Prospects for the therapeutic use of anticancer vaccines.
Although a century has passed since initial attempts were made to stimulate the immune system to destroy tumour, the immunotherapy of cancer is still in the early stages. Historically, a variety of specific and nonspecific immunostimulatory strategies have been administered with only modest clinical success. However, recent advances in tumour immunology, most notably the identification of genes encoding for cancer regression antigens, have paved the way for the development of a variety of novel and specific vaccine approaches. These include vaccines based on tumour cells, carbohydrates, peptides and heat-shock proteins, DNA-based vaccination, and the use of recombinant bacteria and viruses to deliver antigens or the DNA coding for them. While several of these approaches have yielded exciting clinical results, a number of immunological and host obstacles to the successful application of cancer vaccines remain. Further research is needed on the optimum choice of antigen, delivery vector, adjuvant and administration regimen.