New strategies to improve the efficacy of colorectal cancer vaccines: from bench to bedside

By exploiting a naturally occurring defense system, anticancer vaccination embodies an ideal non-toxic treatment capable of evoking tumor-specific immune responses that can ultimately recognize and kill colorectal cancer (CRC) cells. Despite the enormous theoretical potential of active specific immunotherapy, no vaccination regimen has achieved sufficient therapeutic efficacy necessary for clinical implementation. Nevertheless, several immunological advances have opened new avenues of research to decipher the biological code governing tumor immune responsiveness, and this is leading to the design of potentially more effective immunotherapeutic protocols. This review briefly summarizes the principles behind anti-CRC vaccination and describes the most promising immunological strategies that have been developed, which are expected to renew interest in this molecularly targeted anticancer approach.