Tumor antigens as surrogate markers and targets for therapy and vaccines.

There are a large number of tumor antigens, which may either be specific to the tumor or inappropriately expressed or processed (tumor-associated antigen, TAA). Over the last few years, hundreds of new TAAs have been identified. Some of these represent good targets for both passive (antibody based) and active (vaccine based) therapies. Antibody treatments targeted on tumor-specific antigens, such as Herceptin and Cetuximab, have been effective in clinical trials and are now licensed. In addition, TAAs act as good surrogate markers for use in both the diagnosis and assessment of treatment in cancer patients.