A New Approach for Loading Anticancer Drugs Into Mesenchymal Stem Cell-Derived Exosome Mimetics for Cancer Therapy.

Senthilkumar Kalimuthu,Ramya Lakshmi Rajendran,Byeong-Cheol Ahn,Ho Won Lee,Se Hwan Baek,Jaetae Lee,Shin Young Jeong,Sang-Woo Lee,Prakash Gangadaran,Liya Zhu,Arunnehru Gopal,Ji Min Oh

doi:10.3389/fphar.2018.01116

Senthilkumar Kalimuthu, Ramya Lakshmi Rajendran + Show 10 more

Open Access

https://doi.org/10.3389/fphar.2018.01116

Copy DOI

Abstract

Exosomes derived from mesenchymal stem cells (MSCs) have been evaluated for their potential to be used as drug delivery vehicles. Synthetically personalized exosome mimetics (EMs) could be the alternative vesicles for drug delivery. In this study, we aimed to isolate EMs from human MSCs. Cells were mixed with paclitaxel (PTX) and PTX-loaded EMs (PTX-MSC-EMs) were isolated and evaluated for their anticancer effects against breast cancer. EMs were isolated from human bone marrow-derived MSCs. MSCs (4 × 106 cells/mL) were mixed with or without PTX at different concentrations in phosphate-buffered saline (PBS) and serially extruded through 10-, 5-, and 1-μm polycarbonate membrane filters using a mini-extruder. MSCs were centrifuged to remove debris and the supernatant was filtered through a 0.22-μm filter, followed by ultracentrifugation to isolate EMs and drug-loaded EMs. EMs without encapsulated drug (MSC-EMs) and those with encapsulated PTX (PTX-MSC-EMs) were characterized by western blotting, nanoparticle tracking analysis (NTA), and transmission electron microscopy (TEM). The anticancer effects of MSC-EMs and PTX-MSC-EMs were assessed with breast cancer (MDA-MB-231) cells both in vitro and in vivo using optical imaging. EMs were isolated by the extrusion method and ultracentrifugation. The isolated vesicles were positive for membrane markers (ALIX and CD63) and negative for golgi (GM130) and endoplasmic (calnexin) marker proteins. NTA revealed the size of MSC-EM to be around 149 nm, while TEM confirmed its morphology. PTX-MSC-EMs significantly (p < 0.05) decreased the viability of MDA-MB-231 cells in vitro at increasing concentrations of EM. The in vivo tumor growth was significantly inhibited by PTX-MSC-EMs as compared to control and/or MSC-EMs. Thus, MSC-EMs were successfully isolated using simple procedures and drug-loaded MSC-EMs were shown to be therapeutically efficient for the treatment of breast cancer both in vitro and in vivo. MSC-EMs may be used as drug delivery vehicles for breast cancers.

Highlights

Studies have investigated the possible applications of synthetically isolated vesicles from cells, called as exosome-mimetics (EMs), as drug delivery vehicles (Fais et al, 2013; Jang et al, 2013)
mesenchymal stem cells (MSCs) showed more than 95% expression of CD44 but were negative for CD45 (Supplementary Figure S1)
The Fluc activity of MDA-MB-231/effluc cells was measured with IVIS Lumina III imaging system (Perkin-Elmer)

Summary

Introduction

Studies have investigated the possible applications of synthetically isolated vesicles from cells, called as exosome-mimetics (EMs), as drug delivery vehicles (Fais et al, 2013; Jang et al, 2013). Extracellular vesicles (EVs), including exosomes and microvesicles, are lipid membrane-bound vesicles secreted from all types of cells. EVs may serve as feasible DDSs, they have limitations such as low production yield and complicated procedures (Jang et al, 2013; Gangadaran et al, 2018). EMs display characteristics similar to EVs, such as membrane properties of the parent cells (Roth et al, 2008). In comparison with EVs, EMs offer advantages of low cost and high production yield (Jang et al, 2013; Jo et al, 2014)

Objectives

Methods

Results

Discussion

Conclusion