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1.
PeerJ ; 8: e9567, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32995073

RESUMO

MicroRNAs (miRNAs) are short, non-coding, single-strand RNA molecules that act as regulators of gene expression in plants and animals. In 2012, the first evidence was found that plant miRNAs could enter the bloodstream through the digestive tract. Since then, there has been an ongoing discussion about whether miRNAs from the diet are transferred to blood, accumulate in tissues, and regulate gene expression. Different research groups have tried to replicate these findings, using both plant and animal sources. Here, we review the evidence for and against the transfer of diet-derived miRNAs from plants, meat, milk and exosome and their assimilation and putative molecular regulation role in the consuming organism. Some groups using both miRNAs from plant and animal sources have claimed success, whereas others have not shown transfer. In spite of the biological barriers that may limit miRNA transference, several diet-derived miRNAs can transfer into the circulating system and targets genes for transcription regulation, which adds arguments that miRNAs can be absorbed from the diet and target specific genes by regulating their expression. However, many other studies show that cross-kingdom transfer of exogenous miRNAs appears to be insignificant and not biologically relevant. The main source of controversy in plant studies is the lack of reproducibility of the findings. For meat-derived miRNAs, studies concluded that the miRNAs can survive the cooking process; nevertheless, our evidence shows that the bovine miRNAs are not transferred to human bloodstream. The most important contributions and promising evidence in this controversial field is the transference of milk miRNAs in exosomes and the finding that plant miRNAs in beebread regulate honeybee caste development, and cause similar changes when fed to Drosophila. MiRNAs encapsulated in exosomes ensure their stability and resistance in the harsh conditions presented in milk, bloodstream, and gastrointestinaltract to reinforce the idea of transference. Regardless of the model organism, the idea of source of miRNAs, or the approach-bioinformatics or in vivo-the issue of transfer of miRNAs from the diet remains in doubt. Our understanding of the cross-kingdom talk of miRNAs needs more research to study the transfer of "xenomiRs" from different food sources to complement and expand what we know so far regarding the interspecies transfer of miRNAs.

2.
Oncol Lett ; 11(6): 3563-3570, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27284356

RESUMO

MicroRNAs (miRNAs/miRs) are a family of small, endogenous and evolutionarily-conserved non-coding RNAs that are involved in the regulation of several cellular and functional processes. miRNAs can act as oncogenes or tumor suppressors in all types of cancer, and could be used as prognostic and diagnostic biomarkers. Databases and computational algorithms are behind the majority of the research performed on miRNAs. These tools assemble and curate the relevant information on miRNAs and present it in a user-friendly manner. The current review presents 14 online databases that address every aspect of miRNA cancer research. Certain databases focus on miRNAs and a particular type of cancer, while others analyze the behavior of miRNAs in different malignancies at the same time. Additional databases allow researchers to search for mutations in miRNAs or their targets, and to review the naming history of a particular miRNA. All these databases are open-access, and are a valuable tool for those researchers working with these molecules, particularly those who lack access to an advanced computational infrastructure.

3.
Cancer Biomark ; 15(3): 299-310, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26406572

RESUMO

BACKGROUND: Acute lymphoblastic leukemia (ALL) is a highly diverse disease characterized by cytogenetic and molecular abnormalities, including altered microRNA (miRNA) expression signatures. AIM: We perform and validate a plasma miRNA expression profiling to identify potential miRNA involved in leukemogenesis METHODS: MiRNA expression profiling assay was realized in 39 B-ALL and 7 normal control plasma samples using TaqMan Low Density Array (TLDA) plates on Applied Biosystems 7900 HT Fast Real-Time PCR System. MiRNA validation was done for six miRNA differentially expressed by quantitative real-time PCR. RESULTS: Seventy-seven circulating miRNA differentially expressed: hsa-miR-511, -222, and -34a were overexpressed, whereas hsa-miR-199a-3p, -223, -221, and -26a were underexpressed (p values < 0.005 for both sets). According to operating characteristic curve analysis, hsa-miR-511 was the most valuable biomarker for distinguishing B-ALL from normal controls, with an area under curve value of 1 and 100% for sensitivity, and specificity respectively. CONCLUSIONS: Measuring circulating levels of specific miRNA implicated in regulation of cell differentiation and/or cell proliferation such as hsa-miRNA-511, offers high sensitivity and specificity in B-ALL detection and may be potentially useful for detection of disease progression, as indicator of therapeutic response, and in the assessment of biological and/or therapeutic targets for patients with B-ALL.


Assuntos
Biomarcadores Tumorais/sangue , MicroRNAs/sangue , Leucemia-Linfoma Linfoblástico de Células Precursoras B/sangue , Adolescente , Adulto , Idoso , Diferenciação Celular/fisiologia , Proliferação de Células/fisiologia , Criança , Pré-Escolar , Progressão da Doença , Feminino , Perfilação da Expressão Gênica , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase em Tempo Real , Adulto Jovem
4.
Methods Mol Biol ; 1165: 71-80, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24839019

RESUMO

MicroRNAs (miRNAs) are important regulatory molecules involved in disease pathogenesis. miRNAs are very stable in bodily fluids and can be detected in serum, plasma, saliva, and urine, among other fluids. Several studies have demonstrated the usefulness of serum miRNAs as potential biomarkers for detecting and monitoring cancer progression. Here, we describe in detail the experiment protocol we used to profile miRNA expression in the serum of breast cancer patients, including RNA extraction from serum, RT-qPCR quantification, and analysis of the deregulated miRNAs. Detection of circulating miRNAs may be a useful, noninvasive diagnostic tool for breast cancer.


Assuntos
Biomarcadores Tumorais/sangue , Análise Química do Sangue/métodos , Neoplasias da Mama/sangue , MicroRNAs/sangue , Regulação Neoplásica da Expressão Gênica , Humanos , MicroRNAs/genética , MicroRNAs/isolamento & purificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa
5.
PLoS One ; 8(7): e68202, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23874540

RESUMO

BACKGROUND: Entamoeba histolytica is the causative agent of amebiasis, a disease that is a major source of morbidity and mortality in the developing world. MicroRNAs (miRNAs) are a large group of non-coding RNAs that play important roles in regulating gene expression and protein translation in animals. Genome-wide identification of miRNAs is a critical step to facilitating our understanding of genome organization, genome biology, evolution, and post-transcriptional regulation. METHODOLOGY/PRINCIPAL FINDINGS: We sequenced a small RNA library prepared from a culture of trophozoites of Entamoeba histolytica Strain HM1-IMSS using a deep DNA sequencing approach. Deep sequencing yielded 16 million high-quality short sequence reads containing a total of 5 million non-redundant sequence reads. Based on a bioinformatics pipeline, we found that only 0.5% of these non-redundant small RNA reads were a perfect match with the drafted E. histolytica genome. We did not find miRNA homologs in plant or animal miRNAs. We discovered 199 new potential Entamoeba histolytica miRNAs. The expression and sequence of these Ehi-miRNAs were further validated through microarray by µParaflo Microfluidic Biochip Technology. Ten potential miRNAs were additionally confirmed by real time RT-PCR analysis. Prediction of target genes matched 32 known genes and 34 hypothetical genes. CONCLUSIONS/SIGNIFICANCE: These results show that there is a number of regulatory miRNAs in Entamoeba histolytica. The collection of miRNAs in this parasite could be used as a new platform to study genomic structure, gene regulation and networks, development, and host-parasite interactions.


Assuntos
Entamoeba histolytica/genética , MicroRNAs/genética , Análise por Conglomerados , Bases de Dados Genéticas , Genes de Protozoários/genética , MicroRNAs/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase em Tempo Real , Reprodutibilidade dos Testes , Análise de Sequência de RNA , Trofozoítos/metabolismo
6.
Dis Markers ; 34(3): 163-9, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23334650

RESUMO

MicroRNAs (miRNAs) are a class of small, non-coding RNA molecules that can regulate gene expression, thereby affecting crucial processes in cancer development. miRNAs offer great potential as biomarkers for cancer detection because of their remarkable stability in blood and their characteristic expression in different diseases. We investigated whether quantitative RT-PCR miRNA profiling on serum could discriminate between breast cancer patients and healthy controls. We performed miRNA profiling on serum from breast cancer patients, followed by construction of ROC (Receiver Operating Characteristic) curves to determine the sensitivity and specificity of the assay. We found that seven miRNAs (miR-10b, miR-21, miR-125b, miR-145, miR-155 miR-191 and miR-382) had different expression patterns in serum of breast cancer patients compared to healthy controls. ROC curve analyses revealed that three serum miRNAs could be valuable biomarkers for distinguishing BC from normal controls. Additionally, a combination of ROC curve analyses of miR-145, miR-155 and miR-382 showed better sensitivity and specificity of our assay. miRNA profiling in serum has potential as a novel method for breast cancer detection in the Mexican population.


Assuntos
Biomarcadores Tumorais/sangue , Neoplasias da Mama/diagnóstico , Perfilação da Expressão Gênica , MicroRNAs/sangue , RNA Mensageiro/genética , Adulto , Idoso , Neoplasias da Mama/sangue , Neoplasias da Mama/patologia , Estudos de Casos e Controles , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Curva ROC , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sensibilidade e Especificidade
7.
Asia Pac J Clin Oncol ; 9(1): 53-9, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22898264

RESUMO

AIMS: To develop new biomarkers for early detection and to inform effective clinical management of breast cancer. METHODS: Real-time polymerase chain reaction was used to profile microRNA (miRNA) in tumor tissue from 50 breast cancer patients using non-tumor breast tissue from each patient as a control. We have focussed on three miRNA; miR-21, miR-125b and miR-191, all of which have been implicated in breast cancer with either proven or predicted target genes involved in critical cancer-associated cellular pathways. RESULTS: Upregulation of miR-21 and miR-191 and downregulation of miR-125b, was found in breast cancer tissue. Combined expression analysis of miR-125b/miR-191 increased sensitivity to 100% and specificity to 94% while miR-21/miR-191 increased to 92% and 100%, respectively. Therefore, combination of two miRNA gives a better prediction than individual miRNA. CONCLUSIONS: We could differentiate between breast cancer and adjacent non-tumor breast tissue as a control with a high degree of sensitivity and specificity in the Mexican population using a combined expression analysis of only two miRNA. These observations, although a proof of principle finding at this time, show that a combined expression profile of two miRNA (miR-125b/miR-191 and miR-21/miR-191) can discriminate between breast cancer and non-tumor tissue with high specificity and sensitivity.


Assuntos
Neoplasias da Mama/genética , Mama/metabolismo , Carcinoma Ductal de Mama/genética , Carcinoma Lobular/genética , MicroRNAs/genética , Adulto , Idoso , Biomarcadores Tumorais/genética , Mama/patologia , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Carcinoma Lobular/patologia , Estudos de Casos e Controles , Feminino , Seguimentos , Regulação Neoplásica da Expressão Gênica , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , RNA Mensageiro/genética , Curva ROC , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa
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