Sirolimus-loaded exosomes as a promising vascular delivery system for the prevention of post-angioplasty restenosis

Extracellular vesicle-based formulation of doxorubicin: drug loading optimization, characterization, and cytotoxicity evaluation in tumor spheroids

Doxorubicin (DOX) is a chemotherapeutic with considerable efficacy, but its application is limited due to cardiotoxicity. Nanoparticles can improve DOX efficacy and prevent its adverse effects. Herein, DOX-loaded extracellular vesicles (DOX-EVs) were prepared using different loading methods including incubation, electroporation, and sonication in different hydration buffers to permeabilize nanostructures or desalinize DOX for improved entrapment. Different protein:drug (µg:µg) ratios of 1:10, 1:5, and 1:2, and incubation parameters were also investigated. The optimal formulation was characterized by western blotting, electron microscopy, Zetasizer, infrared spectroscopy, and release study. The cellular uptake and efficacy were investigated in MCF-7 spheroids via MTS assay, sphere formation assay (SFA), confocal microscopy, and flow cytometry. The percentage of entrapment efficiency (EE) of formulations was improved from 1.0 ± 0.1 to 22.0 ± 1.4 using a protein:drug ratio of 1:2 and sonication in Tween 80 (0.1%w/v) containing buffer. Characterization studies verified the vesicles' identity, spherical morphology, and controlled drug release properties. Cellular studies revealed the accumulation and cytotoxicity of DOX-EVs in the spheroids, and SFA and confocal microscopy confirmed the efficacy and cellular localization. Flow cytometry results revealed a comparable and amplified efficacy for DOX-EV formulations with different cell origins. Overall, the EV formulation of DOX can be applied as a promising alternative with potential advantages.

Encapsulation and assessment of therapeutic cargo in engineered exosomes: a systematic review

Exosomes are nanoscale extracellular vesicles secreted by cells and enclosed by a lipid bilayer membrane containing various biologically active cargoes such as proteins, lipids, and nucleic acids. Engineered exosomes generated through genetic modification of parent cells show promise as drug delivery vehicles, and they have been demonstrated to have great therapeutic potential for treating cancer, cardiovascular, neurological, and immune diseases, but systematic knowledge is lacking regarding optimization of drug loading and assessment of delivery efficacy. This review summarizes current approaches for engineering exosomes and evaluating their drug delivery effects, and current techniques for assessing exosome drug loading and release kinetics, cell targeting, biodistribution, pharmacokinetics, and therapeutic outcomes are critically examined. Additionally, this review synthesizes the latest applications of exosome engineering and drug delivery in clinical translation. The knowledge compiled in this review provides a framework for the rational design and rigorous assessment of exosomes as therapeutics. Continued advancement of robust characterization methods and reporting standards will accelerate the development of exosome engineering technologies and pave the way for clinical studies.

Unveiling Novel Avenues in mTOR-Targeted Therapeutics: Advancements in Glioblastoma Treatment

The mTOR signaling pathway plays a pivotal and intricate role in the pathogenesis of glioblastoma, driving tumorigenesis and proliferation. Mutations or deletions in the PTEN gene constitutively activate the mTOR pathway by expressing growth factors EGF and PDGF, which activate their respective receptor pathways (e.g., EGFR and PDGFR). The convergence of signaling pathways, such as the PI3K-AKT pathway, intensifies the effect of mTOR activity. The inhibition of mTOR has the potential to disrupt diverse oncogenic processes and improve patient outcomes. However, the complexity of the mTOR signaling, off-target effects, cytotoxicity, suboptimal pharmacokinetics, and drug resistance of the mTOR inhibitors pose ongoing challenges in effectively targeting glioblastoma. Identifying innovative treatment strategies to address these challenges is vital for advancing the field of glioblastoma therapeutics. This review discusses the potential targets of mTOR signaling and the strategies of target-specific mTOR inhibitor development, optimized drug delivery system, and the implementation of personalized treatment approaches to mitigate the complications of mTOR inhibitors. The exploration of precise mTOR-targeted therapies ultimately offers elevated therapeutic outcomes and the development of more effective strategies to combat the deadliest form of adult brain cancer and transform the landscape of glioblastoma therapy.