A proapoptotic peptide for the treatment of solid tumors

We have designed a novel peptide, DPI, which is able to mediate significant induction of apoptosis in solid tumors by local injection. This peptide, c omprised of a protein transduction domain (PTD), PTD-5, fused to an antimic robial peptide, (KLAKLAK)(2), was able to trigger rapid apoptosis in a vari ety of cell lines in vitro, including MCA205 murine fibrosarcomas and human head and neck tumors. Furthermore, direct injection of DPI into day 7 esta blished MCA205 tumors in C57BL/6 mice resulted in the induction of tumor ap optosis and subsequent reduction in tumor volume. These results suggest tha t DPI may be used clinically to treat accessible solid tumors or as an adju vant therapy in conjunction with radiotherapy, standard chemotherapy, immun otherapy, or surgical debulking.