Recently, several therapeutic applications for TAT-mediated cellular internalization have been developed, including the transport of an inhibitor for human papillomavirus type 16 [44] and for the apoptosis-promoting caspase-3 protein used in HIV-therapy [45], the extension of the cytotoxic activity of herpes simplex virus-1 thymidine kinase for cancer therapy [46], dendritic cell-based immunotherapy [47] and enhancement of viral-mediated gene delivery, [48] to name just a few. This evidence concerns the gene CASP3 and cancer.