Expression of Concern: J Transl Med (2014) 12:318 DOI 10.1186/s12967-014-0318-7

The Editor-in-Chief of the Journal of Translational Medicine is issuing an editorial expression of concern to alert readers that concerns have been raised regarding the ethics of this study [1] and the potential association of the risk of teratoma formation with the transplantation of embryonic stem cells. Appropriate editorial action will be taken once this has been fully investigated. The authors disagree with this notice.