Chemo-immunotherapy of ovarian cancer in a murine tumour model

Background: As a majority of ovarian cancer patients will ultimately develop recurrent disease, there is an urgent need for alternative or additional approaches in the treatment of this cancer. Materials and Methods: The antitumour effect of i.p. administered cisplatin, liposomal muramyltripeptide phosphatidylethanolamine (L-MTP-PE) and granulocyte-macrophage colony-stimulating factor (GM-CSF) were investigated using an ip. growing murine ovarian tumour. Tumour growth was followed by measuring weight and survival of the mice. Results: An i.p. injection of L-MTP-PE in non-tumour bearing mice resulted in an approximately 10-fold increase in the number of peritoneal cells, which were highly cytotoxic. Nonetheless, treatment of mice inoculated with MOT cells with cisplatin, L-MTP-PE and GM-CSF using different treatment schedules did not result in inhibited tumour growth when compared to treatment with cisplatin alone. Conclusion: Although L-MTP-PE showed art enormous increase in peritoneal cells with high tumour cytotoxic capacity, the immunotherapeutic treatment with GM-CSF and L-MTP-PE, aimed at the recruitment and activation of the peritoneal cell population, failed to result in a significant prolongation of survival.