微管蛋白聚合抑制剂秋水仙碱衍生物的研究进展

微管是真核细胞骨架的重要组成部分,它由α和β微管蛋白异二聚体聚合形成,在细胞有丝分裂中具有非常重要的作用。因此,微管成为抗癌药物的重要靶点之一,微管蛋白抑制剂也成为一类有效的抗癌药物。秋水仙碱是典型的微管蛋白聚合抑制剂,但由于不良反应大,限制了其作为抗肿瘤药物在临床的应用。近年来,对秋水仙碱的结构修饰主要集中在C环的10位和B环的7位侧链,包括C环10位的甲氧基被脂肪胺、芳香胺、巯基衍生物取代、B环7位的乙酰氨基被各种酰胺置换,以及在C_(10)位和C_7位同时修饰。本文主要介绍近5年来秋水仙碱结构修饰的研究进展。     

抗肿瘤多药耐药微管蛋白调节剂的研究进展

2015年,全世界有超过800万人死于肿瘤。传统化疗药物仍广泛应用于临床一线,但超过50%的肿瘤对此类药物产生明显的耐药性。微管蛋白调节剂已成为临床证实有效的抗癌药物。然而,紫杉醇、长春碱等传统微管蛋白调节剂也会产生严重耐药。近年来,研究发现作用于微管蛋白秋水仙碱位点的微管蛋白调节剂对抗肿瘤多药耐药具有很好的效果。本文综述近年来此类抗肿瘤多药耐药微管蛋白调节剂的研究进展。     

作用于秋水仙碱结合位点的微管蛋白抑制剂研究进展

微管是细胞骨架的主要组成部分并在细胞分裂过程中起着重要作用,因此微管蛋白成为抗癌药物的重要靶点之一,作用于微管系统的微管蛋白抑制剂现已成为一类有效的抗肿瘤药物。由于微管蛋白上秋水仙碱位点的空腔体积较小且相应抑制剂的结构较为简单,因而近年来关于其抑制剂的研究也备受关注。本文总结了多种不同结构类型的作用于秋水仙碱位点的抑制剂及其近年来的一些研究进展。     

作用于秋水仙碱位点的微管蛋白抑制剂的研究进展

微管是细胞骨架的主要组成部分,在维持细胞形态、细胞分裂、信号转导等过程中起着重要作用,因此,微管蛋白是一个非常有前景的新型化疗药物的靶标。秋水仙素结合位点抑制剂(CBSIs)通过抑制微管蛋白聚合和抑制微管形成发挥生物效应。近年来,人们对作用于此靶点的抑制剂开展了一系列的研究,并且取得了一定的进展,本文总结了多种不同结构类型的作用于秋水仙碱位点的抑制剂及其研究概况。     

微管蛋白秋水仙碱位点抑制剂研究进展

微管蛋白是细胞骨架的主要成分,参与了细胞过程的许多环节。秋水仙碱位点抑制剂（CSIs）是一类重要的微管蛋白聚合抑制剂。目前已经有许多CSIs作为抗肿瘤药物被发现或设计、合成,并取得了很大的进展。本研究主要就CSIs的作用机制、共同结构特征以及各种类型CSIs的构效关系作一综述。     

文蛤多肽抑制肿瘤细胞微管蛋白聚合

目的探讨文蛤多肽(Mere15)抑制人肺癌A549细胞增殖作用及其机制。方法 MTT比色法检测细胞增殖抑制率;流式细胞仪分析细胞周期分布的变化;微管蛋白免疫荧光检测技术检测Mere15对微管蛋白聚合的影响;Western blot检测Mere15对p21蛋白表达的影响。结果 Mere15可抑制A549细胞生长,抑制率呈剂量和时间依赖性;随着处理时间的增加,A549细胞G2/M期比例逐渐升高,微管蛋白聚合受到抑制,p21蛋白表达水平逐渐升高。结论 Mere15具有抑制A549细胞增殖的作用,其机制可能与抑制微管蛋白聚合有关。     

微管抑制剂那可丁及其衍生物的抗肿瘤作用研究进展

过去几十年中，那可丁一直被用作镇咳药。近年来发现那可丁及其衍生物可作用于微管，抑制其动态不稳定性，从而干扰肿瘤细胞的有丝分裂，起到抗肿瘤作用。体内实验研究发现，那可丁及其衍生物抗肿瘤活性高、广谱、毒副作用不明显，有望被开发为抗肿瘤新药。     

可抑制微管聚合的微生物来源的新抗肿瘤活性物质--cryptophycin

cryptophycin是从蓝藻的培养物中分离得到的一种能抑制微管生成的新型抗肿瘤活性物质,对多种肿瘤有活性。cryptophycin直接与微管蛋白作用,抑制微管生成,破坏微管动态装配,从而换制有丝分裂纺锤体的形成,进而影响细胞增殖。本文对cryptophycin的来源、结构、生物活性、作用机制以及构效关系等方面进行了综述。     

作用于微管的抗肿瘤药物研究进展

以微管为作用靶点的药物是一类重要的抗肿瘤药物。独特的作用机制和良好的治疗效果使其一直成为研究的热点。近年来，有关它们的作用机制、结合构象、结合位点及构效关系得到了更加深入细致的研究。本文从以上几个方面综述了这类药物的研究进展。     

可抑制微管聚合的微生物来源的新抗肿瘤活性物质——cryptophyci

cryptophycin是从蓝藻的培养物中分离得到的一种能抑制微管生成的新型抗肿瘤活性物质 ,对多种肿瘤有活性。cryptophycin直接与微管蛋白作用 ,抑制微管生成 ,破坏微管动态装配 ,从而抑制有丝分裂纺锤体的形成 ,进而影响细胞增殖。本文对 cryptophycin的来源、结构、生物活性、作用机制以及构效关系等方面进行了综述。     

Tubulin as an antiprotozoal drug target

Since tubulin is a known anticancer and anthelmintic drug target, the investigation of protozoal tubulin could lead to the development of new antiparasitic drugs. This review outlines the current state of knowledge concerning drug-mammalian tubulin interactions, the effects of antimicrotubule agents on parasites and parasite tubulin, and our current hypotheses regarding the development of selective ligands for protozoal tubulin as antiparasitic drug candidates.     

Immunoconjugates of Soybean Bowman-Birk Protease Inhibitor as Targeted Antitumor Polymeric Agents

To enhance the antitumor potential of soybean Bowman-Birk inhibitor (BBI), the conjugate of BBI with an antibody via a macromolecular carrier was prepared. Clinical dextran (D) was used as a biocompatible biodegradable carrier for co-immobilization of BBI and antibody. A model immunoglobulin isolated from sheep serum (slgG), raised against human IgM was utilized to develop the procedure of immunoconjugate synthesis. The molar ratio of the ingredients in the conjugate was the following BBI:D:sIgG=9:1:1. Comparison of the dose response curves for the native sIgG and the BBI-D-sIgG conjugate indicated that sIgG completely retained its specific activity (>90%) after modification with dextran. The determination of the K_i, values for chymotrypsin interaction with the native BBI and the BBI-D-sIgG conjugate indicated high anti-chymotrypsin activity. In the next step, the monoclonal antibody (ICO 25 MAb) against the mucin-like human epithelial membrane antigen was used for conjugation as it is the most universal vector for targeting different agents to human tumors of epithelial origin. The influence of conjugation on the specificity of the Mab reaction with its antigen was studied. The conjugated MAb reacted with tumor cells of different epithelial genesis (breast, lung, gastric, ovarian and uterus tumors), but did not react with tumor cells of non-epithelial origin. It was shown that BBI-D-ICO 25 MAb conjugate has almost the same immunohistochemical activity as non-conjugated MAb. These results demonstrated the feasibility of exploiting the activities of covalently bound BBI and ICO 25 MAb for anticarcinogenic agent targeting.     

Solid-State Phase Transitions of AG337, an Antitumor Agent

The object of this investigation was to perform detailed solid-state characterization studies on the different solid forms of AG337 and to determine the conditions of their interconversions. Solid-state characterization was done using differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), hot stage microscopy, Karl Fischer titrimetry, ambient and variable temperature X-ray powder diffractometry (XRD) and TGA coupled with FTIR (TGA/FTIR). In addition to five polymorphic forms of the anhydrate (I_αto I_ε), a hemihydrate (C₁₄H₁₂N₄OS· 2HCl · 0.5H₂O, II), a monohydrate (C₁₄H₁₂N₄OS · 2HCl · H₂O; III), as well as a dihydrate (C₁₄H₁₂N₄OS · 2HCl · 2H₂O; IV) were identified. The ‘as is’ anhydrate, Iα, resisted water uptake until stored at 98% RH (room temperature), where it transformed directly to IV. II and III transformed to IV at RH values ≥ 7.6 and 84% respectively. Heating II and III to 130°C in the variable temperature XRD resulted in the formation of I_β and I_γ respectively. On the other hand, I_δ and I_ε were obtained when II and III were respectively stored at 60°C under vacuum. Variable temperature XRD, by providing information about the solid-state as a function of temperature, assisted in the interpretation of the DSC and TGA results. TGA/FTIR provided direct evidence that the thermal events observed in the temperature ranges of 25–150°C and 200–250°C were due to loss of water and loss of hydrogen chloride respectively. In addition to the conventional analytical techniques such as XRD, DSC, TGA and KFT, two other techniques, (variable temperature XRD and TGA/FTIR), were very useful in these solid-state characterization studies.     

Developmental Toxicity of CI-921, an Anilinoacridine Antitumor Agent

CI-921, an anilinoacridine compound active against leukemicand solid tumors, was evaluated for potential developmentaltoxicity. Intravenous injections of CI-921 in dextrose weregiven to female Sprague-Dawley rats (0.1, 0.5, and 1.0 mg/kg)on Gestation Days (GD) 6–15 and to female New ZealandWhite rabbits (0.1, 1.0 and 2.0 mg/kg) on GD 6–18. Appropriatevehicle and untreated controls were included. Maternal and fetalparameters, including external, visceral, and skeletal malformationsand variations, were assessed. Treatment of rats with 1.0 mg/kgresulted in maternal toxicity, manifested as reduced body weightgain and food consumption during and after treatment. Reducedfetal body weight, an increased incidence of stunted fetuses,malformations of the axial and appendicular skeleton, microphthalmia,and an increased number of anatomical variations (includinganomalies of the axial skeleton and apparent hydronephrosis)also occurred in rats at 1.0 mg/kg. Treatment of rabbits resultedin no apparent maternal toxicity. However, reduced fetal bodyweight, agenesis of the azygous lobe of the lung, and an increasedincidence of variations of the axial skeleton occurred at 2.0mg/kg in rabbits. These results indicate that CI-921, at thehighest dose tested in each species, produced developmentaltoxicity in the presence of maternal toxicity in rats, but inthe absence of maternal toxicity in rabbits.     

Biological Evaluation and Molecular Modelling Study of Podophyllotoxin Derivatives as Potent Inhibitors of Tubulin Polymerization

Microtubules are considered as important targets of anticancer therapy. Podophyllotoxin and its structural derivative are major microtubule‐interfering agents with potent anticancer activity. In this study, we reported the anticancer effects of 10 representative podophyllotoxin derivatives on a panel of four human cancer cell lines. Deoxypodophyllotoxin ( 6b ) and β‐apopicropodophyllotoxin ( 6g ) elicited strong antiproliferative effects (IC₅₀) at a range of 0.0073–0.14 μm . Direct tubulin depolymerization assay in vitro was also performed. Results showed that that the two compounds can inhibit microtubule polymerization. Experimental measurements were also supported by molecular dynamic simulations, which showed that the two active compounds formed interactions with the colchicine‐binding site of the tubulin protein. Our results helped us understand the nature of tubulin binding and determine the core design of a new series of potent inhibitors of tubulin polymerization.     

Photoinduced Particulate Matter in a Parenteral Formulation for Bisnafide,an Experimental Antitumor Agent

This paper assesses the cause of particulate formation in vials of the experimental antitumor agent bisnafide and investigates pharmaceutical techniques to reduce the number of particulates in the product. Solution preparation and particulate isolation were performed under Class 100 laminar air flow. Reversed-phase HPLC and infrared microscopy were used to characterize drug and isolated particulate matter, whereas a Hiac particle counter was used to quantify the particulate matter. Particulate matter was observed following agitation of the drug solutions and was found to be associated with specific lots of drug substance. HPLC of the isolated particulate matter indicated that the particulates consisted largely of bisnafide and impurities that were identified as the products of photodegradation, confirmed to be the result of the photolytic cleavage of bisnafide to form a poorly soluble aldehyde. The aldehyde may, in turn, interact with bisnafide molecules to form the particulate matter as suggested by the observed pH-dependent reversibility of the particulate phenomenon. The particulate matter could be reduced by protecting solutions of bisnafide from light during chemical synthesis and production of the dosage form and, alternatively, by reducing the solution pH to 3.0 or less, addition of surfactants below their critical micelle concentration, and removal of impurities by froth flotation of the bisnafide solutions.     

抗肿瘤药伏立诺他的合成

目的伏立诺他的合成方法。方法以辛二酸为原料,通过连续两步混合酸酐法制得抗肿瘤药伏立诺他。结果合成的目标化合物经核磁共振氢谱、核磁共振碳谱、质谱及红外光谱确证。结论本合成通过两步得到目标化合物,收率约为41%。     

抗肿瘤药Pomalidomide的合成

N-(叔丁氧羰基)-L-谷氨酰胺(2)经闭环、脱保护制得3-氨基-2,6-哌啶二酮三氟乙酸盐(4).另用3-硝基邻苯二甲酸(5)脱水制得3-硝基邻苯二甲酸酐(6).4和6经缩合、铁粉/浓盐酸还原制得免疫调节剂类抗肿瘤药3-氨基-N-(2,6-二氧代-3-哌啶基)-邻苯二甲酰亚胺,以5计总收率约35%.     

Unusual Reactivity of a Potent Platinum-Acridine Hybrid Antitumor Agent

The formation of unusual seven-membered, sterically overloaded chelates [Pt(en)(L/L′)](NO(3))(2) (4a/4b) from the corresponding potent hybrid antitumor agents [PtCl(en)(LH/L′H)](NO(3))(2) (3a/3b) is described, where en is ethane-1,2-diamine and L(H) and L′(H) are (protonated) N-(2-(acridin-9-ylamino)ethyl)-N-methylpropionimidamide and N-(2-(acridin-9-ylamino)ethyl)-N-methylacetimidamide, respectively. Compounds 3a and 3b inhibit H460 lung cancer cell proliferation with IC(50) values of 12 ± 2 nM and 2.8 ± 0.3 nM, respectively. The new derivative 3b proves to be not only the most cytotoxic platinum-acridine hybrid of this kind, but also one of the most potent platinum-based anticancer agents described to date. The chelates 4a and 4b do not undergo ligand substitution reactions with nucleobase nitrogen and cysteine sulfur and do not intercalate into DNA. Despite their inertness, the two chelates appear to maintain micromolar activity in H460 cells. The results are discussed in the context of potential DNA-mediated and DNA-independent cell kill mechanisms and the potential use of the chelates as prodrugs.