Engineered exosomes as a natural nanoplatform for cancer targeted delivery of metal-based drugs

An iridium(iii)-based photosensitizer disrupting the mitochondrial respiratory chain induces ferritinophagy-mediated immunogenic cell death

Cancer cells have a strategically optimized metabolism and tumor microenvironment for rapid proliferation and growth. Increasing research efforts have been focused on developing therapeutic agents that specifically target the metabolism of cancer cells. In this work, we prepared 1-methyl-4-phenylpyridinium-functionalized Ir(iii) complexes that selectively localize in the mitochondria and generate singlet oxygen and superoxide anion radicals upon two-photon irradiation. The generation of this oxidative stress leads to the disruption of the mitochondrial respiratory chain and therefore the disturbance of mitochondrial oxidative phosphorylation and glycolysis metabolisms, triggering cell death by combining immunogenic cell death and ferritinophagy. To the best of our knowledge, this latter is reported for the first time in the context of photodynamic therapy (PDT). To provide cancer selectivity, the best compound of this work was encapsulated within exosomes to form tumor-targeted nanoparticles. Treatment of the primary tumor of mice with two-photon irradiation (720 nm) 24 h after injection of the nanoparticles in the tail vein stops the primary tumor progression and almost completely inhibits the growth of distant tumors that were not irradiated. Our compound is a promising photosensitizer that efficiently disrupts the mitochondrial respiratory chain and induces ferritinophagy-mediated long-term immunotherapy.

Nanotherapeutics for prostate cancer treatment: A comprehensive review

Prostate cancer (PCa) is the most prevalent solid organ malignancy and seriously affects male health. The adverse effects of prostate cancer therapeutics can cause secondary damage to patients. Nanotherapeutics, which have special targeting abilities and controlled therapeutic release profiles, may serve as alternative agents for PCa treatment. At present, many nanotherapeutics have been developed to treat PCa and have shown better treatment effects in animals than traditional therapeutics. Although PCa nanotherapeutics are highly attractive, few successful cases have been reported in clinical practice. To help researchers design valuable nanotherapeutics for PCa treatment and avoid useless efforts, herein, we first reviewed the strategies and challenges involved in prostate cancer treatment. Subsequently, we presented a comprehensive review of nanotherapeutics for PCa treatment, including their targeting methods, controlled release strategies, therapeutic approaches and mechanisms. Finally, we proposed the future prospects of nanotherapeutics for PCa treatment.

Engineered extracellular vesicles expressing ICAM-1: A promising targeted delivery system for T cell modifications

BACKGROUND

Extracellular vesicles (EVs) are natural nano-carriers that possess the required crucial features of an ideal biomolecular delivery system. However, using unmodified EVs may have some limitations such as low accumulation in target sites. Studies have established that engineering EVs against different cell surface markers can overcome most of these hurdles.

METHODS

In this study, engineered EVs expressing ICAM-1/LAMP2b fusion protein on their surfaces were produced and isolated. The uptake of isolated targeted and non-targeted EVs was evaluated by imaging and flow cytometry. To assess the ability of targeted EVs to be applied as a safe carrier, pAAVS1-Puro-GFP plasmids were encapsulated into EVs by electroporation.

RESULTS

The HEKT 293 cell line was successfully modified permanently by a lentiviral vector to express ICAM-1 on the surface of the derived EVs. The ELISA and western blot tests established the binding affinity of targeted EVs for recombinant LFA-1 with a remarkable difference from non-targeted EVs. Furthermore, flow cytometry results revealed noteworthy differences in the binding of LFA-1-positive, non-targeted EVs, and targeted EVs to LFA-1-negative cells. Finally, imaging and flow cytometry indicated that newly produced EVs could efficiently interact with T cells and functionally deliver loaded plasmids to them.

CONCLUSION

These LFA-1-targeted EVs were able to interact with T cells as their recipient cells. They can be utilized as an ideal delivery system to transfer various biomolecules to T cells, facilitating immunotherapies or other cell-based treatments.

Encapsulation of Ru(II) Polypyridine Complexes for Tumor-Targeted Anticancer Therapy

Ru(II) polypyridine complexes have attracted much attention as anticancer agents because of their unique photophysical, photochemical, and biological properties. Despite their promising therapeutic profile, the vast majority of compounds are associated with poor water solubility and poor cancer selectivity. Among the different strategies employed to overcome these pharmacological limitations, many research efforts have been devoted to the physical or covalent encapsulation of the Ru(II) polypyridine complexes into nanoparticles. This article highlights recent developments in the design, preparation, and physicochemical properties of Ru(II) polypyridine complex-loaded nanoparticles for their potential application in anticancer therapy.

Bone-Targeting Exosome Mimetics Engineered by Bioorthogonal Surface Functionalization for Bone Tissue Engineering

Extracellular vesicles have received a great interest as safe biocarriers in biomedical engineering. There is a need to develop more efficient delivery strategies to improve localized therapeutic efficacy and minimize off-target adverse effects. Here, exosome mimetics (EMs) are reported for bone targeting involving the introduction of hydroxyapatite-binding moieties through bioorthogonal functionalization. Bone-binding ability of the engineered EMs is verified with hydroxyapatite-coated scaffolds and an ex vivo bone-binding assay. The EM-bound construct provided a biocompatible substrate for cell adhesion, proliferation, and osteogenic differentiation. Particularly, the incorporation of Smoothened agonist (SAG) into EMs greatly increased the osteogenic capacity through the activation of hedgehog signaling. Furthermore, the scaffold integrated with EM/SAG significantly improved in vivo reossification. Lastly, biodistribution studies confirmed the accumulation of systemically administered EMs in bone tissue. This facile engineering strategy could be a versatile tool to promote bone regeneration, offering a promising nanomedicine approach to the sophisticated treatment of bone diseases.

Engineered exosomes as a photosensitizer delivery platform for cancer photodynamic therapy

Photodynamic therapy (PDT), a non/minimally invasive cancer treatment method, has the advantages of low side effects, high selectivity, and low drug resistance. It is currently a popular cancer treatment method. However, the shortcomings of photosensitizers such as poor photostability, poor water solubility, and short half-life in vivo when used alone, the development of photosensitizer nano-delivery platforms have always been a research hotspot. In the human body, various types of cells generally release exosomes, the bilayer extracellular vesicles. Compared with traditional materials, exosomes are currently an ideal drug delivery platform due to their homology, low immunogenicity, easy modification, high biocompatibility, and natural carrying capacity. Therefore, in this concept, we focus on the research status and prospects of engineered exosome-based photosensitizer nano-delivery platforms in cancer PDT.