8,494 research outputs found
Quantifying the FIR interaction enhancement in paired galaxies
The Catalog of Isolated Pairs of Galaxies in the Northern Hemisphere, by Karachentsev (1972), was studied and a well-matched comparison sample taken from the Catalog of Isolated Galaxies, by Karachentseva (1973), in order to quantify the enhanced FIR emission properties of interacting galaxies
Optimizing Virtual Machine I/O Performance in Virtualized Cloud by Differenciated-frequency Scheduling and Functionality Offloading
Many enterprises are increasingly moving their applications to private cloud environments or public cloud platforms. A key technology driving cloud computing is virtualization which can serve multiple VMs in one physical machine hence providing better management flexibility and significant savings in operational costs. However, one important consequence of virtualized hosts in the cloud is the negative impact it has on the I/O performance of the applications running in the VMs
STROMAL-EPITHELIAL INTERACTIONS MODULATE CROSS TALK BETWEEN PROLACTIN RECEPTOR AND HER2/NEU IN BREAST CANCER
The tumor microenvironment is a crucial factor in breast tumorigenesis. Tumor epithelial cells maintain 3D structure in tumor stroma and they interact with soluble factors secreted by stromal cells such as cancer associated fibroblasts (CAFs) or directly with the extracellular matrix (ECM). Recent studies have shown that the hormone prolactin (PRL) promotes the proliferation and survival of breast cancer cells in part via the transactivation of human epidermal growth factor receptor 2 (HER2), also known as Neu in rodents. A PRL receptor (PRLR) antagonist, G129R, has been demonstrated not only to be able to directly inhibit PRLR activation but also indirectly inhibits the tyrosine phosphorylation of HER2 (p-HER2) in human breast cancer cell lines. However, there is an obvious discrepancy related to the inhibitory effects of G129R on p-HER2 between the monolayer cell culture system and in vivo. In this dissertation, I investigated the potential mechanisms by which tumor stroma exert upon the cross talk between PRLR and HER2/Neu. To compare drug response to G129R between tumors and primary cultured cells, mammary tumors were resected and cultured as small tumor chunks (≈3 mm3) or were cultured in monolayer. G129R reduced p-Neu in a dose-dependent manner (IC50 ≈10 µg/ml) in tumor chunks, but had no significant effect upon primary tumor epithelial cells grown in monolayer. Similar to that observed in mouse tumor chunks, direct co-culture of mouse tumor epithelial cells with CAFs restored the response of epithelial cells to G129R. The addition of PRL, as expected, induced p-Neu in both the tumor chunk and co-culture iiimodels. The inhibitory effect of G129R was absent when CAFs were physically separated from mouse tumor epithelial cells using a transwell system, or when CAFs were replaced with normal fibroblasts in direct co-culture with human or mouse tumor epithelial cells. In human breast cancer cell lines, the activation of HER2 was reduced by G129R when co-cultured with mouse or human CAFs. Furthermore, 3D culture of just mouse or human tumor epithelial cells with ECM components restored the same response to both G129R and PRL, suggesting that ECM components or 3D cell structure at least partially contributes to the cross talk between HER2/Neu and PRLR in breast cancer. Finally, G129R was tested in ex vivo and in vivo models. I demonstrated that G129R had an additive inhibitory effect on p-Neu in tumor chunks when combined with lapatinib, a HER1 and HER2/Neu tyrosine kinase inhibitor. Also, it reduced tyrosine phosphorylation of Neu (p-Neu) in primary mammary tumors of mice in a time- and dose-dependent manner. In conclusion, tumor stroma play a critical role in modulating the cross talk between PRLR and HER2/Neu in both human and mouse models of breast cancer. The inhibitory effects of G129R on p-HER2/Neu are dependent, at least in part, upon interactions of tumor epithelium with stroma
シェアド・リーダーシップの次元、前提と応用に関する実証研究
付記する学位プログラム名: 京都大学大学院思修館京都大学新制・課程博士博士(総合学術)甲第23590号総総博第22号新制||総総||4(附属図書館)京都大学大学院総合生存学館総合生存学専攻(主査)准教授 趙 亮, 教授 積山 薫, 准教授 関山 健学位規則第4条第1項該当Doctor of PhilosophyKyoto UniversityDGA
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