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991.
Meng Luo Xia Liu Yuangang Zu Yujie Fu Su Zhang Liping Yao Thomas Efferth 《Chemico-biological interactions》2010,188(1):151-160
Cajanol (5-hydroxy-3-(4-hydroxy-2-methoxyphenyl)-7-methoxychroman-4-one) is an isoflavanone from Pigeonpea [Cajanus cajan (L.) Millsp.] roots. As the most effective phytoalexin in pigeonpea, the cytotoxic activity of cajanol towards cancer cells has not been report as yet. In the present study, the anticancer activity of cajanol towards MCF-7 human breast cancer cells was investigated. In order to explore the underlying mechanism of cell growth inhibition of cajanol, cell cycle distribution, DNA fragmentation assay and morphological assessment of nuclear change, ROS generation, mitochondrial membrane potential (ΔΨm) disruption, and expression of caspase-3 and caspase-9, Bax, Bcl-2, PARP and cytochrome c were measured in MCF-7 cells. Cajanol inhibited the growth of MCF-7 cells in a time and dose-dependent manner. The IC50 value was 54.05 μM after 72 h treatment, 58.32 μM after 48 h; and 83.42 μM after 24 h. Cajanol arrested the cell cycle in the G2/M phase and induced apoptosis via a ROS-mediated mitochondria-dependent pathway. Western blot analysis showed that cajanol inhibited Bcl-2 expression and induced Bax expression to desintegrate the outer mitochondrial membrane and causing cytochrome c release. Mitochondrial cytochrome c release was associated with the activation of caspase-9 and caspase-3 cascade, and active-caspase-3 was involved in PARP cleavage. All of these signal transduction pathways are involved in initiating apoptosis. To the best of our knowledge, this is the first report demonstrating the cytotoxic activity of cajanol towards cancer cells in vitro. 相似文献
992.
Song X Wang X Zhuo W Shi H Feng D Sun Y Liang Y Fu Y Zhou D Luo Y 《The Journal of biological chemistry》2010,285(51):40039-40049
Heat shock protein 90α (Hsp90α) is a ubiquitously expressed molecular chaperone that is essential for eukaryotic homeostasis. Hsp90α can also be secreted extracellularly, where it has been shown to be involved in tumor metastasis. Extracellular Hsp90α interacts with and promotes the proteolytic activity of matrix metalloproteinase-2 (MMP-2). However, the regulatory mechanism of Hsp90α on MMP-2 activity is still unknown. Here we show that Hsp90α stabilizes MMP-2 and protects it from degradation in tumor cells. Further investigation reveals that this stabilization effect is isoform-specific, ATP-independent, and mediated by the interaction between the Hsp90α middle domain and the MMP-2 C-terminal hemopexin domain. Moreover, this mechanism also applies to endothelial cells that secrete more Hsp90α in their proliferating status. Furthermore, endothelial cell transmigration, Matrigel plug, and tumor angiogenesis assays demonstrate that extracellular Hsp90α promotes angiogenesis in an MMP-2-dependent manner. In sum, this study provides new insights into the molecular mechanism of how Hsp90α regulates its extracellular client proteins and also reveals for the first time the function of extracellular Hsp90α in promoting tumor angiogenesis. 相似文献
993.
SCAR Makers and Multiplex PCR-Based Rapid Molecular Typing of Lentinula edodes Strains 总被引:1,自引:0,他引:1
Xueqian Wu Haibo Li Weiwei Zhao Lizhong Fu Huazheng Peng Liang He Junwen Cheng Hailong Wei Qingqi Wu 《Current microbiology》2010,61(5):381-389
Lentinula edodes is the second most important cultivated mushroom worldwide, the most commercial strains have been identified only through
traditional phenotypic analysis. In this study, a simple rapid PCR-based molecular method was developed for distinguishing
commercial strains of L. edodes by developing specific sequence characterized amplified region (SCAR) markers and establishing multiplex PCR assays with
the SCAR primers. Derived from the randomly amplified polymorphic DNA (RAPD) and sequence-related amplified polymorphism (SRAP)
techniques, 10 informative SCAR markers were generated from 10 polymorphic RAPD and SRAP bands. The differences in SCAR phenotypes
among different strains made these SCAR markers potentially useful to characterize 6 strains and identify them from other
studied strains. Moreover, different SCAR phenotypes also made the other 17 studied strains to be divided into four distinguishable
groups. The multiplex PCR assays were further established for the joint use of some SCAR markers efficiently. Compared with
some identification methods reported previously, the special feature of this new molecular method is technically rapid and
convenient in the practical use and suitable for analyzing large numbers of samples. Thus, the simple rapid PCR-based molecular
method can be used as a helpful assistant tool for the lentinula industry. To our knowledge, this study is the first to describe
a development of a new SCAR maker-based multiplex PCR assay for rapid molecular typing of edible mushroom. 相似文献
994.
Paraoxonase-1 (PON1, EC 3.1.8.1) is a high-density lipoprotein (HDL)-associated antioxidant enzyme, and its activity correlates negatively with the level of plasma low-density lipoprotein cholesterol (LDL-C) and triglyceridemia (TG). In this study, we examined the therapeutic effect of plasmid DNA containing the human PON1 gene (pcDNA/PON1) in hyperlipidemic model rats. The rats were fed a high-fat and high-cholesterol diet for 25 days to produce a hyperlipidemic animal model. Single intravenous injection of pcDNA/PON1 into model rats prevented dyslipidemia and hepatic lipid accumulation. The mechanisms of pcDNA/PON1 in treating hyperlipidemia were associated with increases of serum antioxidant PON1 and SOD activities, and with reduction of the levels of total cholesterol (TC), LDL-C and TG. The results suggest the potential therapeutic effect of pcDNA/PON1 on hyperlipidemia. 相似文献
995.
A series of flexible multidentate ligands containing N,P-donor, 2-[N-(diphenylphosphino)methyl]amino-pyridine (L1), 2-[N-bi-(diphenylphosphino) methyl]amino-pyridine (L2), 2-[N-(diphenylphosphino)methyl]amino-7-methyl-1,8-naphthyridine (L3) and 4-[(N-diphenylphosphino)methyl]amino-pyridine) (L4) have been synthesized. The mono- and dinuclear cyclometalated platinum(II) complexes [Pt(C^N^N)L1]ClO4 (HC^N^N = 6-phenyl-2,2′-bipyridine), [Pt2(C^N^N)2L1](ClO4)2, [Pt2(C^N^N)2L2](ClO4)2, [Pt(C^N^N)L3]ClO4 and [Pt2(C^N^N)2L4](ClO4)2 were prepared and their structures determined by X-ray crystal analysis. These complexes exhibit long-lived bright orange emissions ranging from 560 to 610 nm in the solid state at room temperature. In solution, dinuclear complexes have emissions with higher quantum yields than mononuclear complexes. This can be attributed to intramolecular interaction of free functional group with Pt(II) at axial position, resulting in the quenching of phosphorescence for platinum(II) complexes in the 3MLCT excited state. 相似文献
996.
997.
Xiang‐Shu Xian Hyeyeon Park Yu Kyung Cho In Seok Lee Sang Woo Kim Myung‐Gyu Choi In‐Sik Chung Ki‐Hwan Han Jae Myung Park 《Journal of cellular biochemistry》2010,110(2):321-332
Although cannabinoids are associated with antineoplastic activity in a number of cancer cell types, the effect in gastric cancer cells has not been clarified. In the present study, we investigated the effects of a cannabinoid agonist on gastric cancer cell proliferation and invasion. The cannabinoid agonist WIN 55,212‐2 inhibited the proliferation of human gastric cancer cells in a dose‐dependent manner and that this effect was mediated partially by the CB1 receptor. We also found that WIN 55,212‐2 induced apoptosis and down‐regulation of the phospho‐AKT expression in human gastric cancer cells. Furthermore, WIN 55,212‐2 treatment inhibited the invasion of gastric cancer cells, and down‐regulated the expression of MMP‐2 and VEGF‐A through the cannabinoid receptors. Our results open the possibilities in using cannabinoids as a new gastric cancer therapy. J. Cell. Biochem. 110: 321–332, 2010. © 2010 Wiley‐Liss, Inc. 相似文献
998.
Chih‐Yu Chang Lijian Zuo Hin‐Lap Yip Chang‐Zhi Li Yongxi Li Chain‐Shu Hsu Yen‐Ju Cheng Hongzheng Chen Alex K‐Y. Jen 《Liver Transplantation》2014,4(7)
Highly efficient tandem and semitransparent (ST) polymer solar cells utilizing the same donor polymer blended with [6,6]‐phenyl‐C61‐butyric acid methyl ester (PC61BM) and [6,6]‐phenyl‐C71‐butyric acid methyl ester (PC71BM) as active layers are demonstrated. A high power conversion efficiency (PCE) of 8.5% and a record high open‐circuit voltage of 1.71 V are achieved for a tandem cell based on a medium bandgap polymer poly(indacenodithiophene‐co‐phananthrene‐quinoxaline) (PIDT‐phanQ). In addition, this approach can also be applied to a low bandgap polymer poly[2,6‐(4,4‐bis(2‐ethylhexyl)‐4H‐cyclopenta[2,1‐b;3,4‐b′]dithiophene)‐alt‐4,7‐(5‐fluoro‐2,1,3‐benzothia‐diazole)] (PCPDTFBT), and PCEs up to 7.9% are achieved. Due to the very thin total active layer thickness, a highly efficient ST tandem cell based on PIDT‐phanQ exhibits a high PCE of 7.4%, which is the highest value reported to date for a ST solar cell. The ST device also possesses a desirable average visible transmittance (≈40%) and an excellent color rendering index (≈100), permitting its use in power‐generating window applications. 相似文献
999.
Dong Chen Zhao Yang Han Xia Jun-Fu Huang Yang Zhang Tian-Nun Jiang Gui-Yu Wang Zheng-Ran Chuai Wei-Ling Fu Qing Huang 《PloS one》2014,9(4)
Genotyping of thiopurine S-methyltransferase (TPMT) is recommended for predicting the adverse drug response of thiopurines. In the current study, a novel version of allele-specific PCR (AS-PCR), termed competitive real-time fluorescent AS-PCR (CRAS-PCR) was developed to analyze the TPMT*2 genotype in ethnic Chinese. This technique simultaneously uses wild-type and mutant allele-specific scorpion primers in a single reaction. To determine the optimal conditions for both traditional AS-PCR and CRAS-PCR, we used the Taguchi method, an engineering optimization process that balances the concentrations of all components using an orthogonal array rather than a factorial array. Instead of running up to 264 experiments with the conventional factorial method, the Taguchi method achieved the same optimization using only 16 experiments. The optimized CRAS-PCR system completely avoided non-specific amplification occurring in traditional AS-PCR and could be performed at much more relaxed reaction conditions at 1% sensitivity, similar to traditional AS-PCR. TPMT*2 genotyping of 240 clinical samples was consistent with published data. In conclusion, CRAS-PCR is a novel and robust genotyping method, and the Taguchi method is an effective tool for the optimization of molecular analysis techniques. 相似文献
1000.
Xiaoyan Wu Hui Cai Asha Kallianpur Yu-Tang Gao Gong Yang Wong-Ho Chow Hong-Lan Li Wei Zheng Xiao-Ou Shu 《PloS one》2014,9(8)