Cancer Sci. 2006 Oct;97(10):970-6.
Personalized peptide vaccines: a new therapeutic modality for cancer.
Itoh K, Yamada A. Department of Immunology, Kurume University School of Medicine, Center of the 21st Century COE Program for Medical Science, Kurume, Fukuoka, Japan.
Therapeutic cancer vaccines have enjoyed little success so far, although
many clinical trials have been conducted. Therefore, the creation of new
protocols capable of inducing an objective response is required. We examined
two of these protocols in the present review. The first is a personalized
protocol to take into account the immunological diversity of cytotoxic T
lymphocyte responses among patients. The second is a combination therapy
designed to adapt to the presence of major histocompatibility complex (MHC)-loss
cancer cells. The objective response rates of our classical (non-personalized)
peptide vaccines were 0%, whereas that of personalized vaccines was 11.1%
in the total advanced cancers and > or = 20% in malignant glioma and
cervical cancers, respectively. A > or = 50% decrease in serum prostate-specific
antigen (PSA) was seen in 8.7% of advanced hormone refractory prostate cancer
patients by personalized vaccination alone, whereas such a decrease was
seen in 54% of patients when the personalized vaccination was combined with
a low dose of estramustine. Based on these experiences, we propose a personalized
peptide vaccine combined with chemotherapy as a new treatment modality for
cancers.