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The role of tetranectin in human breast MCF-7cancer cell line
No full text乳癌是全球女性中最常見的癌症種類。尤其近年來由於女性月經初潮提早發生，導致乳癌發病年齡層有年輕化的傾向。此情況不僅在全球，在台灣也有相同的趨勢。因此，乳癌對於婦女健康是ㄧ重大問題而不容忽視。先前研究指出tetranectin (TN)可做為多項人類腫瘤之可靠生物標記，包括乳癌、卵巢癌、口腔癌和膀胱癌…等等。正常情況下，TN在人體血漿中維持一定之濃度。相較於健康者，研究發現罹癌者會出現TN顯著降低的情況，並且又與乳癌患者的病癒存活 (disease-free survivl)及整體存活 (overall survival)有顯著的相關性。低濃度TN則為乳癌轉移的高危險指標，並且在乳腺腫瘤區域胞外基質 (extracellular matrix)表現出更強烈的免疫反應。因此，本研究的目的乃在釐清TN於乳癌細胞株中的功能及其分子機制。
首先，我們於非腫瘤乳腺上皮細胞株MCF10A，三類乳腺癌細胞株 (MCF7、MDA-MB-231和SKBR3)與乳腺導管上皮細胞株BT474中，分別比較TN的蛋白質表現量。結果顯示，在上述之乳癌細胞株中，除MCF10A外，TN皆可在全細胞萃取質 (whole-cell lysates) 和細胞培養液 (conditioned medium)中被偵測到。此外，我們也構築Myc-His-標記 (tagged) TN、TN-綠螢光 (GFP)融合蛋白或去訊息片段 (signal peptide-deficient-)TN-綠螢光之質體DNA載體，再分別將其轉染至MCF7細胞以分析受TN所影響的細胞功能。結果證實於軟洋菜膠 (soft agar)中培養時，全長(full-length) TN皆可增加細胞的非貼附性生長 (anchorage independent growth)，而不影響細胞存活率 (cell viability)。更有甚者，我們亦發現全段TN可顯著增進細胞的活動力 (cell motility)；然而，卻不見於去訊息片段者；此顯示TN於細胞運動中扮演胞外刺激因子的角色。
綜合上述，本研究中發現，TN表現於乳癌細胞株而非正常乳腺上皮細胞中。然而在MCF7細胞株中過量表現TN，可增加細胞活動及非貼附性生長，卻不影響細胞的存活。這些功能上的影響支持TN能在乳腺癌腫瘤的發展中發揮重要作用之假說。至於TN參與腫瘤發展的分子機制仍有待澄清。Breast cancer is the most common type of cancer in the females worldwide. In recent years, early onset of menarche leads to an increase in the incidence of such cancer in younger woman populations of the world, including Taiwan. Therefore, breast cancer has become a serious health issue for women. Tetranectin (TN) has been found to be a reliable biomarker in certain human carcinoma, including breast cancer, ovary cancer, oral cancer and bladder cancer. Consistently, TN is related to the disease-free and overall survival of breast cancer. Low TN concentrations in human plasma were reported as a high-risk factor for breast cancer metastasis. Interestingly, there has also been shown a strong immunoreactivity in the extracellular matrix associated with breast tumor malignancy. Thus, the purpose of this study was to elucidate the cellular functions of TN and the underlying mechanisms in breast cancer cell line.
First, we compared the protein expression of TN in non-tumorigenic epithelial cell line MCF10A, three breast adenocarcinoma cell lines (MCF7, MDA-MB-231 and SKBR3), and the breast ductal carcinoma cell line BT474, and found that TN was detected in both the whole-cell lysates and conditioned media of all breast cancer cell lines, except MCF10A. We then generated the expression constructs of Myc-His-tagged or GFP-fused full-length and signal peptide-deficient TN and transfected each into MCF7 cells to analyze TN-modulated cellular functions. Our results indicate that TN overexpression increased anchorage independent growth in a soft agar assay without affecting cell viability. Interestingly, we also found that TN prominently promoted cell motility, which was not seen for the signal peptide-deficient TN, indicating a role of TN in modulating cell movement is be an extracellular stimulator.
In conclusion, we demonstrated in this study that TN is normally up-regulated in breast cancer cell lines, but not in normal breast epithelial cells. When overexpressed, TN increases cell motility and anchorage independent growth in MCF7cell, without affecting cell survival. These support the hypothesis that TN plays an important role in tumor development of breast cancer. Nevertheless, the molecular mechanisms underlying TN-mediated tumor progression remain to be elucidated
Our Beautiful Planet
No full textJournalists from around the world report on environmental problems in their regions, with an emphasis on how pollution and a failure to protect natural resources can have a global impact. Topics discussed include pollution from industrial waste, pesticides, and automobile exhaust, deforestation, soil ruination and degradation, destruction of rainforests, global warming, species extinction, environmental education, recycling, and salvage ethnobotany. Includes reporting from host Lloyd Bridges, Yoriko Mekata (NHK- Japan) , Stuart McLean (TVO- Canada), Netpreeya Musigchai (TVT- Thailand), Rhoda Roberts (SBS- Australia), Sue Kopen (MPT-U nited States), Joachim Bublath (ZDF- Germany), Yang Shiow-Jiuan (TTV- Taiwan), and Chien Yu-Hsin (EPA Administrator
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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