Uchino M.,Matrix Research Inc |
Kojima H.,Matrix Research Inc |
Kojima H.,Atto Corporation |
Wada K.,Matrix Research Inc |
And 8 more authors.
BMC Cancer | Year: 2010
Background: In breast cancer cells, the metastatic cell state is strongly correlated to epithelial-to-mesenchymal transition (EMT) and the CD44+/CD24-stem cell phenotype. However, the MCF-7 cell line, which has a luminal epithelial-like phenotype and lacks a CD44+/CD24-subpopulation, has rare cell populations with higher Matrigel invasive ability. Thus, what are the potentially important differences between invasive and non-invasive breast cancer cells, and are the differences related to EMT or CD44/CD24 expression?Methods: Throughout the sequential selection process using Matrigel, we obtained MCF-7-14 cells of opposite migratory and invasive capabilities from MCF-7 cells. Comparative analysis of epithelial and mesenchymal marker expression was performed between parental MCF-7, selected MCF-7-14, and aggressive mesenchymal MDA-MB-231 cells. Furthermore, using microarray expression profiles of these cells, we selected differentially expressed genes for their invasive potential, and performed pathway and network analysis to identify a set of interesting genes, which were evaluated by RT-PCR, flow cytometry or function-blocking antibody treatment.Results: MCF-7-14 cells had enhanced migratory and invasive ability compared with MCF-7 cells. Although MCF-7-14 cells, similar to MCF-7 cells, expressed E-cadherin but neither vimentin nor fibronectin, β-catenin was expressed not only on the cell membrane but also in the nucleus. Furthermore, using gene expression profiles of MCF-7, MCF-7-14 and MDA-MB-231 cells, we demonstrated that MCF-7-14 cells have alterations in signaling pathways regulating cell migration and identified a set of genes (PIK3R1, SOCS2, BMP7, CD44 and CD24). Interestingly, MCF-7-14 and its invasive clone CL6 cells displayed increased CD44 expression and downregulated CD24 expression compared with MCF-7 cells. Anti-CD44 antibody treatment significantly decreased cell migration and invasion in both MCF-7-14 and MCF-7-14 CL6 cells as well as MDA-MB-231 cells.Conclusions: MCF-7-14 cells are a novel model for breast cancer metastasis without requiring constitutive EMT and are categorized as a "metastable phenotype", which can be distinguished from both epithelial and mesenchymal cells. The alterations and characteristics of MCF-7-14 cells, especially nuclear β-catenin and CD44 upregulation, may characterize invasive cell populations in breast cancer. © 2010 Uchino et al; licensee BioMed Central Ltd. Source
Kim B.,Sejong University |
Kim D.,Sejong University |
Han D.,Sejong University |
Lee N.-I.,Atto Corporation
Materials and Manufacturing Processes | Year: 2011
A new model of plasma etch processes is presented. The model was constructed by applying the backpropagation neural network and genetic algorithm (GA) to wavelet filtered data. During a plasma etching of oxide films, optical emission spectroscopy (OES) data were collected, and the etch responses measured include an etch rate, a selectivity, and a nonuniformity. Discrete and continuous wavelets were applied to filter OES data. Dimensionality of filtered OES data was then reduced by applying the principal component analysis with three variances of 100, 99, and 98%. For each response or each data variance, three types of model were constructed. In other words, a total of 54 models were built for comparison. For the discrete wavelet-filtered data, the optimized model errors are 252Å/min, 3.1, 0.51%, identified at 98, 99, and 99% for the etch rate, profile angle, and nonuniformity, respectively. For the continuous wavelet-filtered data, they are 329Å/min, 3.83, and 0.31%. Therefore, for the etch rate and selectivity, the discrete wavelet data yielded improved prediction. For the non-uniformity, the continuous wavelet data produced much better prediction than the discrete wavelet data. Compared to earlier models, improved prediction of the proposed model was demonstrated for all but the etch profile angle data. Copyright © Taylor & Francis Group, LLC. Source
Atto Co. | Date: 2010-07-28
Provided is a method of manufacturing a semiconductor device. In the method, after a thin liner is formed on a substrate on which a lower interconnection is formed, a silicon source is supplied to form a silicide layer under the liner by a reaction between the silicon source and the lower interconnection, and the silicide layer is nitrided and an etch stop layer is formed. Therefore, the lower interconnection is prevented from making contact with the silicon source, variations of the surface resistance of the lower interconnection can be prevented, and thus high-speed devices can be fabricated.
Atto Co. | Date: 2010-07-23
Provided are a deposition apparatus and a method of manufacturing a semiconductor device. In the method, a reaction chamber provided with a gaseous source supply unit and a liquid source supply unit is prepared, and an etch stop layer is formed on a substrate by using a gaseous source. Then, an interlayer insulation layer is formed on the etch stop layer by using a vaporized liquid source and a vaporized dopant source. In this way, the etch stop layer and the interlayer insulation layer are formed in-situ in the same reaction chamber.
Watanabe D.,Japanese National Research Institute of Brewing |
Ota T.,Atto Corporation |
Nitta F.,Atto Corporation |
Akao T.,Japanese National Research Institute of Brewing |
Shimoi H.,Japanese National Research Institute of Brewing
Journal of Bioscience and Bioengineering | Year: 2011
In small-scale sake brewing tests, progression of ethanol fermentation is examined by monitoring carbon dioxide emission using the Fermograph, an automated multi-channel gas monitor instrument. The Fermograph system enables automatic measurements of fermentation profiles with high accuracy, reproducibility, and resolution, and facilitates comprehensive and quantitative sake fermentation kinetic analyses. © 2011 The Society for Biotechnology, Japan. Source