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991.
Wan Mu Xuefang Cheng Xue Zhang Ying Liu Qianzhou Lv Gaolin Liu Jigang Zhang Xiaoyu Li 《Journal of cellular and molecular medicine》2020,24(14):8151-8165
Hepatocellular carcinoma (HCC) is the sixth most common malignancy with limited treatment options. Hinokiflavone (HF), a natural biflavonoid, has shown to inhibit the proliferation of melanoma, whereas its antitumour effect against HCC and the underlying mechanisms remain elusive. Here, we aimed at evaluating its antitumour effect against HCC in both in vitro and in vivo. Cell counting kit 8, colony formation assay, PI/RNase staining and Western blotting revealed that HF inhibited the proliferation of HCC cells via G0/G1 cell cycle arrest with p21/p53 up‐regulation. DAPI staining, Annexin V‐FITC/PI staining and Western blotting confirmed that HF triggered caspase‐dependent apoptosis. Moreover, HF increased the levels of mitochondrial reactive oxygen species (mtROS) and activated c‐Jun N‐terminal kinase (JNK) pathway, as measured by MitoSOX Red staining and Western blotting. After respectively inhibiting mtROS (Mito‐TEMPO) and JNK (SP600125), HF‐induced apoptosis was reversed. Additionally, Western blotting documented that HF suppressed nuclear factor kappa B (NF‐κB) activity and the anti‐apoptotic genes downstream, contributing to cell apoptosis. Finally, in vivo studies demonstrated that HF significantly impaired tumour growth in HCC xenograft. Collectively, these findings suggested that HF induced apoptosis through activating mtROS/JNK/caspase pathway and inhibiting NF‐κB signalling, which may represent a novel therapeutic agent for treating HCC. 相似文献
992.
Zhenbing Lv Huichun Zou Kaiwen Peng Jianmei Wang Yi Ding Yuling Li Xiaoli Ren Feifei Wang Rui Chang Li Liang Yanqing Ding 《PloS one》2013,8(10)
Background
BTG3 (B-cell translocation gene 3) has been identified as a tumor suppressor and hypermethylation contributes to its down-regulation in some tumors, but its role in hepatocellular carcinoma (HCC) remain unknown. This study aimed to detect the expression and methylation status of BTG3 in HCC cell lines or tissues, and determine its function in HCC progression.Methodology
The expression of BTG3 was detected in HCC cell lines and HCC tissue by real-time RT-PCR, Western blot or immunohistochemistry. The promoter methylation status of BTG3 was measured by using methylation-specific PCR in HCC cell lines. A series of assays were performed to evaluate the effect of BTG3 on proliferation, invasion and cell cycle transition in vitro.Results
BTG3 expression was lower in HCC cell lines than in hepatocyte cell line LO2 (P<0.05). BTG3 was also down-regulated in HCC tissues. Its expression was positively correlated with differentiation and distant metastasis (P<0.05). Patients with lower BTG3 expression had shorter overall survival time (P=0.029). DNA methylation directed repression of BTG3 mRNA expression in HCC cell lines. BTG3 suppressed proliferation, invasion and induces G1/S cycle arrest of HCC cells in vitro.Conclusion
Down-regulation of BTG3 due to the promoter hypermethylation is closely associated with proliferation, invasion and cell cycle arrest of HCC cells. It may be a novel prognostic biomarker for HCC patients. 相似文献993.
994.
Shuangliang Lv Qiang Yu Xinshu Zhuang Zhenghong Yuan Wen Wang Qiong Wang Wei Qi Xuesong Tan 《Bioenergy Research》2013,6(4):1128-1134
Sugarcane bagasse (SCB) was pretreated with liquid hot water (LHW) and aqueous ammonia (AA), with the objective of investigating the influence of hemicellulose and lignin removal on the enzymatic digestibility and sugar recovery. The experimental results show that LHW and aqueous ammonia have a good performance in terms of hemicellulose dissolution and lignin removal respectively. The biggest xylan recovery of 74.3 % was obtained for LHW pretreatment at 160 °C, 5 %?w/v for 20 min with the xylan dissolution of 83.1 %. And the biggest lignin removal of 84.0 % was obtained for aqueous ammonia pretreatment at 160 °C, 10 %?w/v for 60 min. Moreover, the aperture and surface area of the sample were enlarged by the liquid hot water, which improves the accessibility of the substrate to the enzyme. The lignin removal caused by aqueous ammonia pretreatment can reduce the absorption of enzyme. In addition, the correlation between the compositional change and the enzymatic digestibility indicates that the removal of hemicellulose was more effective than lignin for destruction of the hemicellulose–lignin–cellulose structure. 相似文献
995.
The G-protein-coupled estrogen receptor 1 (GPER) has recently been reported to mediate the non-genomic action of estrogen in different types of cells and tissues. G-1 (1-[4-(6-bromobenzo[1,3] dioxol-5yl)-3a,4,5,9b-tetrahydro-3H-cyclopenta[c]quinolin-8-yl]-ethanone) was developed as a potent and selective agonist for GPER. G-1 has been shown to induce the expression of genes and activate pathways that facilitate cancer cell proliferation by activating GPER. Here we demonstrate that G-1 has an anticancer potential with a mechanism similar to vinca alkaloids, the commonly used chemotherapy drugs. We found that G-1 blocks tubulin polymerization and thereby interrupts microtubule assembly in ovarian cancer cells leading to the arrest of cell cycle in the prophase of mitosis and the suppression of ovarian cancer cell proliferation. G-1 treatment also induces apoptosis of ovarian cancer cells. The ability of G-1 to target microtubules to suppress ovarian cancer cell proliferation makes it a promising candidate drug for treatment of ovarian cancer. 相似文献
996.
The detection of airport attracts lots of attention and becomes a hot topic recently because of its applications and importance in military and civil aviation fields. However, the complicated background around airports brings much difficulty into the detection. This paper presents a new method for airport detection in remote sensing images. Distinct from other methods which analyze images pixel by pixel, we introduce visual attention mechanism into detection of airport and improve the efficiency of detection greatly. Firstly, Hough transform is used to judge whether an airport exists in an image. Then an improved graph-based visual saliency model is applied to compute the saliency map and extract regions of interest (ROIs). The airport target is finally detected according to the scale-invariant feature transform features which are extracted from each ROI and classified by hierarchical discriminant regression tree. Experimental results show that the proposed method is faster and more accurate than existing methods, and has lower false alarm rate and better anti-noise performance simultaneously. 相似文献
997.
998.
The volatile anesthetic, isoflurane, protects the heart from ischemia/reperfusion (I/R) injury. Aldehyde dehydrogenase 2 (ALDH2) is thought to be an endogenous mechanism against ischemia-reperfusion injury possibly through detoxification of toxic aldehydes. We investigated whether cardioprotection by isoflurane depends on activation of ALDH2.Anesthetized rats underwent 40 min of coronary artery occlusion followed by 120 min of reperfusion and were randomly assigned to the following groups: untreated controls, isoflurane preconditioning with and without an ALDH2 inhibitor, the direct activator of ALDH2 or a protein kinase C (PKCε) inhibitor. Pretreatment with isoflurane prior to ischemia reduced LDH and CK-MB levels and infarct size, while it increased phosphorylation of ALDH2, which could be blocked by the ALDH2 inhibitor, cyanamide. Isolated neonatal cardiomyocytes were treated with hypoxia followed by reoxygenation. Hypoxia/reoxygenation (H/R) increased cardiomyocyte apoptosis and injury which were attenuated by isoflurane and forced the activation of ALDH2. In contrast, the effect of isoflurane-induced protection was almost abolished by knockdown of ALDH2. Activation of ALDH2 and cardioprotection by isoflurane were substantially blocked by the PKCε inhibitor. Activation of ALDH2 by mitochondrial PKCε plays an important role in the cardioprotection of isoflurane in myocardium I/R injury. 相似文献
999.
Jiao Xu Zhongqiong Yin Li Li Anchun Cheng Renyong Jia Xu Song Hongke Lu Shujun Dai Cheng Lv Xiaoxia Liang Changliang He Ling Zhao Gang Su Gang Ye Fei Shi 《PloS one》2013,8(6)
Duck viral enteritis (DVE) is an acute, contagious herpesvirus infection of ducks, geese, and swans of all ages and species. This disease has been responsible for significant economic losses in domestic and wild waterfowl as a result of mortality, and decreased egg production. Resveratrol is a naturally occurring phytoalexin in specific plants and exhibits inhibitory activity against many kinds of virus. In this paper, resveratrol was found to inhibit duck enteritis virus (DEV) replication in a dose-dependent manner, with a 50% inhibition concentration of 3.85 μg/mL. The inhibition in virus multiplication in the presence of resveratrol was not attributed to direct inactivation or inhibition of virus attachment to the host cells, but to the inhibition of viral multiplication in host cells. The assay of the time of addition limited the drug effect during the first 8 h of infection. This conclusion was supported by the ultrastructure images of the early stage of DEV infection, which showed that the replication of virus nucleic acid and the formation of the capsid in the cell nucleus were suppressed. In the indirect immunofluorescence assay, proteins expression in DEV infected duck embryo fibroblasts (DEFs) within 24 h post-infection (p.i.) was also effectively suppressed by resveratrol. In summary, the resveratrol has a good activity against DEV infection in vitro, which could be attributed to that fact that several essential immediate early viral proteins for virus replication were impacted by resveratrol. 相似文献
1000.