Immune gene therapy as a neoadjuvant to surgical excision to control metastatic cancers

We investigated if the range of efficacy of a gene-based immunotherapy of solid tumours against systemic disease could be extended when used as a neoadjuvant to surgery. Hundred percent mice whose subcutaneous tumours were surgically removed 4 days post-electroporation with GM-CSF and B7-1 plasmid were systemically resistance to tumour rechallenge. In mice bearing both subcutaneous and hepatic tumours, neoadjuvant treatment of the primary tumour resulted in significant reduction in, or elimination of, hepatic tumour growth, with a significant increase in survival, indicating that control of the primary tumour by immunotherapy was not a prerequisite for containment of systemic disease.