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131.
132.
Michaela S Lesjak Rosemarie Marchan Joanna D Stewart Eugen Rempel J?rg Rahnenführer Jan G Hengstler 《Cell Adhesion & Migration》2014,8(5):499-508
Endometrial carcinoma differential 3 (EDI3) was the first member of the glycerophosphodiesterase (GDE) protein family shown to be associated with cancer. Our initial work demonstrated that endometrial and ovarian cancer patients with primary tumors overexpressing EDI3 had a higher risk of developing metastasis and decreased survival. Further analysis indicated that EDI3 cleaves glycerophosphocholine to choline and glycerol-3-phosphate, increases the levels of active PKC, and enhances the migratory activity of tumor cells. Despite these initial findings, EDI3 remained mainly uncharacterized. Therefore, to obtain an overview of processes in which EDI3 may be involved, gene array analysis was performed using MCF-7 breast cancer cells after EDI3 knockdown compared with a non-targeting control siRNA. Several biological motifs were altered, including an enrichment of genes involved in integrin-mediated signaling. More specifically, silencing of EDI3 in MCF-7 and OVCAR-3 cells was associated with reduced expression of the key receptor subunit integrin β1, leading to decreased cell attachment and spreading accompanied by delayed formation of cell protrusions. To confirm these results, we stably overexpressed EDI3 in MCF-7 cells which led to elevated integrin β1 expression associated with enhanced cell attachment and spreading - two processes critical for metastasis. In conclusion, our data provide further insight into the role of EDI3 during cancer progression. 相似文献
133.
134.
McCabe R Bullenkamp J Hansson L Lauber C Martinez-Leal R Rössler W Salize HJ Svensson B Torres-Gonzalez F van den Brink R Wiersma D Priebe S 《PloS one》2012,7(4):e36080
Objective
Previous research has shown that a better therapeutic relationship (TR) predicts more positive attitudes towards antipsychotic medication, but did not address whether it is also linked with actual adherence. This study investigated whether the TR is associated with adherence to antipsychotics in patients with schizophrenia.Methods
134 clinicians and 507 of their patients with schizophrenia or a related psychotic disorder participated in a European multi-centre study. A logistic regression model examined how the TR as rated by patients and by clinicians is associated with medication adherence, adjusting for clinician clustering and symptom severity.Results
Patient and clinician ratings of the TR were weakly inter-correlated (rs = 0.13, p = 0.004), but each was independently linked with better adherence. After adjusting for patient rated TR and symptom severity, each unit increase in clinician rated TR was associated with an increase of the odds ratio of good compliance by 65.9% (95% CI: 34.6% to 104.5%). After adjusting for clinician rated TR and symptom severity, for each unit increase in patient rated TR the odds ratio of good compliance was increased by 20.8% (95% CI: 4.4% to 39.8%).Conclusions
A better TR is associated with better adherence to medication among patients with schizophrenia. Patients'' and clinicians'' perspectives of the TR are both important, but may reflect distinct aspects. 相似文献135.
H Korkaya GI Kim A Davis F Malik NL Henry S Ithimakin AA Quraishi N Tawakkol R D'Angelo AK Paulson S Chung T Luther HJ Paholak S Liu KA Hassan Q Zen SG Clouthier MS Wicha 《Molecular cell》2012,47(4):570-584
Although inactivation of the PTEN gene has been implicated in the development of resistance to the HER2 targeting antibody trastuzumab, the mechanisms mediating this resistance remain elusive. We generated trastuzumab resistant cells by knocking down PTEN expression in HER2 overexpressing breast cancer cell lines and demonstrate that development of trastuzumab resistance in these cells is mediated by activation of an IL6 inflammatory feedback loop leading to expansion of the cancer stem cell (CSC) population. Long term trastuzumab treatment generates highly enriched CSCs which display an EMT phenotype secreting over 100-fold more IL6 than parental cells. An IL6 receptor antibody interrupted this inflammatory feedback loop reducing the cancer stem cell population resulting in decreased tumor growth and metastasis in mouse xenographs. These studies demonstrate that trastuzumab resistance may be mediated by an IL6 inflammatory loop and suggest that blocking this loop may provide alternative strategy to overcome trastuzumab resistance. 相似文献
136.
137.
Eric D. Boyden A. Belinda Campos-Xavier Sebastian Kalamajski Trevor L. Cameron Philippe Suarez Goranka Tanackovic Generoso Andria Diana Ballhausen Michael D. Briggs Claire Hartley Daniel H. Cohn H. Rosemarie Davidson Christine Hall Shiro Ikegawa Pierre-Simon Jouk Rainer König André Megarbané Gen Nishimura Luisa Bonafé 《American journal of human genetics》2012,90(1):170
138.
The present study aims at providing standard values for the exploration type (ET)-specific quantification of extramatrical
mycelium (EMM) of ectomycorrhizal fungi applicable to ecological field studies. These values were established from mycelial
systems of ectomycorrhizae (ECM) synthesized in rhizotrons with near-to-natural peat substrate. Based on image analysis, the
“Specific Potential Mycelial Space Occupation” (sPMSO), i.e. the ET-specific complete area that is covered by the EMM systems
(mm2 cm−1 ECM−1), and the “Specific Actual Mycelial Space Occupation” (sAMSO), i.e. the projection area of mycelial systems (mm2 cm−1 ECM−1), were analyzed as an extension of a previously described approach. The “Specific Extramatrical Mycelial Length” (sEML) [m
cm−1 ECM−1] and the “Specific Extramatrical Mycelial Biomass” (sEMB) (μg cm−1 ECM−1) were calculated for each of the ET via the proportion of hyphal projected area, hyphal length and biomass, the latter two
being derived from previous measurements on Piloderma croceum, a “Medium-Distance” (MD)-ET. Both sPMSO and sAMSO were highest for the “Long-Distance” (LD)-ET, whereas those of the “Short-Distance”
(SD)-ET and MD-ET were similar, although showing high variation. In contrast, mycelial density per occupied area of the MD-ET
was twice as high as that of the LD-ET. Proportional to the sAMSO, the EMM length and biomass differed considerably between
the three ET with values of the MD-ET being 1.9 times higher than those of SD-ET, and those of the LD-ET being 15 times higher
than those of the SD-ET. These standards in relation to ECM length may ease quantification of mycelial space occupation and
biomass in a relatively simple way. Thereby, the ET-specific contribution of EMM can be distinguished—also of non-cultivable
species—and up-scaling to large-scale estimation of cost/benefit relations is possible. 相似文献
139.
Villareal VA Pilpa RM Robson SA Fadeev EA Clubb RT 《The Journal of biological chemistry》2008,283(46):31591-31600
Staphylococcus aureus scavenges heme-iron from host hemoproteins using iron-regulated surface determinant (Isd) proteins. IsdC is the central conduit through which heme is passed across the cell wall and binds this molecule using a NEAr Transporter (NEAT) domain. NMR spectroscopy was used to determine the structure of IsdC in complex with a heme analog, zinc-substituted protoporphyrin IX (ZnPPIX). The backbone coordinates of the ensemble of conformers representing the structure exhibit a root mean square deviation to the mean structure of 0.53 +/- 0.11 angstroms. IsdC partially buries protoporphyrin within a large hydrophobic pocket that is located at the end of its beta-barrel structure. The central metal ion of the analog adopts a pentacoordinate geometry in which a highly conserved tyrosine residue serves as a proximal ligand. Consistent with the structure and its role in heme transfer across the cell wall, we show that IsdC weakly binds heme (K(D) = 0.34 +/- 0.12 microm) and that ZnPPIX rapidly dissociates from the protein at a rate of 126 +/- 30 s(-1). NMR studies of the apo-form of IsdC reveal that a 3(10) helix within the binding pocket undergoes a flexible to rigid transition as heme is captured. This structural plasticity may increase the efficiency of heme transfer across the cell wall by facilitating protein-protein interactions between apoIsdC and upstream hemoproteins. 相似文献
140.
Pilpa RM Fadeev EA Villareal VA Wong ML Phillips M Clubb RT 《Journal of molecular biology》2006,360(2):435-447
During infections the pathogen Staphylococcus aureus procures the essential nutrient iron from its host using iron-regulated surface determinant (Isd) proteins, which scavenge heme bound iron from host hemoproteins. Four Isd proteins are displayed in the cell wall, where they function as receptors for host proteins and heme. Each of the receptors contains one or more copies of a recently discovered domain called NEAT (NEAr Transporter) that has been shown to mediate protein binding. Here we report the three-dimensional solution structure of the NEAT domain from the IsdH/HarA protein, which is the hemoglobin receptor in the Isd system. This is the first structure of a NEAT domain and reveals that they adopt a beta sandwich fold that consists of two five-stranded antiparallel beta sheets. Although unrelated at the primary sequence level, our results indicate that NEAT domains belong to the immunoglobulin superfamily. Binding studies indicate that two IsdH/HarA NEAT domains bind a single molecule of methemoglobin, while the distantly related NEAT domain from the S. aureus IsdC protein binds only heme. A comparison of their primary sequences in light of the new structure is used to predict the hemoglobin and heme binding surfaces on NEAT domains. 相似文献