TAT and central nervous system cancer: The in vitro cytotoxicities of the formulations were evaluated in rat glioma C6 cells wherein CPT-loaded mPEG-PCL-Tat/siRaf-1 complex exhibited a significant increment in the induction of cell death as compared to a combination of mPEG-PCL-Tat/siRaf-1 complex and CPT-loaded mPEG-PCL-Ta.