3,539 research outputs found
Spin-orbit-coupling-induced magnetic heterostructure in the bilayer Bose-Hubbard system
We investigate magnetic phase in the bilayer system of ultra-cold bosons in
an optical lattice, which is involved with Raman-induced spin-orbit (SO)
coupling and laser-assisted interlayer tunneling. It is shown that there exit a
rich of spin textures such as hetero ferromagnet, heterochiral magnet, chiral
magnet with interlayer antiferromagnet. In particular, heterochiral magnet
induced by SO coupling occurs extremely rarely in real solid-state materials.
We present detailed experimental setup of realizing such a model in cold atom
system.Comment: 7 pages of RevTex4-1, 4 figure
GPER-induced signaling is essential for the survival of breast cancer stem cells.
G protein-coupled estrogen receptor-1 (GPER), a member of the G protein-coupled receptor (GPCR) superfamily, mediates estrogen-induced proliferation of normal and malignant breast epithelial cells. However, its role in breast cancer stem cells (BCSCs) remains unclear. Here we showed greater expression of GPER in BCSCs than non-BCSCs of three patient-derived xenografts of ER- /PR+ breast cancers. GPER silencing reduced stemness features of BCSCs as reflected by reduced mammosphere forming capacity in vitro, and tumor growth in vivo with decreased BCSC populations. Comparative phosphoproteomics revealed greater GPER-mediated PKA/BAD signaling in BCSCs. Activation of GPER by its ligands, including tamoxifen (TMX), induced phosphorylation of PKA and BAD-Ser118 to sustain BCSC characteristics. Transfection with a dominant-negative mutant BAD (Ser118Ala) led to reduced cell survival. Taken together, GPER and its downstream signaling play a key role in maintaining the stemness of BCSCs, suggesting that GPER is a potential therapeutic target for eradicating BCSCs
Proteomic analysis of rhein-induced cyt: ER stress mediates cell death in breast cancer cells
Rhein is a natural product purified from herbal plants such as Rheum palmatum, which has been shown to have anti-angiogenesis and anti-tumor metastasis properties. However, the biological effects of rhein on the behavior of breast cancers are not completely elucidated. To evaluate whether rhein might be useful in the treatment of breast cancer and its cytotoxic mechanism, we analyzed the impact of rhein treatment on differential protein expression as well as redox regulation in a non-invasive breast cancer cell line, MCF-7, and an invasive breast cancer cell line, MDA-MB-231, using lysine- and cysteine-labeling two-dimensional difference gel electrophoresis (2D-DIGE) combined with MALDI-TOF/TOF mass spectrometry. This proteomic study revealed that 73 proteins were significantly changed in protein expression; while 9 proteins were significantly altered in thiol reactivity in both MCF-7 and MDA-MB-231 cells. The results also demonstrated that rhein-induced cytotoxicity in breast cancer cells mostly involves dysregulation of cytoskeleton regulation, protein folding, the glycolysis pathway and transcription control. A further study also indicated that rhein promotes misfolding of cellular proteins as well as unbalancing of the cellular redox status leading to ER-stress. Our work shows that the current proteomic strategy offers a high-through-put platform to study the molecular mechanisms of rhein-induced cytotoxicity in breast cancer cells. The identified differentially expressed proteins might be further evaluated as potential targets in breast cancer therapy
Fucosyltransferase 1 and 2 play pivotal roles in breast cancer cells.
FUT1 and FUT2 encode alpha 1, 2-fucosyltransferases which catalyze the addition of alpha 1, 2-linked fucose to glycans. Glycan products of FUT1 and FUT2, such as Globo H and Lewis Y, are highly expressed on malignant tissues, including breast cancer. Herein, we investigated the roles of FUT1 and FUT2 in breast cancer. Silencing of FUT1 or FUT2 by shRNAs inhibited cell proliferation in vitro and tumorigenicity in mice. This was associated with diminished properties of cancer stem cell (CSC), including mammosphere formation and CSC marker both in vitro and in xenografts. Silencing of FUT2, but not FUT1, significantly changed the cuboidal morphology to dense clusters of small and round cells with reduced adhesion to polystyrene and extracellular matrix, including laminin, fibronectin and collagen. Silencing of FUT1 or FUT2 suppressed cell migration in wound healing assay, whereas FUT1 and FUT2 overexpression increased cell migration and invasion in vitro and metastasis of breast cancer in vivo. A decrease in mesenchymal like markers such as fibronectin, vimentin, and twist, along with increased epithelial like marker, E-cadherin, was observed upon FUT1/2 knockdown, while the opposite was noted by overexpression of FUT1 or FUT2. As expected, FUT1 or FUT2 knockdown reduced Globo H, whereas FUT1 or FUT2 overexpression showed contrary effects. Exogenous addition of Globo H-ceramide reversed the suppression of cell migration by FUT1 knockdown but not the inhibition of cell adhesion by FUT2 silencing, suggesting that at least part of the effects of FUT1/2 knockdown were mediated by Globo H. Our results imply that FUT1 and FUT2 play important roles in regulating growth, adhesion, migration and CSC properties of breast cancer, and may serve as therapeutic targets for breast cancer
On the intrinsic shape of gamma-ray spectrum for Fermi blazars
The curvature of the -ray spectrum in blazars may reflect the
intrinsic distribution of the emitting electron distribution, which will
further give some information on the possible acceleration and cooling
processes in the emitting region. The -ray spectra of Fermi blazars are
normally fitted either by a single power-law (PL) or a log-normal (call
Logarithmic Parabola, LP) form. The possible reason for this differnece is not
unclear. We statistically explore this issue based on the different
observational properties of 1419 Fermi blazars in the 3LAC Clean sample. We
find that the -ray flux (100 MeV-100 GeV) and variability index follow
bimodal distributions for PL and LP blazars, where -ray flux and
variability index show {a positive correlation}. However, the distributions of
the -ray luminosity and redshift follow a unimodal distribution. Our
results suggest that the bimodal distribution of -ray flux for LP and
PL blazars may be not intrinsic and all blazars may have an intrinsic curved
-ray spectrum and the PL spectrum is just caused by the fitting effect
due to the less photons.Comment: Accepted for publication in RAA. 9 pages, 1 figure, 2 tabl
Cultural Heritage and Its Authenticity: Spatialization of Local Pasts through Making Models in Jinguashi Mine, Taiwan
http://purl.org/coar/resource_type/c_650
- …
