Listeriolysin O enhances cytoplasmic delivery by Her-2 targeting liposomes

To enhance cytoplasmic delivery of liposomal contents to breast cancer cells, the authors have attached the pore-forming protein, listeriolysin O (LLO), to thermosensitive liposomes. The antibody trastuzumab (Herceptin^®) was also conjugated with the outer surface of the liposomes, resulting in highly specific binding and internalization into mammary epithelial cells that overexpress the human epidermal growth factor receptor 2 (Her-2). The liposomes were preloaded with a marker fluorescent dye, and the effect of LLO on the distribution of dye within the cells was monitored using fluorescence microscopy. Owing to the thermosensitive nature of the liposomes, hyperthermia at 42°C triggered the release of the encapsulated fluorescent calcein from the endocytosed liposomes into the interior of the endosomes. LLO, when conjugated to these liposomes, subsequently formed pores in the endosomal membrane, allowing calcein to flow out of the endosomal compartment into the cytoplasm. Her-2–targeted liposomes bearing LLO delivered a 22-fold greater concentration of calcein to mammary epithelial cells that overexpress Her-2 compared to cells with normal Her-2 expression. Thus, the addition of LLO to preformed liposomes offers a method for significantly enhancing delivery of liposomal contents to the cytoplasm of targeted cells.     

靶向递药系统长循环脂质体的研究进展

长循环脂质体作为一种新型的纳米载药系统,因其能实现血液中长滞留、高浓度靶向富集于病灶部位,在肿瘤的治疗中显示了独特的优势。通过查阅国内外相关文献并进行归纳总结,现就长循环脂质体及其制备方法、质量评价、药动学及药效学等进行综述。     

Perspectives of HER2-targeting in gastric and esophageal cancer

Introduction: The blockade of HER2 signaling has significantly improved the outlook for esophagogastric cancer patients. However, targeting HER2 still remains challenging due to complex biology of this receptor in gastric and esophageal cancers.

Areas covered: Here, we review complex HER2 biology, current methods of HER2 testing and tumor heterogeneity of gastroesophageal cancer. Ongoing and completed clinical research data are discussed.

Expert opinion: HER2 overexpression is a validated target in gastroesophageal cancer, with therapeutic implications resulting in prolonged survival when inhibited in the front-line setting. With standardized HER2 testing in gastro-esophageal cancer, the ongoing trials are testing newer agents and combinations including combination of anti-HER2 antibodies with immunotherapy. Clonal heterogeneity and emergence of resistance will challenge our approach to treating these patients beyond the frontline settings.     

Targeted thermosensitive liposomes: an attractive novel approach for increased drug delivery to solid tumors

Introduction: Currently available chemotherapy is hampered by a lack in tumor specificity and resulting toxicity. Small and long-circulating liposomes can preferentially deliver chemotherapeutic drugs to tumors upon extravasation from tumor vasculature. Although clinically used liposomal formulations demonstrated significant reduction in toxicity, enhancement of therapeutic activity has not fully met expectations.

Areas covered: Low drug bioavailability from liposomal formulations and limited tumor accumulation remain major challenges to further improve therapeutic activity of liposomal chemotherapy. The aim of this review is to highlight strategies addressing these challenges. A first strategy uses hyperthermia and thermosensitive liposomes to improve tumor accumulation and trigger liposomal drug bioavailability. Image-guidance can aid online monitoring of heat and drug delivery and further personalize the treatment. A second strategy involves tumor-specific targeting to enhance drug delivery specificity and drug internalization. In addition, we review the potential of combinations of the two in one targeted thermosensitive-triggered drug delivery system.

Expert opinion: Heat-triggered drug delivery using thermosensitive liposomes as well as the use of tumor vasculature or tumor cell-targeted liposomes are both promising strategies to improve liposomal chemotherapy. Preclinical evidence has been encouraging and both strategies are currently undergoing clinical evaluation. A combination of both strategies rendering targeted thermosensitive liposomes (TTSL) may appear as a new and attractive approach promoting tumor drug delivery.     

新型靶向HER2的抗体偶联药物:trastuzumab deruxtecan

trastuzumab deruxtecan(DS-8201a)是新型靶向人表皮生长因子受体2(HER2)的抗体偶联药物,于2019年12月20日获美国食品和药物管理局加速批准上市,用于治疗有转移性疾病且已接受过2种及以上抗HER2药物治疗方案的HER2阳性、不可切除或转移性乳腺癌成人患者.临床研究表明,DS-8201...     

Injectable delivery system of 2-methoxyestradiol for breast cancer therapy using biodegradable thermosensitive poly(organophosphazene) hydrogel

2-Methoxyestradiol (2-ME) has been reported to have antiangiogenic and antitumor activity. Its biomedical application is limited due to its poor water solubility resulting in its low bioavailability. Poly(organophosphazenes) containing l-isoleucine ethyl ester, ethyl-2-(O-glycyl)lactate, and α-amino-ω-methoxy-poly(ethylene glycol) 550 were synthesized having M_W of 35–38?kDa and polydispersity index of 2.38–2.73. Using a viscometer, the thermosensitivity useful for locally injectable drug delivery was verified. The aqueous polymer solution showed a sol state at a low temperature and transformed to a gel state at body temperature. The polymer solution (10 wt%) enhanced the solubility of 2-ME by about 10⁴ times compared to that of phosphate buffered saline. 2-ME was released from the hydrogel mainly by diffusion, hydrophobic interaction, and surface erosion of the matrix. This release profile could be confirmed through an in vitro release test as a function of polymers and the concentration of 2-ME in hydrogels. By monitoring tumor volume and CD31 immunohistochemical staining in mouse orthotopic breast tumor (MDA-MB-231) model, it was found that the hydrogel containing a relatively low concentration (15?mg/kg) of 2-ME showed the improved antitumor and antiangiogenic activity relative to the original formulation. This research suggests that the developed formulation of poly(organophosphazenes) may have injectable carrier potentials for 2-ME and other lipophilic drugs.     

A new vaginal delivery system of amphotericin B: a dispersion of cationic liposomes in a thermosensitive gel

Amphotericin B (AmB) is used in the treatment of fungal infections; however, its clinical use is limited by its toxic side effects. In this study, AmB-loaded cationic liposome gels were formulated with 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (DOPE), 1,2-dioleoyl-3-trimethylammonium-propane (DOTAP), and cholesterol (CH) at a molar ratio of DOPE:DOTAP:CH?=?4:5:1 in thermosensitive gel composed of poloxamer 407 (P407) and poloxamer 188 (P188). To enhance the solubility of AmB, 6 mol% of distearoyl phosphatidyl ethanolamine–polyethylene glycol was added prior to encapsulation of the drug into liposomes. Scanning electron microscopy was used to observe the AmB encapsulated cationic liposome gels. In vitro release, stability and cytotoxicity of AmB in cationic liposome gels were evaluated. The particle size and zeta potential of AmB-loaded liposomes were in the range of 400–500?nm and 40–60 mV, respectively. The thermosensitive gel at the ratio of P407:P188?=?15:15 (w/w) gelled at 37°C, approximating body temperature. Encapsulation efficiency of AmB was ～50–60%, which was influenced by the ratio of AmB to lipid. Moreover, AmB-loaded cationic liposome gels were more stable and less toxic than free AmB. From these results, cationic liposome gel formulations may be useful for vaginal delivery of AmB.     

含紫杉类方案辅助化疗对Her-2阳性乳腺癌患者生存率的影响

目的观察Her-2/neu过表达的乳腺癌患者对不同辅助化疗方案的敏感性。方法选取2002年5月至2005年8月在我院乳腺中心接受手术且术后辅助化疗的原发性乳腺癌患者Her-2过表达者共134例,分别采用蒽环类或紫杉类方案化疗,中位随访时间38个月,分析她们的临床特征和病理学特征,不同化疗方案对无病生存期的影响。结果Her-2过表达（＋＋、＋＋＋）者134例,占27.7%,采用CAF方案化疗者77例,含紫杉类化疗者57例,采用CAF方案复发转移31.2%（24/77）,无病生存率68.8%,含紫杉类复发率14.0%（8/57）,无病生存率86%,χ^2=5.290,P〈0.05。结论说明含紫杉类方案术后辅助化疗能够提高Her-2/neu过表达的乳腺癌患者的无病生存期。     

Gene delivery to Her-2 + breast cancer cells using a two-component delivery system to achieve specificity

Current liposomal gene delivery systems predominately utilize cationic lipids, which efficiently bind and deliver DNA plasmid, but also result in nonspecific gene expression in lung and liver tissue. To improve specificity, a two-component delivery strategy employing neutral liposomes was used to target breast cancers positive for the human epidermal growth factor receptor 2 (Her-2). The first component consisted of plasmid DNA condensed with cationic polyethylene glycol (PEG) modified polylysine (PL/DNA). The second component was a neutral Her-2 targeting liposome conjugated to the pore-forming protein, Listeriolysin O (LLO). Independently, PL/DNA delivery resulted in low expression of plasmid DNA. However, when PL/DNA and LLO/liposomes co-localized within an endosome, LLO disrupted endosome integrity, leading to cytoplasmic delivery and expression of the plasmid. When used to deliver a plasmid encoding the luciferase gene, this two-component system resulted in gene expression that was 268-fold greater in Her-2 positive cells than in Her-2 negative cells.From the Clinical EditorIn this paper a novel two-component gene delivery method is presented using PL/DNA and LLO liposomes, demonstrating strongly significant results in a model system.     

曲妥珠单抗治疗HER-2阳性乳腺癌门诊化疗风险评估及费用评价

目的：对Her-2阳性乳腺癌患者使用曲妥珠单抗进行门诊化疗开展前瞻性的风险评估及防范策略制定,优化流程的同时减少用药错误的发生,提高医院管理水平;同时与住院化疗对比,从药物经济学角度为降低患者医疗支出提供参考。方法：运用医疗失效模式与效应分析法（healthcare failure mode and effect analysis,HFMEA）,确立主题,组建项目团队,绘制曲妥珠单抗门诊化疗流程图,对各环节潜在的风险进行风险指数分析,制定并实施改进措施;同时将2018年度使用曲妥珠单抗单药治疗的Her-2（+）乳腺癌患者分成门诊化疗组和住院化疗组,对其住院时间,药物费用、其他费用等进行经济学评价,从而对2种化疗方式进行比较。结果：共发现6个环节17条潜在风险,主要包括余药过期、药品储存、药物剂量、用药信息匹配、输液速度问题等,同时对药物储存、药物配制,以及医、药、护、患各环节进行防范策略的制定并实施;门诊化疗和住院化疗相比,住院时间、总费用及其他（除药品以外）费用都要明显优于住院化疗（P<0.001）。结论：HFMEA可以系统性、前瞻性地降低曲妥珠单抗门诊化疗风险,实现门诊化疗安全、有效、经济、便捷,同时门诊化疗较住院化疗更具经济学效益,以最小的时间经济成本实现目标疗效。     

A clinical perspective on escalating or de-escalating adjuvant therapy in HER2+ breast cancer

Introduction: Patients with early HER2-positive breast cancer (BC) benefit from HER2-targeted systemic therapy. The endorsed standard adjuvant treatment for patients with early HER2-positive breast cancer is chemotherapy plus trastuzumab administered for 1 year.

Areas covered: Several trials have investigated modifications of the standard treatment in terms of de-escalation by either shortening the duration or giving less resource-demanding regimens and in terms of escalation by either adding a second anti-HER2 agent or extending the duration of HER2-targeted treatment for more than 12 months. In this perspective, we would offer a comprehensive view of these trials and discuss their findings.

Expert commentary: At the current state of knowledge, there are still open questions regarding the management of HER2+ BC patients, such as the most adequate duration of trastuzumab therapy, the optimal chemotherapy regimen that should be combined with trastuzumab, and the addition of a second anti-HER2 agent. Growing evidences suggest that some HER2+ BC patients may not need chemotherapy. If these patients could be recognized upfront, optimal response could potentially be reached with HER2-targeted therapy alone.     

曲妥珠单抗联合EOX方案治疗Her-2高表达晚期胃癌患者的临床观察

目的观察曲妥珠单抗联合表阿霉素、奥沙利铂及卡培他滨治疗Her-2高表达晚期胃癌患者的疗效和不良反应。方法采用曲妥珠单抗+EOX方案对21例Her-2高表达的患者化疗4～6周期。曲妥珠单抗首次8mg/kg,后6mg/kg d1;表阿霉素50mg/m2 d1;奥沙利铂100mg/m2 d1;卡培他滨1250mg/m2,2次/d,第1～14d;21d为一周期。结果 21例患者有效率为47.6%。中位总生存期14.2个月。不良反应轻。结论曲妥珠单抗联合EOX方案治疗Her-2高表达晚期胃癌患安全有效,值得临床推广。     

Her-2/neu siRNA表达质粒对前列腺癌裸鼠移植瘤生长的影响

目的 观察Her-2/neu siRNA表达质粒对前列腺癌裸鼠移植瘤生长的影响.方法 40只裸鼠皮下接种人前列腺癌PC-3M细胞,分成4组,每组10只.于形成的肿瘤内分别注射转染试剂FuGene HD与Her-2/neu siRNA表达质粒(A组)或无关非同源性序列质粒(B组)的复合物、转染试剂FuGene HD(C组)及生理盐水(D组),每周给药1次,连用4周.首次给药4周后取出肿瘤,测量肿瘤长短径及重量,流式细胞术检测肿瘤细胞周期及细胞凋亡,免疫组化方法 检测肿瘤组织中核增殖抗原(Ki67).结果 A组裸鼠移植瘤体积及重量均明显低于其它三组,凋亡指数显著高于其它三组(P<0.05).A组肿瘤细胞增殖指数显著低于C组(P<0.01).A组肿瘤组织中Ki67阳性的细胞数明显少于其它三组(P<0.01).结论 Her-2/neu siRNA表达质粒对裸鼠前列腺癌移植瘤的生长有抑制作用,并显著促进移植瘤细胞的凋亡.     

A versatile drug delivery system using streptavidin-tagged pegylated liposomes and biotinylated biomaterials

Here we have developed a versatile liposome-mediated drug delivery system (DDS) allowing a strong bridge between the streptavidin-tagged liposome (SAL) and biotin (Bi)-tagged biomaterials which has strong affinity to surface proteins expressed in restricted cell lineages. This DDS was effective and specific for many leukemia cells in vitro and in vivo. When examining 6 human leukemia cell lines using calcein-encapsulated SALs in combination with Bi-granulocyte colony-stimulating factor (G-CSF), Bi-anti-CD33 monoclonal antibody (MAb) or Bi-anti-CD7 MAb, the fluorescent positive rate of each cell line was in almost proportion to degree of G-CSF receptor, CD33 or CD7 expression, respectively. More importantly, the binding ability was shown to be well maintained in a mouse xenograft model. Furthermore the cytosine arabinoside (AraC)-encapsulated SALs could kill the corresponding cells much more effectively in combination with Bi-biomaterials than free AraC, as expected. These findings strongly indicate that our SAL/Bi-biomaterial system could allow various types of medical agents to be delivered reliably and stably to the cells targeted.     

曲妥珠单抗联合多西紫杉醇治疗Her-2阳性乳腺癌的临床研究

目的探析注射用曲妥珠单抗联合多西紫杉醇注射液治疗人类表皮生长因子受体2(Her-2)阳性乳腺癌的临床疗效。方法选取黄石市中心医院(普爱院区)2011年2月—2015年2月收治的乳腺癌患者86例作为研究对象,所有患者按照就诊顺序编号分为对照组和治疗组,每组各43例。对照组静脉滴注多西紫杉醇注射液75 mg/m2,1 h内滴完,间隔21 d重复给药,共给药4次。治疗组在对照组的基础上静脉滴注注射用曲妥珠单抗,将曲妥珠单抗溶于250 mL生理盐水中,首次剂量4 mg/kg,90 min内滴完,之后维持2 mg/kg,1次/周。观察两组的客观有效率、疾病控制率,同时比较治疗前后Her-2表达、细胞凋亡相关因子水平和不良反应发生情况。结果治疗后,对照组、治疗组的客观有效率、疾病控制率分别为60.5%、81.4%,70.0%、88.4%,两组比较差异有统计学意义(P0.05)。治疗后,两组患者Her-2(++)、(+++)比例显著降低,同组治疗前后差异有统计学意义(P0.05);且治疗组指标的降低程度优于对照组,两组比较差异有统计学意义(P0.05)。治疗后两组Caspase-3、DcR3、COX-2水平均显著降低,同组治疗前后差异有统计学意义(P0.05);且治疗组这些观察指标的降低程度优于对照组,两组比较差异有统计学意义(P0.05)。两组不良反应均以胃肠道反应、皮疹、白细胞减少、疲倦、心脏毒性等为主,但各种不良反应发生率的差异无统计学意义。结论注射用曲妥珠单抗联合多西紫杉醇注射液治疗Her-2阳性乳腺癌具有较好的临床疗效,可有效弱化Her-2表达,降低细胞凋亡相关因子水平,安全性佳,值得推广应用。     

曲妥珠单抗辅助化疗治疗HER2阳性乳腺癌有效性和安全性的Meta分析

目的 系统评价曲妥珠单抗辅助化疗治疗HER2阳性乳腺癌的有效性和安全性。方法 计算机检索国内外1996-2013年发表的曲妥珠单抗辅助化疗治疗HER2 阳性乳腺癌的前瞻性随机对照研究,对符合纳入标准的研究以Jadad评分标准进行文献质量评价,并使用Review Manager 5.3进行Meta分析。结果 共纳入4项III 期临床随机对照试验(其中有两项试验为合并分析)。Meta分析结果显示,与单纯化疗相比,曲妥珠单抗联合化疗治疗HER2 阳性乳腺癌可以显著延长患者的无病生存期DFS(HR=0.63,95%CI [0.50,0.81],P<0.001)和总生存期OS(HR=0.69,95%CI [0.56,0.86],P=0.001)。在安全性方面,曲妥珠单抗联合化疗组心脏事件(RR=5.09,95% CI [3.23,8.03],P<0.00001)及充血性心力衰竭(RR=5.32,95% CI [2.28,12.44],P=0.0001)发生率显著高于单纯化疗组,而在心脏事件导致的死亡方面,两组没有显著差异。 结论 曲妥珠单抗联合化疗治疗HER2阳性乳腺癌的疗效显著优于单纯化疗,但心脏事件也显著增加。     

Dual-ligand modified liposomes provide effective local targeted delivery of lung-cancer drug by antibody and tumor lineage-homing cell-penetrating peptide

The abilities of a drug delivery system to target and penetrate tumor masses are key factors in determining the system’s chemotherapeutic efficacy. Here, we explored the utility of an anti-carbonic anhydrase IX (anti-CA IX) antibody and CPP33 dual-ligand modified triptolide-loaded liposomes (dl-TPL-lip) to simultaneously enhance the tumor-specific targeting and increase tumor cell penetration of TPL. In vitro, the dl-TPL-lip increased the cytotoxicity of TPL in CA IX-positive lung cancer cells, which showed tunable size (137.6?±?0.8?nm), high-encapsulation efficiency (86.3?±?2.6%) and sustained release. Dl-TPL-lip significantly improved the ability of liposomes to penetrate 3?D tumor spheroids and exhibited a superior inhibiting effect. Furthermore, pharmacokinetic studies in rats that received TPL liposomal formulations by endotracheal administration showed a reduced concentration of TPL (17.3%–30.6% compared to free TPL) in systemic circulation. After pulmonary administration in orthotopic lung tumor-bearing mice, dl-TPL-lip significantly enhanced TPL anti-cancer efficacy without apparent systemic toxicity. This dual-ligand modified liposomal vehicle presents a potential system for localized and targeted delivery of anti-cancer drugs to improve their efficacy.     

Multiseed liposomal drug delivery system using micelle gradient as driving force to improve amphiphilic drug retention and its anti-tumor efficacy

To improve drug retention in carriers for amphiphilic asulacrine (ASL), a novel active loading method using micelle gradient was developed to fabricate the ASL-loaded multiseed liposomes (ASL-ML). The empty ML were prepared by hydrating a thin film with empty micelles. Then the micelles in liposomal compartment acting as ‘micelle pool’ drove the drug to be loaded after the outer micelles were removed. Some reasoning studies including critical micelle concentration (CMC) determination, influencing factors tests on entrapment efficiency (EE), structure visualization, and drug release were carried out to explore the mechanism of active loading, ASL location, and the structure of ASL-ML. Comparisons were made between pre-loading and active loading method. Finally, the extended drug retention capacity of ML was evaluated through pharmacokinetic, drug tissue irritancy, and in vivo anti-tumor activity studies. Comprehensive results from fluorescent and transmission electron microscope (TEM) observation, encapsulation efficiency (EE) comparison, and release studies demonstrated the formation of ML-shell structure for ASL-ML without inter-carrier fusion. The location of drug mainly in inner micelles as well as the superiority of post-loading to the pre-loading method , in which drug in micelles shifted onto the bilayer membrane was an additional positive of this delivery system. It was observed that the drug amphiphilicity and interaction of micelles with drug were the two prerequisites for this active loading method. The extended retention capacity of ML has been verified through the prolonged half-life, reduced paw-lick responses in rats, and enhanced tumor inhibition in model mice. In conclusion, ASL-ML prepared by active loading method can effectively load drug into micelles with expected structure and improve drug retention.     

Cardiotoxicity of ErbB2-targeted therapies and its impact on drug development,a spotlight on trastuzumab

Introduction: Trastuzumab, a therapeutic monoclonal antibody directed against ErbB2, is often noted as a successful example of targeted therapy. Trastuzumab improved outcomes for many patients with ErbB2-positive breast and gastric cancers, however, cardiac side effects [e.g., left ventricular dysfunction and congestive heart failure (CHF)] were reported in the early phase clinical studies. This finding, subsequently corroborated by multiple clinical studies, raised concerns that the observed cardiotoxicity induced by trastuzumab might adversely impact the clinical development of other therapeutics targeting ErbB family members.

Areas covered: In this review we summarize both basic research and clinical findings regarding trastuzumab-induced cardiotoxicity and assess if there has been an impact of trastuzumab-induced cardiotoxicity on the development of other agents targeting ErbB family members.

Expert opinion: There are a number of scientific gaps that are critically important to address for the continued success of HER2-targeted agents. These include: 1) elucidating the molecular mechanisms contributing to cardiotoxicity; 2) developing relevant preclinical testing systems for predicting cardiotoxicity; 3) developing clinical strategies to identify patients at risk of cardiotoxicity; and 4) enhancing management of clinical symptoms of cardiotoxicity.     

CORM-2-entrapped ultradeformable liposomes ameliorate acute skin inflammation in an ear edema model via effective CO delivery

The short release half-life of carbon monoxide (CO) is a major obstacle to the effective therapeutic use of carbon monoxide-releasing molecule-2 (CORM-2). The potential of CORM-2-entrapped ultradeformable liposomes (CORM-2-UDLs) to enhance the release half-life of CO and alleviate skin inflammation was investigated in the present study. CORM-2-UDLs were prepared by using soy phosphatidylcholine to form lipid bilayers and Tween 80 as an edge activator. The deformability of CORM-2-UDLs was measured and compared with that of conventional liposomes by passing formulations through a filter device at a constant pressure. The release profile of CO from CORM-2-UDLs was evaluated by myoglobin assay. In vitro and in vivo anti-inflammatory effects of CORM-2-UDLs were assessed in lipopolysaccharide-stimulated macrophages and TPA-induced ear edema model, respectively. The deformability of the optimized CORM-2-UDLs was 2.3 times higher than conventional liposomes. CORM-2-UDLs significantly prolonged the release half-life of CO from 30 s in a CORM-2 solution to 21.6 min. CORM-2-UDLs demonstrated in vitro anti-inflammatory activity by decreasing nitrite production and pro-inflammatory cytokine levels. Furthermore, CORM-2-UDLs successfully ameliorated skin inflammation by reducing ear edema, pathological scores, neutrophil accumulation, and inflammatory cytokines expression. The results demonstrate that CORM-2-UDLs could be used as promising therapeutics against acute skin inflammation.