FF‐10832 enables long survival via effective gemcitabine accumulation in a lethal murine peritoneal dissemination model

Chemotherapy has been the treatment of choice for unresectable peritoneal dissemination; however, it is difficult to eradicate such tumors because of poor drug delivery. To solve this issue, we developed FF‐10832 as liposome‐encapsulated gemcitabine to maintain a high concentration of gemcitabine in peritoneal tumors from the circulation and ascites. A syngeneic mouse model of peritoneal dissemination using murine Colon26 cell line was selected to compare the drug efficacy and pharmacokinetics of FF‐10832 with those of gemcitabine. Despite the single intravenous administration, FF‐10832 treatment enabled long‐term survival of the lethal model mice as compared with those treated with gemcitabine. Pharmacokinetic analysis clarified that FF‐10832 could achieve a more effective gemcitabine delivery to peritoneal tumors owing to better stability in the circulation and ascites. The novel liposome‐encapsulated gemcitabine FF‐10832 may be a curative therapeutic tool for cancer patients with unresectable peritoneal dissemination via the effective delivery of gemcitabine to target tumors.     

Increasing the removal of protein‐bound uremic toxins by liposome‐supported hemodialysis

Protein‐bound uremic toxins (PBUTs) accumulate at high plasma levels and cause various deleterious effects in end‐stage renal disease patients because their removal by conventional hemodialysis is severely limited by their low free‐fraction levels in plasma. Here, we assessed the extent to which solute removal can be increased by adding liposomes to the dialysate. The uptake of liposomes by direct incubation in vitro showed an obvious dose‐response relationship for p‐cresyl sulfate (PCS) and indoxyl sulfate (IS) but not for hippuric acid (HA). The percent removal of both PCS and IS but not of HA was gradually increased with the increased concentration of liposomes in a rapid equilibrium dialysis setup. In vitro closed circulation showed that adding liposomes to the dialysate markedly increased the dialysances of PBUTs without greatly altering that of urea and creatinine. In vivo experiments in uremic rats demonstrated that adding liposomes to the dialysate resulted in higher reduction ratios (RRs) and more total solute removal (TSR) for several PBUTs compared to the conventional dialysate, which was approximately similar to the addition of bovine serum albumin to the dialysate. These findings highlight that as an adjunct to conventional hemodialysis, addition of liposomes to the dialysate could significantly improve the removal of protein‐bound uremic solutes without greatly altering the removal of small, water‐soluble solutes.     

A novel liposome adjuvant DPC mediates Mycobacterium tuberculosis subunit vaccine well to induce cell-mediated immunity and high protective efficacy in mice

Tuberculosis (TB) is a serious disease around the world, and protein based subunit vaccine is supposed to be a kind of promising novel vaccine against it. However, there is no effective adjuvant available in clinic to activate cell-mediated immune responses which is required for TB subunit vaccine. Therefore, it is imperative to develop new adjuvant. Here we reported an adjuvant composed of dimethyl dioctadecylammonium (DDA), Poly I:C and cholesterol (DPC for short). DDA can form a kind of cationic liposome with the ability to deliver and present antigen and can induce Th1 type cell-mediated immune response. Poly I:C, a ligand of TLR3 receptor, could attenuate the pathologic reaction induced by following Mycobacterium tuberculosis challenge. Cholesterol, which could enhance rigidity of lipid bilayer, is added to DDA and Poly I:C to improve the stability of the adjuvant. The particle size and Zeta-potential of DPC were analyzed in vitro. Furthermore, DPC was mixed with a TB fusion protein ESAT6-Ag85B-MPT64(190-198)-Mtb8.4-Rv2626c (LT70) to construct a subunit vaccine. The subunit vaccine-induced immune responses and protective efficacy against M. tuberculosis H37Rv infection in C57BL/6 mice were investigated. The results showed that the DPC adjuvant with particle size of 400 nm and zeta potential of 40 mV was in good stability. LT70 in the adjuvant of DPC generated strong antigen-specific humoral and cell-mediated immunity, and induced long-term higher protective efficacy against M. tuberculosis infection (5.41 ± 0.38 log₁₀ CFU) than traditional vaccine Bacillus Calmette–Guerin (BCG) (6.01 ± 0.33 log₁₀ CFU) and PBS control (6.53 ± 0.26 log₁₀ CFU) at 30 weeks post-vaccination. In conclusion, DPC would be a promising vaccine adjuvant with the ability to stimulate Th1 type cell-mediated immunity, and could be used in TB subunit vaccine.     

肉苁蓉苯乙醇总苷脂质体对大鼠肝星状细胞增殖、凋亡及细胞周期的影响

目的：研究肉苁蓉苯乙醇总苷（CPhGs）脂质体对大鼠肝星状细胞（HSCs）增殖、凋亡、周期的影响及其相关分子机制。方法：HSCs分为空白对照组和CPhGs脂质体低、中、高浓度（分别为7.36、14.72、29.45 μg/mL）处理组。采用MTT法检测CPhGs脂质体对大鼠肝星状细胞增殖的影响；流式细胞术Annexin V-FITC/PI双染色法检测细胞凋亡状况，PI染色法检测大鼠肝星状细胞的周期变化；Western blot检测caspase-3、p27蛋白的表达变化。结果：与空白对照组比较，低、中、高3个剂量的CPhGs脂质体作用于HSCs后，均可抑制细胞的增殖（P < 0.05）；3个剂量的CPhGs脂质体均可促使大鼠肝星状细胞发生凋亡，使细胞阻滞在G0/G1期，上调caspase-3及p27蛋白的表达（P < 0.05）。结论：CPhGs脂质体对体外培养大鼠肝星状细胞有抑制增殖、促进凋亡、阻滞细胞周期的作用。其机制可能与CPhGs脂质体上调caspase-3和p27蛋白表达有关。     

Dibucaine in Ionic-Gradient Liposomes: Biophysical,Toxicological, and Activity Characterization

Administration of local anesthetics is one of the most effective pain control techniques for postoperative analgesia. However, anesthetic agents easily diffuse into the injection site, limiting the time of anesthesia. One approach to prolong analgesia is to entrap local anesthetic agents in nanostructured carriers (e.g., liposomes). Here, we report that using an ammonium sulphate gradient was the best strategy to improve the encapsulation (62.6%) of dibucaine (DBC) into liposomes. Light scattering and nanotracking analyses were used to characterize vesicle properties, such as, size, polydispersity, zeta potentials, and number. In vitro kinetic experiments revealed the sustained release of DBC (50% in 7 h) from the liposomes. In addition, in vitro (3T3 cells in culture) and in vivo (zebrafish) toxicity assays revealed that ionic-gradient liposomes were able to reduce DBC cyto/cardiotoxicity and morphological changes in zebrafish larvae. Moreover, the anesthesia time attained after infiltrative administration in mice was longer with encapsulated DBC (27 h) than that with free DBC (11 h), at 320 μM (0.012%), confirming it as a promising long-acting liposome formulation for parenteral drug administration of DBC.     

基于pH梯度载药技术的咪喹莫特脂质体的制备工艺研究

目的 根据咪喹莫特的理化性质,利用pH梯度主动载药技术制备脂质体,考察其性状、粒径、表面电荷及体外释药特征。方法 葡聚糖凝胶滤过法测定脂质体的包封率,以包封率与成型性为主要指标筛选制备方法,考察水化液的种类、pH值、离子强度及pH梯度载药、磷脂-胆固醇比例、脂药比、维生素E用量对包封率的影响;正交试验优化咪喹莫特脂质体的处方,考察脂质体样品在0~4℃下的稳定性。结果 按处方咪喹莫特50 mg、大豆卵磷脂400 mg、胆固醇130 mg、油酸10 mg、维生素E 5 mg、柠檬酸pH 2.5缓冲液5 mL,采用薄膜分散法工艺制备脂质体样品,并进行pH梯度主动载药,pH值调至7.0。制得的咪喹莫特脂质体呈白色均匀的混悬液,脂质体微粒圆整,分散性好,粒径（347±21）nm,包封率（81.2±1.9）%,Zeta电位（-12.19±1.7）mV。结论 pH梯度主动载药技术适于咪喹莫特脂质体的制备。     

紫杉醇脂质体与紫杉醇分别联合卡铂治疗卵巢癌疗效的Meta分析

摘 要 目的：系统评价紫杉醇脂质体与普通紫杉醇制剂分别联合卡铂治疗卵巢癌的有效性和安全性。方法: 计算机检索中国知识资源总库（CNKI）、中国生物医学文献数据库（CBM）、中文科技期刊数据库（VIP）、中国学术期刊数据库（万方数据）、PubMed、Cochrane Library、Embase 中紫杉醇脂质体联合卡铂与紫杉醇联合卡铂化疗治疗卵巢癌的临床随机对照试验,检索范围均为建库至2017年7月12日。2名研究者根据Cochrane系统评价手册5.1.0,按纳入与排除标准独立进行文献筛选、资料提取、质量评价,并使用RevMan5.3软件Meta分析。 结果:共纳入8篇随机对照试验,共计793例受试者。结果显示,在卵巢癌的治疗中,紫杉醇脂质体联合卡铂与紫杉醇联合卡铂比较,客观缓解率有统计学意义（P=0.02）。在不良反应方面,紫杉醇脂质体联合卡铂与紫杉醇联合卡铂比较：血小板减少（P=0.02）、恶心呕吐（P＜0.000 01）、肌肉关节痛（P＜0.000 01）、皮疹（P＜0.000 01）、呼吸困难（P=0.000 8）和面部潮红（P=0.001 0）,差异有统计学意义;而白细胞减少（P=0.13）、血红蛋白减少（P=0.28）、腹泻便秘（P=0.15）、脱发（P=0.62）,差异无统计学意义。结论:紫杉醇脂质体联合卡铂化疗治疗卵巢癌的疗效优于紫杉醇联合卡铂化疗,且能减轻患者不良反应,提高用药有效性和安全性。     

Selective induction of apoptosis in MCF7 cancer-cell by targeted liposomes functionalised with mannose-6-phosphate

Liposomes are versatile platforms to carry anticancer drugs in targeted drug delivery; they can be surface modified by different strategies and, when coupled with targeting ligands, are able to increase cellular internalisation and organelle-specific drug delivery. An interesting strategy of antitumoral therapy could involve the use of lysosomotropic ligand-targeted liposomes loaded with molecules, which can induce lysosomal membrane permeabilization (LMP), leakage of cathepsins into the cytoplasm and subsequent apoptosis. We have previously demonstrated the ability of liposomes functionalised with a mannose-6-phosphate to reach lysosomes; in this research we compare the behaviour of M6P-modified and non-functionalised liposomes in MCF7 tumour cell and in HDF normal cells. With this aim, we first demonstrated by Western blotting the overexpression of mannose-6-phosphate/insulin-like growth factor (M6P/IGF-II) receptor in MCF7. Then, we prepared calcein-loaded liposomes and we revealed the increased uptake of M6P-functionalised liposomes in MCF7 cells respect to HDF cells by flow cytometry analysis. Finally, we loaded functionalised and not functionalised liposomes with N-hexanoyl-d-erythro-sphingosine (C6Cer), able to initiate LMP-induced apoptosis; after having studied the stability of both vesicles in the presence of serum by Dynamic Light Scattering and Spectrophotometric turbidity measurements, we showed that ceramide-loaded M6P-liposomes significantly increased apoptosis in MCF7 with respect to HDF cells.     

Improvement of chemosensitivity and inhibition of migration via targeting tumor epithelial-to-mesenchymal transition cells by ADH-1-modified liposomes

How to overcome drug resistance and prevent tumor metastasis is key to the success of malignant tumor therapy. In this paper, ADH-1 peptide-modified liposomes (A-LP) have been successfully constructed for restoring chemosensitivity and suppressing cancer cell migration. With a particle size of about 90?nm, this functionalized nanocarrier was loaded with fluorescent probe or paclitaxel (PTX). Cellular uptake studies showed that A-LP facilitated the delivery of anticancer drug to tumor cells undergoing EMT. Interestingly, this nanocarrier enhanced chemosensitivity by assessing the cell activity using CCK-8 assay. Further, the results of Wound scratch assay and Transwell migration assay showed the inhibition effect of this nanocarrier on tumor cell migration. Moreover, this nanocarrier exhibited significant tumor-targeting ability and anti-tumor efficacy in vivo. Collectively, A-LP might be a novel targeted drug delivery system to enhance the efficacy of chemotherapy and prevent tumor metastasis.     

Enhanced selective cellular uptake and cytotoxicity of epidermal growth factor-conjugated liposomes containing curcumin on EGFR-overexpressed pancreatic cancer cells

Pancreatic cancer is one of the most malignant cancers with a high mortality rate. Some types of pancreatic cancer cells overexpress epidermal growth factor receptor (EGFR), which is a potential target for anticancer agents. In this study, we examined the effect of epidermal growth factor (EGF)-conjugated liposomes containing curcumin (EGF-LP-Cur) on three different EGFR-expressed human pancreatic cancer cell lines, BxPC-3, Panc-1 and Mia Paca-2. We have demonstrated that it is feasible to prepare liposomal vesicles of EGF-LP-Cur and that it is stable in the liquid vehicle at ambient conditions for three weeks. In addition, the formulation of curcumin had higher cytotoxicity on BxPC-3 than on any other cells. It is also shown that the cellular uptake of curcumin on BxPC-3, which is essential for the cytotoxicity, is associated with EGFR-mediated mechanism of action. In summary, our results have showed that targeting EGFR with EGF-conjugated curcumin liposomes enhanced the antitumor activity of curcumin against human pancreatic cancer cells.