Polymer mediated gene delivery was studied and utilized in adult stem cell therapy. The gene expression of human mesenchymal stem cells (MSCs) could be significantly enhanced by polyethylenimine (PEI) mediated gene delivery. The tumor cell growth could be effectively inhibited both in vitro and in vivo by delivering antisense oligonucleotide with non-viral method. Furthermore, gene activated substrate (GAS) prepared in this study could allow localized gene delivery, sustained gene release, high transfection efficiency, low cytotoxicity and high potential for stem cell recruitment.