Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 25
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Int J Mol Sci ; 22(14)2021 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-34299284

RESUMO

Forkhead box E1 (FOXE1) is a lineage-restricted transcription factor involved in thyroid cancer susceptibility. Cancer-associated polymorphisms map in regulatory regions, thus affecting the extent of gene expression. We have recently shown that genetic reduction of FOXE1 dosage modifies multiple thyroid cancer phenotypes. To identify relevant effectors playing roles in thyroid cancer development, here we analyse FOXE1-induced transcriptional alterations in thyroid cells that do not express endogenous FOXE1. Expression of FOXE1 elicits cell migration, while transcriptome analysis reveals that several immune cells-related categories are highly enriched in differentially expressed genes, including several upregulated chemokines involved in macrophage recruitment. Accordingly, FOXE1-expressing cells induce chemotaxis of co-cultured monocytes. We then asked if FOXE1 was able to regulate macrophage infiltration in thyroid cancers in vivo by using a mouse model of cancer, either wild type or with only one functional FOXE1 allele. Expression of the same set of chemokines directly correlates with FOXE1 dosage, and pro-tumourigenic M2 macrophage infiltration is decreased in tumours with reduced FOXE1. These data establish a novel link between FOXE1 and macrophages recruitment in the thyroid cancer microenvironment, highlighting an unsuspected function of this gene in the crosstalk between neoplastic and immune cells that shape tumour development and progression.


Assuntos
Quimiotaxia/fisiologia , Fatores de Transcrição Forkhead/genética , Macrófagos/patologia , Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/patologia , Animais , Células Cultivadas , Modelos Animais de Doenças , Fatores de Transcrição Forkhead/biossíntese , Fatores de Transcrição Forkhead/metabolismo , Humanos , Técnicas In Vitro , Macrófagos/citologia , Camundongos , Camundongos Knockout , Ratos , Ratos Endogâmicos F344 , Glândula Tireoide/metabolismo , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/metabolismo
4.
Int J Mol Sci ; 22(1)2020 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-33375029

RESUMO

The transcription factor Forkhead box E1 (FOXE1) is a key player in thyroid development and function and has been identified by genome-wide association studies as a susceptibility gene for papillary thyroid cancer. Several cancer-associated polymorphisms fall into gene regulatory regions and are likely to affect FOXE1 expression levels. However, the possibility that changes in FOXE1 expression modulate thyroid cancer development has not been investigated. Here, we describe the effects of FOXE1 gene dosage reduction on cancer phenotype in vivo. Mice heterozygous for FOXE1 null allele (FOXE1+/-) were crossed with a BRAFV600E-inducible cancer model to develop thyroid cancer in either a FOXE1+/+ or FOXE1+/- genetic background. In FOXE1+/+ mice, cancer histological features are quite similar to that of human high-grade papillary thyroid carcinomas, while cancers developed with reduced FOXE1 gene dosage maintain morphological features resembling less malignant thyroid cancers, showing reduced proliferation index and increased apoptosis as well. Such cancers, however, appear severely undifferentiated, indicating that FOXE1 levels affect thyroid differentiation during neoplastic transformation. These results show that FOXE1 dosage exerts pleiotropic effects on thyroid cancer phenotype by affecting histology and regulating key markers of tumor differentiation and progression, thus suggesting the possibility that FOXE1 could behave as lineage-specific oncogene in follicular cell-derived thyroid cancer.


Assuntos
Fatores de Transcrição Forkhead/genética , Regulação Neoplásica da Expressão Gênica , Câncer Papilífero da Tireoide/genética , Glândula Tireoide/metabolismo , Neoplasias da Glândula Tireoide/genética , Animais , Apoptose/genética , Diferenciação Celular/genética , Proliferação de Células/genética , Transformação Celular Neoplásica/genética , Fatores de Transcrição Forkhead/metabolismo , Pleiotropia Genética , Humanos , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas B-raf/metabolismo , Câncer Papilífero da Tireoide/metabolismo , Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/metabolismo
5.
Sci Rep ; 10(1): 7057, 2020 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-32341372

RESUMO

We have recently identified and characterized two pseudogenes (HMGA1P6 and HMGA1P7) of the HMGA1 gene, which has a critical role in malignant cell transformation and cancer progression. HMGA1P6 and HMGAP17 act as microRNA decoy for HMGA1 and other cancer-related genes upregulating their protein levels. We have previously shown that they are upregulated in several human carcinomas, and their expression positively correlates with a poor prognosis and an advanced cancer stage. To evaluate in vivo oncogenic activity of HMGA1 pseudogenes, we have generated a HMGA1P7 transgenic mouse line overexpressing this pseudogene. By a mean age of 12 months, about 50% of the transgenic mice developed splenomegaly and accumulation of lymphoid cells in several body compartments. For these mice FACS and immunohistochemical analyses suggested the diagnosis of B-cell lymphoma that was further supported by clonality analyses and RNA expression profile of the pathological tissues of the HMGA1P7 transgenic tissues. Therefore, these results clearly demonstrate the oncogenic activity of HMGA1 pseudogenes in vivo.


Assuntos
Proteína HMGA1a/metabolismo , Linfoma de Células B/metabolismo , Animais , Citometria de Fluxo , Proteína HMGA1a/genética , Imuno-Histoquímica , Linfócitos/metabolismo , Linfoma de Células B/genética , Camundongos , Camundongos Transgênicos , Células NIH 3T3 , Pseudogenes/genética , RNA-Seq
6.
Cell Death Dis ; 10(10): 747, 2019 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-31582725

RESUMO

The serine-threonine kinase homeodomain-interacting protein kinase 2 (HIPK2) modulates important cellular functions during development, acting as a signal integrator of a wide variety of stress signals, and as a regulator of transcription factors and cofactors. We have previously demonstrated that HIPK2 binds and phosphorylates High-Mobility Group A1 (HMGA1), an architectural chromatinic protein ubiquitously expressed in embryonic tissues, decreasing its binding affinity to DNA. To better define the functional role of HIPK2 and HMGA1 interaction in vivo, we generated mice in which both genes are disrupted. About 50% of these Hmga1/Hipk2 double knock-out (DKO) mice die within 12 h of life (P1) for respiratory failure. The DKO mice present an altered lung morphology, likely owing to a drastic reduction in the expression of surfactant proteins, that are required for lung development. Consistently, we report that both HMGA1 and HIPK2 proteins positively regulate the transcriptional activity of the genes encoding the surfactant proteins. Moreover, these mice display an altered expression of thyroid differentiation markers, reasonably because of a drastic reduction in the expression of the thyroid-specific transcription factors PAX8 and FOXE1, which we demonstrate here to be positively regulated by HMGA1 and HIPK2. Therefore, these data indicate a critical role of HIPK2/HMGA1 cooperation in lung and thyroid development and function, suggesting the potential involvement of their impairment in the pathogenesis of human lung and thyroid diseases.


Assuntos
Proteína HMGA1a/genética , Proteínas Serina-Treonina Quinases/genética , Doenças Respiratórias/genética , Glândula Tireoide/anormalidades , Animais , Animais Recém-Nascidos , Desenvolvimento Embrionário , Deleção de Genes , Regulação da Expressão Gênica , Proteína HMGA1a/metabolismo , Células HeLa , Humanos , Pulmão/metabolismo , Pulmão/patologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Associadas a Surfactantes Pulmonares , Doenças Respiratórias/patologia , Glândula Tireoide/embriologia , Glândula Tireoide/patologia
7.
Cancer Res ; 79(22): 5746-5757, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31558562

RESUMO

Klhl14-AS is a long noncoding RNA expressed since early specification of thyroid bud and is the most enriched gene in the mouse thyroid primordium at E10.5. Here, we studied its involvement in thyroid carcinogenesis by analyzing its expression in cancer tissues and different models of neoplastic transformation. Compared with normal thyroid tissue and cells, Klhl14-AS was significantly downregulated in human thyroid carcinoma tissue specimens, particularly the anaplastic histotype, thyroid cancer cell lines, and rodent models of thyroid cancer. Downregulating the expression of Klhl14-AS in normal thyroid cells decreased the expression of thyroid differentiation markers and cell death and increased cell viability. These effects were mediated by the binding of Klhl14-AS to two miRNAs, Mir182-5p and Mir20a-5p, which silenced Pax8 and Bcl2, both essential players of thyroid differentiation. MIR182-5p and MIR20a-5p were upregulated in human thyroid cancer and thyroid cancer experimental models and their effects on Pax8 and Bcl2 were rescued by Klhl14-AS overexpression, confirming Klhl14-AS as a ceRNA for both Pax8 and Bcl2. This work connects deregulation of differentiation with increased proliferation and survival in thyroid neoplastic cells and highlights a novel ceRNA circuitry involving key regulators of thyroid physiology. SIGNIFICANCE: This study describes a new ceRNA with potential tumor suppression activity and helps us better understand the regulatory mechanisms during thyroid differentiation and carcinogenesis.


Assuntos
Carcinogênese/genética , Fator de Transcrição PAX8/genética , Proteínas Proto-Oncogênicas c-bcl-2/genética , RNA Longo não Codificante/genética , Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/patologia , Animais , Biomarcadores Tumorais/genética , Carcinogênese/patologia , Morte Celular/genética , Diferenciação Celular/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Sobrevivência Celular/genética , Regulação para Baixo/genética , Regulação Neoplásica da Expressão Gênica/genética , Células HeLa , Humanos , Camundongos , Camundongos Transgênicos , MicroRNAs/genética , Regulação para Cima/genética
8.
Cancers (Basel) ; 11(6)2019 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-31181813

RESUMO

Background: We have recently reported the downregulation of the Metallophosphoesterase-domain-containing protein 2 (MPPED2) gene and its cognate long non-coding RNA, MPPED2-AS1, in papillary thyroid carcinomas. Functional studies supported a tumor suppressor role of both these genes in thyroid carcinogenesis. We then decided to investigate their role in breast carcinogenesis. Methods: In order to verify MPPED2 expression, 45 human breast carcinoma samples have been investigated by quantitative real-time polymerase chain reaction (qRT-PCR). Then, MPPED2 has been transfected in several human breast carcinoma cell lines, analyzing its role in cell proliferation, migration and invasion. To study the regulation of MPPED2 expression the methylation of its promoter was investigated by targeted bisulfite sequencing. Results: MPPED2 expression was decreased in breast cancer samples, and this was confirmed by the analysis of data available in The Cancer Genome Atlas (TCGA). Interestingly, the hypermethylation of MPPED2 promoter likely accounted for its downregulation in breast cancer. Additionally, MPPED2-AS1 was also found downregulated in breast cancer tissues and, intriguingly, its expression decreased the hypermethylation of the MPPED2 promoter by inhibiting DNA methyltransferase 1 (DNMT1). Furthermore, the restoration of MPPED2 expression reduced cell proliferation, migration and invasion capability of breast carcinoma cell lines. Conclusion: Taken together, these results propose MPPED2 downregulation as a critical event in breast carcinogenesis.

9.
Artigo em Inglês | MEDLINE | ID: mdl-30621213

RESUMO

Epidemiological and experimental studies emphasize the link between environmental chemicals exposure and thyroid cancer. However, this association is strongly debated and the mechanisms of action of environmental thyroid carcinogens still need to be identified. The analysis of in vitro transcriptomic data developed to investigate the effects of chlorpyrifos on immortalized thyrocytes highlighted the impaired expression of genes involved in endodermal carcinogenesis. This endodermal carcinogenic gene-network (ECGN, including Zfp36l2, Dmbt1, Ddit4), was validated in cellular and mouse models of thyroid carcinogenesis, characterized by the constitutive activation of the mitogen-activated protein kinase (MAPK) pathway and in immortalized thyrocytes exposed to tetrachlorodibenzo-p-dioxin (TCDD) and chlorpyrifos (CPF). The mRNA levels of Zfp36l2, Dmbt1 and Ddit4 were increased in models characterized by MAPK activation or following TCDD exposure, whereas they were inhibited by CPF exposure. Overall, the ECGN transcripts identify a novel gene-regulatory network associated with thyroid carcinogenesis promoted by genetic mutation or by environmental carcinogens. The latter have opposite effects on the modulation of the ECGN transcripts according to their mechanisms of action in promoting carcinogenesis. Therefore, the analyses of ECGN might be helpful in discriminating compounds that promote cellular survival associated or not to proliferation of thyrocytes.


Assuntos
Redes Reguladoras de Genes , Neoplasias da Glândula Tireoide/genética , Animais , Carcinogênese , Carcinógenos/toxicidade , Linhagem Celular , Clorpirifos/toxicidade , Feminino , Troca Materno-Fetal , Camundongos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Dibenzodioxinas Policloradas/toxicidade , Gravidez , Ratos , Receptores de Superfície Celular/genética , Células Epiteliais da Tireoide/efeitos dos fármacos , Células Epiteliais da Tireoide/metabolismo , Fatores de Transcrição/genética , Tristetraprolina/genética
10.
Int J Genomics ; 2017: 9769171, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29082235

RESUMO

lncRNAs are acquiring increasing relevance as regulators in a wide spectrum of biological processes. The extreme heterogeneity in the mechanisms of action of these molecules, however, makes them very difficult to study, especially regarding their molecular function. A novel lncRNA has been recently identified as the most enriched transcript in mouse developing thyroid. Due to its genomic localization antisense to the protein-encoding Klhl14 gene, we named it Klhl14-AS. In this paper, we highlight that mouse Klhl14-AS produces at least five splicing variants, some of which have not been previously described. Klhl14-AS is expressed with a peculiar pattern, characterized by diverse relative abundance of its isoforms in different mouse tissues. We examine the whole expression level of Klhl14-AS in a panel of adult mouse tissues, showing that it is expressed in the thyroid, lung, kidney, testis, ovary, brain, and spleen, although at different levels. In situ hybridization analysis reveals that, in the context of each organ, Klhl14-AS shows a cell type-specific expression. Interestingly, databases report a similar expression profile for human Klhl14-AS. Our observations suggest that this lncRNA could play cell type-specific roles in several organs and pave the way for functional characterization of this gene in appropriate biological contexts.

11.
Cell Cycle ; 16(23): 2282-2289, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28933615

RESUMO

DICER1 plays a central role in the biogenesis of microRNAs and it is important for normal development. Altered microRNA expression and DICER1 dysregulation have been described in several types of tumors, including thyroid carcinomas. Recently, our group identified a new somatic mutation (c.5438A>G; E1813G) within DICER1 gene of an unknown function. Herein, we show that DICER1 is overexpressed, at mRNA level, in a significant-relative number of papillary (70%) and anaplastic (42%) thyroid carcinoma samples, whereas is drastically downregulated in all the analyzed human thyroid carcinoma cell lines (TPC-1, BCPAP, FRO and 8505c) in comparison with normal thyroid tissue samples. Conversely, DICER1 is downregulated, at protein level, in PTC in comparison with normal thyroid tissues. Our data also reveals that DICER1 overexpression positively regulates thyroid cell proliferation, whereas its silencing impairs thyroid cell differentiation. The expression of DICER1 gene mutation (c.5438A>G; E1813G) negatively affects the microRNA machinery and cell proliferation as well as upregulates DICER1 protein levels of thyroid cells but has no impact on thyroid differentiation. In conclusion, DICER1 protein is downregulated in papillary thyroid carcinomas and affects thyroid proliferation and differentiation, while DICER1 gene mutation (c.5438A>G; E1813G) compromises the DICER1 wild-type-mediated microRNA processing and cell proliferation.


Assuntos
Diferenciação Celular , Proliferação de Células , RNA Helicases DEAD-box/metabolismo , Ribonuclease III/metabolismo , Neoplasias da Glândula Tireoide/patologia , Carcinoma/metabolismo , Carcinoma/patologia , Carcinoma Papilar/metabolismo , Carcinoma Papilar/patologia , Linhagem Celular Tumoral , RNA Helicases DEAD-box/antagonistas & inibidores , RNA Helicases DEAD-box/genética , Regulação para Baixo , Humanos , MicroRNAs/metabolismo , Mutagênese Sítio-Dirigida , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Ribonuclease III/antagonistas & inibidores , Ribonuclease III/genética , Glândula Tireoide/metabolismo , Neoplasias da Glândula Tireoide/metabolismo
12.
Sci Rep ; 6: 25268, 2016 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-27125250

RESUMO

The regulatory transcriptional factor PATZ1 is constantly downregulated in human thyroid cancer where it acts as a tumour suppressor by targeting p53-dependent genes involved in Epithelial-Mesenchymal Transition and cell migration. The aim of the present work was to elucidate the upstream signalling mechanisms regulating PATZ1 expression in thyroid cancer cells. The bioinformatics search for microRNAs able to potentially target PATZ1 led to the identification of several miRNAs. Among them we focused on the miR-29b since it was found upregulated in rat thyroid differentiated cells transformed by the Ha-Ras oncogene towards a high proliferating and high migratory phenotype resembling that of anaplastic carcinomas. Functional assays confirmed PATZ1 as a target of miR-29b, and, consistently, an inverse correlation between miR-29b and PATZ1 protein levels was found upon induction of Ha-Ras oncogene expression in these cells. Interestingly, restoration of PATZ1 expression in rat thyroid cells stably expressing the Ha-Ras oncogene decreased cell proliferation and migration, indicating a key role of PATZ1 in Ras-driven thyroid transformation. Together, these results suggest a novel mechanism regulating PATZ1 expression based on the upregulation of miR-29b expression induced by Ras oncogene.


Assuntos
MicroRNAs/metabolismo , Proteínas Oncogênicas/metabolismo , Fatores de Transcrição/biossíntese , Proteínas ras/metabolismo , Animais , Linhagem Celular , Movimento Celular , Proliferação de Células , Ratos
13.
BMC Mol Biol ; 17: 11, 2016 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-27090781

RESUMO

BACKGROUND: Non-coding RNAs have gained increasing attention during the last decade. The first large group of non-coding RNAs to be characterized systematically starting at the beginning of the 21st century were small oligonucleotides--the so-called microRNAs (miRNAs). By now we have learnt that microRNAs are indispensable for most biological processes including organogenesis and maintenance of organ structure and function. The role of microRNAs has been studied extensively in the development of a number of organs, so far most studies focussed on e.g. the heart or the brain whilst the role of microRNAs in the development and maintenance of complex epithelial organs is less well understood. Furthermore most analyses regarding microRNA function in epithelial organs employed conditional knockout mouse models of the RNAse III Dicer to abrogate microRNA biogenesis. However, there is increasing evidence for Dicer to have multiple functions independent from microRNA maturation. Therefore Dicer independent models are needed to gain further insight into the complex biology of miRNA dependent processes. RESULTS: Here we analyze the contribution of microRNA-dependent transcriptional control in Pax8-expressing epithelial cells. Pax8 is a transcription factor that is crucial to the development of epithelial organs. The miRNA machinery was disrupted by crossing conditional DiGeorge syndrome critical region 8 (Dgcr8) fl/fl mice to Pax8Cre mice. The Dgcr8/Drosha complex processes pri-miRNAs in the nucleus before they are exported as pre-miRNAs for further maturation by Dicer in the cytoplasm. Dgcr8 fl/fl; Pax8Cre+ knockout mice died prematurely, developed massive hypothyroidism and end stage renal disease due to a loss of miRNAs in Pax8 expressing tissue. CONCLUSION: Pax8Cre-mediated conditional loss of DiGeorge syndrome critical region 8 (Dgcr8), an essential component of the nuclear machinery that is required for microRNA biogenesis, resulted in severe hypothyroidism, massively reduced body weight and ultimately led to renal failure and death of the animals. These data provide further insight into the importance of miRNAs in organ homeostasis using a Dicer independent model.


Assuntos
Expressão Gênica , Predisposição Genética para Doença , Hipotireoidismo/genética , Falência Renal Crônica/genética , MicroRNAs/genética , Fatores de Transcrição Box Pareados/genética , Animais , Apoptose/genética , Proliferação de Células/genética , Modelos Animais de Doenças , Feminino , Hipotireoidismo/patologia , Rim/metabolismo , Rim/patologia , Falência Renal Crônica/patologia , Masculino , Camundongos , Camundongos Knockout , Fator de Transcrição PAX8 , Fenótipo
14.
Cancer Cell Int ; 15: 113, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26664298

RESUMO

BACKGROUND: Thyroid-derived cell models are commonly used to investigate the characteristics of thyroid cancers. It is noteworthy that each in vitro single cell model system imitates only a few characteristics of thyroid cancer depending on e.g. source of cells or oncogene used to transform the cells. METHODS: In the current work we utilized rat thyroid cancer cell models to determine their clinical relevance in redox gene studies by comparing in vitro expression data to thyroid Oncomine microarray database. To survey the cell lines we analyzed mRNA expression of genes that produce superoxide anion (nox family), genes that catalyze destruction of superoxide anion to hydrogen peroxide (sod family), and genes that remove hydrogen peroxide from cellular environment (catalase, gpx family and prdx family). RESULTS: Based on the current results, rat thyroid PC Cl3, PC PTC1, PC E1A, or FRLT5 cell models can be used to study NOX2, NOX4, SOD2, SOD3, CATALASE, GPX1, GPX2, GPX5, PRDX2, and PRDX3 gene expression and function. CONCLUSIONS: Redox gene expression in rat originated single cell model systems used to study human thyroid carcinogenesis corresponds only partly with human redox gene expression, which may be caused by differences in redox gene activation stimulus. The data suggest careful estimation of the data observed in rat thyroid in vitro models.

15.
Biomed Res Int ; 2015: 780409, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26550576

RESUMO

Extracellular superoxide dismutase (SOD3) is a secreted enzyme that uses superoxide anion as a substrate in a dismutase reaction that results in the formation of hydrogen peroxide. Both of these reactive oxygen species affect growth signaling in cells. Although SOD3 has growth-supporting characteristics, the expression of SOD3 is downregulated in epithelial cancer cells. In the current work, we studied the mechanisms regulating SOD3 expression in vitro using thyroid cell models representing different stages of thyroid cancer. We demonstrate that a low level of RAS activation increases SOD3 mRNA synthesis that then gradually decreases with increasing levels of RAS activation and the decreasing degree of differentiation of the cancer cells. Our data indicate that SOD3 regulation can be divided into two classes. The first class involves RAS-driven reversible regulation of SOD3 expression that can be mediated by the following mechanisms: RAS GTPase regulatory genes that are responsible for SOD3 self-regulation; RAS-stimulated p38 MAPK activation; and RAS-activated increased expression of the mir21 microRNA, which inversely correlates with sod3 mRNA expression. The second class involves permanent silencing of SOD3 mediated by epigenetic DNA methylation in cells that represent more advanced cancers. Therefore, the work suggests that SOD3 belongs to the group of ras oncogene-silenced genes.


Assuntos
Carcinogênese/genética , Carcinogênese/metabolismo , Genes ras/genética , Superóxido Dismutase/metabolismo , Neoplasias da Glândula Tireoide/enzimologia , Neoplasias da Glândula Tireoide/genética , Animais , Linhagem Celular , Líquido Extracelular/metabolismo , Inativação Gênica , Humanos , Ratos , Superóxido Dismutase/genética , Glândula Tireoide
16.
PLoS One ; 10(3): e0119142, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25799508

RESUMO

Dicer is a crucial enzyme for the maturation of miRNAs. Mutations in the Dicer gene are highly associated with Pleuro Pulmonary Blastoma-Family Dysplasia Syndrome (PPB-FDS, OMIM 601200), recently proposed to be renamed Dicer syndrome. Aside from the pulmonary phenotype (blastoma), renal nephroma and thyroid goiter are frequently part of Dicer syndrome. To investigate the renal phenotype, conditional knockout (cKO) mice for Dicer in Pax8 expressing cells were generated. Dicer cKO mice progressively develop a glomerulocystic phenotype coupled with urinary concentration impairment, proteinuria and severe renal failure. Higher cellular turnover of the parietal cells of Bowman's capsule precedes the development of the cysts and the primary cilium progressively disappears with cyst-enlargement. Upregulation of GSK3ß precedes the development of the glomerulocystic phenotype. Downregulation of ß-catenin in the renal cortex and its cytosolic removal in the cells lining the cysts may be associated with observed accumulation of GSK3ß. Alterations of ß-catenin regulating pathways could promote cystic degeneration as in other models. Thus, miRNAs are fundamental in preserving renal morphology and function. Alteration of the GSK3ß/ß-catenin pathway could be a crucial mechanism linking miRNA dysregulation and the development of a glomerulocystic disease.


Assuntos
RNA Helicases DEAD-box/genética , Quinase 3 da Glicogênio Sintase/metabolismo , Doenças Renais Císticas/genética , Rim/patologia , Ribonuclease III/genética , beta Catenina/metabolismo , Animais , RNA Helicases DEAD-box/metabolismo , Regulação da Expressão Gênica , Glicogênio Sintase Quinase 3 beta , Rim/metabolismo , Doenças Renais Císticas/patologia , Camundongos , Camundongos Knockout , Fator de Transcrição PAX8 , Fatores de Transcrição Box Pareados/metabolismo , Ribonuclease III/metabolismo , Transdução de Sinais
17.
PLoS One ; 6(11): e27648, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22132122

RESUMO

Dicer is a type III ribonuclease required for the biogenesis of microRNAs (miRNAs), a class of small non-coding RNAs regulating gene expression at the post-transcriptional level. To explore the functional role of miRNAs in thyroid gland function, we generated a thyrocyte-specific Dicer conditional knockout mouse. Here we show that development and early differentiation of the thyroid gland are not affected by the absence of Dicer, while severe hypothyroidism gradually develops after birth, leading to reduced body weight and shortened life span. Histological and molecular characterization of knockout mice reveals a dramatic loss of the thyroid gland follicular architecture associated with functional aberrations and down-regulation of several differentiation markers. The data presented in this study show for the first time that an intact miRNAs processing machinery is essential for thyroid physiology, suggesting that deregulation of specific miRNAs could be also involved in human thyroid dysfunctions.


Assuntos
MicroRNAs/metabolismo , Processamento Pós-Transcricional do RNA , Ribonuclease III/metabolismo , Glândula Tireoide/enzimologia , Animais , Animais Recém-Nascidos , Biomarcadores/metabolismo , Moléculas de Adesão Celular/metabolismo , Diferenciação Celular , Embrião de Mamíferos/enzimologia , Embrião de Mamíferos/patologia , Ativação Enzimática , Imunofluorescência , Humanos , Hipotireoidismo/enzimologia , Hipotireoidismo/patologia , Camundongos , Camundongos Knockout , Morfogênese , Células Oxífilas/metabolismo , Células Oxífilas/patologia , Glândula Tireoide/crescimento & desenvolvimento , Glândula Tireoide/patologia
18.
Adv Exp Med Biol ; 604: 17-46, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17695719

RESUMO

Endogenous small RNAs (miRNAs) regulate gene expression by mechanisms conserved across metazoans. While the number of verified human miRNAs is still expanding, only few have been functionally annotated. To perform genetic screens for novel functions of miRNAs, we developed a library of vectors expressing the majority of cloned human miRNAs and created corresponding DNA barcode arrays. In a screen for miRNAs that cooperate with oncogenes in cellular transformation, we identified miR-372 and miR-373, each permitting proliferation and tumorigenesis of primary human cells that harbor both oncogenic RAS and active wild-type p53. These miRNAs neutralize p53-mediated CDK inhibition, possibly through direct inhibition of the expression of the tumorsuppressor LATS2. We provide evidence that these miRNAs are potential novel oncogenes participating in the development of human testicular germ cell tumors by numbing the p53 pathway, thus allowing tumorigenic growth in the presence of wild-type p53.


Assuntos
Regulação da Expressão Gênica , Técnicas Genéticas , MicroRNAs/genética , Neoplasias Embrionárias de Células Germinativas/genética , Neoplasias Testiculares/genética , Animais , Sequência de Bases , Linhagem Celular Tumoral , Transformação Celular Neoplásica , Testes Genéticos/métodos , Humanos , Masculino , Camundongos , Camundongos Nus , MicroRNAs/química , Dados de Sequência Molecular , Transplante de Neoplasias , Proteínas Serina-Treonina Quinases/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Proteínas ras/metabolismo
19.
Cell ; 129(7): 1401-14, 2007 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-17604727

RESUMO

MicroRNAs (miRNAs) are small noncoding regulatory RNAs that reduce stability and/or translation of fully or partially sequence-complementary target mRNAs. In order to identify miRNAs and to assess their expression patterns, we sequenced over 250 small RNA libraries from 26 different organ systems and cell types of human and rodents that were enriched in neuronal as well as normal and malignant hematopoietic cells and tissues. We present expression profiles derived from clone count data and provide computational tools for their analysis. Unexpectedly, a relatively small set of miRNAs, many of which are ubiquitously expressed, account for most of the differences in miRNA profiles between cell lineages and tissues. This broad survey also provides detailed and accurate information about mature sequences, precursors, genome locations, maturation processes, inferred transcriptional units, and conservation patterns. We also propose a subclassification scheme for miRNAs for assisting future experimental and computational functional analyses.


Assuntos
Sequência de Bases/genética , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica/genética , Biblioteca Gênica , MicroRNAs/genética , Animais , Linhagem da Célula/genética , Sequência Conservada/genética , Neoplasias Hematológicas/genética , Células-Tronco Hematopoéticas/metabolismo , Humanos , Camundongos , Dados de Sequência Molecular , Filogenia , RNA Mensageiro/genética , Ratos , Homologia de Sequência do Ácido Nucleico
20.
Cancer Cell ; 11(2): 191-205, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17292829

RESUMO

p38alpha is a stress-activated protein kinase that negatively regulates malignant transformation induced by oncogenic H-Ras, although the mechanisms involved are not fully understood. Here, we show that p38alpha is not a general inhibitor of oncogenic signaling, but that it specifically modulates transformation induced by oncogenes that produce reactive oxygen species (ROS). This inhibitory effect is due to the ROS-induced activation of p38alpha early in the process of transformation, which induces apoptosis and prevents the accumulation of ROS and their carcinogenic effects. Accordingly, highly tumorigenic cancer cell lines have developed a mechanism to uncouple p38alpha activation from ROS production. Our results indicate that oxidative stress sensing plays a key role in the inhibition of tumor initiation by p38alpha.


Assuntos
Transformação Celular Neoplásica , Proteína Quinase 14 Ativada por Mitógeno/fisiologia , Neoplasias/metabolismo , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Sequência de Aminoácidos , Animais , Apoptose , Células Cultivadas , Ativação Enzimática , Fibroblastos/citologia , Fibroblastos/fisiologia , Genes ras/genética , Glutationa Transferase/metabolismo , Humanos , Isoenzimas/metabolismo , Camundongos , Camundongos Knockout , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 14 Ativada por Mitógeno/genética , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Dados de Sequência Molecular , NADPH Oxidases/metabolismo , Neoplasias/patologia , Homologia de Sequência de Aminoácidos , Transdução de Sinais , Proteínas rac1 de Ligação ao GTP/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...