Due to their dynamic nature and excellent stimuli-responsiveness resulting from noncovalent driving forces, artificial molecular machines (AMMs) show great promise in cancer theranostics. In this Perspective, we introduce the potential applications of AMMs in controlled drug delivery, bioorthogonal catalysis, imaging, and cell membrane permeabilization, with the goal of enhancing cancer diagnosis and therapy. We expect this preliminary discussion will garner multidisciplinary interest from scientists to advance AMMs and to expand their future clinical applications.
Eudragit® E 100 (EE100) was used to improve the transfection efficiency of polyethylenimine (PEI).Mobility of PEI-DNA complexes with and without EE100 were visualized by agarose gel electrophoresis and their transfection efficiencies were investigated in KB human oral carcinoma cells by flow cytometry. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay was used to determine the viability of transfected cells.Gel electrophoresis illustrated formation of complete complexes at N/P ratios above 5. PEI had the highest transfection efficiency at an N/P ratio of 15, whereas in combination with EE100, the transfection efficiency was highest at an N/P ratio of 7.5. High concentrations of EE100 in combination with PEI were found to reduce cell viability.The results show a synergistic action of EE100 in transfection of DNA at low N/P ratios compared to PEI alone.
Reported procedures on the synthesis of gold nanoshells with smooth surfaces have merely demonstrated efficient control of shell thickness and particle size, yet no branch and nanoporous features on the nanoshell have been implemented to date. Herein, we demonstrate the ability to control the roughness and nanoscale porosity of gold nanoshells by using redox-active polymer poly(vinylphenol)-b-(styrene) nanoparticles as reducing agent and template. The porosity and size of the branches on this branched nanoporous gold nanoshell (BAuNSP) material can be facilely adjusted by control of the reaction speed or the reaction time between the redox-active polymer nanoparticles and gold ions (Au3+). Due to the strong reduction ability of the redox-active polymer, the yield of BAuNSP was virtually 100%. By taking advantage of the sharp branches and nanoporous features, BAuNSP exhibited greatly enhanced physico-optical properties, including photothermal effect, surface-enhanced Raman scattering (SERS), and photoacoustic (PA) signals. The photothermal conversion efficiency can reach as high as 75.5%, which is greater than most gold nanocrystals. Furthermore, the nanoporous nature of the shells allows for effective drug loading and controlled drug release. The thermoresponsive polymer coated on the BAuNSP surface serves as a gate keeper, governing the drug release behavior through photothermal heating. Positron emission tomography imaging demonstrated a high passive tumor accumulation of 64Cu-labeled BAuNSP. The strong SERS signal generated by the SERS-active BAuNSP in vivo, accompanied by enhanced PA signals in the tumor region, provide significant tumor information, including size, morphology, position, and boundaries between tumor and healthy tissues. In vivo tumor therapy experiments demonstrated a highly synergistic chemo-photothermal therapy effect of drug-loaded BAuNSPs, guided by three modes of optical imaging.
Exendin-4 has been clinically exploited for treating type 2 diabetes, but the short circulation half-life and multiple daily injections limit its widespread application with respect to poor patient compliance, low efficacy, and high treatment cost. In this study, a potent long-acting release system based on biomimetic mineralization was constructed for biocompatible and sustained exendin-4 delivery. Similar to natural biomineralization, exendin-4 can be mineralized to form nanosized mineral solids by means of the reaction between acidic amino acid residues and calcium ions in a supersaturated environment with negligible influence on peptide bioactivity. Mineralized exendin-4 particles may be spontaneously absorbed by a living body under physiologically supersaturated conditions, resulting in gradual dissociation and sustained drug release. In such a way, the glucose level of diabetic mice may be effectively controlled for a long period of time by mineralized exendin-4 without obvious side effects. We believe this biomimetic formulation can serve as a promising candidate for future clinical applications for type 2 diabetes therapies.
<p>Supplemental Figure S1. Contribution of NK and T cells to IFN-gamma production. Supplemental Figure S2. MICA expression on monocytes. Supplemental Figure S3. NKG2D Ligand Expression on C1R and C1R-MICA Cell Lines. Supplemental Figure S4. Monocyte MICA expression does not correlate with NK cell IFN-gamma production. Supplemental Figure S5. NKG2D and MICA expression levels prior to and following co-culture.</p>
The development of smart theranostic systems with favourable biocompatibility, high loading efficiency, excellent circulation stability, potent anti-tumour activity, and multimodal diagnostic functionalities is of importance for future clinical application. The premature burst release and poor degradation kinetics indicative of polymer-based nanomedicines remain the major obstacles for clinical translation. Herein we prepare theranostic shell-crosslinked nanoparticles (SCNPs) using a β-cyclodextrin-based polyrotaxane (PDI-PCL-b-PEG-RGD⊃β-CD-NH
Folate receptor (FR) has proven to be a valuable target for chemotherapy using folic acid (FA) conjugates.However, FA-conjugated chemotherapeutics still have low therapeutic efficacy accompanied with side effects, resulting from complications such as short circulation half-life, limited tumor delivery, as well as high kidney accumulation.Herein, we present a novel FA-conjugated paclitaxel (PTX) prodrug which was additionally conjugated with an Evans blue (EB) derivative for albumin binding.The resulting bifunctional prodrug prolonged blood circulation, enhanced tumor accumulation, and consequently improved tumor therapeutic efficacy.Methods: Fmoc-Cys(Trt)-OH was coupled onto PTX at the 7'-OH position for further synthesis of ester prodrug FA-PTX-EB.The targeting ability was investigated using confocal microscopy and flow cytometry.The pharmacokinetics of this bifunctional compound was also studied.Meanwhile, cell viability was evaluated in normal cells and three cancer cell lines by MTT assay.In vivo therapeutic effect was tested on FR-α overexpressing MDA-MB-231 tumor model.Results: Compared with free PTX, the FA-PTX, PTX-EB and FA-PTX-EB prodrugs increased circulation half-life in mice from 2.19 to 3.82, 4.41, and 7.51 h, respectively.Pharmacokinetics studies showed that the FA-PTX-EB delivered more PTX to tumors than FA-PTX and free PTX.In vitro and in vivo studies demonstrated that FA-EB-conjugated PTX induced potent antitumor activity.Conclusion: FA-PTX-EB showed prolonged blood circulation, enhanced drug accumulation in tumors, higher therapeutic index, and lower side effects than either free PTX or monofunctional FA-PTX and EB-PTX.The results support the potential of using EB for the development of long-acting therapeutics.