Gene transfer technologies for the gene therapy of cancer.

Gene therapy for cancer relies upon the delivery of a therapeutic gene to a target cell population which may comprise either the tumour cells themselves or specific host effector cells with anti-tumour activity. In addition, gene delivery may be targeted directly to the tumour cells in vivo or towards cells explanted from the patient. The precise requirements of the delivery system depend upon the specific therapeutic strategy being used. In each case, however, delivery must be accurate, efficient and must result in correctly regulated expression of the gene in only the desired cell type. Equally important, the delivery system must be safe for both the patient and the community as a whole. Here, we summarize the types of gene therapy which have been proposed for the treatment of cancer and review how currently available delivery systems are suited to each of these individual strategies.