RESUMEN
MicroRNAs (miRNAs) are posttranscriptional regulators of gene expression. They play an important role in various cellular processes such as apoptosis, differentiation, secretion, and proliferation. Embryonic stem cells (ESCs) are derived from the inner cell mass of the blastocyst stage of the embryo. miRNAs are critical factors for the self-renewal and differentiation of ESCs. In this review, we will focus on the role of miRNAs in the self-renewal and directional differentiation of ESCs. We will present the current knowledge on key points related to miRNA biogenesis and their function in ESCs.
Asunto(s)
Diferenciación Celular/fisiología , Células Madre Embrionarias Humanas/metabolismo , MicroARNs/metabolismo , Animales , Células Madre Embrionarias Humanas/citología , HumanosRESUMEN
Serum exosomal microRNAs (miRNAs) have received considerable attention as potential biomarkers for tumor diagnosis. Reverse transcriptionquantitative polymerase chain reaction (RTqPCR) is commonly used to detect miRNA expression levels in various types of cancer. One prerequisite for valid RTqPCR data is the correct normalization of miRNAs to stably expressed endogenous reference genes (RGs). The study of liver carcinoma resection requires the use of reliable RGs in order to assess the expression levels of serum exosomal target miRNAs. However, the assessment of RG suitability for optimum serum exosomal miRNA expression analysis has yet to be investigated. The present study investigated the expression stability of 10 candidate RGs. The candidate genes included eight miRNAs (miR16, miR103, miR191, let7a, miR26a, miR221, miR181a, and miR451) and two small RNAs (5S and U6). The stability values of the candidate genes were calculated using the following algorithms: geNorm, NormFinder, BestKeeper, and the comparative ΔCt method. The overall ranking obtained from these analyses revealed that miR221, let7a, and miR26a were appropriate internal RGs for analysis of serum miRNAs in patients with hepatocellular carcinoma. In addition, normalization with miR221 and let7a combined, as recommended by geNorm, or with miR26a, as recommended by NormFinder, increased the accuracy of interpretation of the target miRNA expression levels in hepatopathy studies.
Asunto(s)
Biomarcadores de Tumor/genética , Carcinoma Hepatocelular/sangre , Exosomas/genética , Perfilación de la Expresión Génica/normas , Neoplasias Hepáticas/sangre , MicroARNs/genética , Adulto , Biomarcadores de Tumor/sangre , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/cirugía , Exosomas/metabolismo , Femenino , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/cirugía , Masculino , MicroARNs/sangre , Persona de Mediana Edad , Reacción en Cadena en Tiempo Real de la Polimerasa , Estándares de Referencia , Reacción en Cadena de la Polimerasa de Transcriptasa InversaRESUMEN
Glioma pathogenesis related-2 (GLIPR-2) belongs to pathogenesis related-1 (PR-1) family whose function remains unknown. In our previous studies, GLIPR-2 was found to be a novel potent stimulator of epithelial-to-mesenchymal transition (EMT) in renal fibrosis which has been classified as type 2 EMT. However, whether GLIPR-2 could induce type 3 EMT in carcinogenesis needs further investigation. In this study, we showed that GLIPR-2 was expressed in hepatocellular carcinoma (HCC) tissues, hypoxia could upregulate the expression of GLIPR-2 in HepG2 and PLC/PRF/5 cells in vitro, overexpression of this protein promoted migration and invasion via EMT, knockdown of GLIPR-2 attenuated migration and invasion of HepG2 and PLC/PRF/5 cells in hypoxia. Moreover, extracellular signal-regulated kinases 1 and 2 (ERK1/2) are positively regulated by GLIPR-2. Taken together, we provide evidence for a hypoxia/GLIPR-2/EMT/migration and invasion axis in HCC cells and it provides novel insights into the mechanism of migration and invasion of hepatocellular carcinoma cells in hypoxia condition.
Asunto(s)
Carcinoma Hepatocelular/genética , Transición Epitelial-Mesenquimal/genética , Regulación Neoplásica de la Expresión Génica , Hipoxia/genética , Neoplasias Hepáticas/genética , Proteínas de la Membrana/genética , Carcinoma Hepatocelular/complicaciones , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Movimiento Celular , Células Hep G2 , Humanos , Hipoxia/complicaciones , Hipoxia/metabolismo , Hipoxia/patología , Neoplasias Hepáticas/complicaciones , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Proteínas de la Membrana/antagonistas & inhibidores , Proteínas de la Membrana/metabolismo , Proteína Quinasa 1 Activada por Mitógenos/antagonistas & inhibidores , Proteína Quinasa 1 Activada por Mitógenos/genética , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos/antagonistas & inhibidores , Proteína Quinasa 3 Activada por Mitógenos/genética , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/metabolismo , Transducción de SeñalRESUMEN
To investigate the expression of hPOT1 in the HeLa cell line and screen point mutations of hpot1 in different tumor tissues a two step osmotic method was used to extract nuclear proteins. EMSA was performed to determine the expression of hPOT1 in the HeLa cell line. PCR was also employed to amplify the exon14 sequence of the hpot1 gene in various of cancer tissues. A SV gel and PCR clean-up system was performed to enrich PCR products. DNAStar was used to analyse the exon14 sequence of the hpot1 gene. hPOT1 was expressed in the HeLa cell line and the signal was gradually enhanced as the amount of extracted nuclear proteins increased. The DNA fragment of exon14 of hpot1 was successfully amplified in the HeLa cell line and all cancer tissues, point mutations being observed in 2 out of 3 cases of endometrial cancer (66.7%) despite the hpot1 sequence being highly conserved. However, the sequence of hpot1 exon14 do not demonstrate point mutations in most cancer tissues. Since hPOT1 was expressed in HeLa cell and the probability of gene point variants was obviously higher in endometrial cancer than other cancers, it may be involved in the pathogenesis of gynecological cancers, especially in cervix and endometrium.
Asunto(s)
Neoplasias Endometriales/genética , Exones/genética , Neoplasias/genética , Mutación Puntual/genética , Proteínas de Unión a Telómeros/genética , Adulto , Anciano , Secuencia de Bases , Ensayo de Cambio de Movilidad Electroforética , Femenino , Células HeLa , Humanos , Persona de Mediana Edad , Datos de Secuencia Molecular , Pronóstico , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Complejo Shelterina , Tasa de SupervivenciaRESUMEN
Vascular endothelial cells are very sensitive to ionizing radiation, and it is important to develop effective prevent agents and measures in radiation exposure protection. In the present study, the protective effects of atorvastatin on irradiated human umbilical vein endothelial cells (HUVEC) and the possible mechanisms were explored. Cultured HUVEC were treated by atorvastatin at a final concentration of 10 µ mol/ml for 10 minutes, and then irradiated at a dose of 2 Gy or 25 Gy. Twenty-four hours after irradiation, apoptosis of HUVEC was monitored by flow cytometry, and the expression of thrombomodulin (TM) and protein C activation in HUVEC was respectively assessed by flow cytometry and spectrophotometry. After treatment with atorvastatin for 24 h, the rate of cell apoptosis decreased by 6% and 16% in cells irradiated with 2 Gy and 25 Gy, respectively. TM expression increased by 77%, 59%, and 61% in untreated cells, 2 Gy irradiation-treated cells, and 25 Gy irradiation-treated cells, respectively. The protein C levels in 2 Gy and 25 Gy irradiation-treated cells were reduced by 23% and 34% when compared with untreated cells, but up-regulated by 79% and 76% when compared with cells which were irradiated and treated with atorvastatin. In conclusion, these data indicate that atorvastatin exerts protective effects on irradiated HUVEC by reducing apoptosis by up-regulating TM expression and enhancing protein C activation in irradiated HUVEC.