In this report milk-derived exosomes have been investigated for oral delivery of the chemotherapeutic drug paclitaxel (PAC) as an alternative to conventional i.v. therapy for improved efficacy and reduced toxicity. PAC-loaded exosomes (ExoPAC) were found to have a particle size of ~108 nm, a narrow particle size distribution (PDI ~0.190), zeta potential (~ -7 mV) and a practical loading efficiency of ~8%. Exosomes and ExoPAC exhibited excellent stability in the presence of simulated-gastrointestinal fluids, and during the storage at -80 °C. A sustained release of PAC was also observed up to 48 h in vitro using PBS (pH 6.8). Importantly, ExoPAC delivered orally showed significant tumor growth inhibition (60%; P<0.001) against human lung tumor xenografts in nude mice. Treatment with i.p. PAC at the same dose as ExoPAC, however, showed modest but statistically insignificant inhibition (31%). Moreover, ExoPAC demonstrated remarkably lower systemic and immunogenic toxicities as compared to i.v. PAC.
Milk-derived exosomes for oral delivery of cancer drugs
Agrawal AK, Aqil F, Jeyabalan J, Spencer WA, Beck J, Gachuki BW, Alhakeem SS, Oben K, Munagala R, Bondada S, Gupta RC. (2017) Milk-derived exosomes for oral delivery of paclitaxel. Nanomedicine [Epub ahead of print]. [abstract]