The current status of gene therapy.

Locoregionally recurrent head and neck squamous cell carcinoma is a logical target for direct delivery of gene therapy approaches. Because the protein p53 plays a role in cell cycle regulation and in apoptosis, p53 gene transfer was initially tested in head and neck cancer patients by injecting the primary or regional tumor with an adenoviral vector possessing wild-type p53. Adenoviral p53 was demonstrated to be safe and well tolerated; furthermore, activity was observed. Several randomized studies of adenoviral p53 are now under way in patients with head and neck squamous cell carcinoma to determine its role as a surgical adjuvant in untreated disease and in combination with DNA-damaging agents.