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21.
The Dendrobrium species have been commonly used in traditional Chinese medicine as a tonic to nourish the stomach, replenish body fluid, and reduce fever. However, their application as possible therapeutic agents for the treatment of cancers has not been examined. In this study, we want to examine the efficacy of using moscatilin, a natural antiplatelet agent extracted from the stems of Dendrobrium loddigesii, as an anticancer agent. Our results have shown that moscatilin exerts potent cytotoxic effect against cancer cell lines derived from different tissue origins, including those from the placenta, stomach, and lung, but not those from the liver. In addition, we have found that the mechanism of action of moscatilin may be related to its ability to induce a G2 phase arrest in responsive cells. However, unlike some G2 arresting agents, moscatilin has no detectable inhibitory effect on cyclin B-cdc-2 kinase activity. Thus, the precise nature of its cytotoxic mechanism remains to be determined. Our results in this study imply that moscatilin is potentially efficacious for chemoprevention and/or chemotherapy against some types of cancer.  相似文献   
22.
A survey on the role played by ceramide within the sphingolmyelin pathway is here reported, taking into account its importance as an intracellular effector molecule in apoptosis. Recently, several analogs of ceramide, able to pass the cell membrane and then to induce apoptosis, have been developed as a new potential approach in anticancer therapy.  相似文献   
23.
Purpose: 10-Hydroxycamptothecin (HCPT) is an indole alkaloid isolated from a Chinese tree, Camptotheca acuminata, and has a wide spectrum of anticancer activity in vitro and in vivo mainly through inhibitory effects on topoisomerase I. HCPT has been shown to be more potent and less toxic than camptothecin and has recently undergone clinical trials. To determine how HCPT might be best used as an anticancer agent, preclinical studies of the pharmacokinetics, tissue distribution, metabolism and elimination of HCPT in rats were undertaken. Methods: HCPT was administered to rats by i.v. bolus injection at doses of 1, 3, and 10 mg/kg body weight. HCPT (lactone and carboxylate) and its metabolites in plasma, urine, feces, and various tissues were quantitated by reversed-phase HPLC. Pharmacokinetic parameters were then estimated. Results: Following i.v. administration at doses of 3 or 10 mg/kg, the plasma concentration-time profile for lactone HCPT could be best described by a three-compartment model, with terminal elimination half-lives of 140.4 and 428.6 min, respectively. A two-compartment model was used to fit the plasma concentration-time curve at 1 mg/kg, with a terminal elimination half-life of 30.5 min. Carboxylate HCPT had a longer half-life than the lactone form of HCPT. During the initial 6 h after dosing, urinary excretion was the major route of elimination, and fecal excretion became the major route of elimination thereafter. HCPT was widely distributed to various tissues including the enterohepatic system, kidney, and bone marrow. The lactone form of HCPT was detectable in various tissues examined up to 72 h after dosing at all the three test doses. HCPT glucuronides were present in plasma, urine, feces and various tissues. No significant toxicity was observed at doses of 1 or 3 mg/kg. Polyuria and hematuria were observed only during the initial 3 h after dosing at 10 mg/kg. Conclusions: Prolonged elimination of HCPT in vivo may have a significant impact on its therapeutic effects. HCPT is metabolized to its carboxylate form and glucuronides. Dose-dependent toxicity was observed with i.v. administration of HCPT. The results of this study should be useful in the design of future human trials with this anticancer drug. Received: 6 September 1996 / Accepted: 15 July 1997  相似文献   
24.
Vitex negundo L. (V. negundo) is one of the important medicinal and anticancer enhancer herbs. This plant is commonly used in the preparation of traditional drugs to treat numerous diseases. Inspired by the medicinal properties of this plant, the current study aimed to investigate antiproliferative potential and the primary molecular mechanisms of the apoptotic induction against human HepG2 and MCF-7 cell lines, by pure compounds isolated from targeted fractions of V. negundo which were characterized by NMR, FTIR and HRMS analysis and identified as artemetin (FLV1), vitexicarpin (FLV2), and penduletin (FLV3) compounds. The FLV1, FLV2, and FLV3 compounds were evaluated for the antiproliferative potential against HepG2 and MCF-7 cell lines by cell viability assay and exhibited IC50 values of 2.3, 23.9 and 5.6 µM and 3.9, 25.8, and 6.4 µM, respectively. In addition, those compounds increased the level of reactive oxygen species production, induced cell death occurred via apoptosis, demonstrated by Annexin V-staining cells, contributed significantly to DNA damage, and led to the activation of caspase3/caspase8 pathways.Additionally, molecular docking was also conducted to rationalize the cancer cells inhibitory and to evaluate the ability of the FLV1, FLV2, and FLV3 compounds to be developed as good drug candidates for cancers treatment.  相似文献   
25.
目的 寻找具有新型骨架结构的成纤维细胞生长因子受体(FGFR)抑制剂.方法 基于活性化合物1和2的结构,利用“杂交”设计原理,设计并合成了一系列3-苯并咪唑-6-(3,5-二甲氧基苯基)吲唑类衍生物.结果 目标化合物经1 HNMR和质谱确证结构,并评价了其对人胃癌细胞SNU-16的增殖抑制活性.结论 该系列化合物均对FGFR高表达的肿瘤细胞有较好的增殖抑制活性,其中,化合物3g的IC50值达到0.32 μmol·L-1.3-苯并咪唑-6-(3,5-二甲氧基苯基)吲唑是一类新型的FGFR抑制剂骨架,值得进一步结构修饰研究.  相似文献   
26.
吉非替尼为靶向性表皮生长因子受体(EGFR)酪氨酸激酶抑制剂,2005年批准进口中国用于治疗局部晚期及或转移性非小细胞肺癌(NSCLC),其疗效好且血液系统不良反应较少,最常见的不良反应为腹泻和皮肤反应.2015年7月13日,美国食品药品监督管理局批准吉非替尼用于转移性非小细胞肺癌靶向性表皮生长因子受体基因突变的患者.本文主要综述了其近年国内外的临床研究进展.  相似文献   
27.
A new series of N-substituted imide derivatives have been synthesized by treating phthalic anhydride, naphthalic anhydride and their substituted derivatives with 2-hydrazino-1-imidazoline hydrobromide, various para-substituted aryl amines, aminoglutethimide and 2,4-dinitrophenyl hydrazine. Compounds 9, 10, 12, 18, 19, 23, 24 and 34-36 have been selected and screened for antineoplastic activity by National Cancer Institute, Bethesda, USA. Some newer aminoglutethimide derivatives 37-39 have also been prepared in order to study the effect of N-substitution on its pharmacological profile for the treatment of carcinoma. These compounds (37-39) have exhibited weak inhibition of human placental aromatase as compared to aminoglutethimide.  相似文献   
28.
Herein, we report reactive oxygen species (ROS)- and pH-responsive biodegradable polyethylene glycol (PEG)-block-polycarbonate by installing thioether groups onto the polycarbonate and its self-assembled core/shell structured micelles for anticancer drug delivery. Oxidation of thioethers to sulfoxide and subsequently sulfone induces an increase in hydrophilicity, resulting in more hydrophilic micellar core. This phase-change caused the micelles to swell and enhance cargo release. Carboxylic acid groups have also been installed onto thioether-containing polycarbonate to promote loading of amine-containing anticancer doxorubicin through electrostatic interaction. Urea-functionalized thioether-containing PEG-block-polycarbonates were synthesized to mix with the acid-functionalized PEG-block-polycarbonate for stabilizing micelle structure through hydrogen-bonding interaction. The mixed micelles were 50?nm in diameter and had a 25?wt% loading capacity for doxorubicin. Enhanced drug release from the micelles was triggered by low pH and high content of ROS. Drug-encapsulated micelles accumulated in tumors through leaky tumor vasculature in PC-3 human prostate cancer xenograft mouse model.  相似文献   
29.
30.
Conjugation of cholesterol moiety to active compounds for either cancer treatment or diagnosis is an attractive approach. Cholesterol derivatives are widely studied as cancer diagnostic agents and as anticancer derivatives either in vitro or in vivo using animal models. In largely growing studies, anticancer agents have been chemically conjugated to cholesterol molecules, to enhance their pharmacokinetic behavior, cellular uptake, target specificity, and safety. To efficiently deliver anticancer agents to the target cells and tissues, many different cholesterol–anticancer conjugates were synthesized and characterized, and their anticancer efficiencies were tested in vitro and in vivo.  相似文献   
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