Hsp-based tumor vaccines: state-of-the-art and future directions

Hsp-based tumor vaccines, autologous tumor-derived Hsp-peptide complexes, have been applied to cancer immunotherapy for the treatment of cancer patients with a variety of advanced malignancies. Data from clinical trials, including those from phase III, have so far demonstrated that the immunization strategy can induce significant tumor-specific immune responses. Some improved clinical outcomes have also been observed but the clinical utility of this strategy awaits further investigations. In addition, preclinical studies have been conducted to design a variety of novel Hsp-based tumor vaccines with improved therapeutic potentials. These approaches include development of Hsp fusion proteins and genetic vaccines using plasmid DNA and adenoviruses. Successful cancer immunotherapy with Hsp-based tumor vaccines will depend on the results obtained from both clinical trials and preclinical studies.