The level of claudin-7 is reduced as an early event in colorectal carcinogenesis

<p>Abstract</p> <p>Background</p> <p>Compromised epithelial barriers are found in dysplastic tissue of the gastrointestinal tract. Claudins are transmembrane proteins important for tight junctions. Claudins regulate the paracellular transport and are crucial for maintaining a functional epithelial barrier. Down-regulation of the oncogenic serine protease, matriptase, induces leakiness in epithelial barriers both <it>in vivo </it>and <it>in vitro</it>. We found in an <it>in-silico </it>search tight co-regulation between <it>matriptase </it>and <it>claudin-7 </it>expression. We have previously shown that the <it>matriptase </it>expression level decreases during colorectal carcinogenesis. In the present study we investigated whether <it>claudin-7 </it>expression is likewise decreased during colorectal carcinogenesis, thereby causing or contributing to the compromised epithelial leakiness of dysplastic tissue.</p> <p>Methods</p> <p>The mRNA level of <it>claudin-7 </it>(CLDN7) was determined in samples from 18 healthy individuals, 100 individuals with dysplasia and 121 colorectal cancer patients using quantitative real time RT-PCR. In addition, immunohistochemical stainings were performed on colorectal adenomas and carcinomas, to confirm the mRNA findings.</p> <p>Results</p> <p>A 2.7-fold reduction in the <it>claudin-7 </it>mRNA level was found when comparing the biopsies from healthy individuals with the biopsies of carcinomas (p < 0.001). Reductions in the <it>claudin-7 </it>mRNA levels were also detected in mild/moderate dysplasia (p < 0.001), severe dysplasia (p < 0.01) and carcinomas (p < 0.01), compared to a control sample from the same individual. The decrease at mRNA level was confirmed at the protein level by immunohistochemical stainings.</p> <p>Conclusions</p> <p>Our results show that the <it>claudin-7 </it>mRNA level is decreased already as an early event in colorectal carcinogenesis, probably contributing to the compromised epithelial barrier in adenomas.</p

EMT and induction of miR-21 mediate metastasis development in Trp53-deficient tumours

Missense mutations in TP53 gene promote metastasis in human tumours. However, little is known about the complete loss of function of p53 in tumour metastasis. Here we show that squamous cell carcinomas generated by the specific ablation of Trp53 gene in mouse epidermis are highly metastatic. Biochemical and genome-wide mRNA and miRNA analyses demonstrated that metastases are associated with the early induction of epithelial-mesenchymal transition (EMT) and deregulated miRNA expression in primary tumours. Increased expression of miR-21 was observed in undifferentiated, prometastatic mouse tumours and in human tumours characterized by p53 mutations and distant metastasis. The augmented expression of miR-21, mediated by active mTOR and Stat3 signalling, conferred increased invasive properties to mouse keratinocytes in vitro and in vivo, whereas blockade of miR-21 in a metastatic spindle cell line inhibits metastasis development. Collectively these data identify novel molecular mechanisms leading to metastasis in vivo originated by p53 loss in epithelia

Claudin-7 Is Frequently Overexpressed in Ovarian Cancer and Promotes Invasion

Background: Claudins are tight junction proteins that are involved in tight junction formation and function. Previous studies have shown that claudin-7 is frequently upregulated in epithelial ovarian cancer (EOC) along with claudin-3 and claudin-4. Here, we investigate in detail the expression patterns of claudin-7, as well as its possible functions in EOC. Methodology/Principal Findings: A total of 95 ovarian tissue samples (7 normal ovarian tissues, 65 serous carcinomas, 11 clear cell carcinomas, 8 endometrioid carcinomas and 4 mucinous carcinomas) were studied for claudin-7 expression. In real-time RT-PCR analysis, the gene for claudin-7, CLDN7, was found to be upregulated in all the tumor tissue samples studied. Similarly, immunohistochemical analysis and western blotting showed that claudin-7 protein was significantly overexpressed in the vast majority of EOCs. Small interfering RNA-mediated knockdown of claudin-7 in ovarian cancer cells led to significant changes in gene expression as measured by microarrays and validated by RT-PCR and immunoblotting. Analyses of the genes differentially expressed revealed that the genes altered in response to claudin-7 knockdown were associated with pathways implicated in various molecular and cellular functions such as cell cycle, cellular growth and proliferation, cell death, development, and cell movement. Through functional experiments in vitro, we found that both migration and invasion were altered in cells where CLDN7 had been knocked down or overexpressed. Interestingly, claudin-7 expression was associated with a net increase in invasion, but also with a decrease in migration

BPAG1a and b Associate with EB1 and EB3 and Modulate Vesicular Transport, Golgi Apparatus Structure, and Cell Migration in C2.7 Myoblasts

BPAG1a and BPAG1b (BPAG1a/b) constitute two major isoforms encoded by the dystonin (Dst) gene and show homology with MACF1a and MACF1b. These proteins are members of the plakin family, giant multi-modular proteins able to connect the intermediate filament, microtubule and microfilament cytoskeletal networks with each other and to distinct cell membrane sites. They also serve as scaffolds for signaling proteins that modulate cytoskeletal dynamics. To gain better insights into the functions of BPAG1a/b, we further characterized their C-terminal region important for their interaction with microtubules and assessed the role of these isoforms in the cytoskeletal organization of C2.7 myoblast cells. Our results show that alternative splicing does not only occur at the 5′ end of Dst and Macf1 pre-mRNAs, as previously reported, but also at their 3′ end, resulting in expression of additional four mRNA variants of BPAG1 and MACF1. These isoform-specific C-tails were able to bundle microtubules and bound to both EB1 and EB3, two microtubule plus end proteins. In the C2.7 cell line, knockdown of BPAG1a/b had no major effect on the organization of the microtubule and microfilament networks, but negatively affected endocytosis and maintenance of the Golgi apparatus structure, which became dispersed. Finally, knockdown of BPAG1a/b caused a specific decrease in the directness of cell migration, but did not impair initial cell adhesion. These data provide novel insights into the complexity of alternative splicing of Dst pre-mRNAs and into the role of BPAG1a/b in vesicular transport, Golgi apparatus structure as well as in migration in C2.7 myoblasts

S100P enhances the motility and invasion of human trophoblast cell lines

S100P has been shown to be a marker for carcinogenesis where its expression in solid tumours correlates with metastasis and a poor patient prognosis. This protein’s role in any physiological process is, however, unknown. Here we first show that S100P is expressed both in trophoblasts in vivo as well as in some corresponding cell lines in culture. We demonstrate that S100P is predominantly expressed during the early stage of placental formation with its highest expression levels occurring during the first trimester of gestation, particularly in the invading columns and anchoring villi. Using gain or loss of function studies through overexpression or knockdown of S100P expression respectively, our work shows that S100P stimulates both cell motility and cellular invasion in different trophoblastic and first trimester EVT cell lines. Interestingly, cell invasion was seen to be more dramatically affected than cell migration. Our results suggest that S100P may be acting as an important regulator of trophoblast invasion during placentation. This finding sheds new light on a hitherto uncharacterized molecular mechanism which may, in turn, lead to the identification of novel targets that may explain why significant numbers of confirmed human pregnancies suffer complications through poor placental implantation

Educação Física Escolar: Percepções do Aluno com Deficiência1

RESUMO: a inclusão de alunos com deficiência é prevista em lei e manter boas estruturas físicas e pedagógicas na escola é um ponto fundamental para que o acesso possa acontecer. A Educação Física faz parte desta inclusão e pode proporcionar grandes melhoras na qualidade de vida de alunos com deficiência. Este estudo teve como objetivo compreender as percepções do aluno com deficiência a respeito das aulas de Educação Física. Para isso foi realizada uma pesquisa de natureza qualitativa utilizando para coleta de dados uma entrevista semiestruturada a qual foi gravada, transcrita e posteriormente analisada. A amostra foi constituída de 20 alunos com deficiência matriculados em escolas regulares da cidade de Santos Dumont - MG. A partir das entrevistas, destacou-se a percepção do aluno com deficiência a respeito da Educação Física escolar; o entendimento deles quanto ao conceito de qualidade de vida; as melhoras proporcionadas na qualidade de vida através da Educação Física; as facilidades e as dificuldades nas aulas; e as questões concernentes à relação aluno/professor e aluno/aluno. Os resultados dessa pesquisa podem auxiliar a comunidade escolar e o professor de Educação Física a melhorarem a inclusão nas escolas regulares. Além disso, as percepções dos alunos com deficiência sobre as aulas podem ajudar o professor na busca de um ambiente melhor com aulas que atendam a todos e proporcionem uma melhor qualidade de vida

Perfil dos jogadores de basquete do Novo Basquete Brasil

El objetivo del estudio es describir la trayectoria de los jugado- res de baloncesto que participan en el Nuevo Baloncesto Brasil, el princi- pal campeonato brasileño de baloncesto masculino durante la temporada 2014/2015. Para lograr el objetivo, se llevó a cabo un estudio cuantitativo en el que los datos fueron recogidos a través de cuestionarios cubiertos por 102 jugadores. Se ha tenido en cuenta el lugar de inicio de la práctica, la edad en que empezaron a jugar y cuándo comenzaron a competir, el club en el que jugaron los primeros años y si fueron convocados a la selección en categorías de base o adulta. Los resultados muestran que los jugadores de baloncesto de Brasil no se iniciaron a una edad temprana, además el inicio de la práctica y la competición se produjo alrededor de los 12 años. Cabe destacar un predominio de los clubes de Sao Paulo en el entrenamiento de los deportistas, en especial la ciudad de Franca. El 51,48% de los atletas adultos de la NBB fueron convocados a selecciones de base. Este estudio permite comprender aspectos importantes del deporte de alto nivel en Bra- sil, principalmente de baloncesto masculino.Abstract: The aim of the study was to describe the trajectory of the parti- cipating players of the New Basketball Brazil (NBB), the main Brazilian championship men’s basketball season 2014/2015. To achieve the objective of a quantitative survey was conducted in which the data collected through questionnaires given to the players. 102 athletes were investigated. We sought to map the starting location of practice, the age at which started the practice and competition in basketball, the club for which he played in the early years and whether or not summoned to the selection of adult Brazilian base and base. The results indicated that the Brazilian basketball athletes did not undergo early specialization, the age of onset of practice and com- petition are very close to the average of 12 years, there is a predominance of clubs of São Paulo in the training of athletes, especially the city of Franca, and 51.48% of adult athletes of the NBB were summoned to base selections. This study allows us to understand important aspects of top-level sport in Brazil, particularly male basketball.Resumo: O objetivo do estudo foi descrever a trajetória dos jogadores parti- cipantes do Novo Basquete Brasil (NBB), principal campeonato de basque- tebol masculino brasileiro temporada 2014/2015. Para alcançar o objetivo foi realizada uma pesquisa quantitativa em que se coletou os dados por meio de questionários entregues aos jogadores. Foram investigados 102 at- letas. Se buscou mapear o local de início da prática, idade em que iniciaram a prática e a competição no basquetebol, clube por qual jogou nos anos ini- ciais e se foi ou não convocado para a Seleção de base brasileira adulta e de base. Os resultados indicaram que, em geral, ao menos pela idade de início de prática (próxima dos 12 anos, em média), os atletas brasileiros de basque- tebol parecem não ter iniciado precocemente na modalidade, o estado de São Paulo se confirma como o centro da modalidade no país, tendo predo- minância na formação desses atletas, com destaque para a cidade de Franca; a NBB se mostra importante mercado e ambiente de desenvolvimento dos melhores atletas revelados no país, uma vez que 51,48% dos participantes foram convocados para alguma seleção de base brasileira