Translational Potential of Surface Engineered Extracellular Vesicles as Theranostic Nanocarriers in Cancer Management: Recent Developments from Bench to Bedside.

Extracellular vesicles (exosomes) are being continuously investigated by researchers as alternative diagnostic and targeted drug delivery nanocarriers for cancer theranostics. Exosomes are nano-extracellular vesicles that contain different biomolecules, including proteins, lipids, and nucleic acids. The natural intercellular communication tendency in recent discoveries to exhibit distinct characteristics in diseased states makes them more interesting for researchers. The molecular composition of exosomes reflects parent cells or their origin and distinguishes the expression of biomarkers. To improve the efficiency of drug-delivery vesicles, the surface of exosomes can be modified using a variety of stimuli-responsive components, including polymers, targeting ligands, enzymes, etc. Cancer physiological and related drug delivery trends in exosomes can challenge the hurdles associated with the cancer microenvironment. The genetic expression of ligands on exosome surfaces adds unique characteristics to tackle the hurdles of the nonexpressive enhanced permeability and retention (EPR) effect in cancers. This Review covers the structural framework, biogenesis, and explored investigational research on exosomes as a theranostic approach in different cancers. The special emphasis on targeted drug delivery and the multistimuli-responsive potential of exosomes in different cancers are discussed briefly, along with recent achievements in the field, such as patents and clinical trials, for further strengthening this platform and developing more effective exosome-based drug delivery systems for cancer management.