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In situ hybridization detection of homeobox genes reveals distinct expression patterns in oral squamous cell carcinomas

LIBORIO, Tatiana N.; ACQUAFREDA, Thais; MATIZONKAS-ANTONIO, Luciana F.; SILVA-VALENZUELA, Maria G.; FERRAZ, Alberto R.; NUNES, Fabio D.
Fonte: WILEY-BLACKWELL PUBLISHING, INC Publicador: WILEY-BLACKWELL PUBLISHING, INC
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
37.07%
Aims: To analyse the expression of three homeobox genes (HOXA7, PITX1 and PRRX1) in oral squanous cell carcinomas (OSCC) and the relationship of such expression to certain distinct histopathological features of OSCC and in comparison to adjacent non-neoplastic epithelium (NT). Methods and results: Digoxigenin-labelled riboprobes that are specific for each homeobox gene were generated and in situ hybridization was carried out on frozen sections. In NT samples, HOXA7 and PITX1 transcripts were found more frequently in all epithelial layers, while PRRX1 was expressed in the basal layer. With OSCC samples, expression of the three genes was associated with all histological features. However, the HOXA7 and PITX1 signals were more intense in sheets and nests and PRRX1 in small nests and isolated cells. Conclusion: HOXA7, PIXT1 and PRRX1 homeobox genes have different patterns of expression in OSCC depending on its histological features.; FAPESP[01/13644-6]; CAPES; CNPq

Expression of Homeobox Genes in Oral Squamous Cell Carcinoma Cell Lines Treated With All-Trans Retinoic Acid

ACQUAFREDA, Thais; NUNES, Fabio Daumas; SOPRANO, Dianne Robert; SOPRANO, Kenneth J.
Fonte: WILEY-LISS Publicador: WILEY-LISS
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
37.14%
Oral squamous cell carcinoma (OSCC) may arise from potentially malignant oral lesions. All-trans retinoic acid (atRA), which plays a role in cell growth and differentiation, has been studied as a possible chemotherapeutic agent in the prevention of this progression. While the mechanism by which atRA suppresses cell growth has not been completely elucidated, it is known that homeobox genes are atRA targets. To determine if these genes are involved in the atRA-mediated OSCC growth inhibition, PCR array was performed to evaluate the expression of 84 homeobox genes in atRA-sensitive SCC-25 cells compared to atRA-resistant SCC-9 cells following 7 days with atRA treatment. Results showed that the expression of 8 homeobox genes was downregulated and expression of 4 was upregulated in SCC-25 cells but not in SCC-9 cells. Gene expression levels were confirmed for seven of these genes by RT-qPCR. Expression of three genes that showed threefold downregulation was evaluated in SCC-25 cells treated with atRA for 3, 5, and 7 days. Three different patterns of atRA-dependent gene expression were observed. ALX1 showed downregulation only on day 7. DLX3 showed reduced expression on day 3 and further reduced on clay 7. TLX1 showed downregulation only on days 5 and 7. Clearly the expression of homeobox genes is modulated by atRA in OSCC cell lines. However...

Homeobox gene expression profile indicates HOXA5 as a candidate prognostic marker in oral squamous cell carcinoma

Rodini, Camila Oliveira; Aquino Xavier, Flavia Calo; Silva Paiva, Katiucia Batista; De Souza Setubal Destro, Maria Fernanda; Moyses, Raquel Ajub; Michaluarte, Pedro; Carvalho, Marcos Brasilino; Fukuyama, Erica Erina; Tajara, Eloiza Helena; Okamoto, Oswald
Fonte: SPANDIDOS PUBL LTD; ATHENS Publicador: SPANDIDOS PUBL LTD; ATHENS
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
37.24%
The search for molecular markers to improve diagnosis, individualize treatment and predict behavior of tumors has been the focus of several studies. This study aimed to analyze homeobox gene expression profile in oral squamous cell carcinoma (OSCC) as well as to investigate whether some of these genes are relevant molecular markers of prognosis and/or tumor aggressiveness. Homeobox gene expression levels were assessed by microarrays and qRT-PCR in OSCC tissues and adjacent non-cancerous matched tissues (margin), as well as in OSCC cell lines. Analysis of microarray data revealed the expression of 147 homeobox genes, including one set of six at least 2-fold up-regulated, and another set of 34 at least 2-fold down-regulated homeobox genes in OSCC. After qRT-PCR assays, the three most up-regulated homeobox genes (HOXA5, HOXD10 and HOXD11) revealed higher and statistically significant expression levels in OSCC samples when compared to margins. Patients presenting lower expression of HOXA5 had poorer prognosis compared to those with higher expression (P=0.03). Additionally, the status of HOXA5, HOXD10 and HOXD11 expression levels in OSCC cell lines also showed a significant up-regulation when compared to normal oral keratinocytes. Results confirm the presence of three significantly upregulated (>4-fold) homeobox genes (HOXA5...

Expressão de genes homeobox em células de carcinoma epidermóide de boca estimuladas com EGF e TGF-beta; Expression of homeobox genes in oral squamous cell carcinoma cell lines, stimulated with EGF and TGF-beta

Campos, Marcia Sampaio
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 21/01/2008 PT
Relevância na Pesquisa
37.34%
Genes homeobox, vitais para muitos aspectos relacionados com crescimento e diferenciação celular, têm sido descritos desregulados em alguns cânceres. Seu papel na carcinogênese, principalmente de carcinomas epidermóides de boca, permanence pouco claro e pobremente caracterizado. Desse modo, esse estudo objetivou avaliar, em cultura de células, o perfil de expressão de seis genes homeobox (ASH2L, HOXA7, HHEX, PKNOX1, PITX1, TGIF) selecionados dentre aqueles previamente identificados no Projeto Genoma Câncer de Cabeça e Pescoço (2001) sob estímulo de EGF e TGF-beta1. Para tal, linhagens celulares de carcinoma epidermóide de cabeça e pescoço primário (HN6) e metastático (HN31) e uma linhagem não-tumoral (HaCat) foram cultivadas sob condições-padrão. Após a confecção dos cDNAs de cada linhagem, por meio de RT-PCR, os transcritos foram amplificados e quantificados pela técnica de PCR em tempo real. Os dados foram normalizados com o gene HPRT e a quantificação relativa foi realizada seguindo o método do delta Ct. De acordo com os resultados foi possível verificar que o EGF produziu uma modulação variável da expressão dos genes avaliados em todas as linhagens celulares, enquanto que, em geral, o TGF-beta1 foi capaz de aumentar significantemente (ANOVA...

Expressão de transcritos de genes homeobox no carcinoma epidermóide de boca: análise por microarray, validação por qRT-PCR e relação com critérios clínicos de agressividade; Homeobox genes transcripts expression in oral squamous cell carcinoma: microarray analysis, qRT-PCR validation and association with clinical criteria of aggressiveness

Rodini, Camila de Oliveira
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 23/01/2009 PT
Relevância na Pesquisa
37.27%
A busca de marcadores moleculares para o refinamento diagnóstico, classificação e estabelecimento do prognóstico dos tumores, e individualização terapêutica tem sido foco de várias pesquisas. O presente estudo teve como objetivo investigar, em carcinoma epidermóide de língua e/ou assoalho bucal, a presença de transcritos dos genes homeobox que pudessem se revelar marcadores moleculares de prognóstico e/ou agressividade tumoral. Após análise por microarray utilizando-se amostras de tumores e margens classificados como mais e menos agressivos, os genes homeobox HOXC13, HOXD10, HOXD11, IRX4, PROX1 e ZHX1 foram selecionados e sua hiper-expressão foi parcialmente validada por qRT-PCR. Observou-se aumento da expressão de HOXD10, HOXD11 e IRX4 em tumores com relação às margens correspondentes, bem como nos tumores menos agressivos em relação às suas respectivas margens. Por outro lado, os genes PROX1 e ZHX1 estavam mais expressos nas margens que nos tumores correspondentes. Esses resultados sugerem que a expressão alterada de HOXD10, HOXD11 e IRX4 pode participar no desenvolvimento do carcinoma epidermóide de língua e/ou assoalho bucal, enquanto os genes PROX1 e ZHX1 provavelmente exibem perda de função ou estão silenciados na neoplasia. Houve uma tendência de associação entre a expressão elevada de HOXD11 e presença de infiltrações linfática e perineural...

Expressão de variantes transcricionais do gene Homeobox TGIF1 em carcinomas epidermóides de boca; Expression of transcript variants of the homeobox gene TGIF1 in oral squamous cell carcinoma

Santos, Tatiana Nayara Libório dos
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 15/02/2008 PT
Relevância na Pesquisa
37.24%
Genes da família homeobox têm sido alvo de intensas pesquisas científicas relacionadas ao câncer. Recentemente, mostramos que o gene homeobox TGIF1 está expresso no carcinoma epidermóide de boca na sua forma genérica. Porém, não foi feita uma discriminação entre quais variantes transcricionais, ou subtipos, do TGIF1 estariam expressas. Neste estudo, propusemo-nos a verificar diferenças na freqüência de expressão das variantes transcricionais do TGIF1 em carcinomas epidermóides de boca (CEB) em relação a tecidos morfologicamente não tumorais (TN), avaliar possíveis associações entre essas variantes nos pacientes portadores de CEB e relacionar o grau de expressão dessas variantes com aspectos clínicos, histológicos e com a sobrevida dos pacientes. Adicionalmente, procuramos analisar a expressão da proteína do TGIF1. Foram analisadas 48 amostras congeladas de CEB e 12 de TN. O RNA total de cada amostra foi extraído utilizando-se solução de TRizol®. Os transcritos do TGIF1 foram amplificados por RT-PCR para cada caso de CEB e TN utilizando-se inicialmente um par de iniciadores genéricos para todas as suas variantes. Após essa triagem, os casos positivos foram amplificados utilizando-se pares de iniciadores específicos para cada variante. Não houve diferença estatística entre a freqüência de expressão das variantes do TGIF1 nos grupos CEB e TN...

Perfil da expressão de genes homeobox em linhagens celulares de carcinoma epidermóide de boca estimuladas pelo ácido retinóico; Expression of homeobox gene in oral squamous cell carcinoma cell lines under retinoic acid stimulus

Antunes, Thaís Acquafreda
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 06/11/2009 PT
Relevância na Pesquisa
37.3%
O carcinoma epidermóide de boca, neoplasia maligna de boca mais comum, pode originar-se de lesões potencialmente malignas. O ácido retinóico, que atua no crescimento e diferenciação celular, tem sido comumente estudado como um possível quimioterápico na prevenção dessa progressão. Embora o mecanismo pelo qual o ácido retinóico previne essa progressão, e promove a parada do crescimento celular, não esteja estabelecido, sabe-se que os genes homeobox são importantes alvos do ácido retinóico durante o desenvolvimento embrionário e diferenciação tecidual. Este estudo visa determinar se a modulação da expressão desses genes está envolvida na inibição do crescimento pelo ácido retinóico em carcinoma epidermóide de boca. Para isso, foi realizado PCR array para avaliar a expressão de 84 genes homeobox na linhagem celular de carcinoma epidermóide de boca sensível ao ácido retinóico SSC-25, comparando com a linhagem resistente, SSC-9, após o tratamento com ácido retinóico por sete dias. Os resultados mostraram nove genes com perda de expressão e quatro com alta expressão. A validação por qPCR de 7 desses genes confirmou os resultados. Desses, três genes(ALX1, DLX3, TLX1) foram selecionados para terem a expressão avaliada em amostras tratadas por 3...

Análise funcional e expressão do gene homeobox HOXB7 em adenocarcinomas pancreáticos ductais; Functional analysis and expression of the homeobox gene HOXB7 in pancreatic ductal adenocarcinoma

Chile, Thais
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 12/04/2013 PT
Relevância na Pesquisa
37.24%
O adenocarcinoma pancreático ductal representa a quarta causa de morte por câncer, visto que as taxas de incidência são praticamente idênticas às taxas de mortalidade, o que justifica a natureza altamente agressiva do tumor. Em uma análise preliminar realizada por nosso grupo, avaliou-se a expressão do gene homeobox HOXB7 nas linhagens celulares MIA PaCa-2, BxPC-3 e Capan-1, bem como em tecidos pancreáticos normais, detectando-se o aumento significativo da expressão nas células derivadas de adenocarcinoma pancreático. Alterações na expressão de HOXB7 foram relatadas na formação e progressão de outros cânceres. Nessas condições, este estudo visou não somente avaliar a expressão deste gene em uma série de 29 adenocarcinomas pancreáticos ductais, 6 tecidos metastáticos e 24 tecidos peritumorais, comparando-os aos tecidos normais, mas também averiguar o efeito de sua inibição sobre o perfil de expressão das células citadas. A análise da expressão gênica demonstrou a hiperregulação do transcrito do gene HOXB7 nos tecidos tumorais, corroborando os resultados observados nas linhagens celulares MIA PaCa-2, BxPC-3 e Capan-1. A inibição realizada com RNA de interferência promoveu a modulação de diferentes processos biológicos nas três linhagens celulares pesquisadas...

Homeobox gene expression profile indicates HOXA5 as a candidate prognostic marker in oral squamous cell carcinoma

Rodini, Camila Oliveira; Xavier, Flávia Caló Aquino; Paiva, Katiúcia Batista Silva; Destro, Maria Fernanda de Souza Setúbal; Moyses, Raquel Ajub; Michaluarte, Pedro; Carvalho, Marcos Brasilino; Fukuyama, Erica Erina; Tajara, Eloiza Helena; Okamoto, Os
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 1180-1188
ENG
Relevância na Pesquisa
37.24%
The search for molecular markers to improve diagnosis, individualize treatment and predict behavior of tumors has been the focus of several studies. This study aimed to analyze homeobox gene expression profile in oral squamous cell carcinoma (OSCC) as well as to investigate whether some of these genes are relevant molecular markers of prognosis and/or tumor aggressiveness. Homeobox gene expression levels were assessed by microarrays and qRT-PCR in OSCC tissues and adjacent non-cancerous matched tissues (margin), as well as in OSCC cell lines. Analysis of microarray data revealed the expression of 147 homeobox genes, including one set of six at least 2-fold up-regulated, and another set of 34 at least 2-fold down-regulated homeobox genes in OSCC. After qRT-PCR assays, the three most up-regulated homeobox genes (HOXA5, HOXD10 and HOXD11) revealed higher and statistically significant expression levels in OSCC samples when compared to margins. Patients presenting lower expression of HOXA5 had poorer prognosis compared to those with higher expression (P=0.03). Additionally, the status of HOXA5, HOXD10 and HOXD11 expression levels in OSCC cell lines also showed a significant up-regulation when compared to normal oral keratinocytes. Results confirm the presence of three significantly upregulated (>4-fold) homeobox genes (HOXA5...

Homeobox genes: a molecular link between development and cancer

Nunes,Fabio Daumas; Almeida,Fernanda Campos Souza de; Tucci,Renata; Sousa,Suzana Cantanhede Orsini Machado de
Fonte: Sociedade Brasileira de Pesquisa Odontológica e Faculdade de Odontologia da Universidade de São Paulo Publicador: Sociedade Brasileira de Pesquisa Odontológica e Faculdade de Odontologia da Universidade de São Paulo
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2003 EN
Relevância na Pesquisa
37.3%
Homeobox genes are regulatory genes encoding nuclear proteins that act as transcription factors, regulating aspects of morphogenesis and cell differentiation during normal embryonic development of several animals. Vertebrate homeobox genes can be divided in two subfamilies: clustered, or HOX genes, and nonclustered, or divergent, homeobox genes. During the last decades, several homeobox genes, clustered and nonclustered ones, were identified in normal tissue, in malignant cells, and in different diseases and metabolic alterations. Homeobox genes are involved in the normal teeth development and in familial teeth agenesis. Normal development and cancer have a great deal in common, as both processes involve shifts between cell proliferation and differentiation. The literature is accumulating evidences that homeobox genes play an important role in oncogenesis. Many cancers exhibit expression of or alteration in homeobox genes. Those include leukemias, colon, skin, prostate, breast and ovarian cancers, among others. This review is aimed at introducing readers to some of the homeobox family functions in normal tissues and especially in cancer.

Lineage-restricted expression of homeobox-containing genes in human hematopoietic cell lines.

Shen, W F; Largman, C; Lowney, P; Corral, J C; Detmer, K; Hauser, C A; Simonitch, T A; Hack, F M; Lawrence, H J
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /11/1989 EN
Relevância na Pesquisa
27.35%
We investigated the role of homeobox-containing genes in human hematopoiesis because homeobox genes (i) control cell fate in the Drosophila embryo, (ii) are expressed in specific patterns in human embryos, and (iii) appear to function as transcription factors that control cell phenotype in other mammalian organs. Using four homeobox probes from the HOX2 locus and a previously undescribed homeobox cDNA (PL1), we screened mRNAs from 18 human leukemic cell lines representing erythroid, myeloid, and T- and B-cell lineages. Complex patterns of lineage-restricted expression are observed: some are restricted to a single lineage, while others are expressed in multiple lineages. No single homeobox gene is expressed in all types of hematopoietic cells, but each cell type exhibits homeobox gene expression. HOX2.2 and -2.3 homeobox-containing cDNAs were cloned from an erythroleukemia cell (HEL) cDNA library, while the homeobox cDNA PL1 was isolated from a monocytic cell (U-937) library. Differentiation of HEL and K-562 cells with various inducers results in modulation of specific homeobox transcripts. In addition, HOX2.2 is expressed in normal bone marrow cells. We have demonstrated (i) lineage-restricted expression of five homeobox genes in erythroid and monocytic cell lines; (ii) expression of additional homeobox genes in other cell lineages (HL-60 and lymphoid cells); (iii) expression of one homeobox gene in normal marrow cells; and (iv) modulation of expression during differentiation. These data suggest that these genes play a role in human hematopoietic development and lineage commitment.

Infantile spasms, dystonia, and other X-linked phenotypes caused by mutations in Aristaless related homeobox gene, ARX

Stromme, P.; Mangelsdorf, M.; Scheffer, I.; Gecz, J.
Fonte: Elsevier Science BV Publicador: Elsevier Science BV
Tipo: Artigo de Revista Científica
Publicado em //2002 EN
Relevância na Pesquisa
36.84%
Clinical data from 50 mentally retarded (MR) males in nine X-linked MR families, syndromic and non-specific, with mutations (duplication, expansion, missense, and deletion mutations) in the Aristaless related homeobox gene, ARX, were analysed. Seizures were observed with all mutations and occurred in 29 patients, including one family with a novel myoclonic epilepsy syndrome associated with the missense mutation. Seventeen patients had infantile spasms. Other phenotypes included mild to moderate MR alone, or with combinations of dystonia, ataxia or autism. These data suggest that mutations in the ARX gene are important causes of MR, often associated with diverse neurological manifestations.; Strømme, Petter ; Mangelsdorf, Marie E ; Scheffer, Ingrid E ; Gécz, Jozef

ARX, a novel Prd-class-homeobox gene highly expressed in the telencephalon, is mutated in X-linked mental retardation

Bienvenu, T.; Poirier, K.; Friocourt, G.; Bahi, N.; Beaumont, D.; Fauchereau, F.; Jeema, L.; Zemni, R.; Vinet, M.C.; Francis, F.; Couvert, P.; Gomot, M.; Moraine, C.; van Bokhoven, H.; Kalscheuer, V.; Frints, S.; Gecz, J.; Ohzaki, K.; Chaabouni, H.; Fryns
Fonte: Oxford Univ Press Publicador: Oxford Univ Press
Tipo: Artigo de Revista Científica
Publicado em //2002 EN
Relevância na Pesquisa
36.84%
Investigation of a critical region for an X-linked mental retardation (XLMR) locus led us to identify a novel Aristaless related homeobox gene (ARX ). Inherited and de novo ARX mutations, including missense mutations and in frame duplications/insertions leading to expansions of polyalanine tracts in ARX, were found in nine familial and one sporadic case of MR. In contrast to other genes involved in XLMR, ARX expression is specific to the telencephalon and ventral thalamus. Notably there is an absence of expression in the cerebellum throughout development and also in adult. The absence of detectable brain malformations in patients suggests that ARX may have an essential role, in mature neurons, required for the development of cognitive abilities.; Thierry Bienvenu, Karine Poirier, Gaelle Friocourt, Nadia Bahi, Delphine Beaumont, Fabien Fauchereau, Lamia Ben Jeema, Ramzi Zemni, Marie-Claude Vinet, Fiona Francis, Philippe Couvert, Marie Gomot, Claude Moraine, Hans van Bokhoven, Vera Kalscheuer, Suzanne Frints, Josef Gecz, Kanae Ohzaki, Habiba Chaabouni, Jean-Pierre Fryns, Vincent Desportes, Cherif Beldjord and Jamel Chelly

Expression of the homeobox gene Barx2 in the gut

Sander, G.; Powell, B.
Fonte: Histochemical Soc Inc Publicador: Histochemical Soc Inc
Tipo: Artigo de Revista Científica
Publicado em //2004 EN
Relevância na Pesquisa
36.84%
Barx2 is a member of the Bar class of homeobox genes and has been shown to regulate specific cell adhesion molecules, L1, Ng-CAM, N-CAM, and cadherin 6. By Northern blotting and in situ hybridization, we show that Barx2 is expressed throughout the gut and is located in epithelial cells of the proliferative and differentiative regions of the stomach, esophagus, and intestine. Barx2 was expressed in muscle cells of the muscularis externa and also showed a graded pattern of expression in intestinal enterocytes, decreasing in a crypt-to-villous direction. We speculate that Barx2 may regulate cell adhesion molecules in epithelial cells of the gut.; Guy R. Sander and Barry C. Powell; © The Histochemical Society

X-linked myoclonic epilepsy with spasticity and intellectual disability - Mutation in the homeobox gene ARX

Scheffer, I.; Wallace, R.; Phillips, F.; Hewson, P.; Reardon, K.; Parasivam, G.; Stromme, P.; Berkovic, S.; Gecz, J.; Mulley, J.
Fonte: Lippincott Williams & Wilkins Publicador: Lippincott Williams & Wilkins
Tipo: Artigo de Revista Científica
Publicado em //2002 EN
Relevância na Pesquisa
36.84%
OBJECTIVE: To describe a new syndrome of X-linked myoclonic epilepsy with generalized spasticity and intellectual disability (XMESID) and identify the gene defect underlying this disorder. METHODS: The authors studied a family in which six boys over two generations had intractable seizures using a validated seizure questionnaire, clinical examination, and EEG studies. Previous records and investigations were obtained. Information on seizure disorders was obtained on 271 members of the extended family. Molecular genetic analysis included linkage studies and mutational analysis using a positional candidate gene approach. RESULTS: All six affected boys had myoclonic seizures and TCS; two had infantile spasms, but only one had hypsarrhythmia. EEG studies show diffuse background slowing with slow generalized spike wave activity. All affected boys had moderate to profound intellectual disability. Hyperreflexia was observed in obligate carrier women. A late-onset progressive spastic ataxia in the matriarch raises the possibility of late clinical manifestations in obligate carriers. The disorder was mapped to Xp11.2-22.2 with a maximum lod score of 1.8. As recently reported, a missense mutation (1058C>T/P353L) was identified within the homeodomain of the novel human Aristaless related homeobox gene (ARX). CONCLUSIONS: XMESID is a rare X-linked recessive myoclonic epilepsy with spasticity and intellectual disability in boys. Hyperreflexia is found in carrier women. XMESID is associated with a missense mutation in ARX. This disorder is allelic with X-linked infantile spasms (ISSX; MIM 308350) where polyalanine tract expansions are the commonly observed molecular defect. Mutations of ARX are associated with a wide range of phenotypes; functional studies in the future may lend insights to the neurobiology of myoclonic seizures and infantile spasms.; http://www.neurology.org/cgi/content/abstract/59/3/348

Sequence, genomic organization and expression of the novel homeobox gene Hesx1

Thomas, P.; Johnson, B.; Rathjen, J.; Rathjen, P.
Fonte: The American Society for Biochemistry and Molecular Biology Inc Publicador: The American Society for Biochemistry and Molecular Biology Inc
Tipo: Artigo de Revista Científica
Publicado em //1995 EN
Relevância na Pesquisa
37.07%
Extensive analyses of homeobox gene expression and function during murine embryogenesis have demonstrated that homeobox gene products are key components in the establishment of pattern formation and regional identity during development. In this paper we report the molecular characterization and expression of a novel murine homeobox sequence, Hesx1, isolated from pluripotent embryonic stem cells. Hesx1 is expressed as two transcripts of 1.0 and 1.2 kilobases which encode an identical 185 amino acid open reading frame. The transcripts differ in the 3'-untranslated region due to the differential utilization of a weak splice donor site located immediately downstream of the translation termination codon. The Hesx1 homeodomain shared 80% identity with the Xenopus homeoprotein XANF-1 and was less than 50% related to other homeodomain sequences. Hesx1 and XANF-1 therefore constitute the founder members of a new homeodomain class. Hesx1 expression was down-regulated during embryonic stem cell differentiation and was detected in tissue-specific RNA samples derived from the embryonic liver, and at lower levels in viscera, amnion, and yolk sac. Expression in adult mice was not detected. These sites of expression are consistent with a role for Hesx1 in the regulation of developmental decisions in the early mouse embryo and during fetal hematopoiesis.; Paul Q. Thomas...

Molecular cloning of a human Vent-like homeobox gene

Moretti, P.; Davidson, A.; Baker, E.; Lilley, B.; Zon, L.; D'Andrea, R.
Fonte: Academic Press Inc Publicador: Academic Press Inc
Tipo: Artigo de Revista Científica
Publicado em //2001 EN
Relevância na Pesquisa
37.07%
We have isolated a previously unknown human homeobox-containing cDNA, VENT-like homeobox-2 (VENTX2), using PCR with a bone marrow cDNA library and primers designed from the VENTX1 (alias HPX42) homeobox sequence. Here we describe the molecular cloning, chromosomal localization to 10q26.3, and functional analysis of this gene. The 2.4-kb human VENTX2 cDNA encoded a protein with a predicted molecular weight of 28 kDa containing a homeodomain with 65% identity to the Xenopus laevis ventralizing gene Xvent2B. VENTX2 antisera detected a 28-kDa protein in cells transfected with a VENTX2 expression construct, in a human erythroleukemic cell line and in bone marrow samples obtained from patients in recovery phase after chemotherapy. The similarity of the homeodomains from VENTX2 and the X. laevis Vent gene family places them in the same homeodomain class. Consistent with this structural classification, overexpression of VENTX2 in zebrafish embryos led to anterior truncations and failure to form a notochord, which are characteristics of ventralization.

Modulación de la expresión de genes homeóticos en el desarrollo de la glándula mamaria murina; Modulation of homeobox gene expression during mouse mammary gland development

Srebrow, Anabella
Fonte: Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires Publicador: Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires
Tipo: info:eu-repo/semantics/doctoralThesis; tesis doctoral; info:eu-repo/semantics/publishedVersion Formato: application/pdf
Publicado em //1997 SPA
Relevância na Pesquisa
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Los genes homeóticos codifican para reguladores transcripcionales involucrados en la formación de patrones y las decisiones de destino celular durante la embriogénesis. Recientemente, ha despertado gran interés la función de dichos genes en tejidos adultos en continuo desarrollo así como también en procesos tumorigénicos. La mayor parte del crecimiento y morfogénesis de la glándula mamaria ocurre durante la vida subadulta y adulta del animal y ciertos estadios de la glándula postnatal presentan características de tipo embrionarias. Regulación de fomación de patrones, diferenciación celular e interacciones epitelio-estroma tienen lugar una vez finalizada la embriogénesis y reocurren durante cada ciclo de preñez, lactancia e involución. Debido a que la matriz extracelular influencia el desarrollo funcional y morfogenético de la glándula mamaria, investigamos si las señales provenientes de dicha matriz podrían estar involucradas en la expresión y regulación de genes homeóticos. Mediante una estrategia basada en reacciones en cadena de polimerasa, identificamos la expresión de 5 genes homeóticos pertenecientes a dos "clusters" del complejo Hox, en células mamarias murinas en cultivo. Un gen de cada uno de estos "clusters"...

The Pem homeobox gene: rapid evolution of the homeodomain, X chromosomal localization, and expression in reproductive tissue

Maiti, Sourindra; Doskow, Jessica; Sutton, Keith; Nhim, Ronald; Lawlor, David; Leyan, Karin; Lindsey, J.; Wilkinson, Miles
Fonte: Elsevier: Genomics Publicador: Elsevier: Genomics
Tipo: Artigo de Revista Científica Formato: 37365 bytes; application/pdf
EN_US
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A hallmark of homeobox genes is their high degree of sequence conservation in distantly related species. Here, we report the chromosomal localization, sequence, and expression pattern of an orphan homeobox gene,Pem,that encodes a homeodomain (HD) that has undergone a surprisingly high rate of evolutionary change. The N-terminal portion of thePemHD, which includes the first two α-helices, exhibits only 44% sequence identity between ratPem(r.Pem) and mousePem(m.Pem). This N-terminal subdomain exhibited an extremely high frequency of nonsynonymous substitutions, severalfold higher than other regions of thePemprotein. In contrast, the third helix, which is known to confer most of the base-specific contacts of HDs with DNA, was almost identical inr.Pemandm.Pem.Several lines of evidence suggested that the rat and mouse genes that we identified asPemgenes are true homologues: (1) ther.Pemandm.Pemgenes both reside on the X chromosome; (2) they possess identical exon/intron splice junctions; (3) they both encode a distinctive motif upstream of the HD that is unique toPem;and (4) the onlym.Pem-like gene we were able to identify in the rat genome other thanr.Pemwas a pseudogene,r.Pem-ps,whose sequence and chromosomal localization indicated that it was derived by reverse transcription and reinsertion into the genome. The functionalr.Pemgene is selectively expressed in placenta...

Genes homeobox: uma relação molecular entre o desenvolvimento e o câncer; Homeobox genes: a molecular link between development and cancer

Nunes, Fabio Daumas; Almeida, Fernanda Campos Souza de; Tucci, Renata; Sousa, Suzana Cantanhede Orsini Machado de
Fonte: Universidade de São Paulo. Faculdade de Odontologia Publicador: Universidade de São Paulo. Faculdade de Odontologia
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; Artigo Avaliado pelos Pares Formato: application/pdf
Publicado em 01/03/2003 ENG
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Os genes homeobox são genes reguladores que codificam proteínas nucleares as quais atuam como fatores de transcrição, regulando vários aspectos da morfogênese e da diferenciação celular durante o desenvolvimento embrionário normal de diversos animais. Os genes homeobox de vertebrados podem ser subdivididos em duas famílias: os agrupados, ou HOX, e os não agrupados, ou divergentes. Durante as últimas décadas, vários genes homeobox, agrupados e não agrupados, foram identificados em tecidos normais, em células malignas e em diferentes doenças e condições metabólicas. Os genes homeobox estão envolvidos, por exemplo, no desenvolvimento normal do dente e em agenesias dentárias de ocorrência familiar. O desenvolvimento normal e o câncer têm muito em comum, já que ambos envolvem proliferação celular e diferenciação. A literatura tem mostrado um número cada vez maior de trabalhos relacionando os genes homeobox à oncogênese. Muitos tipos de câncer exibem expressão ou alteração nos genes homeobox. Eles incluem leucemias, câncer de cólon, pele, próstata, mama e ovário, entre outros. Esta revisão objetiva levar os leitores a conhecer algumas das funções da família homeobox nos tecidos normais e especialmente no câncer.; Homeobox genes are regulatory genes encoding nuclear proteins that act as transcription factors...