Group for Innovative Cancer TreatmentDivision of Cancer Immunology

Intrdoduction

Our research aims at clarifying the immune suppressive network in the tumor microenvironment by integrating the study of basic science, genomics, metabolisms, and multi-omics analysis, contributing to the development of novel immunotherapy. We mainly explore regulatory T (Treg) cells, which are essential for tumor development and growth by inhibiting anti-tumor immune responses.

Based on the immune-editing hypothesis, less immunogenic cancer cells such as harboring smaller numbers of neoantigens derived from gene alterations or expressing reduced levels of major histocompatibility complex (MHC) are selected by the immune system. In addition, the immune suppressive tumor microenvironment composed of abundant immune suppressing cells including Treg cells and multiple immune checkpoint molecules is established. Therefore, we develop novel strategies to contorl the immune suppresive tumor microenvironment, particularly Treg cells, leading the immunological balance in the tumor microenvironment to augement anti-tumor immune responses.

Furthermore, while cancer immunotherapy, particularly immune checkpoint blockade, has emerged as a new class of cancer treatment, even at advanced stages of disease, the therapeutic efficacy is currently limited to 15-30% of the treated patients. Therefore, identifying biomarker(s) that can stratify responders from non-responders are urgent problem in the cancer immunology field. We are also addressing the issue from the view of immune suppressive tumor microenvironment, particularly Treg cells.

Education

Post-doctoral fellows and graduate school students are trained in our Division.

Future prospects

Samples from peripheral blood and tumor tissues have been collected more rapidly than expected. In addition to immune assays, we also analyze environmental factors such as microbiota in colon cancers. Base on this, we will comprehensively investigate immune cells such as CD4⁺, CD8⁺ T cells and macrophages, cancer cells and environmental factors to clarify the molecular mechanisms that control immune balances in a tumor microenvironment.