紫杉醇聚合物胶束及其抗肿瘤活性研究

目的 以聚己内酯-聚乙二醇-聚己内酯（PCL-PEG-PCL）为载体材料,制备载紫杉醇聚合物胶束,并评价其对EMT-6乳腺癌的抗肿瘤效果.方法 采用薄膜-超声法制备载紫杉醇聚合物胶束并对其进行表征;采用差示扫描热分析法（DSC）分析紫杉醇在载药聚合物胶束中的分散状态;采用MTT法研究紫杉醇聚合物胶束对EMT-6乳腺癌细胞的细胞毒性;建立荷EMT-6乳腺癌小鼠模型,以市售紫杉醇注射液为对照,研究紫杉醇聚合物胶束的体内抗肿瘤活性.结果 紫杉醇聚合物胶束为表面粗糙的球形,具有明显核壳结构,平均粒径为93nm;DSC研究结果表明,将紫杉醇制成缓释纳米粒后其结晶状态发生了变化,以无定型状态存在于聚合物胶束中;MTT研究表明,在相同紫杉醇含量下,紫杉醇聚合物胶束的细胞毒性低于市售紫杉醇／聚氧乙烯蓖麻油注射剂;体内抗肿瘤活性研究表明,紫杉醇聚合物胶束对小鼠EMT-6乳腺癌具有明显抑制作用,相同给药剂量下其抑瘤效果优于紫杉醇注射剂（肿瘤抑制率：85.79％ vs 63.37％,P＜0.05）.结论 制备的载紫杉醇聚合物胶束高效低毒,是一种有潜力的可用于肿瘤治疗的纳米载药体系.     

脂肪干细胞携载汉黄芩苷聚己内酯-聚乙二醇胶束的制备

背景:汉黄芩苷已被证明有抗炎、神经保护等多种药理活性作用,但其半衰期短、难溶于水,有机溶剂溶解后不良反应大.研究发现,聚己内酯-聚乙二醇能够结合高度疏水的药物,解决药物难溶问题且可以达到缓释的效果,但无法精确靶向到达损伤部位,制成胶束后因其尺寸小,可以穿透细胞膜.目的:制备汉黄芩苷聚己内酯-聚乙二醇胶束以及脂肪干细胞携...     

聚乙二醇-b-聚己内酯/聚己内酯单分散电喷微球的制备与亲水性研究

用静电喷雾法制备单分散性良好、亲水性的聚乙二醇-b-聚己内酯/聚己内酯(PEG-b-PCL/PCL)电喷微球。将聚乙二醇-b-聚己内酯(PEG-b-PCL)、聚己内酯(PCL)与氯仿混合磁力搅拌3 h后,采用静电喷雾的方法,以双亲(PEG-b-PCL)含量、流速、电压为变量,研究微球形态大小、粒径分布的变化,并研究微球亲水性随双亲含量的变化程度及微球在水中的分散性。双亲含10%～20%、流速1 mL/h、电压10 kV时能得到成球性佳、粒径5～6 μm的单分散性良好的微球,粒径的变异系数为15%～21%;双亲含量增至30%,微球之间由较多的纤维连接;双亲含量由0增至20%时,接触角由126.2°±4.8° 降至29.9°±4.9°,差异具有统计学意义(P<0.05),通过改变双亲含量能有效改善微球的亲水性,同时,加入10%～20%双亲的微球在水中分散性佳,能形成均匀的混悬液。PEG-b-PCL/ PCL能得到单分散、亲水性佳的微球,为进一步制备载药微球提供条件。     

载紫杉醇聚己内酯-聚乙二醇-聚己内酯胶束的制备及药代动力学研究

目的制备新型可注射用载紫杉醇聚己内酯-聚乙二醇-聚己内酯(PCL-PEG-PCL)胶束,并评价和比较其与市售紫杉醇注射液在大鼠体内的药代动力学性质。方法以PCL-PEG-PCL为载体材料,通过薄膜-水化-超声法制备出载紫杉醇PCL-PEG-PCL胶束,并对其进行表征。以市售紫杉醇注射液为对照,采用SD大鼠尾静脉注射后观察载紫杉醇PCLPEG-PCL胶束的体内药代动力学,并用DAS 2.0药代动力学数据软件计算相关参数。结果载紫杉醇PCL-PEG-PCL胶束呈大小均匀的球形,具有明显的核壳结构;平均粒径为93 nm,多分散系数为0.19;载药量为28.98%,药物包封率为94.36%。体外释放研究表明,载紫杉醇PCL-PEG-PCL胶束具有缓释效果。药代动力学研究表明,两种制剂均符合二房室模型,市售紫杉醇注射液和紫杉醇聚合物胶束消除半衰期(t1/2β)分别为(1.96±0.27)h和(12.65±1.77)h,平均滞留时间(MRT)分别为(0.93±0.19)h和(11.18±1.41)h,体内总清除率(CL)分别为(0.44±0.05)L·kg/h和(0.10±0.01)L·kg/h,药-时曲线下面积(AUC0-∞)分别为(17.15±2.35)mg·h/L和(73.82±10.38)mg·h/L。结论成功制备了新型可注射用载紫杉醇PCL-PEG-PCL胶束,药代动力学研究表明,所研制的载紫杉醇PCL-PEG-PCL胶束明显延长紫杉醇在血液中的循环时间及消除半衰期,显著提高生物利用度,是一种有潜力的紫杉醇缓控释新剂型。     

紫杉醇聚己内酯／泊洛沙姆188载药纳米粒及其抗肿瘤活性

目的利用聚己内酯（PCL）与亲水性添加剂泊洛沙姆188（F68）共混物作为载体材料与抗癌药物紫杉醇组成纳米粒缓释载药系统,并评价其在裸鼠人乳腺癌B37实体瘤模型中的抗肿瘤效果。方法采用超声乳化／溶剂挥发法制备紫杉醇PCL/F68载药纳米粒：对紫杉醇PCI／F68载药纳米粒进行表征及高压液相色谱法（HPLC）测定包封率和体外释放度：利用差示扫描热分析（DSC）法分析紫杉醇在PCL／F68载药纳米粒中的分散状态;评价紫杉醇PCL／F68载药纳米粒在裸鼠人乳腺癌B37实体瘤模型中的抗肿瘤活性．结果紫杉醇PCL/F68载药纳米粒呈现规整的球形：平均粒径为150．50nm（标准差25．41nm）．多分散系数为O．18。紫杉醇PCI仃68纳米粒的载药量为18％,药物包封率为84-36％。紫杉醇PCIJF68载药纳米粒体外药物释放研究表明在50d的释放周期内累计释放量约为49％,接近零级释放（R=0．998）。体内抗肿瘤活性实验研究表明．紫杉醇PCL/F68载药纳米粒对裸鼠人乳腺癌B37实体瘤生长具有明显抑制作用。结论肿瘤局部注射紫杉醇PCL/F68载药纳米粒能够有效地抑制肿瘤的生长,     

一种可生物降解温度敏感型聚乙二醇-聚己内酯-聚乙二醇水凝胶的合成和表征

合成了一系列分子量较低的聚乙二醇．聚己内酯-聚乙二醇（Poly（ethylene glycol）-Polycaprolactone-Poly（ethylene glycol），PEG-PCL—PEG）三嵌段共聚物。分别采用FTIR和1H—NMR对其结构进行了表征。所合成的PEG-PCL-PEG共聚物具有良好的水溶性，当水溶液浓度高于临界凝胶浓度（Critical gel concentration，CGC）时，随着温度的变化聚合物水溶液会呈现特有的凝胶-溶胶转变。研究了共聚物亲水疏水链段的比例和长度，以及热历史等对凝胶-溶胶转变行为的影响。通过调节上述条件，可以在一定程度上拓宽凝胶-溶胶转变温度范围，有助于PEG—PCL-PEG水凝胶在可注射药物控制释放系统等方面的应用。     

紫杉醇聚己内酯／泊洛沙姆188共混载药微球及其抗肿瘤活性

目的本研究首次尝试利用聚己内酯（PCL）与亲水性添加剂泊洛沙姆188（Pluronic F68,F68）共混物作为载体材料与抗癌药物紫杉醇组成微球缓释载药系统。方法采用乳化,溶剂挥发法制备紫杉醇PCL/F68共混微球;考察紫杉醇PCL／F68共混微球的表面形态、平均粒径、包埋率及体外释放性能：利用DSC法分析紫杉醇在PCL／F68共混徽球中的分散状态;考察紫杉醇PCL/F68共混微球在小鼠肝癌H22腹水瘤模型中的抗肿瘤活性。结果表明载体材料中的亲水性添加剂F68可在微球表面形成孔状结构,F68的加入提高了紫杉醇从PCL／F68共混载药微球的释放并获得了接近恒定的释放性能;在小鼠肝癌H22腹水瘤模型中。紫杉醇PCL／F68共混载药微球对肿瘤生长具有抑制作用,荷瘤小鼠生存期明显延长。结论以PCL/F68共混物为载体制备的紫杉醇控释微球具有较高的释放能力和明显的控释效果．     

聚己内酯埋植剂的制备及药物通透性研究

目的制备聚己内酯（PCL）长效药物缓释制剂,优化药物缓释效果,并研究PCL埋植剂的药物通透性.方法 合成分子质量为（8～16）×104 u含有普朗尼克F68的PCL,用挤出法制备不同壁厚的PCL长效缓释埋植剂.将左炔诺孕酮（LNG）装入PCL管封装,制成LNG药囊.通过高效液相色谱法测定LNG的释放效果,考察PCL的分子质量及PCL管壁厚度对LNG通透性的影响.结果 当PCL分子质量为（8～16）×104u时,对LNG通透性无显著影响.PCL管壁厚在0.20～0.40 mm时,对LNG通透性亦无显著影响;当壁厚小于0.15 mm时,LNG通透性显著提高.结论 PCL埋植剂对LNG具有通透性,可通过改变PCL管壁厚度增加药物通透性.     

调整紫杉醇化疗预处理方案的临床观察简

 目的 观察不同紫杉醇预处理方案化疗的用药安全性和不良反应,探索新的紫杉醇化疗预处理方案 方法 紫杉醇 135~175mg/m2,联合铂类药物,21d/周期,输注紫杉醇前用2种预处理方案,比较应用2种预处理方案化疗的不良反应 结果 77例应用调整预处理方案的患者与78例标准预处理方案患者的急性过敏反应、神经毒性、胃肠道反应发生率比较均无差异 结论 调整后的紫杉醇预处理方案安全、有效,与标准预处理方案比较无差异。     

新型聚己内酯/磷酸钙支架的制备及生物相容性研究

探讨新型聚己内酯(PCL)/磷酸钙(CPC)复合材料支架的制备方法及对骨髓基质细胞(BMSCs)的生物相容性。采用溶液共混法,利用可溶盐晶体做造孔剂,制备PCL/CPC复合材料支架,以单纯PCL和CPC支架为对照组,Q800型动态力学分析仪进行动态力学性能试验(DMA),采用排水法测量孔隙率;灭菌后通过与犬BMSCs体外共同培养后细胞形态、生长曲线、碱性磷酸酶(ALP)染色和半定量及骨钙素(OC)半定量等方法检测细胞在支架材料上的黏附、增殖及成骨分化情况,动物体内异位成骨检测其成骨情况。结果显示,复合材料的储能模量在PCL/CPC比例为7:3时达到最大,制得的材料孔径为250～350μm,多孔支架的孔隙率为70%～80%;BMSCs在新型PCL/CPC组、CPC组支架表面分布均匀,生长增殖明显较PCL组活跃(P<0.05);PCL/CPC组、CPC组BMSCs成骨行为与PCL组之间有显著差异(P<0.05)。动物体内异位成骨检测提示,4周时PCL/CPC组为13.78%±1.60%、CPC组BMSCs为15.29%±1.20%,成骨显著强于PCL组BMSCs的7.56%±2.20%(P<0.05),表明PCL和CPC的复合明显改善了两种材料的缺陷,获得的PCL/CPC支架具有良好的生物相容性,可与BMSCs共同构建具有成骨能力的三维立体组织工程化骨。     

Design and synthesis of pH-sensitive polymeric micelles for oral delivery of poorly water-soluble drugs

pH-sensitive polymer poly (polylactide-co-methacrylic acid)–b-poly (acrylic acid) was synthesized using atom transfer radical polymerization and ring-opening polymerization and characterized by gel permeation chromatography and ¹H NMR. The polymers can self-assemble to form micelles in aqueous medium, which respond rapidly to pH change within the gastrointestinal relevant pH range. Critical micelle concentrations and pH response behavior of the polymeric micelle were investigated. Water-insoluble drug nifedipine was loaded and the drug-loading content can be controlled by tuning the composition of the polymers. The in vitro release studies indicate pH sensitivity enabled rapid drug release at the environment of simulated intestinal fluid (pH 7.36), the cumulative released amount of NFD reached more than 80% within 24 h, while only 35% in the simulated gastric fluid (pH 1.35). All the results showed that the pH-sensitive P(PLAMA-co-MAA)–b-PAA micelle may be a prospective candidate as oral drug delivery carrier for hydrophobic drugs with controlled release behavior.     

白藜芦醇聚合物胶束的制备及质量评价

目的制备白藜芦醇(RES)聚合物胶束并对其进行质量评价。方法采用薄膜分散法,以聚乙烯己内酰胺-聚乙酸乙烯酯-聚乙二醇接枝共聚物(SPS)和D-α生育酚聚乙二醇1000琥珀酸酯(TPGS)为载体材料,制备白藜芦醇聚合物胶束(RES-SPS-TPGS-PMs);采用纳米粒度分析仪、差示扫描量热法(DSC)及傅立叶变换红外光谱法(FTIR)对其进行表征;采用高效液相色谱法测定聚合物胶束的包封率和载药量;采用动态膜透析法考察载药胶束的体外释放特性。结果制备的胶束平均粒径为(52.4±0.66)nm,多分散指数为0.06±0.01,包封率为(97.12±9.08)%,载药量为(2.37±0.22)%。白藜芦醇在聚合物胶束中可能以无定型或分子的形式存在,且白藜芦醇与载体材料之间形成了氢键。体外释放结果表明白藜芦醇聚合物胶束具有明显的缓释效果。结论该胶束制备工艺简单,其粒径、包封率、载药量可控,具有缓释作用。     

Synthesis,characterization, and in vitro evaluation of TRAIL-modified,cabazitaxel -loaded polymeric micelles for achieving synergistic anticancer therapy

Abstract

Combination therapy of two or more drugs has gradually become of outmost importance in cancer treatment. Cabazitaxel (CTX) is a taxoid drug and tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) is a member of TNF superfamily. In this study, we prepared TRAIL-modified and CTX-loaded polymer micelle (TRAIL-M-CTX). This nanoparticle was self-assembled from biodegradable amphiphilic copolymers, monomethoxyl poly(ethylene glycol)–b-poly(DL-lactide) (mPEG-PLA) and COOH-PEG-PLA, via a nanoprecipitation method and were modified with the TRAIL protein, resulting in a particle size of 39.75 ± 0.17 nm in diameter and a drug encapsulation efficiency of 95.52 ± 1.69%. The successful coupling was confirmed by ¹H NMR, FTIR spectroscopy, and DLS article size measurement. Pharmacodynamic analysis in two human cancer cell lines with different TRAIL sensitivities showed that TRAIL-M-CTX has a significantly better anticancer efficacy than the individual CTX and TRAIL protein. Importantly, TRAIL-M-CTX showed synergistic effects against TRAIL-insensitive cells (MCF-7). A study of cellular uptake implied that the modified micelles were internalized into MCF-7 cells more effectively than unmodified micelles, owing to the coupled TRAIL protein. A cell cycle assay of MCF-7 cells revealed that TRAIL-M-CTX significantly increased the sub-G1 population compared with CTX or TRIAL, thus, facilitating cancer cell apoptosis. These results suggest that TRAIL-M-CTX micelles have potential as a cancer chemotherapy formulation.     

The efficiency of tumor-specific pH-responsive peptide-modified polymeric micelles containing paclitaxel

The acidic pH in tumor tissues could be used for targeting solid tumors. In the present study, we designed a tumor-specific pH-responsive peptide H₇K(R₂)₂, which could respond to the acidic pH in tumor tissues, and prepared H₇K(R₂)₂-modified polymeric micelles containing paclitaxel (PTX-PM-H₇K(R₂)₂) in order to evaluate their potential targeting of tumor cells and tumor endothelial cells and their anti-tumor activity in mice with tumor cells. PTX-PM-H₇K(R₂)₂ was prepared by a thin-film hydration method. The in vitro release of PTX from PTX-PM-H₇K(R₂)₂ was tested. The in vitro targeting characteristics of H₇K(R₂)₂-modified polymeric micelles on HUVEC (human umbilical vein endothelial cells) and MCF-7 (human breast adenocarcinoma cells) were evaluated. The in vivo targeting activity of H₇K(R₂)₂-modified polymeric micelles and the in vivo anti-tumor activity of PTX-PM-H₇K(R₂)₂ were also investigated in MCF-7 tumor-bearing mice. The released PTX from the PTX-PM-H₇K(R₂)₂ was not affected by the pH. The targeting activity of the H₇K(R₂)₂-modified polymeric micelles was demonstrated by in vitro flow cytometry and confocal microscopy as well as in vivo biodistribution. PTX-PM-H₇K(R₂)₂ produced very marked anti-tumor and anti-angiogenic activity in MCF-7 tumor-bearing mice in vivo.     

Gene therapy of endometriosis introduced by polymeric micelles with glycolipid-like structure

To reduce the side effects and improve the lack of clinical treatment countermeasures in endometriosis chemotherapy, a polymeric micelle gene delivery system composed of lipid grafted chitosan micelles (CSO-SA) and the pigment epithelium derived factor (PEDF) was designed. Due to the cationic property, the glycolipid-like micelles could compact the PEDF to form complexes nanoparticles. The complexes nanoparticles with an N/P at 9.6 had 135.6 nm volume average hydrodynamic diameters with a narrow size distribution, and 6.4 ± 0.1 mV surface potential. PEDF can be distributed to endometriotic lesions in a rat model of peritoneal endometriosis mediated by CSO-SA via the intravenous injection. It showed that the CSO-SA/PEDF nanoparticles gene therapy caused decrease in the sizes of the endometriotic lesions and atrophy and degeneration of ectopic endometrium significantly. And it showed no toxicity to the reproductive organs under electron microscope observation. In addition, a reduction in microvessel density labeled by Von Willebrand factor was observed and no decrease in α-Smooth Muscle Actine-positive mature vessels. And the index of apoptotic was increased significantly in endometriotic lesions of CSO-SA/PEDF group. So, glycolipid-like structure micelles mediated PEDF gene delivery system could be used as an effective treatment approach for endometriosis disease.     

Preparation of hepatitis B polypeptide micelles from human carrier plasma

Water-soluble protein micelles consisting of the 28,000 (gp28) and 23,000 (p23) molecular weight polypeptide complex of hepatitis B surface antigen can be readily prepared from human plasma containing the surface antigen and other markers of infection with hepatitis B virus. The antigenic activity of the polypeptides was preserved throughout the process of solubilisation and reassociation into micelles. Such preparations are therefore eminently suitable as ‘second generation’ hepatitis B vaccines.     

Synthesis and cytotoxicity of brefeldin A conjugated monomethoxy-poly(ethylene glycol)-b-poly(L-lactide) polymeric micelles

A diblock copolymer of monomethoxy-poly(ethylene glycol)-b-poly(L-lactide) (MePEG-PLLA)/brefeldin A (BFA) conjugate was synthesized by the reaction of carboxyl-terminated copolymer MePEG-PLLA with BFA in the presence of dicyclohexylcarbodiimide and dimethylaminopyridine. The conjugation efficiency was found to be 95%. Its structure was confirmed by ¹H nuclear magnetic resonance and gel permeation chromatography. The MePEG-PLLA/BFA conjugate could self-assemble into micelles in aqueous solutions with a low critical micelle concentration of 1.8?×?10^?3?g/L. Dynamic light scattering and transmission electron microscopy analyses of the MePEG-PLLA/BFA micelles revealed their spherical structure with an average diameter of 120?nm. The release profiles of BFA in PBS were measured by high performance liquid chromatography (HPLC), demonstrating that the controlled release of BFA can be gained for long time. The in vitro antitumor activity of the conjugate micelles against human liver carcinoma HepG2 cells was evaluated by 3-(4,5-dimethylthiazolyl-2)-2,5-diphenyl tetrazolium bromide method, and the results showed that BFA can be released from the conjugate micelles without losing cytotoxicity.     

Co-delivery of thioridazine and doxorubicin using polymeric micelles for targeting both cancer cells and cancer stem cells

In this study, thioridazine (THZ), which was reported to kill cancer stem cells, was used in a combination therapy with doxorubicin (DOX) to eradicate both cancer cells and DOX-resistant cancer stem cells to mitigate the reoccurrence of the disease. Both THZ and DOX were loaded into micelles with sizes below 100 nm, narrow size distribution and high drug content. The micelles were self-assembled from a mixture of acid-functionalized poly(carbonate) and poly(ethylene glycol) diblock copolymer (PEG-PAC) and urea-functionalized poly(carbonate) (PUC) and PEG diblock copolymer (PEG-PUC). The drug-loaded mixed micelles (MM) were used to target both cancer cells and stem cells via co-delivery. Cancer stem cells were sorted by a side population assay from BT-474 and MCF-7 human breast cancer cell lines, and identified by CD44+/CD24− phenotype. The cytotoxicity of various formulations was evaluated on the sorted cancer stem cells (side population SP cells), sorted non-stem-like cancer cells (non-side population NSP cells) and unsorted cancer cells. Antitumor activity was also evaluated on BT-474 xenografts in nude mice. As compared with NSP cells, DOX suppressed SP cell growth less effectively, while THZ and THZ-MM were more effective in the inhibition of SP cells. A stronger inhibitory effect was observed on SP cells with the co-delivery of free DOX and THZ or DOX-MM and THZ-MM as compared to free DOX or DOX-MM. THZ and THZ-MM were capable of lowering the population of SP cells in unsorted cells. In the BT-474 xenografts, the co-delivery of DOX-MM and THZ-MM produced the strongest antitumor efficacy, and both THZ and THZ-MM showed strong activity against cancer stem cells. This combination therapy may provide a promising strategy for breast cancer treatment by targeting both cancer cells and cancer stem cells.     

Matrix metalloproteinase 2-sensitive multifunctional polymeric micelles for tumor-specific co-delivery of siRNA and hydrophobic drugs

Co-delivery of hydrophilic siRNA and hydrophobic drugs is one of the major challenges for nanomaterial-based medicine. Here, we present a simple but multifunctional micellar platform constructed by a matrix metalloproteinase 2 (MMP2)-sensitive copolymer (PEG-pp-PEI-PE) via self-assembly for tumor-targeted siRNA and drug co-delivery. The micellar nanocarrier possesses several key features for siRNA and drug delivery, including (i) excellent stability; (ii) efficient siRNA condensation by PEI; (iii) hydrophobic drug solubilization in the lipid “core”; (iv) passive tumor targeting via the enhanced permeability and retention (EPR) effect; (v) tumor targeting triggered by the up-regulated tumoral MMP2; and (vi) enhanced cell internalization after MMP2-activated exposure of the previously hidden PEI. These cooperative functions ensure the improved tumor targetability, enhanced tumor cell internalization, and synergistic antitumor activity of co-loaded siRNA and drug.