Characterization of MTAP gene expression in breast cancer patients and cell lines

MTAP is a ubiquitously expressed gene important for adenine and methionine salvage. The gene is located at 9p21, a chromosome region often deleted in breast carcinomas, similar to CDKN2A, a recognized tumor suppressor gene. Several research groups have shown that MTAP acts as a tumor suppressor, and some therapeutic approaches were proposed based on a tumors\ub4 MTAP status. We analyzed MTAP and CDKN2A gene (RT-qPCR) and protein (western-blotting) expression in seven breast cancer cell lines and evaluated their promoter methylation patterns to better characterize the contribution of these genes to breast cancer. Cytotoxicity assays with inhibitors of de novo adenine synthesis (5-FU, AZA and MTX) after MTAP gene knockdown showed an increased sensitivity, mainly to 5-FU. MTAP expression was also evaluated in two groups of samples from breast cancer patients, fresh tumors and paired normal breast tissue, and from formalin-fixed paraffin embedded (FFPE) core breast cancer samples diagnosed as Luminal-A tumors and triple negative breast tumors (TNBC). The difference of MTAP expression between fresh tumors and normal tissues was not statistically significant. However, MTAP expression was significantly higher in Luminal-A breast tumors than in TNBC, suggesting the lack of expression in more aggressive breast tumors and the possibility of using the new approaches based on MTAP status in TNB

Simulations of detonation wave propagation in rectangular ducts using a three-dimensional WENO scheme

10.1016/j.combustflame.2008.06.013Combustion and Flame1544644-659CBFM

Synthesis and characterization of In<inf>2</inf>O<inf>3</inf>/SnO <inf>2</inf> hetero-junction beaded nanowires

Hetero-junction beaded nanowires were synthesized via a simple thermal vapor deposition method. These nanowires were characterized with XRD, Raman, SEM, TEM, HRTEM, SAED and PL spectroscopy. Many single-crystal In 2O3 beads epitaxially grown along the axis of the single-crystal core SnO2 nanowires form the beaded nanowires. The In2O3 beads have definite orientations along the [2 0 0] direction of the core SnO2 nanowires and show regular rhombohedral morphology. A possible growth mechanism for the beaded nanowires is proposed. © 2005 Published by Elsevier B.V

Synthesis, structure, and photoluminescence of Zn<inf>2</inf>SnO <inf>4</inf> single-crystal nanobelts and nanorings

A large quantity of single-crystal Zn2SnO4 (ZTO) nanobelts is synthesized by using a thermal evaporation method. The lengths of the nanobelts are up to several hundreds of micrometers, and the average width and thickness are about 400 and 30 nm, respectively. Some ring-like nanobelts, called nanorings here, are also observed. The nanobelts are characterized in detail with scanning electron microscope, X-ray powder diffraction, transmission electron microscope, high-resolution transmission electron microscope and selected area electron diffraction. Possible growth mechanisms for the ZTO nanobelts and nanorings are proposed. In addition, the photoluminescence spectrum (PL) of the nanobelts at room temperature shows a stable broad blue-green emission around the 400-600 nm wavelengths with a maximum center at 490 nm. The strong PL emission of the nanobelts may find potential applications in nano-scale optoelectronic devices. © 2004 Elsevier Ltd. All rights reserved