ANTITUMOR EFFECTIVENESS OF ELECTROCHEMOTHERAPY WITH BLEOMYCIN IS INCREASED BY TNF-ALPHA ON SA-1 TUMORS IN MICE

With the aim to increase anti-tumor effectiveness of electrochemothera py, adjuvant immunotherapy with tumor necrosis factor-alpha (TNF-alpha ) was tested on tumors in mice. Increased anti-tumor effectiveness on SA-1 tumors was observed after combining TNF-alpha, injected either in tratumorally or peritumorally, with electrochemotherapy using suboptim al dose of bleomycin (BLM). The increased anti-tumor effectiveness was neither the result of potentiated anti-tumor effectiveness of TNF-alp ha due to exposure of tumors to electric pulses, nor due to interactio n with BLM. Therefore, the effect of adjuvant TNF-alpha treatment migh t be immunomodulatory, augmenting the anti-tumor activity of electroch emotherapy, and possibly adding a systemic component to the localized electrochemotherapy treatment. (C) 1997 Elsevier Science Ireland Ltd.