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101.
Kala Jessie Jaime Jacqueline Jayapalan Kien‐Chai Ong Zubaidah Haji Abdul Rahim Rosnah Mohd Zain Kum‐Thong Wong Onn Haji Hashim 《Electrophoresis》2013,34(17):2495-2502
Confirmation of oral squamous cell cancer (OSCC) currently relies on histological analysis, which does not provide clear indication of cancer development from precancerous lesions. In the present study, whole saliva proteins of patients with OSCC (n = 12) and healthy subjects (n = 12) were separated by 2DE to identify potential candidate biomarkers that are much needed to improve detection of the cancer. The OSCC patients’ 2DE saliva protein profiles appeared unique and different from those obtained from the healthy subjects. The patients’ saliva α1‐antitrypsin (AAT) and haptoglobin (HAP) β chains were resolved into polypeptide spots with increased microheterogeneity, although these were not apparent in their sera. Their 2DE protein profiles also showed presence of hemopexin and α‐1B glycoprotein, which were not detected in the profiles of the control saliva. When subjected to densitometry analysis, significant altered levels of AAT, complement C3, transferrin, transthyretin, and β chains of fibrinogen and HAP were detected. The increased levels of saliva AAT, HAP, complement C3, hemopexin, and transthyretin in the OSCC patients were validated by ELISA. The strong association of AAT and HAP with OSCC was further supported by immunohistochemical staining of cancer tissues. The differently expressed saliva proteins may be useful complementary biomarkers for the early detection and/or monitoring of OSCC, although this requires validation in clinically representative populations. 相似文献
102.
Synthesis of (E)‐5‐Methoxy‐2‐styryl‐4‐pyrones as Potent Growth‐Inhibitory Agents Against Hepatocellular Carcinoma Cells 下载免费PDF全文
Yu‐Hua Chen Pei‐Jung Lu Christopher Hulme Arthur Y. Shaw 《Journal of heterocyclic chemistry》2014,51(1):56-61
The present study a series of (E)‐5‐methoxy‐2‐styryl‐4H‐pyran‐4‐ones 6a , 6b , 6c , 6d , 6e , 6f , 6g , 6h , 6i , 6j was synthesized and evaluated for growth inhibitory inhibition against carcinoma cells. The growth inhibition study of eight carcinoma cell lines was examined and demonstrated that SKHep cells exhibit significant structure‐activity relationship in response to the tested compounds. Among them, 6f showed the most potent activity against SKHep, A549, AGS, and H460 cell lines with GI50 values of 0.17, 8.3, 3.6, 8.0 μM, respectively. 相似文献
103.
Xinna Wang Xinshu XiaAlbert Wingnang Leung Junyan XiangYuan Jiang Ping WangJing Xu Heping YuDingqun Bai Chuanshan Xu 《Ultrasonics》2011,51(2):165-170
Objectives
Curcumin, a natural pigment from the traditional Chinese herb, has shown promise as an efficient enhancer of ultrasound. The present study aims to investigate ultrasound-induced cellular destruction of nasopharyngeal carcinoma cells in the presence of curcumin in vitro.Methods
Nasopharyngeal carcinoma cell line CNE2 cells were incubated by 10 μm curcumin and then were treated by ultrasound for 8 s at the intensity of 0.46 W/cm2. Cytotoxicity was evaluated using MTT assay and light microscopy. Mitochondrial damage was analyzed using a confocal laser scanning microcopy with Rhodamine 123 and ultrastructural changes were observed using a transmission electron microscopy (TEM).Results
MTT assay showed that cytotoxicity induced by ultrasound treatment alone and curcumin treatment alone was 18.16 ± 2.37% and 24.93 ± 8.30%, respectively. The cytotoxicity induced by the combined treatment of ultrasound and curcumin significantly increased up to 86.67 ± 7.78%. TEM showed that microvillin disappearance, membrane blebbing, chromatin condensation, swollen mitochondria, and mitochondrial myelin-like body were observed in the cells treated by ultrasound and curcumin together. The significant collapse of mitochondrial membrane potential (MMP) was markedly observed in the CNE2 cells after the combined treatment of curcumin and ultrasound.Conclusions
Our findings demonstrated that ultrasound sonication in the presence of curcumin significantly killed the CNE2 cells and induced ultrastructural damage and the dysfunction of mitochondria, suggesting that ultrasound treatment remarkably induced cellular destruction of nasopharyngeal carcinoma cells in the presence of curcumin. 相似文献104.
Jing Han Siwang Zhang Junxin Niu Chunli Zhang Weichen Dai Yuanyuan Wu Lihong Hu 《Molecules (Basel, Switzerland)》2020,25(23)
Background: Microtubule-targeted drugs are the most effective drugs for adult patients with certain solid tumors. Taccalonolide AJ (AJ) can stabilize tubulin polymerization by covalently binding to β-tubulin, which enables it to play a role in the treatment of tumors. However, its clinical applications are largely limited by low water solubility, chemical instability in water, and a narrow therapeutic window. Clear-cell renal-cell carcinoma (cc RCC) accounts for approximately 70% of RCC cases and is prone to resistance to particularly targeted therapy drugs. Methods: we prepared a water-soluble cyclodextrin-based carrier to serve as an effective treatment for cc RCC. Results: Compared with AJ, taccalonolide AJ-hydroxypropyl-β-cyclodextrin (AJ-HP-β-CD) exhibited superior selectivity and activity toward the cc RCC cell line 786-O vs. normal kidney cells by inducing apoptosis and cell cycle arrest and inhibiting migration and invasion of tumor cells in vitro. According to acute toxicity testing, the maximum tolerated dose (MTD) of AJ-HP-β-CD was 10.71 mg/kg, which was 20 times greater than that of AJ. Assessment of weight changes showed that mouse body weight recovered over 7–8 days, and the toxicity could be greatly reduced by adjusting the injections from once every three days to once per week. In addition, we inoculated 786-O cells to generate xenografted mice to evaluate the anti-tumor activity of AJ-HP-β-CD in vivo and found that AJ-HP-β-CD had a better tumor inhibitory effect than that of docetaxel and sunitinib in terms of tumor growth and endpoint tumor weight. These results indicated that cyclodextrin inclusion greatly increased the anti-tumor therapeutic window of AJ. Conclusions: the AJ-HP-β-CD complex developed in this study may prove to be a novel tubulin stabilizer for the treatment of cc RCC. In addition, this drug delivery system may broaden the horizon in the translational study of other chemotherapeutic drugs. 相似文献
105.
Haidong Xu Chungyoul Choe Seung-Hun Shin Sung-Won Park Ho-Shik Kim Seung-Hyun Jung Seon-Hee Yim Tae-Min Kim Yeun-Jun Chung 《Experimental & molecular medicine》2014,46(5):e97
Although it has been suggested that kinesin family member 14 (KIF14) has oncogenic potential in various cancers, including hepatocellular carcinoma (HCC), the molecular mechanism of this potential remains unknown. We aimed to elucidate the role of KIF14 in hepatocarcinogenesis by knocking down KIF14 in HCC cells that overexpressed KIF14. After KIF14 knockdown, changes in tumor cell growth, cell cycle and cytokinesis were examined. We also examined cell cycle regulatory molecules and upstream Skp1/Cul1/F-box (SCF) complex molecules. Knockdown of KIF14 resulted in suppression of cell proliferation and failure of cytokinesis, whereas KIF14 overexpression increased cell proliferation. In KIF14-silenced cells, the levels of cyclins E1, D1 and B1 were profoundly decreased compared with control cells. Of the cyclin-dependent kinase inhibitors, the p27Kip1 protein level specifically increased after KIF14 knockdown. The increase in p27Kip1 was not due to elevation of its mRNA level, but was due to inhibition of the proteasome-dependent degradation pathway. To explore the pathway upstream of this event, we measured the levels of SCF complex molecules, including Skp1, Skp2, Cul1, Roc1 and Cks1. The levels of Skp2 and its cofactor Cks1 decreased in the KIF14 knockdown cells where p27Kip1 accumulated. Overexpression of Skp2 in the KIF14 knockdown cells attenuated the failure of cytokinesis. On the basis of these results, we postulate that KIF14 knockdown downregulates the expression of Skp2 and Cks1, which target p27Kip1 for degradation by the 26S proteasome, leading to accumulation of p27Kip1. The downregulation of Skp2 and Cks1 also resulted in cytokinesis failure, which may inhibit tumor growth. To the best of our knowledge, this is the first report that has identified the molecular target and oncogenic effect of KIF14 in HCC. 相似文献
106.
107.
用PCR技术扩增环加氧酶2(COX-2)基因的C末端777bp的片段,插入到pET-28b(+)中,构建原核表达载体.转入大肠杆菌BL21(DE3),经IPTG诱导产生包涵体形式his-COX-2融合蛋白.用镍离子螫合柱(Ni—NTA)纯化融合蛋白,获得纯度较高的原核表达蛋白.纯化后的蛋白免疫家兔制备多克隆抗体,用ELISA及Western blotting分别检测抗体.用此抗体Western blotting检测肝癌组织中的环加氧酶2的表达.ELISA及Western blotting结果显示免疫家兔所得的环加氧酶2抗体具有很高的效价,并能够特异性的识别真核细胞中的环加氧酶2.用此抗体检测肝癌组织中的环加氧酶2的表达.证实肝癌组织中伴随有环加氧酶2的大量表达.同时所得的环加氧酶2抗体具有很高的效价和特异性,为进一步研究环加氧酶2的功能提供了条件。 相似文献
108.
Drug Delivery: Biodegradable Passion Fruit‐Like Nano‐Architectures as Carriers for Cisplatin Prodrug (Part. Part. Syst. Charact. 11/2016) 下载免费PDF全文
109.
Haixing Wang Ting Li Qing Shen Zhifang Liu You-Wei Chen Darong Huang Jiancheng Yu Long Wang 《Electrophoresis》2023,44(13-14):1057-1067
Liver cancer is generally considered the leading cause of cancer deaths worldwide, and hepatocellular carcinoma (HCC) contributes to more than 90% of liver cancers. The altered lipid metabolism for rapid cancer cell growth and tumor formation has been frequently proven. In this study, an ambient ionization mass spectrometry technique, rapid evaporative ionization mass spectrometry (REIMS) using a monopolar electric knife, called iKnife, was systematically optimized and employed for ex vivo analysis of 12 human HCC tumor tissue specimens together with the paired paracancerous tissue (PT) and noncancerous liver tissue (NCT) specimens. Nine free fatty acids and 34 phospholipids were tentatively identified according to their extract masses and/or tandem mass spectra. With the help of statistical methods, 7 free fatty acids and 10 phospholipids were distributed differently in 3 types of liver tissue specimens (95% confidence interval). The box plots showed these characterized lipid metabolites varied in PT, HCC, and NCT. Compared with PT and NCT, the upregulations of four common fatty acids FA 18:0, FA 20:4, FA 16:0, and FA 18:1, together with phospholipids PC 36:1, PE 38:3, PE (18:0/20:4), PA (O-36:1), PC (32:1), PC 32:0, PE 34:0, and PC (16:0/18:1), were found in HCC specimens. The sensitivity and specificity of the established statistic model for real-time HCC tumor diagnosis were 100% and 90.5%, respectively. This study demonstrated that the described REIMS technique is a potential method for rapid lipidomic analysis and characterization of HCC tumor tissue. 相似文献
110.
We used Raman micro-spectroscopy technique to analyze the molecular changes associated with oral squamous cell carcinoma (SCC) cells in the form of frozen tissue. Previously, Raman micro-spectroscopy technique on human tissue was mainly based on spectral analysis, but we worked on imaging of molecular structure. In this study, we evaluated the distribution of four components at the cell level (about 10 μm) to describe the changes in protein and molecular structures of protein belonging to malignant tissue. We analyzed ten oral SCC samples of five patients without special pretreatments of the use of formaldehyde. We obtained cell level images of the oral SCC cells at various components (peak at 935 cm−1: proline and valine, 1004 cm−1: phenylalanine, 1223 cm−1: nucleic acids, and 1650 cm−1: amide I). These mapping images of SCC cells showed the distribution of nucleic acids in the nuclear areas; meanwhile, proline and valine, phenylalanine, and amide I were detected in the cytoplasm areas of the SCC cells. Furthermore, the peak of amide I in the cancer area shifts to the higher wavenumber side, which indicates the α-helix component may decrease in its relative amounts of protein in the β-sheet or random coil conformation. Imaging of SCC cells with Raman micro-spectroscopy technique indicated that such a new observation of cancer cells is useful for analyzing the detailed distribution of various molecular conformation within SCC cells. 相似文献