AUTHOR=Oyama Koki , Nakata Kohei , Abe Toshiya , Hirotaka Kento , Fujimori Nao , Kiyotani Kazuma , Iwamoto Chika , Ikenaga Naoki , Morisaki Shinji , Umebayashi Masayo , Tanaka Hiroto , Koya Norihiro , Nakagawa Shinichiro , Tsujimura Kenta , Yoshimura Sachiko , Onishi Hideya , Nakamura Yusuke , Nakamura Masafumi , Morisaki Takashi 

TITLE=Neoantigen peptide-pulsed dendritic cell vaccine therapy after surgical treatment of pancreatic cancer: a retrospective study

JOURNAL=Frontiers in Immunology

VOLUME=Volume 16 - 2025

YEAR=2025

URL=https://www.frontiersin.org/journals/immunology/articles/10.3389/fimmu.2025.1571182

DOI=10.3389/fimmu.2025.1571182

ISSN=1664-3224

ABSTRACT=IntroductionPancreatic cancer shows very poor prognosis and high resistance to conventional standard chemotherapy and immunotherapy; therefore, the development of new breakthrough therapies is highly desirable.MethodWe retrospectively evaluated the safety and efficacy of neoantigen peptide-pulsed dendritic cell (Neo-P DC) vaccine therapy after surgical treatment of pancreatic cancer.ResultThe result showed induction of neoantigen-specific T cells in 13 (81.3%) of the 16 patients who received Neo-P DC vaccines. In survival analysis of the nine patients who received Neo-P DC vaccines after recurrence, longer overall survival was observed in patients with neoantigen-specific T cell induction than those without T cell induction. Notably, only one of the seven patients who received Neo-P DC vaccines as adjuvant setting developed recurrence, and no patient died during median follow-up 61 months after surgery (range, 25-70 months). Furthermore, TCR repertoire analyses were performed in a case treated with Neo-P DC vaccine combined with long and short peptides, and one significantly dominant clone induced by the long peptide was detected among CD4+ T cell populations.DiscussionThe present study suggests the feasibility and efficacy of Neo-P DC vaccine therapy after surgical treatment of pancreatic cancer in both postoperative recurrence cases and adjuvant setting. A case analysis suggests the importance of combination with long peptides targeting CD4+ T cell.