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21.

Background

A recent epidemiological study demonstrated a reduced risk of lung cancer mortality in breast cancer patients using antiestrogens. These and other data implicate a role for estrogens in lung cancer, particularly nonsmall cell lung cancer (NSCLC). Approximately 61% of human NSCLC tumors express nuclear estrogen receptor β (ERβ); however, the role of ERβ and estrogens in NSCLC is likely to be multifactorial. Here we tested the hypothesis that proteins interacting with ERβ in human lung adenocarcinoma cells that respond proliferatively to estradiol (E2) are distinct from those in non-E2-responsive cells.

Methods

FLAG affinity purification of FLAG-ERβ-interacting proteins was used to isolate ERβ-interacting proteins in whole cell extracts from E2 proliferative H1793 and non-E2-proliferative A549 lung adenocarcinoma cell lines. Following trypsin digestion, proteins were identified using liquid chromatography electrospray ionization tandem mass spectrometry (LC-MS/MS). Proteomic data were analyzed using Ingenuity Pathway Analysis. Select results were confirmed by coimmunoprecipitation.

Results

LC-MS/MS identified 27 non-redundant ERβ-interacting proteins. ERβ-interacting proteins included hsp70, hsp60, vimentin, histones and calmodulin. Ingenuity Pathway Analysis of the ERβ-interacting proteins revealed differences in molecular and functional networks between H1793 and A549 lung adenocarcinoma cells. Coimmunoprecipitation experiments in these and other lung adenocarcinoma cells confirmed that ERβ and EGFR interact in a gender-dependent manner and in response to E2 or EGF. BRCA1 interacted with ERβ in A549 cell lines and in human lung adenocarcinoma tumors, but not normal lung tissue.

Conclusion

Our results identify specific differences in ERβ-interacting proteins in lung adenocarcinoma cells corresponding to ligand-dependent differences in estrogenic responses.
  相似文献   
22.
MethodologyWe interviewed sixty caregivers participating in a large survey on child health and nutrition. We conducted three waves of interviews with children’s primary caregivers in seventeen rural villages within four nationally-designated poverty counties in the southern part of Shaanxi Province.ResultsThe qualitative analysis reveals that poor complementary feeding practices are common across our sample. Information gathered from our interviews suggests that complementary feeding practices are impeded by two constraints: absence of understanding topics related to infant health and nutrition under caregivers, as well as inadequate sources of information on these topics. Poverty does not appear to constrain child feeding practices.ConclusionOur results uncover lack of proper knowledge on infant and child nutrition among rural caregivers in China. This situation causes them to fail incorporating micronutrient rich foods in their children''s diet. Age-appropriate complementary feeding can stimulate children’s physical and cognitive development, but in its absence it leads to iron-deficiency anemia. We suggest that steps be taken to educate caregivers to improve complementary feeding of their infants and children.  相似文献   
23.
Muscle tissue from 63 Synodontis zambezensis collected bimonthly in 2013 at Flag Boshielo Dam were analysed for metals and metalloids in a desktop human health risk assessment. The Hazard Quotient, based on a weekly meal of 67 g of fish muscle, exceeded the maximum acceptable level of one for lead, cobalt, cadmium, mercury, arsenic and selenium. The concentrations of these elements were higher in 2013 than those recorded in 2009 and 2012 in other fish species from Flag Boshielo Dam and these may pose a long-term health risk if consumed regularly by impoverished rural communities reliant on fish as a source of protein.  相似文献   
24.
The modelling and optimization of a process for the production of the medium chain length polyhydroxyalkanoate (mcl-PHA) by the bacterium Pseudomonas putida KT2440 when fed a synthetic fatty acid mixture (SFAM) was investigated. Four novel feeding strategies were developed and tested using a constructed model and the optimum one implemented in further experiments. This strategy yielded a cell dry weight of 70.6 g l−1 in 25 h containing 38% PHA using SFAM at 5 l scale. A phosphate starvation strategy was implemented to improve PHA content, and this yielded 94.1 g l−1 in 25 h containing 56% PHA using SFAM at 5 l scale. The process was successfully operated at 20 l resulting in a cell dry weight of 91.2 g l−1 containing 65% PHA at the end of a 25-h incubation.  相似文献   
25.
Calcium signaling is a key regulator of pathways important in tumor progression, such as proliferation and apoptosis. Most studies assessing altered calcium homeostasis in cancer cells have focused on alterations mediated through changes in cytoplasmic free calcium levels. Here, we show that basal-like breast cancers are characterized by an alteration in the secretory pathway calcium ATPase 1 (SPCA1), a calcium pump localized to the Golgi. Inhibition of SPCA1 in MDA-MB-231 cells produced pronounced changes in cell proliferation and morphology in three-dimensional culture, without alterations in sensitivity to endoplasmic reticulum stress induction or changes in global calcium signaling. Instead, the effects of SPCA1 inhibition in MDA-MB-231 cells reside in altered regulation of calcium-dependent enzymes located in the secretory pathway, such as proprotein convertases. Inhibition of SPCA1 produced a pronounced alteration in the processing of insulin-like growth factor receptor (IGF1R), with significantly reduced levels of functional IGF1Rβ and accumulation of the inactive trans-Golgi network pro-IGF1R form. These studies identify for the first time a calcium transporter associated with the basal-like breast cancer subtype. The pronounced effects of SPCA1 inhibition on the processing of IGF1R in MDA-MB-231 cells independent of alterations in global calcium signaling also demonstrate that some calcium transporters can regulate the processing of proteins important in tumor progression without major alterations in cytosolic calcium signaling. Inhibitors of SPCA1 may offer an alternative strategy to direct inhibitors of IGF1R and attenuate the processing of other proprotein convertase substrates important in basal breast cancers.  相似文献   
26.
K Barnes  A J Kenny 《Peptides》1988,9(1):55-63
Endopeptidase-24.11, an ectoenzyme with a key role in metabolizing peptides at cell surfaces, is present in the adenohypophysis. A specific polyclonal antibody to the endopeptidase has been used to explore its localization in cryostat sections of pig pituitary glands by an immunoperoxidase method. Immunoreactivity was symmetrically but not uniformly distributed over the anterior lobe, with the highest intensity a zone just beneath the capsule along the anterior surface. In detail, the staining was observed to be in the cell membrane, but in some cells a small area of intense paranuclear staining was also observed. Serial 5 micron sections were immunostained alternately for endopeptidase-24.11 and for pituitary proteohormone. Luteinizing hormone (LH), follicular stimulating hormone (FSH), thyrotropin, adrenocorticotropin, prolactin and growth hormone were studied in this way. It was possible to identify groups of cells in adjacent sections and a good correlation was observed for endopeptidase-24.11-immunoreactivity with that for LH and FSH. The association of the endopeptidase with gonadotrophs was confirmed by double labelling. No evidence of colocalization was observed with the other proteohormone antibodies. We conclude that among the cells of the adenohypophysis only the gonadotrophs express endopeptidase-24.11 and discuss the possible significance of this observation in regard to the termination of peptide signals, such as that of luteinizing hormone-releasing hormone (LHRH) acting at this site.  相似文献   
27.
Parkinson's disease (PD) is a common neurodegenerative movement disorder that affects increasing number of elderly in the world population. The disease is caused by a selective degeneration of dopaminergic neurons in the substantia nigra pars compacta with the molecular mechanism underlying this neurodegeneration still not fully understood. However, various studies have shown that mitochondrial dysfunction and abnormal protein aggregation are two of the major contributors for PD. In fact this notion has been supported by recent studies on genes that are linked to familial PD (FPD). For instance, FPD linked gene products such as PINK1 and parkin have been shown to play critical roles in the quality control of mitochondria, whereas α-synuclein has been found to be the major protein aggregates accumulated in PD patients. These findings suggest that further understanding of how dysfunction of these pathways in PD will help develop new approaches for the treatment of this neurodegenerative disorder.  相似文献   
28.
It has been argued that the limited genetic diversity and reduced allelic heterogeneity observed in isolated founder populations facilitates discovery of loci contributing to both Mendelian and complex disease. A strong founder effect, severe isolation, and substantial inbreeding have dramatically reduced genetic diversity in natives from the island of Kosrae, Federated States of Micronesia, who exhibit a high prevalence of obesity and other metabolic disorders. We hypothesized that genetic drift and possibly natural selection on Kosrae might have increased the frequency of previously rare genetic variants with relatively large effects, making these alleles readily detectable in genome-wide association analysis. However, mapping in large, inbred cohorts introduces analytic challenges, as extensive relatedness between subjects violates the assumptions of independence upon which traditional association test statistics are based. We performed genome-wide association analysis for 15 quantitative traits in 2,906 members of the Kosrae population, using novel approaches to manage the extreme relatedness in the sample. As positive controls, we observe association to known loci for plasma cholesterol, triglycerides, and C-reactive protein and to a compelling candidate loci for thyroid stimulating hormone and fasting plasma glucose. We show that our study is well powered to detect common alleles explaining ≥5% phenotypic variance. However, no such large effects were observed with genome-wide significance, arguing that even in such a severely inbred population, common alleles typically have modest effects. Finally, we show that a majority of common variants discovered in Caucasians have indistinguishable effect sizes on Kosrae, despite the major differences in population genetics and environment.  相似文献   
29.
A new virus, Mycoplasmatales virus-modicum 1 (MV-M1), was recovered from spontaneous plaques in lawns ofAcholeplasma modicum. Strain “mod” produced plaques onA. modicum strains but not on strains ofAcholeplasma laidlawii. Only MV-L3 of the three knownA. laidlawii viruses (MV-L1, MV-L2, and MV-L3) produced plaques onA. modicum. The MV-M1 virus was serologically distinct from the threeA. laidlawii viruses; filterable at 0.1 μm; partially sensitive to heat and Nonidet P-40; and chloroform labile. Spherical particles ranging from 105 to 160 nm were observed in electron micrographs of negatively stained preparations.  相似文献   
30.
Summary The host-parasite relationship of HeLa M cells artificially infected with a bovine species of Mycoplasma was studied by light microscopy, transmission electron microscopy and scanning electron microscopy. The use of morphometry to quantitate some of the findings was explored. The parasites were seen in locations extracellular to the cell surface. The detection of small numbers of organisms by light microscopy was well demonstrated by use of the fluorescent antibody technique. Scanning electron microscopy proved to be an excellent method for revealing the surface details of cell-parasite morphology. Ultra-thin sections showed that the parasites are aligned mostly parallel to the plasma membrane of the host cell but separated by a gap of 10 nm. Morphometry indicated an average of 69 organisms per cell surface occupying 1.7% of the surface area. An increase of 26% in diameter of the HeLa cells, possibly as a result of infection, was observed.The authors wish to thank Christiana Ulness and Andrea Erickson for expert technical assistance and Arnold Schmidt for the operation of the scanning electron microscope. This work was supported by grants from the U.S.P.H.S.: AI 09586, AI 10743, and AI 06720  相似文献   
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