This review highlights the current strategies being employed rewards gene t
herapy of cancer. Conceptually, the most simple diseases to treat with gene
therapy would be menogenic inherited diseases, such as hemophilia. However
, the vast majority of current gene therapy trials are for treatment of can
cer patients, due to the recognition of gene alterations in cancer and the
critical need for improvement of cancer therapy. Gene-based therapies for c
ancer in clinical trials include strategies that involve immune-therapy, in
duction of drug sensitivity in tumor cells or resistance to chemotherapy of
critical host tissues, and compensation for oncosuppressor loss or ablatio
n of oncogenes. Two broad approaches have been used to deliver DNA to cells
, a series of viral vectors and the use of plasmid DNA vectors, which have
different advantages with regard to efficiency of gene transfer, ease of pr
oduction and safety.
Examined objectively, many of the first studies in cancer gene therapy clin
ical trials have provided information of critical importance for the design
of more efficient second-generation protocols. Gene therapy represents one
of the most important developments in oncology, however, before this call
be realized as standard treatment the technical problems of gene delivery a
nd safety must be overcome. Here we focus on methods and strategies used to
achieve cancer gene therapy and the current clinical trials.