Exosomes: a potential diagnostic and treatment modality in the quest for counteracting cancer

Abstract

Background Exosomes are nanosized bio vesicles formed when multivesicular bodies and the plasma membrane merge and discharge into bodily fluids. They are well recognized for facilitating intercellular communication by transporting numerous biomolecules, including DNA, RNAs, proteins, and lipids, and have been implicated in varied diseases including cancer. Exosomes may be altered to transport a variety of therapeutic payloads, including as short interfering RNAs, antisense oligonucleotides, chemotherapeutic drugs, and immunological modulators, and can be directed to a specific target. Exosomes also possess the potential to act as a diagnostic biomarker in cancer, in addition to their therapeutic potential. Conclusion In this review, the physiological roles played by exosomes were summarized along with their biogenesis process. Different isolation techniques of exosomes including centrifugation-based, size-based, and polymer precipitation-based techniques have also been described in detail with a special focus on cancer therapeutic applications. The review also shed light on techniques of incubation of drugs with exosomes and their characterization methods covering the most advanced techniques. Myriad applications of exosomes in cancer as diagnostic biomarkers, drug delivery carriers, and chemoresistance-related issues have been discussed at length. Furthermore, a brief overview of exosome-based anti-cancer vaccines and a few prominent challenges concerning exosomal delivery have been concluded at the end. Graphical abstract

Insight into the Functional Dynamics and Challenges of Exosomes in Pharmaceutical Innovation and Precision Medicine

“…The techniques for cargo loading into exosomes are categorized into pre- and post-biogenesis methodologies [ 177 , 178 ]. Pre-production strategies encompass methods such as transfection, co-incubation, and electroporation, implemented before the biogenesis of exosomes [ 179 ]. Post-production approaches include freeze–thaw cycles, incubation, sonication, extrusion, and hypotonic dialysis, applied after exosome formation [ 31 , 179 , 180 ].…”

“…Pre-production strategies encompass methods such as transfection, co-incubation, and electroporation, implemented before the biogenesis of exosomes [ 179 ]. Post-production approaches include freeze–thaw cycles, incubation, sonication, extrusion, and hypotonic dialysis, applied after exosome formation [ 31 , 179 , 180 ]. For instance, Kim et al utilized incubation and sonication to incorporate paclitaxel into exosomes derived from RAW 264.7 cells, aiming to counteract multidrug resistance in cancer therapy [ 181 ].…”

Landscape of tumor and immune system cells-derived exosomes in lung cancer: mediators of antitumor immunity regulation

“…Commonly used strategies for exosome isolation are ultracentrifugation, ultrafiltration, size-exclusion chromatography, polymer centrifugation and microfluidics immunoaffinity capture methodology. All of these methods have their advantages and disadvantages; however, there is currently not a robust, reproducible and standardized method that allows obtaining high purity exosomes ( 14 ). Ultracentrifugation-based techniques still remain the gold standard for exosome isolation, despite their limitations ( 15 ).…”

Engineered exosomes for tissue regeneration: from biouptake, functionalization and biosafety to applications

“…55,56 Polyethylene glycol (PEG) is a commonly used medium in polymer precipitation methods, which reduce the solubility of exosomes and promote the formation of exosome aggregates that are isolated by low-speed centrifugation. 57 The method is inexpensive and delivers a high yield. However, the associated purity is relatively low due to co-precipitation of non-exosomal protein polymers.…”