We screened cell division associated 1 (CDCA1) as an oncogene that is overexpressed on several cancers, including prostate cancer. We also identified a highly immunogenic HLA-A*2402-restricted epitope peptide corresponding to part of the CDCA1 protein. We conducted a phase I clinical trial for patients with castration resistant prostate cancer (CRPC) using a CDCA1 peptide vaccination. Twelve patients having HLA-A*2402 with CRPC after failure of docetaxel chemotherapy were enrolled. They received subcutaneous administration of the CDCA1 peptide as an emulsion with Montanide ISA51VG once a week in a dose-escalation manner (doses of 1.0 or 3.0 mg/body, 6 patients received each dose). The primary endpoint was safety, and the secondary endpoints were the immunological and clinical responses. Vaccination with CDCA1 peptide was well tolerated without any serious adverse events. Peptide-specific cytotoxic T lymphocyte (CTL) responses using ELISPOT assay and dextramer assay were observed in three patients receiving the 1.0 mg dose and five patients receiving the 3.0 mg dose. The median overall survival time was 11.0 months and specific CTL reacting to CDCA1 peptide were recognized in long-surviving patients. CDCA1-derived peptide vaccine treatment was tolerable and might effectively induce peptide-specific CTLs for CRPC patients. This novel peptide vaccine therapy for CRPC appears promising This article is protected by copyright. All rights reserved.
Cancer science. 2017 May 12 [Epub ahead of print]
Wataru Obara, Fuminori Sato, Kazuyoshi Takeda, Renpei Kato, Yoichiro Kato, Mitsugu Kanehira, Ryo Takata, Hiromitsu Mimata, Tamotsu Sugai, Yusuke Nakamura, Tomoaki Fujioka
Department of Urology, Iwate Medical University School of Medicine, Morioka, Japan., Department of Urology, Oita University Faculty of Medicine, Oita, Japan., Division of Cell Biology, Biomedical Research Center, Graduated School of Medicine, Juntendo University, Tokyo, Japan., Department of Molecular Diagnostic Pathology, Iwate Medical University School of Medicine, Morioka, Japan., Department of Medicine and Surgery, University of Chicago, Chicago, IL, USA.