Table 1.
Summary of the different approaches in the engineering of EVs for precision cancer therapeutics
| Engineering approach | Examples | Advantages | Disadvantages | References |
|---|---|---|---|---|
| Overexpression of protein in parent cells | Rabies viral glycoprotein, CD63, GLUT4, HSPs, BDNF, CD24, EpCAM, CD3, SMPD2, HIF-1α | Enhanced cargo loading, efficient delivery, relatively simple, biocompatible, stable expression | Low transfection efficiency, contamination of non-transfected EVs, risk of genotoxicity | [51, 52, 57] |
| Antibody/antigen conjugation | CD9 antibody with Alexa-647, mCherry, photoreceptor cryptochrome 2, Nef-E7 fusion protein | Specific and easy to operate, targeted delivery, high therapeutic potential | May impair functionality, low loading efficiency, antigen immunogenicity | [50, 51, 55, 56] |
| Modification of surface proteins | Arg-Gly-Asp (RGD) peptide, Ac4ManNAz, PDGFR | Easy, effective for delivery, fast and scalable production, extended half life | Compromise membrane integrity, may change surface area | [24, 52, 55, 58] |
| Synthetic modification | EMMPRIN, MHC-I and MHC-II | Greater tracking efficiency, high drug loading efficiency | Toxicity, washing required, potential deformation of membrane | [51, 52, 54, 58, 59] |
| Chemical modification | Glypican-1, c(RGDyK) peptides | Enhanced fusion efficiency, better conjugation, stable binding | Toxicity, may impair functionality, harsh chemicals involved | [51, 54, 56, 59] |
| Passive and active loading (sonication, incubation, electroporation) | Paclitaxel, imatinib, siRNA, doxorubicin | Simple, intact membrane, quick and efficient, simple protocol, chemical free | Aggregation, slow passive loading, low efficiency, untargeted release of drugs | [51, 52, 54–57] |