Cancer vaccines: challenges and potential solutions.
Almost a century has passed since immunotherapy of cancer was first attempted using cancer immunogens (vaccines); however, its clinical impact remains modest. Although initial concerns about a lack of human tumor antigens have decreased, prevailing issues include inefficient procedures for immunization and downregulated expression of major histocompatibility complex (MHC) class I molecules in tumor cells. While immunization can be improved, deficient MHC class I expression remains a problem, because it hampers the ability of tumor cells to present antigens for killing by CD8+ T cells. These are the major mediators of tumor destruction, and they have little or no activity against antigen-negative bystander cells. However, there are reasons to be optimistic that therapeutic vaccination against cancer antigens might become a reality at last.
Hellström
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Bristol-Myers Squibb Pharmacetuical Research Institute, Seattle, WA 98121, USA.
Gladstone
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Hellström
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D000818:Animals; D000951:Antigens, Neoplasm / Q000276:immunology*; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D019496:Cancer Vaccines; D015395:Histocompatibility Antigens Class I / Q000276:immunology; D006801:Humans; D009374:Neoplasms, Experimental / Q000517:prevention & control*
D000951:Antigens, Neoplasm; D019496:Cancer Vaccines; D015395:Histocompatibility Antigens Class I