[IL-2 gene therapy in ENT carcinomas]

Suppressed cellular immunity is common in patients with squamous cell carcinoma of the head and neck (HNSCC). It was demonstrated in previous studies that administration of interleukin 2 (IL-2) results in enhanced antitumoral immunity in vitro as well as in vivo. Since the serum half-life of IL-2 is relatively short, repeated applications are necessary to achieve therapeutically effective serum concentrations, but this strategy might cause severe side effects. Therefore, methods that provide high local cytokine levels over a prolonged period of time without the need for repeated injections are desirable. Gene therapy as an innovative treatment approach using tumor cells stably transduced to produce IL-2 might meet these criteria. In vitro manipulated tumor cells, if readministered in the vicinity of non-manipulated tumor cells, may enhance a specific anti-tumor response in vivo without systemic side effects. The present manuscript reviews the current literature dealing with IL-2-protein and -gene therapy with special emphasis on head and neck cancer. Our own in vitro results with IL-2 gene therapy in conjunction with published data from other authors argue in favour of an in vivo approach for this therapeutic strategy that is currently in progress in our department.