DOPC‐Detergent Conjugates: Fusogenic Carriers for Improved In Vitro and In Vivo Gene Delivery

Phospholipid‐detergent conjugates are proposed as fusogenic carriers for gene delivery. Eleven compounds are prepared and their properties are investigated. The ability of the conjugates to promote fusion with a negatively charged model membrane is determined. Their DNA delivery efficiency and cytotoxicity are assessed in vitro. Lipoplexes are administered in the mouse lung, and transgene expression Indeterminate inflammatory activity are measured. The results show that conjugation of 1,2‐dioleoyl‐sn‐glycero‐3‐phosphocholine (DOPC) with C₁₂E₄ produces a carrier that can efficiently deliver DNA to cells, with negligible ­associated toxicity. Fusogenicity of the conjugates shows good correlation with in vitro transfection efficiency and crucially depends on the length of the polyether moiety of the detergent. Finally, DOPC‐C₁₂E₄ reveals highly potent for in vivo DNA delivery and favorably compares to GL67A, the current golden standard for gene delivery to the airway, opening the way for further promising developments.

     

药物输送体系构筑中的超分子组装策略

超分子组装提供了药物输送体系设计的新原理。以高效的分子间非共价键作用为驱动力,超分子药物输送体系能够利用结构简单的分子单体获得精确的成分控制,并使得载体结构易于预测,形貌与体积易于调控,有利于实现药物的控制释放。本文首先总结超分子药物输送体系的研究背景,之后重点介绍基于环糊精、杯芳烃、柱芳烃和葫芦脲的主-客体体系的超分子药物输送体系的构建与药物输送功能,然后介绍水溶性的超分子有机框架在药物输送方面的应用,最后提出了超分子药物载体实用化需要克服的若干挑战性问题。     

Conjugates of Cryptophycin and RGD or isoDGR Peptidomimetics for Targeted Drug Delivery

RGD-cryptophycin and isoDGR-cryptophycin conjugates were synthetized by combining peptidomimetic integrin ligands and cryptophycin, a highly potent tubulin-binding antimitotic agent across lysosomally cleavable Val-Ala or uncleavable linkers. The conjugates were able to effectively inhibit binding of biotinylated vitronectin to integrin α_vβ₃, showing a binding affinity in the same range as that of the free ligands. The antiproliferative activity of the novel conjugates was evaluated on human melanoma cells M21 and M21-L with different expression levels of integrin α_vβ₃, showing nanomolar potency of all four compounds against both cell lines. Conjugates containing uncleavable linker show reduced activity compared to the corresponding cleavable conjugates, indicating efficient intracellular drug release in the case of cryptophycin-based SMDCs. However, no significant correlation between the in vitro biological activity of the conjugates and the integrin α_vβ₃ expression level was observed, which is presumably due to a non-integrin-mediated uptake. This reveals the complexity of effective and selective α_vβ₃ integrin-mediated drug delivery.     

Disterolphospholipids: Nonexchangeable Lipids and Their Application to Liposomal Drug Delivery

Extreme makeover of cholesterol : Cholesterol exchange is a major reason for the instability of liposomes in blood. The formation of a covalent hybrid between cholesterol and glycerophosphocholine preserves the bilayer‐stabilizing effect of free cholesterol but prevents its transfer from the bilayer. Thus, disterolphospholipids (e.g. 1 ) are valuable new components for liposome formulation.

     

Synthesis of a dimeric Lewis antigen and the evaluation of the epitope specificity of antibodies elicited in mice

The Lewis(y)-Lewis(x) heptasaccharide, modified by an artificial aminopropyl spacer, was synthesized by an approach that employed two orthogonally protected lactosamine building blocks. A p-(benzoyl)-benzyl glycoside was used as a novel anomeric protecting group, which could be selectively removed at a late stage in the synthesis, thus offering the benefit of enhanced flexibility. The artificial aminopropyl moiety was modified by a thioacetyl group, which allowed an efficient conjugation to keyhole limpet hemocyanin (KLH) that had been activated with electrophilic 3-(bromoacetamido)-propionyl groups. Mice were immunized with the Le(y)Le(x)-BrAc-KLH antigen. Analysis of the sera by ELISA established that a strong helper T-cell immune response was raised against the Le(y)Le(x) saccharide. Further ELISA analysis showed that the titer for monomeric Le(y) tetrasaccharide was tenfold lower whereas recognition of the Le(x) trisaccharide was negligible.     

Arsenene: A Potential Therapeutic Agent for Acute Promyelocytic Leukaemia Cells by Acting on Nuclear Proteins

Arsenene has recently emerged as a promising new two‐dimensional material for biomedical applications because of its excellent optical and electronic properties. Herein, novel 2D arsenene nanosheets were synthesized and shown to be effective against NB4 promyelocytic leukaemia (APL) cells (82 % inhibition) as well as inducing apoptosis while showing no toxicity towards normal cells. The high zeta potential, small size, and the planar structure were crucial to the toxicity of the materials. Label‐free proteomic profiling analysis suggested that arsenene affected nuclear DNA replication, nucleotide excision repair, and pyrimidine metabolism pathways by downregulating the DNA polymerases POLE, POLD1, POLD2, and POLD3. Mass spectrometric studies showed that arsenene bound mainly to nuclear nucleotide acid binding proteins in NB4 cells and further cellular fluorescence studies revealed that the arsenene destroyed the nuclei. In vivo toxicity tests in mice also indicated the physiological biosafety of arsenene.     

Formulation and Characterization of Chitosan-Decorated Multiple Nanoemulsion for Topical Delivery In Vitro and Ex Vivo

In the present study, chitosan-decorated multiple nanoemulsion (MNE) was formulated using a two-step emulsification process. The formulated multiple nanoemuslion was evaluated physiochemically for its size and zeta potential, surface morphology, creaming and cracking, viscosity and pH. A Franz diffusion cell apparatus was used to carry out in vitro drug-release and permeation studies. The formulated nanoemulsion showed uniform droplet size and zeta potential. The pH and viscosity of the formulated emulsion were in the range of and suitable for topical delivery. The drug contents of the simple nanoemulsion (SNE), the chitosan-decorated nanoemulsion (CNE) and the MNE were 71 ± 2%, 82 ± 2% and 90 ± 2%, respectively. The formulated MNE showed controlled release of itraconazole as compared with that of the SNE and CNE. This was attributed to the chitosan decoration as well as to formulating multiple emulsions. The significant permeation and skin drug retention profile of the MNE were attributed to using the surfactants tween 80 and span 20 and the co-surfactant PEG 400. ATR-FTIR analysis confirmed that the MNE mainly affects the lipids and proteins of the skin, particularly the stratum corneum, which results in significantly higher permeation and retention of the drug. It was concluded that the proposed MNE formulation delivers drug to the target site of the skin and can be therapeutically used for various cutaneous fungal infections.     

Three‐Arm,Biotin‐Tagged Carbazole–Dicyanovinyl–Chlorambucil Conjugate: Simultaneous Tumor Targeting,Sensing, and Photoresponsive Anticancer Drug Delivery

The design, synthesis, and in vitro biological studies of a biotin–carbazole–dicyanovinyl–chlorambucil conjugate (Bio‐CBZ‐DCV‐CBL; 6 ) are reported. This conjugate ( 6 ) is a multifunctional single‐molecule appliance composed of a thiol‐sensor DCV functionality, a CBZ‐derived phototrigger as well as fluorescent reporter, and CBL as the anticancer drug, and Bio as the cancer‐targeting ligand. In conjugate 6 , the DCV bond undergoes a thiol–ene click reaction at pH<7 with intracellular thiols, thereby shutting down internal charge transfer between the donor CBZ and acceptor DCV units, resulting in a change of the fluorescence color from green to blue, and thereby, sensing the tumor microenvironment. Subsequent photoirradiation results in release of the anticancer drug CBL in a controlled manner.     

In Vivo Chemoembolization and Magnetic Resonance Imaging of Liver Tumors by Using Iron Oxide Nanoshell/Doxorubicin/Poly(vinyl alcohol) Hybrid Composites

A hybrid composite made up of superparamagnetic iron oxide nanoshells encapsulating the anticancer drug doxorubicin and bound together by poly(vinyl alcohol) was developed. Transcatheter arterial delivery in an in vivo liver tumor model led to embolization of the liver tumor blood vessels. Embolization was followed by disassembly of the composite. The nanoshells were then able to pass through the leaky tumor vasculature into the tumor tissue, thereby leading to slow and sustained release of the drug. As well as being relatively noncytotoxic, the composite was responsive to magnetic resonance imaging, thus making it a potentially useful theranostic agent.     

Duguetia pycnastera Sandwith (Annonaceae) Leaf Essential Oil Inhibits HepG2 Cell Growth In Vitro and In Vivo

Duguetia pycnastera Sandwith (Annonaceae) is a tropical tree that can be found in the Guyanas, Bolivia, Venezuela, and Brazil. In Brazil, it is popularly known as “ata”, “envira”, “envira-preta”, and “envira-surucucu”. In the present work, we investigated the in vitro and in vivo HepG2 cell growth inhibition capacity of D. pycnastera leaf essential oil (EO). The chemical composition of the EO was determined by GC–MS and GC–FID analyses. The alamar blue assay was used to examine the in vitro cytotoxicity of EO in cancer cell lines and non-cancerous cells. In EO-treated HepG2 cells, DNA fragmentation was measured by flow cytometry. The in vivo antitumor activity of the EO was assessed in C.B-17 SCID mice xenografted with HepG2 cells treated with the EO at a dosage of 40 mg/kg. Chemical composition analysis displayed the sesquiterpenes α-gurjunene (26.83%), bicyclogermacrene (24.90%), germacrene D (15.35%), and spathulenol (12.97%) as the main EO constituents. The EO exhibited cytotoxicity, with IC₅₀ values ranging from 3.28 to 39.39 μg/mL in the cancer cell lines SCC4 and CAL27, respectively. The cytotoxic activity of the EO in non-cancerous cells revealed IC₅₀ values of 16.57, 21.28, and >50 μg/mL for MRC-5, PBMC, and BJ cells, respectively. An increase of the fragmented DNA content was observed in EO-treated HepG2 cells. In vivo, EO displayed tumor mass inhibition activity by 47.76%. These findings imply that D. pycnastera leaf EO may have anti-liver cancer properties.     

Spindle‐Like Polypyrrole Hollow Nanocapsules as Multifunctional Platforms for Highly Effective Chemo–Photothermal Combination Therapy of Cancer Cells in Vivo

The monodispersed spindle‐like polypyrrole hollow nanocapsules (PPy HNCs) as the multifunctional platforms for combining chemotherapy with photothermal therapy for cancer cells are reported. Whereas the hollow cavity of nanocapsules can be used to load the anticancer drug (i.e., doxorubicin) for chemotherapy, the PPy shells can convert NIR light into heat for photothermal therapy. The release of the drug from the spindle‐like PPy HNCs is pH‐sensitive and near‐infrared (NIR) light‐enhanced. More importantly, the spindle‐like PPy HNCs can penetrate cells more rapidly and efficiently in comparison with the spherical PPy HNCs. Both in vitro and in vivo experiments demonstrated that the combination of DOX‐loaded spindle‐like PPy HNCs and NIR light provide a highly effective and feasible chemo‐photothermal therapy cancer method with a synergistic effect. Owing to their high photothermal conversion efficiency, large hollow cavity, and good biocompatibility, the spindle‐like PPy HNCs could be used as a promising new cancer drug‐nanocarrier and photothermal agent for localized tumorous chemo‐photothermal therapy.     

A Potent Glucose–Platinum Conjugate Exploits Glucose Transporters and Preferentially Accumulates in Cancer Cells

Three rationally designed glucose–platinum conjugates (Glc–Pts) were synthesized and their biological activities evaluated. The Glc–Pts, 1 – 3 , exhibit high levels of cytotoxicity toward a panel of cancer cells. The subcellular target and cellular uptake mechanism of the Glc–Pts were elucidated. For uptake into cells, Glc–Pt 1 exploits both glucose and organic cation transporters, both widely overexpressed in cancer. Compound 1 preferentially accumulates in and annihilates cancer, compared to normal epithelial, cells in vitro.     

Coordination‐Driven Self‐Assembly and Anticancer Potency Studies of Ruthenium–Cobalt‐Based Heterometallic Rectangles

Three new cobalt–ruthenium heterometallic molecular rectangles, 1 – 3 , were synthesized through the coordination‐driven self‐assembly of a new cobalt sandwich donor, (η⁵‐Cp)Co[C₄‐trans‐Ph₂(4‐Py)₂] (L ; Cp: cyclopentyl; Py: pyridine), and one of three dinuclear precursors, [(p‐cymene)₂Ru₂(OO∩OO)₂Cl₂] [OO∩OO: oxalato ( A₁ ), 5,8‐dioxido‐1,4‐naphthoquinone ( A₂ ), or 6,11‐dioxido‐5,12‐naphthacenedione ( A₃ )]. All of the self‐assembled architectures were isolated in very good yield (92–94 %) and were fully characterized by spectroscopic analysis; the molecular structures of 2 and 3 were determined by single‐crystal X‐ray diffraction analysis. The anticancer activities of bimetallic rectangles 1 – 3 were evaluated with a 3‐[4,5‐dimethylthiazol‐2‐yl]‐2,5‐diphenyltetrazolium bromide (MTT) assay, an autophagy assay, and Western blotting. Rectangles 1 – 3 showed higher cytotoxicity than doxorubicin in AGS human gastric carcinoma cells. In addition, the autophagic activities and apoptotic cell death ratios were increased in AGS cells by treatment with 1 – 3 ; the rectangles induced autophagosome formation by promoting LC3‐I to LC3‐II conversion and apoptotic cell death by increasing caspase‐3/7 activity. Our results suggest that rectangles 1 – 3 induce gastric cancer cell death by modulating autophagy and apoptosis and that they have potential use as agents for the treatment of human gastric cancer.     

Enhanced In Vitro Antitumor Efficacy and Strong Anti‐Cell‐Migration Activity of a Hydroxycamptothecin‐Encapsulated Magnetic Nanovehicle

A 10‐hydroxycamptothecin‐encapsulated magnetic nanovehicle (HEMN) was fabricated by coencapsulating Fe₃O₄ nanoparticles and 10‐hydroxycamptothecin (HCPT) into a micelle core self‐assembled from the amphiphilic copolymer methoxy‐poly(ethylene glycol)–poly(d,l ‐lactide‐co‐glycolide) through a facile dialysis method. A satisfactory drug‐loading content of (9.03±0.67) % and a relatively high encapsulation efficiency of (53.52±6.46) % were achieved. In vitro drug release was performed by membrane dialysis and a pH‐dependent release behavior was observed. In comparison with free HCPT dissolved in dimethylsulfoxide, HEMNs showed a greatly improved in vitro antitumor efficacy against three different human cancer cell lines—HeLa, A549, and HepG2—and lower IC₅₀ values were measured. The mechanism of cell death was investigated, and it was clearly demonstrated that the apoptosis process was triggered. An in vitro wound‐healing assay and a transwell assay indicated that HEMNs exerted much stronger activity in inhibiting HeLa cell migration. The cellular uptake of HEMNs in a desired area can be significantly enhanced by an external magnetic field. These results demonstrate HCPT‐encapsulated magnetic nanovehicles might have important potential in clinical applications for inhibiting tumor metastasis and for targeted drug delivery.