Histidine-Tagged Folate-Targeted Gold Nanoparticles for Enhanced Transgene Expression in Breast Cancer Cells In Vitro

Nanotechnology has emerged as a promising treatment strategy in gene therapy, especially against diseases such as cancer. Gold nanoparticles (AuNPs) are regarded as favorable gene delivery vehicles due to their low toxicity, ease of synthesis and ability to be functionalized. This study aimed to prepare functionalized AuNPs (FAuNPs) and evaluate their folate-targeted and nontargeted pCMV-Luc-DNA delivery in breast cancer cells in vitro. CS was added to induce stability and positive charges to the AuNPs (Au-CS), histidine (Au-CS-His) to enhance endosomal escape and folic acid for folate-receptor targeting (Au-CS-FA-His). The FAuNP:pDNA nanocomplexes possessed favorable sizes (<135 nm) and zeta potentials (<-20 mV), strong compaction efficiency and were capable of pDNA protection against nuclease degradation. These nanocomplexes showed minimal cytotoxicity (>73% cell viability) and enhanced transgene activity. The influence of His was notable in the HER2 overexpressing SKBR3 cells, which produced higher gene expression. Furthermore, the FA-targeted nanocomplexes enhanced receptor-mediated endocytosis, especially in MCF-7 cells, as confirmed by the receptor competition assay. While the role of His may need further optimization, the results achieved suggest that these FAuNPs may be suitable gene delivery vehicles for breast cancer therapeutics.

Pyridinium and indole orientation determines the mitochondrial uncoupling and anti-cancer efficiency of F16

F16 is a mitochondria-targeted, broad-spectrum anticancer agent in the pre-clinic cancer therapy. Here we developed two fluorescent isomers of F16 (o-F16 and m-F16) with entirely different photophysical properties, uncoupling activity, and cytotoxicity by merely modifying the linking orientation of pyridinium and indole units. Individually, o-F16 acted as a strong uncoupler to reduce the mitochondrial respiration efficiency, while m-F16 could hardly uncouple the mitochondrial respiration due to its poor proton dissociation capability. Owing to their intrinsic fluorescence, o-F16 and m-F16 could specifically image mitochondria in the green and red channel, respectively. This work could provide useful information for the development of uncouplers and design of mitochondrial-targeted drugs.

Fabrication of Mesoporous-Silica-Coated Upconverting Nanoparticles with Ultrafast Photosensitizer Loading and 808 nm NIR-Light-Triggering Capability for Photodynamic Therapy

A novel photodynamic therapy nanoplatform based on mesoporous-silica-coated upconverting nanoparticles (UCNP) with electrostatic-driven ultrafast photosensitizer (PS) loading and 808 nm near infrared (NIR)-light-triggering capabilities has been fabricated. By positively charging inner channels of the mesoporous silica shell with amino groups, a quantitative dosage of negatively charged PS, exemplified with Rose Bengal (RB) molecules, can be loaded in 2 min. In addition, the electrostatic-driven technique simultaneously provides the platform with both excellent PS dispersity and leak-proof properties due to the repulsion between the same-charged molecules and the electrostatic attraction between different-charged PS and silica channel walls, respectively. The as-coated silica shell with an ultrathin thickness of 12±2 nm is delicately fabricated to facilitate ultrafast PS loading and efficient energy transfer from UCNP to PS. The outside surface of the silica shell is capped with hydrophilic β-cyclodextrin, which not only enhances the dispersion of resulting nanoparticles in water but also plays a role of "gatekeeper", blocking the pore opening and preventing PS leaking. The in vitro cellular lethality experiment demonstrates that RB molecules can be activated to effectively generate singlet oxygen and kill cancer cells upon 808 nm NIR light irradiation.

Fabrication of a silica/titania hollow nanorod and its electroresponsive activity

In this study, a 1D oriented hollow SiO₂/TiO₂ (HST) rod-like material was successfully fabricated via a sequential combination of sol–gel use, TiO₂ incorporation, and a sonication-mediated etching and redeposition method.

Preparation of hypocrellin B nanocages in self-assembled apoferritin for enhanced intracellular uptake and photodynamic activity

Novel hypocrellin B loaded apoferritin nanoparticles were successfully developed to increase the photosensitizer's solubility, intracellular uptake and photodynamic activity.

Nanocomposite-Based Photodynamic Therapy Strategies for Deep Tumor Treatment

Photodynamic therapy (PDT), as an emerging clinically approved modality, has been used for treatment of various cancer diseases. Conventional PDT strategies are mainly focused on superficial lesions because the wavelength of illumination light of most clinically approved photosensitizers (PSs) is located in the UV/VIS range that possesses limited tissue penetration ability, leading to ineffective therapeutic response for deep-seated tumors. The combination of PDT and nanotechnology is becoming a promising approach to fight against deep tumors. Here, the rapid development of new PDT modalities based on various smartly designed nanocomposites integrating with conventionally used PSs for deep tumor treatments is introduced. Until now many types of multifunctional nanoparticles have been studied, and according to the source of excitation energy they can be classified into three major groups: near infrared (NIR) light excited nanomaterials, X-ray excited scintillating/afterglow nanoparticles, and internal light emission excited nanocarriers. The in vitro and in vivo applications of these newly developed PDT modalities are further summarized here, which highlights their potential use as promising nano-agents for deep tumor therapy.