Antitumor effectiveness of electrotransfer of p53 into murine sarcomas alone or combined with electrochemotherapy using cisplatin

The aim of our study was to evaluate feasibility and therapeutic potential of electrotransfer of p53 alone or combined with electrochemotherapy using cisplatin on two murine sarcomas with different p53 status. Antitumor effectiveness of three consecutive electrotransfer of p53 was more effective in wild-type LPB tumor than mutated SA-1 tumors, resulting in 21.4% of tumor cures in LPB tumor and 12.5% in SA-1 tumors. Pretreatment of tumors with electrotransfer of p53 enhanced chemosensitivity of both tumor models treated by electrochemotherapy with cisplatin. After only one application of this treatment combination in LPB tumor model, specific tumor growth delay was prolonged in combined treatment group compared to electrotransfer of p53 or electrochemotherapy with cisplatin alone, whereas in SA-1 tumors this treatment combination resulted in 31.6% of cured animals. Results of our study show that electrotransfer of p53 alone or combined with electrochemotherapy is feasible and effective treatment of tumors. The combination of electrotransfer and electrochemotherapy after only one application resulted in complete regression of tumors.