Two for the Price of One: PAMAM-Dendrimers with Mixed Phosphoryl Choline and Oligomeric Poly(Caprolactone) Surfaces

The Application of Nanotechnological Therapeutic Platforms against Gynecological Cancers

Gynecological cancers (GCs), ovarian, cervical, and endometrial/uterine cancers, are often associated with poor outcomes. Despite the development of several therapeutic modalities against GCs, the effectiveness of the current therapeutic approaches is limited due to their side effects, low therapeutic index, short halflife, and resistance to therapy. To overcome these limitations, nano delivery-based approaches have been introduced with the potential of targeted delivery, reduced toxicity, controlled release, and improved bioavailability of various cargos. This review summarizes the application of different nanoplatforms, such as lipid-based, metal- based, and polymeric nanoparticles, to improve the chemo/radio treatments of GC. In the following work, the use of nanoformulated agents to fight GCs has been mentioned in various clinical trials. Although nanosystems have their own challenges, the knowledge highlighted in this article could provide deep insight into translations of NPs approaches to overcome GCs.

Modeling Polyzwitterion-Based Drug Delivery Platforms: A Perspective of the Current State-of-the-Art and Beyond

Drug delivery platforms are anticipated to have biocompatible and bioinert surfaces. PEGylation of drug carriers is the most approved method since it improves water solubility and colloid stability and decreases the drug vehicles’ interactions with blood components. Although this approach extends their biocompatibility, biorecognition mechanisms prevent them from biodistribution and thus efficient drug transfer. Recent studies have shown (poly)zwitterions to be alternatives for PEG with superior biocompatibility. (Poly)zwitterions are super hydrophilic, mainly stimuli-responsive, easy to functionalize and they display an extremely low protein adsorption and long biodistribution time. These unique characteristics make them already promising candidates as drug delivery carriers. Furthermore, since they have highly dense charged groups with opposite signs, (poly)zwitterions are intensely hydrated under physiological conditions. This exceptional hydration potential makes them ideal for the design of therapeutic vehicles with antifouling capability, i.e., preventing undesired sorption of biologics from the human body in the drug delivery vehicle. Therefore, (poly)zwitterionic materials have been broadly applied in stimuli-responsive “intelligent” drug delivery systems as well as tumor-targeting carriers because of their excellent biocompatibility, low cytotoxicity, insignificant immunogenicity, high stability, and long circulation time. To tailor (poly)zwitterionic drug vehicles, an interpretation of the structural and stimuli-responsive behavior of this type of polymer is essential. To this end, a direct study of molecular-level interactions, orientations, configurations, and physicochemical properties of (poly)zwitterions is required, which can be achieved via molecular modeling, which has become an influential tool for discovering new materials and understanding diverse material phenomena. As the essential bridge between science and engineering, molecular simulations enable the fundamental understanding of the encapsulation and release behavior of intelligent drug-loaded (poly)zwitterion nanoparticles and can help us to systematically design their next generations. When combined with experiments, modeling can make quantitative predictions. This perspective article aims to illustrate key recent developments in (poly)zwitterion-based drug delivery systems. We summarize how to use predictive multiscale molecular modeling techniques to successfully boost the development of intelligent multifunctional (poly)zwitterions-based systems.

Functionalization of Nanoparticulate Drug Delivery Systems and Its Influence in Cancer Therapy

Research into the application of nanocarriers in the delivery of cancer-fighting drugs has been a promising research area for decades. On the other hand, their cytotoxic effects on cells, low uptake efficiency, and therapeutic resistance have limited their therapeutic use. However, the urgency of pressing healthcare needs has resulted in the functionalization of nanoparticles' (NPs) physicochemical properties to improve clinical outcomes of new, old, and repurposed drugs. This article reviews recent research on methods for targeting functionalized nanoparticles to the tumor microenvironment (TME). Additionally, the use of relevant engineering techniques for surface functionalization of nanocarriers (liposomes, dendrimers, and mesoporous silica) and their critical roles in overcoming the current limitations in cancer therapy-targeting ligands used for targeted delivery, stimuli strategies, and multifunctional nanoparticles-were all reviewed. The limitations and future perspectives of functionalized nanoparticles were also finally discussed. Using relevant keywords, published scientific literature from all credible sources was retrieved. A quick search of the literature yielded almost 400 publications. The subject matter of this review was addressed adequately using an inclusion/exclusion criterion. The content of this review provides a reasonable basis for further studies to fully exploit the potential of these nanoparticles in cancer therapy.

Nanoparticle-based applications for cervical cancer treatment in drug delivery, gene editing, and therapeutic cancer vaccines

Cervical cancer is a leading cause of gynecological tumor related deaths worldwide. The applications of conventional approaches such as chemoradiotherapy and surgery are restricted due to their side effects and drug resistances. Although immune checkpoint inhibitors (ICIs) have emerged as novel choices, their clinical response rates are rather limited. To date there is a lack of effective treatment regimens for patients with metastatic or recurrent cervical cancer. Recently nanomaterials like liposomes, dendrimers, and polymers are considered as promising delivery carriers with advantages of tumor‐specific administration, reduced toxicity, and improved biocompatibility. Here, we review the applications of nanoparticles in the fields of drug delivery, CRISPR based genome‐editing and therapeutic vaccines in cervical cancer treatment.

This article is categorized under:

Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease

Phosphocholine-Decorated PPI-Dendrimers Mimic Cell Membrane Phosphocholine Clusters and Tune the Innate Immune Activity of C-Reactive Protein

C-reactive protein (CRP) is widely used as biomarkers of infection and inflammation. It has a well-described ability to bind phosphocholine (PC), as well as PC-clusters from compromised and inflamed cell membranes and tissues. The binding of PC-clusters to CRP is of interest as this binding determines subsequent innate immune activity. We investigated PC-decorated dendrimers as mimics for PC-clusters. Five generations of poly(propylene imine) (PPI) dendrimers were modified with PC surface groups via a three-step synthetic sequence obtaining the PC-decorated dendrimers in high purity. The dendrimers were analyzed by NMR and infrared spectroscopy as well as HPLC. We developed immunoassays to show that dendrimer-PC binding to CRP was Ca²⁺-dependent with an apparent overall K_d of 11.9 nM for first generation (G1) PPI-PC, while G2-PPI-PC and G3-PPI-PC had slightly higher affinities, and G4-PPI-PC and G5-PPI-PC had slightly lower affinities. For all PC-dendrimers, the affinity was orders of magnitude higher than the affinity of free phosphocholine (PC), indicating a PC-cluster effect. Next, we investigated the binding of CRP:PPI-PC complexes to complement component C1q. C1q binding to CRP was dependent on the generation of PPI-PC bound to CRP, with second and third generation PPI-PCs leading to the highest affinity. The dendrimer-based approach to PC-cluster mimics and the simple binding assays presented here hold promise as tools to screen PC-compounds for their abilities to tune the innate immune activity of CRP.

Cyclic ethylene phosphates with (CH2)nCOOR and CH2CONMe2 substituents: synthesis and mechanistic insights of diverse reactivity in aryloxy-Mg complex-catalyzed (co)polymerization

Herein we present a comparative study of the reactivity of ethylene phosphates with –O(CH2)nCOOMe (n = 1–3, 5), –CH2COOtBu, –OCHMeCOOMe, and –OCH2CONMe2 substituents in BHT-Mg catalyzed ROP.

Bisubstrate Ether-Linked Uridine-Peptide Conjugates as O-GlcNAc Transferase Inhibitors

The O-linked β-N-acetylglucosamine (O-GlcNAc) transferase (OGT) is a master regulator of installing O-GlcNAc onto serine or threonine residues on a multitude of target proteins. Numerous nuclear and cytosolic proteins of varying functional classes, including translational factors, transcription factors, signaling proteins, and kinases are OGT substrates. Aberrant O-GlcNAcylation of proteins is implicated in signaling in metabolic diseases such as diabetes and cancer. Selective and potent OGT inhibitors are valuable tools to study the role of OGT in modulating a wide range of effects on cellular functions. We report linear bisubstrate ether-linked uridine-peptide conjugates as OGT inhibitors with micromolar affinity. In vitro evaluation of the compounds revealed the importance of donor substrate, linker and acceptor substrate in the rational design of bisubstrate analogue inhibitors. Molecular dynamics simulations shed light on the binding of this novel class of inhibitors and rationalized the effect of amino acid truncation of acceptor peptide on OGT inhibition.

Design, Synthesis, and Characterization of Fully Zwitterionic, Functionalized Dendrimers

Dendrimers are interesting candidates for various applications because of the high level of control over their architecture, the presence of internal cavities, and the possibility for multivalent interactions. More specifically, zwitterionic dendrimers modified with an equal number of oppositely charged groups have found use in in vivo biomedical applications. However, the design and control over the synthesis of these dendrimers remains challenging, in particular with respect to achieving full modification of the dendrimer. In this work, we show the design and subsequent synthesis of dendrimers that are highly charged while having zero net charge, that is zwitterionic dendrimers that are potential candidates for biomedical applications. First, we designed and fully optimized the synthesis of charge-neutral carboxybetaine and sulfobetaine zwitterionic dendrimers. Following their synthesis, the various zwitterionic dendrimers were extensively characterized. In this study, we also report for the first time the use of X-ray photoelectron spectroscopy as an easy-to-use and quantitative tool for the compositional analysis of this type of macromolecules that can complement techniques such as nuclear magnetic resonance and gel permeation chromatography. Finally, we designed and synthesized zwitterionic dendrimers that contain a variable number of alkyne and azide groups that allow straightforward (bio)functionalization via click chemistry.

Surface functionalized dendrimers as controlled-release delivery nanosystems for tumor targeting

Dendrimers are nano-sized and three-dimensional macromolecules with well-defined globular architecture and are widely used in various aspects such as drug and gene delivery owing to multivalent and host-guest entrapment properties. However, dendrimers like other nanomaterials have some disadvantages for example rapid clearance by reticuloendothelial system, toxicity due to interaction of amine terminated group with cell membrane, low transfection efficiency and lack of controlled release behavior, which reduce their therapeutic efficiency. To solve these problems, surface functionalization of dendrimers can be carried out. Surface functionalization not only mitigates this obstacle but also renders excessive specificity to dendrimer to improve efficiency of cancer therapy. Specific properties in cancer cell compared to normal cells such as overexpression of various receptors and difference in biological condition like pH, temperature and redox of tumor environment can be an appropriate strategy to increase site-specific targeting efficiency. Therefore, in this article we focus on numerous functionalization strategies, which are used in the modification of dendrimers through attachment of lipid, amino acid, protein/peptide, aptamer, vitamin, antibody. Moreover, increased biocompatibility, site-specific delivery based on various ligands, enhanced transfection efficiency, sustained and controlled release behavior based on stimuli responsiveness are benefits of functionalized dendrimer which we discuss in this review. Overall, these functionalized dendrimers can open a new horizon in the field of targeted drug and gene delivery.

Model studies of the sequential and simultaneous statistical modification of dendritic functional groups and their implications within complex polymer architecture synthesis

Accurate analysis of model systems by MALDI-TOF has established the diversity of structures formed during post-synthesis functionalisation of complex polymer architectures. NMR studies alone are shown to be highly misleading.