Clinical evaluation of dendritic cells vaccination for advanced cancer patients at Fukushima Medical University.

Dendritic cells (DCs) are powerful antigen-presenting cells (APCs) that have attracted attention in recent years from the viewpoint of DC vaccine therapy against cancer. However, the existence of a strongly immunosuppressed state in cancer-bearing individuals inhibits DC maturation, which is one of the problems facing anti-cancer DC vaccine therapy. Isolated DCs loaded with tumor antigen ex vivo and administered as a cellular vaccine have been found to induce protective and therapeutic anti-tumor immunity in experimental animals. In clinical trials of DC vaccination for cancer patients, induction of anti-tumor immune responses and tumor regression has been observed. In this study, eighty-one advanced cancer patients unsuccessfully treated by established treatment in individual cases were selected between January 2002 and May 2007 at Fukushima Medical University. The usefulness of DC therapy was investigated by intradermal injection of peptide pulsed DCs for an overall objective response rate of 28.0%. Furthermore, direct injection of immature DCs into tumor extracted an overall objective response rate of 35.7%, and especially 40.0% for advanced pancreatic cancer by using endoscopic ultrasound-guided fine-needle injection technique as a novel approach. These results indicate that DC-based vaccination could be a promising treatment modality for various cancers, however multiple hurdles must be cleared before the development of an affordable DC-based vaccination can be used worldwide.