Abstract
Current chemotherapeutic agents against esophageal cancer (EC) are suboptimal. To improve treatment efficacy, a nanoplatform based on ATP-responsive drug release was developed for EC therapy. First, the chemotherapeutic agent epirubicin (EPI) was inserted into an ATP aptamer (Ap) to form double-stranded DNA ('DNA duplex'). Subsequently, polyethyleneimine (PEI) was employed to condense the EPI-loaded duplex to construct the final nanoplatform (PEI-Ap-EPI). Following internalization by cancer cells, the EPI-loaded DNA duplex could open and release EPI in an intracellular ATP-rich environment. An in vitro drug-release assay demonstrated that ~50% of EPI was released from PEI-Ap-EPI in an ATP-rich condition. However, only 15% of EPI was released in the presence of a low concentration of ATP. In vitro cytotoxicity and apoptosis assays demonstrated that PEI-Ap-EPI could enhance EPI efficiency against EC cells markedly compared with those in the control group. Therefore, this facile PEI-Ap-EPI nanoplatform may be a promising strategy to improve the efficacy of EPI treatment in EC.