The article “Engineering of extracellular vesicles as drug delivery vehicles” (doi: 10.21037/sci.2017.08.07) published in Stem Cell Investigation in September 2017 needs to be retracted as part of Figure 1 was adapted from some other publication and the authors did not obtain the copyright permission. I sincerely apologize for the oversight.
All authors agree to the retraction of the paper.
Cite this article as: Kim SM, Kim HS. Retraction: Engineering of extracellular vesicles as drug delivery vehicles. Stem Cell Investig 2018;5:15.