The number of new cancer cases is projected to rise to 23.6 million by 2030 according to the National Cancer Institute. Obesity & cardiovascular diseases are among the leading causes of death worldwide according to recent reports. Biomarkers— any molecules found within a human body that can be used to monitor an individual's health — have been shown to play a significant role in the detection of cancer, obesity, and cardiovascular diseases. Recent studies have shown that in the diagnosis and screening of various human diseases, including cancer, obesity and cardiovascular diseases, circulating microRNAs (miRNAs) are important biomarkers. A crucial roadblock to using microRNA in screening applications is the lack of effective and low-cost microRNA detection. To address this issue, in this study, we have developed a viable method that combines the dielectrophoresis and electrical impedance. Results show this approach can measure very small concentrations of label-free microRNAs (1pM).

O meduloblastoma é o tumor cerebral maligno mais comum em crianças de zero a quatro anos e uma das principais causas de morbidade e mortalidade infantil. Diversos estudos têm suportado a hipótese de que a ativação de genes tipicamente expressos em células-tronco confere características mais primitivas e agressivas a células tumorais, frequentemente associadas a prognóstico clínico desfavorável. Nesse contexto, tanto fatores proteicos quanto miRNAs poderiam estimular uma reprogramação em células cancerosas, induzindo um fenótipo semelhantes ao de células-tronco. Estudos recentes apontam o envolvimento do miR-367 na reprogramação de fibroblastos ao estado pluripotente e sua expressão aberrante foi correlacionada com prognóstico desfavorável em alguns tipos de câncer. Neste trabalho, verificou-se um possível papel funcional do miR-367 na agressividade de meduloblastoma. Células de meduloblastoma de quatro diferentes linhagens, Daoy, D283-Med, CHLA-01-Med e USP-13-Med apresentaram níveis baixos de expressão de pri-miR-367 e miR-367 maduro, em relação aos níveis encontrados em células-tronco embrionárias humanas. Uma superexpressão transiente do miR-367 em células das linhagens CHLA-01-Med e USP-13-Med resultaram em uma redução significativa dos níveis proteicos de RYR3, bem como dos transcritos preditos de ITGAV e RAB23, respectivos alvos do miR-367, envolvidos em câncer. Além disso, a superexpressão de miR-367 aumentou significativamente a proliferação celular, indicada pela cinética de crescimento in vitro e pela maior porcentagem de células presentes nas fases S+G2/M do ciclo celular. Embora a sensibilidade ao tratamento com cisplatina não tenha sido alterada após superexpressão de miR-367, a capacidade de geração de neuroesferas in vitro foi significativamente aumentada. Este último resultado é interessante do ponto de vista clínico, uma vez que a capacidade de geração de neuroesferas está significativamente correlacionada com menor sobrevida de pacientes com meduloblastoma. Portanto, esses achados sugerem uma função pró-oncogênica ao miR-367, a qual pode afetar a agressividade de meduloblastoma por meio de efeitos positivos sobre a proliferação celular e propriedades de células-tronco neurais / Medulloblastoma is the most common malignant brain tumor in children aged four and younger, and is the leading cause of infant morbidity and mortality. Several studies have reported the activation of stem cell genes leading to more primitive and aggressive characteristics in tumor cell often associated with unfavorable clinical prognosis. Cell reprogramming, stimulated by tumor microenvironment factors, might induce tumor stem cells phenotype. Recent researches suggest an involvement of miR-367 in fibroblasts reprogramming into pluripotent state, as well as a correlation with poor prognosis in some cancers. In this study, we observed a possible functional role of miR-367 in medulloblastoma aggressiveness. Four different medulloblastoma cell lines, Daoy, D283-Med, CHLA-01-Med and USP-13-Med showed low rates of pri-miR-367 and mature miR-367 expression. Overexpression of miR-367 down-regulated the protein levels of its target RYR3 and of two bioinformatically predicted transcript targets encoding ITGAV and RAB23, which are involved in cancer in CHLA-01-Med and USP-13 Med cell lines. Furthermore, transfection with the miRNA mimic significantly increased cell proliferation and the percentage of cells observed in S + G2 / M phase of the cell cycle. Although the sensitivity to cisplatin treatment was not changed after overexpression of miR-367, the ability to generate neurospheres in vitro was significantly increased. This last result can be related to clinical ones because cells from medulloblastoma patients with low survival show great ability to generate neurospheres. In sum, these findings suggest a pro-oncogenic role to miR-367, which can affect medulloblastoma aggressiveness by cell proliferation and neural stem cells positive modifications

O meduloblastoma é o tumor cerebral maligno mais comum em crianças de zero a quatro anos e uma das principais causas de morbidade e mortalidade infantil. Diversos estudos têm suportado a hipótese de que a ativação de genes tipicamente expressos em células-tronco confere características mais primitivas e agressivas a células tumorais, frequentemente associadas a prognóstico clínico desfavorável. Nesse contexto, tanto fatores proteicos quanto miRNAs poderiam estimular uma reprogramação em células cancerosas, induzindo um fenótipo semelhantes ao de células-tronco. Estudos recentes apontam o envolvimento do miR-367 na reprogramação de fibroblastos ao estado pluripotente e sua expressão aberrante foi correlacionada com prognóstico desfavorável em alguns tipos de câncer. Neste trabalho, verificou-se um possível papel funcional do miR-367 na agressividade de meduloblastoma. Células de meduloblastoma de quatro diferentes linhagens, Daoy, D283-Med, CHLA-01-Med e USP-13-Med apresentaram níveis baixos de expressão de pri-miR-367 e miR-367 maduro, em relação aos níveis encontrados em células-tronco embrionárias humanas. Uma superexpressão transiente do miR-367 em células das linhagens CHLA-01-Med e USP-13-Med resultaram em uma redução significativa dos níveis proteicos de RYR3, bem como dos transcritos preditos de ITGAV e RAB23, respectivos alvos do miR-367, envolvidos em câncer. Além disso, a superexpressão de miR-367 aumentou significativamente a proliferação celular, indicada pela cinética de crescimento in vitro e pela maior porcentagem de células presentes nas fases S+G2/M do ciclo celular. Embora a sensibilidade ao tratamento com cisplatina não tenha sido alterada após superexpressão de miR-367, a capacidade de geração de neuroesferas in vitro foi significativamente aumentada. Este último resultado é interessante do ponto de vista clínico, uma vez que a capacidade de geração de neuroesferas está significativamente correlacionada com menor sobrevida de pacientes com meduloblastoma. Portanto, esses achados sugerem uma função pró-oncogênica ao miR-367, a qual pode afetar a agressividade de meduloblastoma por meio de efeitos positivos sobre a proliferação celular e propriedades de células-tronco neurais / Medulloblastoma is the most common malignant brain tumor in children aged four and younger, and is the leading cause of infant morbidity and mortality. Several studies have reported the activation of stem cell genes leading to more primitive and aggressive characteristics in tumor cell often associated with unfavorable clinical prognosis. Cell reprogramming, stimulated by tumor microenvironment factors, might induce tumor stem cells phenotype. Recent researches suggest an involvement of miR-367 in fibroblasts reprogramming into pluripotent state, as well as a correlation with poor prognosis in some cancers. In this study, we observed a possible functional role of miR-367 in medulloblastoma aggressiveness. Four different medulloblastoma cell lines, Daoy, D283-Med, CHLA-01-Med and USP-13-Med showed low rates of pri-miR-367 and mature miR-367 expression. Overexpression of miR-367 down-regulated the protein levels of its target RYR3 and of two bioinformatically predicted transcript targets encoding ITGAV and RAB23, which are involved in cancer in CHLA-01-Med and USP-13 Med cell lines. Furthermore, transfection with the miRNA mimic significantly increased cell proliferation and the percentage of cells observed in S + G2 / M phase of the cell cycle. Although the sensitivity to cisplatin treatment was not changed after overexpression of miR-367, the ability to generate neurospheres in vitro was significantly increased. This last result can be related to clinical ones because cells from medulloblastoma patients with low survival show great ability to generate neurospheres. In sum, these findings suggest a pro-oncogenic role to miR-367, which can affect medulloblastoma aggressiveness by cell proliferation and neural stem cells positive modifications

No description available.

A infertilidade afeta aproximadamente 15% dos casais, sendo atualmente reconhecido o envolvimento de fatores masculinos em metade dos casos. Alterações nas análises seminais são detectadas na maioria dos homens inférteis e a mais frequente é a baixa concentração de espermatozoides no ejaculado, conhecida como oligozoospermia. Vários estudos mostram uma forte relação entre fatores genéticos e a infertilidade, incluindo alterações cromossômicas e microdeleções do cromossomo Y, porém as causas da oligozoospermia ainda permanecem obscuras. O desenvolvimento de novas tecnologias de investigação vem possibilitando a detecção de alterações a nível genômico, como mutações e variações no número de cópias (CNVs). O presente trabalho teve por objetivo a caracterização genômica de homens com oligozoospermia sem causa definida, visando estabelecer correlação entre alterações no número de cópias e perdas de heterozigosidade (LOHs) e o fenótipo de infertilidade. Foram selecionados 18 pacientes após rigorosa avaliação clínica e investigação do histórico reprodutivo, sendo excluídos pacientes portadores de alterações cromossômicas e portadores de microdeleções do cromossomo Y. Seis homens comprovadamente férteis foram selecionados para o grupo controle. A investigação genômica de ambos os grupos, amostral e controle, foi realizada pela técnica de hibridação genômica comparativa em microarranjos (aCGH) utilizando a plataforma de resolução 180K (Agilent®,US), analisada pelo software Nexus 8.0. Foram detectadas alterações possivelmente patogênicas no cromossomo Y, no cromossomo X e em autossomos. Um ganho na região de AZFc envolvendo apenas os genes DAZ1 e DAZ4 foi detectado em nove pacientes e em quatro controles, sendo classificado como alteração benigna. Porém, alterações na região de AZFc possivelmente relacionadas ao fenótipo de oligozoospermia foram detectadas em três pacientes e incluíram extensas duplicações e deleções envolvendo, entre outros genes, as quatro cópias do gene DAZ. Após comparação de regiões selecionadas com a literatura e com diferentes bancos de dados genéticos, sugerimos que os genes PLEC, SPATC1, COL1A1, MOV10L1, SYCE3 e ODF3B possam estar associados a alterações na produção espermática. Adicionalmente, entre os doze miRNAs presentes em regiões de LOH possivelmente relacionadas ao fenótipo de infertilidade, dez têm como alvo genes com funções relacionadas à espermatogênese e reprodução humana. Estudos adicionais a nível de expressão e sequenciamento gênico são necessários para confirmar a correlação entre o genótipo e o fenótipo de oligozoospermia. / Infertility affects about 15% of the couples, and it is currently recognized, that male factors are involved in about 50% of cases. Changes in seminal parameters are detected in most infertile men and the most common alteration, known as oligozoospermia, is a low concentration of sperm in the ejaculate. Several studies show a strong relationship between genetic factors and infertility, including chromosomal abnormalities and microdeletions of Y chromosome, however, the causes of oligozoospermia remain unclear. The development of new research technologies has allowed the detection of changes at genomic levels, such as mutations and copy number variations (CNVs). This study aimed to perform a genomic characterization of patients with idiopathic oligozoospermia to determine whether there is a correlation between changes of copy number and losses of heterozygosity (LOHs) in relation to the phenotype of infertility. Eighteen patients were selected for the cases after rigorous clinical examination and investigation of their reproductive history. Patients with chromosomal abnormalities or microdeletions of the Y chromosome were excluded. Six proven fertile men comprised the control group. Genomic investigation of both groups was performed by microarray comparative genomic hybridization (aCGH) using 4X180K platform (Agilent, US) analysed by Nexus 8.0 software. Potential pathogenic changes were detected on Y chromosome, as well as on the X and autosome chromosomes. A gain in AZFc region involving only DAZ1 and DAZ4 genes was detected in nine patients and four controls, and was considered as benign. However, changes in AZFc region, that could be related to the oligozoospermia phenotype were detected in three patients. These changes included extensive duplications and deletions involving the four copies of the DAZ gene together with copy number changes affecting other genes. After comparing the selected regions with the literature and with different databases, we suggest that changes such as LOH affecting PLEC, SPATC1, COL1A1, MOV10L1, SYCE3 and ODF3B genes may influence sperm production. Our analysis indicates that, ten out of the twelve miRNAs present in LOH regions could be involved in the infertility phenotype and could have target genes with functions related to spermatogenesis and human reproduction. Additional studies involving gene sequencing and expression analysis are needed to confirm the the correlation between the genotype and oligozoospermia phenotype.

A infertilidade afeta aproximadamente 15% dos casais, sendo atualmente reconhecido o envolvimento de fatores masculinos em metade dos casos. Alterações nas análises seminais são detectadas na maioria dos homens inférteis e a mais frequente é a baixa concentração de espermatozoides no ejaculado, conhecida como oligozoospermia. Vários estudos mostram uma forte relação entre fatores genéticos e a infertilidade, incluindo alterações cromossômicas e microdeleções do cromossomo Y, porém as causas da oligozoospermia ainda permanecem obscuras. O desenvolvimento de novas tecnologias de investigação vem possibilitando a detecção de alterações a nível genômico, como mutações e variações no número de cópias (CNVs). O presente trabalho teve por objetivo a caracterização genômica de homens com oligozoospermia sem causa definida, visando estabelecer correlação entre alterações no número de cópias e perdas de heterozigosidade (LOHs) e o fenótipo de infertilidade. Foram selecionados 18 pacientes após rigorosa avaliação clínica e investigação do histórico reprodutivo, sendo excluídos pacientes portadores de alterações cromossômicas e portadores de microdeleções do cromossomo Y. Seis homens comprovadamente férteis foram selecionados para o grupo controle. A investigação genômica de ambos os grupos, amostral e controle, foi realizada pela técnica de hibridação genômica comparativa em microarranjos (aCGH) utilizando a plataforma de resolução 180K (Agilent®,US), analisada pelo software Nexus 8.0. Foram detectadas alterações possivelmente patogênicas no cromossomo Y, no cromossomo X e em autossomos. Um ganho na região de AZFc envolvendo apenas os genes DAZ1 e DAZ4 foi detectado em nove pacientes e em quatro controles, sendo classificado como alteração benigna. Porém, alterações na região de AZFc possivelmente relacionadas ao fenótipo de oligozoospermia foram detectadas em três pacientes e incluíram extensas duplicações e deleções envolvendo, entre outros genes, as quatro cópias do gene DAZ. Após comparação de regiões selecionadas com a literatura e com diferentes bancos de dados genéticos, sugerimos que os genes PLEC, SPATC1, COL1A1, MOV10L1, SYCE3 e ODF3B possam estar associados a alterações na produção espermática. Adicionalmente, entre os doze miRNAs presentes em regiões de LOH possivelmente relacionadas ao fenótipo de infertilidade, dez têm como alvo genes com funções relacionadas à espermatogênese e reprodução humana. Estudos adicionais a nível de expressão e sequenciamento gênico são necessários para confirmar a correlação entre o genótipo e o fenótipo de oligozoospermia. / Infertility affects about 15% of the couples, and it is currently recognized, that male factors are involved in about 50% of cases. Changes in seminal parameters are detected in most infertile men and the most common alteration, known as oligozoospermia, is a low concentration of sperm in the ejaculate. Several studies show a strong relationship between genetic factors and infertility, including chromosomal abnormalities and microdeletions of Y chromosome, however, the causes of oligozoospermia remain unclear. The development of new research technologies has allowed the detection of changes at genomic levels, such as mutations and copy number variations (CNVs). This study aimed to perform a genomic characterization of patients with idiopathic oligozoospermia to determine whether there is a correlation between changes of copy number and losses of heterozygosity (LOHs) in relation to the phenotype of infertility. Eighteen patients were selected for the cases after rigorous clinical examination and investigation of their reproductive history. Patients with chromosomal abnormalities or microdeletions of the Y chromosome were excluded. Six proven fertile men comprised the control group. Genomic investigation of both groups was performed by microarray comparative genomic hybridization (aCGH) using 4X180K platform (Agilent, US) analysed by Nexus 8.0 software. Potential pathogenic changes were detected on Y chromosome, as well as on the X and autosome chromosomes. A gain in AZFc region involving only DAZ1 and DAZ4 genes was detected in nine patients and four controls, and was considered as benign. However, changes in AZFc region, that could be related to the oligozoospermia phenotype were detected in three patients. These changes included extensive duplications and deletions involving the four copies of the DAZ gene together with copy number changes affecting other genes. After comparing the selected regions with the literature and with different databases, we suggest that changes such as LOH affecting PLEC, SPATC1, COL1A1, MOV10L1, SYCE3 and ODF3B genes may influence sperm production. Our analysis indicates that, ten out of the twelve miRNAs present in LOH regions could be involved in the infertility phenotype and could have target genes with functions related to spermatogenesis and human reproduction. Additional studies involving gene sequencing and expression analysis are needed to confirm the the correlation between the genotype and oligozoospermia phenotype.

Ribosomes, large enzymatic complexes containing an RNA catalytic core, drive protein synthesis in all living organisms. 80S cytoplasmic eukaryotic ribosomes are comprised of four rRNAs and approximately 80 ribosomal proteins (r-proteins). R-proteins are encoded by gene families with large families (average of twelve members) predominating in mammals and smaller families (two to seven members) in plants. Increased ribosome heterogeneity is possible in plant ribosomes due to multiple transcriptionally active members in each family, whereas, in mammalian r-protein gene families, only one member is typically active. Multiple functional paralogs provide for greater plasticity in response to environmental/developmental cues, as well as, increasing the possibility of individual paralogs procuring or retaining extraribosomal functions. This research investigated the effects of r-protein mutations on plant growth and development. Through RNA interference (RNAi) mediated knockdown (KD) of type I (cytoplasmic: RPS15aA/D and F) and type II (non-cytosolic: RPS15aB and E) RPS15a family members I was able to confirm the delineation between the two types. Subcellular localization of the type I isoforms was nuclear/nucleolar while localization of type II isoforms was non-mitochondrial and probably cytosolic. Illumina sequencing of two r-protein mutant transcriptomes, pfl1 (rps18a) and pfl2 (rps13a), identified a novel set of up and down regulated genes, previously unknown or linked to r-protein mutants. The 20 genes identified were classified into four groups (1) plant defense, (2) transposable elements, (3) nitrogen metabolism and (4) genes with unknown function. Illumina miRNOME analysis revealed no changes in the miRNA profile of pfl1 and pfl2 plants. These data do not support the previously proposed theory that a disruption in ribosome biogenesis (by decreased r-protein synthesis) disrupts miRNA-mediated degradation of a range of auxin response genes. Finally, a novel double r-protein mutant, rps18a:HF/RPL18B, presented a late flowering/thickened bolt phenotype not seen in a rps13a:HF/RPL18B mutant, suggesting that RPS18A has an extraribosomal role in plant growth and development in Arabidopsis.

Les miARN sont de petits ARN non codant dont la taille varie entre 21-24 nucléotides. Ils jouent un rôle de régulateurs post-transcriptionnels en utilisant leur complémentarité de séquence avec l’ARN messager (ARNm) cible afin d’induire sa répression. Grâce à la protéine Argonaute 2 (Ago2) dans laquelle les miARN sont incorporés formant ainsi le complexe miRISC, des cofacteurs sont recrutés afin d’induire la dégradation ou le blocage de la traduction de l’ARNm cible. Initialement connus pour réguler leurs cibles dans le cytoplasme, les miARN sont de plus en plus décrits comme étant des régulateurs de l’expression génique au niveau nucléaire. Dans ce travail, nous avons démontré la présence, au sein du noyau, d’un nouveau mécanisme de régulation post-transcriptionel par les miARN dont les facteurs majeurs sont Sfpq et Pspc1 / Micro-RNA, nuclear regulation, gene silencing, SfpqThere is a growing body of evidence about the presence and the activity of the miRISC in the nucleus of mammalian cells. Here we show by quantitative proteomic analysis that Ago2 interacts with the complex formed by Sfpq, Pspc1 and NonO in a RNA-dependent fashion. Sfpq mediates the interaction between miRISC with Pspc1 and NonO in the nucleoplasm. By HITS-CLIP coupled with transcriptomic analysis, we demonstrated that Sfpq specifically controls the downregulation of a subset of crucial let-7a-target mRNAs in stem cells, including Lin28a, Prtg, and Igf2bp1. Sfpq directly binds to specific sequence in the 3'UTR to promote the recruitment of selected nucleoplasmic miRNAs and triggers the decay, as we show for Lin28a mRNA. These results extend the miRNA-mediated post-transcriptional gene silencing into the nucleus and indicate that a dual strategy

Arabidopsis thaliana HYL1 is a nuclear doublestranded RNA-binding protein involved in the maturation of pri-miRNAs. A quantitative real-time PCR platform for parallel quantification of 176 primiRNAs was used to reveal strong accumulation of 57 miRNA precursors in the hyl1 mutant that completely lacks HYL1 protein. This approach enabled us for the first time to pinpoint particular members of MIRNA family genes that require HYL1 activity for efficient maturation of their precursors. Moreover, the accumulation of miRNA precursors in the hyl1 mutant gave us the opportunity to carry out 3’ and 5’ RACE experiments which revealed that some of these precursors are of unexpected length. The alignment of HYL1- dependent miRNA precursors to A. thaliana genomic sequences indicated the presence of introns in 12 out of 20 genes studied. Some of the characterized intron-containing pri-miRNAs undergo alternative splicing such as exon skipping or usage of alternative 5’ splice sites suggesting that this process plays a role in the regulation of miRNA biogenesis. In the hyl1 mutant intron-containing pri-miRNAs accumulate alongside spliced primiRNAs suggesting the recruitment of HYL1 into the miRNA precursor maturation pathway before their splicing occurs.

Embryos derived by somatic cell nuclear transfer (SCNT) produce few pregnancies that result in a live, healthy offspring. This has largely been attributed to the aberrant reprogramming of the somatic cell DNA used for cloning. In order to improve the efficiency of cloning there is a great deal of research needed to determine the role of proteins involved in early embryonic reprogramming. In addition, studies are needed to determine effects on somatic and embryonic cell development as a result of altering these proteins. In this study we investigate the use of RNA interference in bovine somatic cells and embryos to knock down the expression of DNA methyltransferase-1 (DNMT1), an enzyme responsible for maintenance methylation in mammalian cells. We designed our experiments to test whether or not knocking down the DNMT1 gene would lead to a decrease in global methylation. It is our hypothesis that using somatic cells with reduced methylation may be advantageous for increasing the efficiency of cloning via somatic cell nuclear transfer. To accomplish this task, we have designed an infectious non-replicating lentiviral vector capable of delivering a gene that produces a short hairpin RNA targeting the mRNA of DNMT1. The construct included a sequence coding for green fluorescent protein (GFP) that will allow us to identify cells expressing the hairpin as well as a region coding for neomycin resistance so we could select for a pure population of transgenic cells to use for analysis. Infecting bovine fetal fibroblast cells with genes encoding shRNAs that target DNMT1 was successful. Quantitative real time PCR analysis of DNMT1 mRNA suggests that our shRNAs are capable of an 80% knockdown. The protein blot of indicates up to 90% knockdown of DNMT1. Cells transduced twice with a high titer virus showed the highest knockdown of both DNMT1 mRNA and the protein. Analysis of immunolabeled cytosine methylaiton showed a global decrease in DNA methylation as a result of the DNMT1 knockdown. However, double transduced cells with a high knockdown percentage of DNMT1 mRNA and protein became hypermethylated. The second experiment was conducted to determine the effect of injecting small interfering RNAs (siRNAs) targeting DNMT1 into oocytes prior to parthenogenic activation. This experiment was designed to give us information on the survivability and epigenetic profile of early embryos with decreased DNMT1. Oocytes injected with siRNA targeting DNMT1 had little development past the 8-cell stage as compared to the sham injected oocytes. This treatment group also had decreased DNA methylation as determined by immunolabeling of methylated cytosine residues.