Overcoming technical challenges in the development of cancer vaccines.

Cancer vaccines have been developed using a wide range of technologies, yielding agents ranging from nonspecific immunostimulants through to highly technical peptide- and DNA-based candidates. There are many technical challenges involved in even the most basic decisions in vaccine development, such as the choice of antigen, formulation, adjuvant, route of delivery and schedule. However, as discussed in this feature review, the tumor itself may pose the greatest technical challenge, particularly with regard to escaping the immune response. Strategies to overcome this challenge are discussed.