indicate that JcERF1 is a new member of the ERF transcription factors family that may play an important role in tolerance to environmental stress.


Assuntos
Jatropha/genética , Nicotiana/genética , Tolerância ao Sal , Fator de Transcrição AP-2/fisiologia , Núcleo Celular/química , Expressão Gênica , Cebolas/genética , Cebolas/fisiologia , Epiderme Vegetal/genética , Epiderme Vegetal/fisiologia , Plantas Geneticamente Modificadas/fisiologia , Nicotiana/fisiologia , Fator de Transcrição AP-2/análise , Fator de Transcrição AP-2/genética
16.
Dev Dyn ; 243(10): 1298-309, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24753151

RESUMO

BACKGROUND: Transcription factors are critical in regulating lens development. The AP-2 family of transcription factors functions in differentiation, cell growth and apoptosis, and in lens and eye development. AP-2α, in particular, is important in early lens development, and when conditionally deleted at the placode stage defective separation of the lens vesicle from the surface ectoderm results. AP-2α's role during later stages of lens development is unknown. To address this, the MLR10-Cre transgene was used to delete AP-2α from the lens epithelium beginning at embryonic day (E) 10.5. RESULTS: The loss of AP-2α after lens vesicle separation resulted in morphological defects beginning at E18.5. By P4, a small highly vacuolated lens with a multilayered epithelium was evident in the MLR10-AP-2α mutants. Epithelial cells appeared elongated and expressed fiber cell specific ßB1 and γ-crystallins. Epithelial cell polarity and lens cell adhesion was disrupted and accompanied by the misexpression of ZO-1, N-Cadherin, and ß-catenin. Cell death was observed in the mutant lens epithelium between postnatal day (P) 14 and P30, and correlated with altered arrangements of cells within the epithelium. CONCLUSIONS: Our findings demonstrate that AP-2α continues to be required after lens vesicle separation to maintain a normal lens epithelial cell phenotype and overall lens integrity and to ensure correct fiber cell differentiation.


Assuntos
Cristalino/fisiologia , Fator de Transcrição AP-2/fisiologia , Animais , Catarata/genética , Adesão Celular/genética , Diferenciação Celular/genética , Polaridade Celular/genética , Embrião de Mamíferos , Células Epiteliais/metabolismo , Células Epiteliais/fisiologia , Epitélio/metabolismo , Epitélio/fisiologia , Regulação da Expressão Gênica no Desenvolvimento , Cristalino/embriologia , Camundongos , Camundongos Transgênicos , Fenótipo
17.
EMBO J ; 33(4): 312-26, 2014 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-24451200

RESUMO

Androgen receptor (AR) binds male sex steroids and mediates physiological androgen actions in target tissues. ChIP-seq analyses of AR-binding events in murine prostate, kidney and epididymis show that in vivo AR cistromes and their respective androgen-dependent transcription programs are highly tissue specific mediating distinct biological pathways. This high order of tissue specificity is achieved by the use of exclusive collaborating factors in the three androgen-responsive tissues. We find two novel collaborating factors for AR signaling in vivo--Hnf4α (hepatocyte nuclear factor 4α) in mouse kidney and AP-2α (activating enhancer binding protein 2α) in mouse epididymis--that define tissue-specific AR recruitment. In mouse prostate, FoxA1 serves for the same purpose. FoxA1, Hnf4α and AP-2α motifs are over-represented within unique AR-binding loci, and the cistromes of these factors show substantial overlap with AR-binding events distinct to each tissue type. These licensing or pioneering factors are constitutively bound to chromatin and guide AR to specific genomic loci upon hormone exposure. Collectively, liganded receptor and its DNA-response elements are required but not sufficient for establishment of tissue-specific transcription programs.


Assuntos
Epididimo/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Fator 3-alfa Nuclear de Hepatócito/fisiologia , Fator 4 Nuclear de Hepatócito/fisiologia , Rim/metabolismo , Próstata/metabolismo , Receptores Androgênicos/metabolismo , Testosterona/farmacologia , Fator de Transcrição AP-2/fisiologia , Animais , Linhagem Celular , Cromatina/metabolismo , Imunoprecipitação da Cromatina , Epididimo/citologia , Perfilação da Expressão Gênica , Masculino , Camundongos , Camundongos Endogâmicos ICR , Orquiectomia , Especificidade de Órgãos , Ligação Proteica , Interferência de RNA , RNA Interferente Pequeno/farmacologia , Proteínas de Ligação a Tacrolimo/biossíntese , Proteínas de Ligação a Tacrolimo/genética , Testosterona/fisiologia , Transcrição Gênica
18.
FEBS Lett ; 588(5): 770-5, 2014 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-24462686

RESUMO

The AP-2δ transcription factor is restricted to a subset of retinal ganglion cells. Overexpression of AP-2δ in chick retina results in induction of polysialylated neural cell adhesion molecule (PSA-NCAM) accompanied by misrouting and bundling of ganglion cell axons. Two polysialyltransferases, ST8SIA2 and ST8SIA4, are responsible for polysialylation of NCAM. Here, we investigate the mechanism driving the increase in PSA-NCAM observed upon AP-2δ overexpression. We show that ST8SIA2 is induced by AP-2δ overexpression in chick retina. We use chromatin immunoprecipitation and gel shift assays to demonstrate direct interaction between AP-2δ and the ST8SIA2 promoter. We propose that up-regulation of ST8SIA2 upon AP-2δ overexpression in retina increases ectopic polysialylation of NCAM which in turn causes premature bundling of axons and alters axonal response to guidance cues.


Assuntos
Proteínas Aviárias/genética , Retina/enzimologia , Sialiltransferases/genética , Fator de Transcrição AP-2/fisiologia , Animais , Proteínas Aviárias/metabolismo , Axônios/enzimologia , Sequência de Bases , Sítios de Ligação , Embrião de Galinha , Regulação Enzimológica da Expressão Gênica , Regiões Promotoras Genéticas , Ligação Proteica , Retina/citologia , Células Ganglionares da Retina/enzimologia , Sialiltransferases/metabolismo
19.
Cancer Prev Res (Phila) ; 7(2): 266-77, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24335623

RESUMO

TFAP2A is a transcription factor that orchestrates a variety of cell processes, including cell growth and tissue differentiation. However, the regulation of TFAP2A in human nasopharyngeal carcinoma tumorigenesis and its precise mechanism of action remain largely unknown. In this study, we investigated the biologic role and clinical significance of TFAP2A in nasopharyngeal carcinoma growth and progression and identified the underlying molecular mechanisms. We found that TFAP2A was highly expressed in various nasopharyngeal carcinoma cell lines and tumor tissue specimens and was significantly correlated with hypoxia-inducible factor-1α (HIF-1α) expression. A positive correlation of TFAP2A overexpression with advanced tumor stage, local invasion, clinical progression, and poor prognosis of patients with nasopharyngeal carcinomas were also observed. Moreover, we found that knockdown of TFAP2A expression by siRNA significantly inhibited tumor cell growth in nasopharyngeal carcinoma cell lines and in a subcutaneous xenograft mouse model by targeting the HIF-1α-mediated VEGF/pigment epithelium-derived factor (PEDF) signaling pathway. Treatment of nasopharyngeal carcinoma cells with TFAP2A siRNA dramatically inhibited the expression and the release of VEGF protein but did not change the level of PEDF protein, resulting in a significant reduction of the ratio of VEGF/PEDF. Pretreatment with a HIF-1α siRNA did not significantly change the TFAP2A siRNA-mediated inhibition in cell viability. Our results indicate that TFAP2A regulates nasopharyngeal carcinoma growth and survival through the modulation of the HIF-1α-mediated VEGF/PEDF signaling pathway, and suggest that TFAP2A could be a potential prognostic biomarker and therapeutic target for nasopharyngeal carcinoma treatment.


Assuntos
Proliferação de Células , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Neoplasias Nasofaríngeas/patologia , Fator de Transcrição AP-2/fisiologia , Adulto , Idoso , Animais , Carcinoma , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Masculino , Camundongos , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/genética , RNA Interferente Pequeno/farmacologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Fator de Transcrição AP-2/antagonistas & inibidores , Ensaios Antitumorais Modelo de Xenoenxerto , Adulto Jovem
20.
Neuropsychobiology ; 68(2): 79-90, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23881096

RESUMO

BACKGROUND: The transcription factor AP-2ß has been shown to impact clinical and neuropsychological properties. Apparently, it regulates the transcription of genes that code for molecules which are part of the catecholaminergic transmission system. This investigation focuses on possible effects of the transcription factor AP-2ß intron 2 polymorphism on cognitive performance parameters. METHODS: This hypothesis-driven investigation examined the effects and interactions of the transcription factor AP-2ß intron 2 polymorphism, the Val158Met catechol-O-methyltransferase (COMT) polymorphism, and the variable number of tandem repeat polymorphism of monoamine oxidase A (MAOA) on cognitive performance parameters within a group of 200 healthy women (age: mean ± SD, 23.93 ± 3.33 years). RESULTS: The AP-2ß polymorphism significantly influenced cognitive performance (in particular, the Trail Making Test part B), whereas the MAOA and COMT polymorphisms did not. However, there was an interaction effect of the AP-2ß × MAOA × COMT genotypes on the decision bias ß of the degraded-stimulus version of the continuous performance task. Only the Val158Met COMT polymorphism showed an influence on personality questionnaires (openness and self-transcendence; NEO Five-Factor Inventory, Temperament and Character Inventory). CONCLUSION: The transcription factor AP-2ß intron 2 polymorphism had more influence on cognition than the MAOA and COMT polymorphisms. Possibly, the AP-2ß genotype might influence cognition through pathways other than those that regulate MAOA and COMT transcription. Interactions of transcription factor AP-2ß, COMT, and MAOA polymorphisms suggest higher leverage effects of transcription factor AP-2ß in subjects with high dopamine availability.


Assuntos
Catecol O-Metiltransferase/fisiologia , Cognição/fisiologia , Monoaminoxidase/fisiologia , Fator de Transcrição AP-2/fisiologia , Adulto , Catecol O-Metiltransferase/genética , Feminino , Voluntários Saudáveis , Humanos , Monoaminoxidase/genética , Testes Neuropsicológicos , Inventário de Personalidade , Polimorfismo Genético , Fator de Transcrição AP-2/genética
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