Project Leader

Doctor of Medicine

1990: Graduated from the Faculty of Medicine, The University of Tokyo

1993: Researcher, Growth Factor Research Division, National Cancer Center Research Institute

1997: Division Chief, same institute

2004: Division Chief, Department of Pharmacology, National Cardiovascular Center Research Institute

2018: Director, Peptidomics Research Department, Sasaki Research Institute

2023: Project Leader, Tumor Peptidomics Project, Tochigi Cancer Center Research Institute

Peptidomics is a research field that comprehensively studies peptides with a molecular weight of less than 10 kDa found in cells and tissues. This size range is challenging to analyze using electrophoresis but includes critical peptides such as peptide hormones and antimicrobial peptides, which function as intercellular regulators. Despite advancements in mass spectrometry, this molecular weight range remains poorly understood.

 

Our project aims to elucidate the processing sites of secreted and membrane proteins by studying this domain. Protein processing involves the cleavage of proteins at specific sites by specific enzymes, differing from simple degradative cleavage. Processing can yield biologically active molecules from within proteins or produce soluble receptors capable of capturing ligands. The location of these processing events is influenced by not only the amino acid sequence but also modifications like glycosylation, limiting computational predictions. Thus, identifying these sites requires experimental analysis of actual sequences.

 

Identified processing sites provide valuable insights for discovering novel targets for diagnosis and therapy. To date, we have identified seven novel human bioactive peptides, marking the first global application of mass spectrometry in peptide discovery. Our research focuses on identifying cleavage sites of secreted and membrane proteins expressed in cancer cells to develop diagnostic and therapeutic strategies for cancer.