基于生物矿化的纳米载药体系

基于生物矿化的纳米载药体系具有制备简单、良好的生物相容性和控制药物释放的能力、易被修饰且具备多功能性和靶向性等优点,在临床中拥有巨大的应用前景。本文系统阐述了基于生物矿化的纳米载体的构建原理和分类,重点介绍了它们的靶向性策略和刺激响应释放策略,并展望了其在临床治疗中的应用。     

肿瘤靶向性高分子纳米载体研究现状与展望

综述了肿瘤靶向性高分子纳米载体在抗肿瘤药物的靶向性输送和控制释放方面的研究进展,并详细介绍了被动肿瘤靶向性、主动靶向性、生物可降解性、pH敏感性、还原敏感性、酶敏感性和温度敏感性高分子纳米载体的研究现状,展望了该研究领域的发展方向.     

基于肿瘤微环境响应的DNA纳米结构递药系统

DNA分子由于其独特的生物相容性和可编程性,在增强药物靶向性和降低药物毒性方面展现了独特的优势和巨大的潜力。随着人们对肿瘤微环境研究的深入和环境响应性的DNA触发器的研制,近些年已报道了许多基于肿瘤微环境响应的DNA纳米结构递药系统,这些DNA纳米结构递药系统结合了纳米运载工具良好的生物分布和药代动力学特性,以及小型药物载体的快速扩散和渗透特性。通过靶向广泛的肿瘤栖息地而不是肿瘤特异性受体,该策略有可能克服肿瘤异质性问题,并可用于设计诊断和治疗多种实体肿瘤的纳米颗粒。在体内能够稳定地转运,在肿瘤组织独特的微环境刺激下释放药物,能有效地控制药物释放部位和释放速度,极大地降低了肿瘤治疗的毒副作用。本文主要从pH响应型、GSH响应型、ATP响应型、酶响应型、抗原响应型五个方面,综述了基于肿瘤微环境响应的DNA纳米结构递药系统的最新研究进展,分类介绍了这些DNA纳米载体的设计策略和响应释放机制,此外,还重点介绍了该领域面临的前景和挑战。     

铂类抗癌药物的多功能纳米递送体系

以顺铂为代表的小分子铂类抗癌药物是临床应用的一线化疗药物,但其严重的毒副作用和难以克服的耐药性限制了铂类药物的临床应用和研发。运用纳米药物递送技术可以实现药物的靶向递送和可控释放,来提高药物的生物利用度,降低药物的毒副作用以及耐药性,为癌症的治疗带来新的希望。此外,丰富多样的纳米递送体系易于实现药物与具有生物学活性试剂的共运输,从而为各种治疗策略以及诊疗策略的联用提供可能,为最终实现癌症的精准治疗展现广阔前景。本文从靶向递药、药物可控释放、联合治疗、诊疗一体化四个方面对铂类抗癌药物的多功能纳米递送体系在癌症治疗中的最新研究进展进行综述,同时通过列举最新研究成果,展示了新材料、新技术以及新颖设计思想在铂基纳米递送体系中的应用。     

介孔硅纳米储存器在智能药物释放系统的应用

开发新型细胞微环境刺激响应性智能药物控释系统是目前材料学、药理学与临床医学研究的共同热点之一,其目的在于寻求合适的药物载体,提高药物的安全性、有效性及降低药物毒副作用。本文综述了介孔硅功能复合纳米材料在生物医药领域的应用研究进展;通过对其进行特定的化学修饰、生物修饰、物理修饰,不仅能特异性细胞识别靶向,还能针对病变细胞实现药物定点、定时、定量的“生物爆破”释放;这在药物可控释放、靶向癌症治疗、靶向基因递送等领域展示了其广阔的应用前景。同时,本文还系统地分析和总结了各种智能响应性介孔硅纳米储存器的制备方法和响应机制,包括“无机纳米塞-介孔硅”纳米智能控释系统、“有机大分子控制器-介孔硅”智能功能复合型控释系统、“分子开关控制器-介孔硅”自响应性纳米控释系统等,这为设计新型响应性介孔硅纳米储存器系统提供了借鉴与思路。     

基于介孔二氧化硅纳米颗粒的可控释放体系

基于介孔二氧化硅的控制释放体系具有良好的生物相容性、细胞靶向性、精准响应性控制释放和到达目标位点前有效阻止药物释放等功能特性。近年来,基于介孔二氧化硅的可控释放体系已成为众多科研工作者研究的热点。本文讨论了基于介孔二氧化硅纳米颗粒可控释放体系的特点,同时以不同的响应特性为主线,系统分析和总结了各种响应性介孔二氧化硅控释体系的开关及其控制释放机制,包括氧化还原控释系统、光控释系统、pH控释系统及生物分子相关控释系统等一系列基于介孔二氧化硅的控释系统,并对该领域未来的发展方向作了展望。     

功能高分子引发生物矿化实现肿瘤阻断治疗

作为一种不依赖于肿瘤组织渗透的治疗策略，阻断疗法通过阻碍肿瘤与周围微环境之间的物质交换而有效抑制肿瘤的生长和转移。然而，血管阻断、细胞外基质构建等手段存在系统毒性大、肿瘤杀伤不完全、有效持续时间短等问题。受生物体矿化过程的启发，在肿瘤周围构筑生物矿化层成为一种新兴、安全、有效且持久的肿瘤阻断治疗创新模式。基于此，本研究团队首先将阿仑膦酸钠（ALN）键合到1,2-二硬脂酰基-sn-甘油-3-磷酸乙醇胺-N-聚乙二醇-琥珀酰亚胺酯（DSPE-PEG-NHS）的末端，合成了功能高分子DSPE-PEG-ALN。其中，DSPE端可以插入到细胞膜上，另一端的双膦酸可以高效吸附环境中的钙离子等阳离子而引发矿物沉积的连锁反应，在肿瘤周围形成生物矿化层，阻断肿瘤进展。为了进一步提高矿化策略的选择性，我们设计并合成了肿瘤酸度触发的引发生物矿化的聚氨基酸纳米粒子（BINP）。在中性条件下，BINP上的长烷基链组装在纳米粒子的内部，而在肿瘤组织的弱酸性环境中暴露，实现肿瘤细胞膜的特异性插入，原位引发生物矿化，选择性阻断肿瘤进展。原位引发生物矿化功能高分子的设计和应用为肿瘤阻断治疗提供了具有临床应用前景的创新思...     

基于透明质酸的刺激响应纳米给药系统的研究进展

透明质酸(Hyaluronic acid, HA)是一种天然多糖,具有良好的生物相容性和生物降解性,利用 HA 构建的纳米载体自身就具有肿瘤靶向功能,可以作为抗癌药物载体将药物传递到肿瘤细胞内从而实现精准到达病患处。近年来透明质酸在应用于肿瘤靶向给药系统中的关注越来越多,成为了靶向治疗肿瘤的一大研究热点。基于透明质酸的基本特性和肿瘤靶向的生理学基础,在不同的刺激响应下,透明质酸型纳米给药系统能将药物集中释放于肿瘤的微环境内,更好地杀死肿瘤细胞,同时避免其他正常的组织受到药物损害。本文主要综述了透明质酸型纳米药物输送系统在各种刺激响应下释放药物的最新研究进展。     

生物还原敏感可降解聚合物纳米载体的构建与应用

生物可降解聚合物纳米载体具有较长的体内循环时间、能靶向并富集到肿瘤组织、降低毒副作用、增加药物利用率以及在体内可降解等优越性能,已成为实现肿瘤靶向治疗最有前景的载体系统之一。但是,临床试验结果表明,聚合物纳米药物的治疗效果与人们的预期相差甚远,其中一个重要原因是纳米药物在靶点处药物释放少且缓慢。因此,开发智能型纳米载体使其在到达靶点后即迅速释放包裹的药物成为近年的研究热点。肿瘤组织,尤其是肿瘤细胞内的谷胱甘肽(glutathione,GSH)浓度较高(2~10mM),大约是体液和细胞外基质的100~1000倍(2~10μM)。基于肿瘤独特的还原势能,人们构建了各种不同类型的还原敏感聚合物纳米载体,实现抗癌药物在肿瘤组织和肿瘤细胞内的快速高效释放。生物还原敏感聚合物纳米载体具有以下特点:(1)在生理条件下稳定;(2)对肿瘤细胞内还原环境响应快,触发药物快速释放;(3)无需任何外在刺激装置,简单方便。本文将结合我们课题组的工作介绍各种还原敏感可降解聚合物纳米载体的构建和应用,主要包括还原敏感生物可降解聚合物胶束、囊泡、纳米凝胶等。     

基于大环合成受体的超分子纳米阀门

在特定外界刺激下, 修饰于介孔纳米材料表面的超分子纳米阀门可以有效地控制所包封物质如药物模型分子、 抗癌药物分子和寡核酸等生物分子的靶向释放, 在药物释放、 基因转染及传感等领域有广泛的应用前景. 本文结合本课题组的工作, 综述了国内外在基于大环合成受体的超分子纳米阀门体系的化学构筑及功能等方面的研究进展.     

Endogenous Biomarkers for SLC Transporter-Mediated Drug-Drug Interaction Evaluation

Membrane transporters play an important role in the absorption, distribution, metabolism, and excretion of xenobiotic substrates, as well as endogenous compounds. The evaluation of transporter-mediated drug-drug interactions (DDIs) is an important consideration during the drug development process and can guide the safe use of polypharmacy regimens in clinical practice. In recent years, several endogenous substrates of drug transporters have been identified as potential biomarkers for predicting changes in drug transport function and the potential for DDIs associated with drug candidates in early phases of drug development. These biomarker-driven investigations have been applied in both preclinical and clinical studies and proposed as a predictive strategy that can be supplanted in order to conduct prospective DDIs trials. Here we provide an overview of this rapidly emerging field, with particular emphasis on endogenous biomarkers recently proposed for clinically relevant uptake transporters.     

Dendrimers as Non-Viral Vectors in Gene-Directed Enzyme Prodrug Therapy

Gene-directed enzyme prodrug therapy (GDEPT) has been intensively studied as a promising new strategy of prodrug delivery, with its main advantages being represented by an enhanced efficacy and a reduced off-target toxicity of the active drug. In recent years, numerous therapeutic systems based on GDEPT strategy have entered clinical trials. In order to deliver the desired gene at a specific site of action, this therapeutic approach uses vectors divided in two major categories, viral vectors and non-viral vectors, with the latter being represented by chemical delivery agents. There is considerable interest in the development of non-viral vectors due to their decreased immunogenicity, higher specificity, ease of synthesis and greater flexibility for subsequent modulations. Dendrimers used as delivery vehicles offer many advantages, such as: nanoscale size, precise molecular weight, increased solubility, high load capacity, high bioavailability and low immunogenicity. The aim of the present work was to provide a comprehensive overview of the recent advances regarding the use of dendrimers as non-viral carriers in the GDEPT therapy.     

Natural Product-Based Hybrids as Potential Candidates for the Treatment of Cancer: Focus on Curcumin and Resveratrol

One of the main current strategies for cancer treatment is represented by combination chemotherapy. More recently, this strategy shifted to the “hybrid strategy”, namely the designing of a new molecular entity containing two or more biologically active molecules and having superior features compared with the individual components. Moreover, the term “hybrid” has further extended to innovative drug delivery systems based on biocompatible nanomaterials and able to deliver one or more drugs to specific tissues or cells. At the same time, there is an increased interest in plant-derived polyphenols used as antitumoral drugs. The present review reports the most recent and intriguing research advances in the development of hybrids based on the polyphenols curcumin and resveratrol, which are known to act as multifunctional agents. We focused on two issues that are particularly interesting for the innovative chemical strategy involved in their development. On one hand, the pharmacophoric groups of these compounds have been used for the synthesis of new hybrid molecules. On the other hand, these polyphenols have been introduced into hybrid nanomaterials based on gold nanoparticles, which have many potential applications for both drug delivery and theranostics in chemotherapy.     

Advances in Biomimetic Nanoparticles for Targeted Cancer Therapy and Diagnosis

Biomimetic nanoparticles have recently emerged as a novel drug delivery platform to improve drug biocompatibility and specificity at the desired disease site, especially the tumour microenvironment. Conventional nanoparticles often encounter rapid clearance by the immune system and have poor drug-targeting effects. The rapid development of nanotechnology provides an opportunity to integrate different types of biomaterials onto the surface of nanoparticles, which enables them to mimic the natural biological features and functions of the cells. This mimicry strategy favours the escape of biomimetic nanoparticles from clearance by the immune system and reduces potential toxic side effects. Despite the rapid development in this field, not much has progressed to the clinical stage. Thus, there is an urgent need to develop biomimetic-based nanomedicine to produce a highly specific and effective drug delivery system, especially for malignant tumours, which can be used for clinical purposes. Here, the recent developments for various types of biomimetic nanoparticles are discussed, along with their applications for cancer imaging and treatments.     

Self-assembly of amphiphilic peptides to construct activatable nanophotosensitizers for theranostic photodynamic therapy

A variety of nano-engineered photosensitizers have been developed for photodynamic therapy (PDT) of cancer diseases. However, traditional nano-engineering methods usually cannot avoid drug leakage and premature release, and have disadvantages such as low drug load and inaccurate release. The self-assembly strategy based on amphiphilic peptides has been considered to be more attractive nano-engineering method. Here we developed novel acid-activatable self-assembled nanophotosensitizers based on an amphiphilic peptide derivative. The peptide derivative was synthesized from a fluorescein molecule with thermally activated delayed fluorescence (TADF). The self-assembled nanophotosensitizers can specifically enter the tumor cells and disassemble inside lysosomes companied with “turn-on” fluorescence and photodynamic therapy effect. Such smart nanophotosensitizers will open new opportunities for cancer theranostics.     

High-throughput, accurate mass liquid chromatography/tandem mass spectrometry on a quadrupole time-of-flight system as a 'first-line' approach for metabolite identification studies

Throughput for drug metabolite identification studies has been increased significantly by the combined use of accurate mass liquid chromatography/tandem mass spectrometry (LC/MS/MS) data on a quadrupole time-of-flight (QTOF) system and targeted data analysis procedures. Employed in concert, these tools have led to the implementation of a semi-automated high-throughput metabolite identification strategy that has been incorporated successfully into lead optimization efforts in drug discovery. The availability of elemental composition data on precursor and all fragment ions in each spectrum has greatly enhanced confidence in ion structure assignments, while computer-based algorithms for defining sites of biotransformation based upon mass shifts of diagnostic fragment ions have facilitated identification of positions of metabolic transformation in drug candidates. Adoption of this technology as the 'first-line' approach for in vitro metabolite profiling has resulted in the analysis of as many as 21 new chemical entities on one day from diverse structural classes and therapeutic programs.     

A Nanobody‐Conjugated DNA Nanoplatform for Targeted Platinum‐Drug Delivery

The targeted delivery of chemotherapeutic drugs is a major challenge in the clinical treatment of cancer. Herein, we constructed a multifunctional DNA nanoplatform as a versatile carrier of the highly potent platinum‐based DNA intercalator, 56MESS. In our rational design, 56MESS was efficiently loaded into the double‐bundle DNA tetrahedron through intercalation with the DNA duplex. With the integration of a nanobody that both targets and blocks epidermal growth factor receptor (EGFR), the DNA nanocarriers exhibit excellent selectivity for cells with elevated EGFR expression (a common biomarker related to tumor formation) and combined tumor therapy without obvious systemic toxicity. This DNA‐based platinum‐drug delivery system provides a promising strategy for the treatment of tumors.     

Directed Self‐Assembly of DNA Tiles into Complex Nanocages

Tile‐based self‐assembly is a powerful method in DNA nanotechnology and has produced a wide range of well‐defined nanostructures. But the resulting structures are relatively simple. Increasing the structural complexity and the scope of the accessible structures is an outstanding challenge in molecular self‐assembly. A strategy to partially address this problem by introducing flexibility into assembling DNA tiles and employing directing agents to control the self‐assembly process is presented. To demonstrate this strategy, a range of DNA nanocages have been rationally designed and constructed. Many of them can not be assembled otherwise. All of the resulting structures have been thoroughly characterized by gel electrophoresis and cryogenic electron microscopy. This strategy greatly expands the scope of accessible DNA nanostructures and would facilitate technological applications such as nanoguest encapsulation, drug delivery, and nanoparticle organization.     

Synthesis and biological evaluation of a new series of histone deacetylases inhibitors

Histone deacetylases （HDACs） play an important role in tumorigenesis. Inhibition of HDACs is considered as a potent strategy for cancer therapy. Two lead compounds （ja and jb） were found to have activities against HDACs with IC50 at about 15 μmol/L. Then a new series of hydroximic acid derivatives were designed and synthesized based on them. The HDACs activity assay in vitro found that compounds J04 and ,109 are nearly as potent as the positive control drug Zolinza.