Promoter hypermethylation of the SFRP2 gene is a high-frequent alteration and tumor-specific epigenetic marker in human breast cancer

<p>Abstract</p> <p>Background</p> <p>We have previously reported that expression of the Wnt antagonist genes <it>SFRP1 </it>and <it>SFRP5 </it>is frequently silenced by promoter hypermethylation in breast cancer. SFRP2 is a further Wnt inhibitor whose expression was recently found being downregulated in various malignancies. Here we investigated whether SFRP2 is also implicated in human breast cancer, and if so whether <it>SFRP2 </it>promoter methylation might serve as a potential tumor biomarker.</p> <p>Methods</p> <p>We analyzed <it>SFRP2 </it>mRNA expression and <it>SFRP2 </it>promoter methylation in 10 breast cell lines, 199 primary breast carcinomas, 20 matched normal breast tissues and 17 cancer-unrelated normal breast tissues using RT-PCR, realtime PCR, methylation-specific PCR and Pyrosequencing, respectively. SFRP2 protein expression was assessed by immunohistochemistry on a tissue microarray. Proliferation assays after transfection with an <it>SFRP2 </it>expression vector were performed with mammary MCF10A cells. Statistical evaluations were accomplished with SPSS 14.0 software.</p> <p>Results</p> <p>Of the cancerous breast cell lines, 7/8 (88%) lacked <it>SFRP2 </it>mRNA expression due to <it>SFRP2 </it>promoter methylation (<it>P </it>< 0.001). <it>SFRP2 </it>expression was substantially restored in most breast cell lines after treatment with 5-aza-2'-deoxycytidine and trichostatin A. In primary breast carcinomas SFRP2 protein expression was strongly reduced in 93 of 125 specimens (74%). <it>SFRP2 </it>promoter methylation was detected in 165/199 primary carcinomas (83%) whereas all cancer-related and unrelated normal breast tissues were not affected by <it>SFRP2 </it>methylation. <it>SFRP2 </it>methylation was not associated with clinicopathological factors or clinical patient outcome. However, loss of SFRP2 protein expression showed a weak association with unfavorable patient overall survival (<it>P </it>= 0.071). Forced expression of <it>SFRP2 </it>in mammary MCF10A cells substantially inhibited proliferation rates (<it>P </it>= 0.045).</p> <p>Conclusion</p> <p>The <it>SFRP2 </it>gene is a high-frequent target of epigenetic inactivation in human breast cancer. Its methylation leads to abrogation of <it>SFRP2 </it>expression, conferring a growth advantage to epithelial mammary cells. This altogether supports a tumor suppressive function of <it>SFRP2</it>. Although clinical patient outcome was not associated with <it>SFRP2 </it>methylation, the high frequency of this epimutation and its putative specificity to neoplastic cells may qualify <it>SFRP2 </it>promoter methylation as a potential candidate screening marker helping to improve early breast cancer detection.</p

DEEP—A tool for differential expression effector prediction

High-throughput methods for measuring transcript abundance, like SAGE or microarrays, are widely used for determining differences in gene expression between different tissue types, dignities (normal/malignant) or time points. Further analysis of such data frequently aims at the identification of gene interaction networks that form the causal basis for the observed properties of the systems under examination. To this end, it is usually not sufficient to rely on the measured gene expression levels alone; rather, additional biological knowledge has to be taken into account in order to generate useful hypotheses about the molecular mechanism leading to the realization of a certain phenotype

Dynamics and complexity of body temperature in preterm infants nursed in incubators

Poor control of body temperature is associated with mortality and major morbidity in preterm infants. We aimed to quantify its dynamics and complexity to evaluate whether indices from fluctuation analyses of temperature time series obtained within the first five days of life are associated with gestational age (GA) and body size at birth, and presence and severity of typical comorbidities of preterm birth.; We recorded 3h-time series of body temperature using a skin electrode in incubator-nursed preterm infants. We calculated mean and coefficient of variation of body temperature, scaling exponent alpha (Talpha) derived from detrended fluctuation analysis, and sample entropy (TSampEn) of temperature fluctuations. Data were analysed by multilevel multivariable linear regression.; Data of satisfactory technical quality were obtained from 285/357 measurements (80%) in 73/90 infants (81%) with a mean (range) GA of 30.1 (24.0-34.0) weeks. We found a positive association of Talpha with increasing levels of respiratory support after adjusting for GA and birth weight z-score (p&lt;0.001; R2 = 0.38).; Dynamics and complexity of body temperature in incubator-nursed preterm infants show considerable associations with GA and respiratory morbidity. Talpha may be a useful marker of autonomic maturity and severity of disease in preterm infants

Sigh-induced changes of breathing pattern in preterm infants

Sighs are thought to play an important role in control of breathing. It is unclear how sighs are triggered, and whether preterm birth and lung disease influence breathing pattern prior to and after a sigh in infants. To assess whether frequency, morphology, size, and short-term variability in tidal volume (VT) before, during, and after a sigh are influenced by gestational age at birth and lung disease (bronchopulmonary dysplasia, BPD) in former preterm infants and healthy term controls measured at equivalent postconceptional age (PCA). We performed tidal breathing measurements in 143 infants during quiet natural sleep at a mean (SD) PCA of 44.8 (1.3) weeks. A total of 233 sighs were analyzed using multilevel, multivariable regression. Sigh frequency in preterm infants increased with the degree of prematurity and severity of BPD, but was not different from that of term controls when normalized to respiratory rate. After a sigh, VT decreased remarkably in all infants (paired t-test: P &lt; 0.001). There was no major effect of prematurity or BPD on various indices of sigh morphology and changes in VT prior to or after a sigh. Short-term variability in VT modestly increased with maturity at birth and infants with BPD showed an earlier return to baseline variability in VT following a sigh. In early infancy, sigh-induced changes in breathing pattern are moderately influenced by prematurity and BPD in preterm infants. The major determinants of sigh-related breathing pattern in these infants remain to be investigated, ideally using a longitudinal study design

Dispositivo de lectura de microarrays de tipo eléctrico y reutilizable

Dispositivo de lectura de microarrays de tipo eléctrico y reutilizable. El objeto principal de la presente invención es un dispositivo de lectura eléctrica de microarrays que se puede limpiar y volver a utilizar más de una vez. El dispositivo (1, 1’, 1”) de lectura de microarrays (6) tiene las siguientes partes: una base (2, 2’, 2”), que tiene unos medios de apoyo (3, 3’, 3”) para situar la superficie de test (7) del microarray (6) en paralelo a una superficie de lectura (4) de la base (2, 2’, 2”); una matriz de transductores (5, 5’, 5”), dispuestos sobre la superficie de lectura (4) de la base (2, 2’, 2”), que traducen una variación de una magnitud eléctrica o química en una variación de una magnitud eléctrica; y unos medios de lectura (10), conectados a los transductores (5, 5’, 5”), que interpretan las señales eléctricas de los transductores (5, 5’, 5”).Peer reviewedConsejo Superior de Investigaciones Científicas (España)A1 Solicitud de patentes con informe sobre el estado de la técnic

Увеличение интенсификации добычи углеводородов в условиях низких фильтрационно-емкостных свойств пласта и осложнениями во время эксплуатации скважин на примере Северо-Останинского нефтегазоконденсатного месторождения (Томская область)

Актуальность темы исследования заключается в оценке существующих мероприятий на месторождении по увеличению добываемых нефти, газа и конденсата из скважин длительного срока эксплуатации, их экономической эффективности, а также разработка новых методов, направленных на оптимизацию и восстановление скважин, находящихся в простое и не удовлетворяющих нижнему пределу рентабельности. Целью данной работы является анализ эффективности методов по интенсификации на Северо-Останинском месторождении и применении метода КГРП с помощью технологии "Viscoelastic Diverting Acid" в процессе добычи углеводородов и осложнениями, возникающими во время эксплуатации скважин.The relevance of a subject of a research consists in assessment of the existing actions on the field for increase got oil, gas and condensate from wells of long term of operation, their economic efficiency and also development of the new methods directed to optimization and restoration of the wells which are in idle time and not satisfying to the lower limit of profitability. The purpose of this work is the analysis of efficiency of methods on an intensification on the North Ostaninsky field and application of the AHF method by means of Viscoelastic Diverting Acid technology in the course of extraction of hydrocarbons and the complications arising during operation of wells

Dynamics of myelin content decrease in the rat stroke model

A majority of studies were usually focused on neuronal death after brain ischemia, however, stroke affects all cell types including oligodendrocytes that form myelin sheath in the CNS. Our study is focused on the changes of myelin content in ischemic core and neighbor structures in early terms (1, 3 and 10 days) after stroke. Stroke modeled with middle cerebral artery occlusion (MCAo) in 15 male rats that were divided in three groups by time-points after operation. Brain sections were histologically stained with Luxol Fast Blue (LFB) for myelin quantification. The significant demyelination was found in the ischemic core, corpus callosum, anterior commissure, whereas myelin content was increased in caudoputamen, internal capsule and piriform cortex compared with the contralateral hemisphere. The motor cortex showed a significant increase of myelin content on the 1st day and a significant decrease on the 3rd and 10th days after MCAo. These results suggest stroke influences myelination not only in ischemic core but also in distant structures

Abcg2 Overexpression Represents a Novel Mechanism for Acquired Resistance to the Multi-Kinase Inhibitor Danusertib in BCR-ABL-Positive Cells In Vitro

The success of Imatinib (IM) therapy in chronic myeloid leukemia (CML) is compromised by the development of IM resistance and by a limited IM effect on hematopoietic stem cells. Danusertib (formerly PHA-739358) is a potent pan-aurora and ABL kinase inhibitor with activity against known BCR-ABL mutations, including T315I. Here, the individual contribution of both signaling pathways to the therapeutic effect of Danusertib as well as mechanisms underlying the development of resistance and, as a consequence, strategies to overcome resistance to Danusertib were investigated. Starting at low concentrations, a dose-dependent inhibition of BCR-ABL activity was observed, whereas inhibition of aurora kinase activity required higher concentrations, pointing to a therapeutic window between the two effects. Interestingly, the emergence of resistant clones during Danusertib exposure in vitro occurred considerably less frequently than with comparable concentrations of IM. In addition, Danusertib-resistant clones had no mutations in BCR-ABL or aurora kinase domains and remained IM-sensitive. Overexpression of Abcg2 efflux transporter was identified and functionally validated as the predominant mechanism of acquired Danusertib resistance in vitro. Finally, the combined treatment with IM and Danusertib significantly reduced the emergence of drug resistance in vitro, raising hope that this drug combination may also achieve more durable disease control in vivo