Agenda
Day 1
10:00
Opening remark and overview
Takashi Nishimura, Hokkaido University, Institute for Genetic Medicine
Session I: Experimental basic research in cancer immunosurveillance
10:20 - 11:40.
Tsukasa Seya, Hokkaido University, Graduate School of Medicine, Department of Microbiology and Immunology
Molecular mechanism whereby Toll-activating adjuvants induce tumor regression.
Hiroaki Ikeda, Hokkaido University, Institute for Genetic Medicine
Cancer immunoediting: Molecular mechanisms and therapeutic implications
Hiroyoshi Nishikawa, Ludwig Institute for Cancer Research, New York Branch at MSKCC Role of CD4+ CD25+ regulatory T cells in tumor immunity - from mouse models to cancer patients-
Takashi Nishimura, Hokkaido University, Institute for Genetic Medicine Effective strategies for selective activation of type1 immunity essential for inducing tumor-specific CTL in tumor-bearing host
Session II: Basic Research for Tumor Immunity in Human
13:40 - 15:20
Mari Kannagi, Tokyo Medical Dental University, Graduate School
A crossing of infection and tumor immunity against adult T-cell leukemia.
Esteban Celis, Louisiana State University Health Sciences Center, Cancer Immunology/Immunotherapy Program
Development of a Peptide-Based Vaccine for the Treatment of Prostate Cancer.
Rong-fu Wang, Baylor College of Medicine, The Center for Cell and Gene Therapy
Suppression mechanisms and functional control of regulatory T cells in cancer therapy
Yoshiki Akatsuka, Kiyotaka Kuzushima, Toshitada Takahashi, Aichi Cancer Center
Identification of minor histocompatibility antigens involved in graft-versus-leukemia effect and GVHD following allogeneic hematopoietic cell transplantation
Eiichi Sato, Tokyo Medical University
Clinico-pathological significance of tumor infiltrating lymphocytes.
Session III: Cancer vaccine clinical trials
15:40 - 17:00
Eric W. Hoffman, Ludwig Institute for Cancer Research, New York
Cancer vaccine clinical trials
Yutaka Kawakami, Keio University School of Medicine, Institute for Advancer Medical Research
Individualized immunotherapy based on the analysis of human tumor antigens -Intratumoral administration of dendritic cells-
Gerd Ritter, Ludwig Institute for Cancer Research, New York
Development of cancer vaccines: Bridging laboratory and clinical discovery
Sacha Gnjatic, Ludwig Institute for Cancer Research, New York Branch at MSKCC
Clinical trials with NY-ESO-1 protein or DNA: Strategy for immunization and monitoring of antibody and T cell response
Day 2
Session III (continues from August 19): Cancer vaccine clinical trials
9:00 - 11:20
Hiroshi Shiku, Mie University School of Medicine
HER2 protein-based cancer vaccine with a novel antigen delivery system of cholesteryl hydrophobized polysaccharides (CHP).
Eiichi Nakayama, Okayama University Graduate School of Medicine and Dentistry, Department of Immunology
Immunization of patients with tumors expressing NY-ESO-1 antigen with a complex of cholesterol-bearing hydrophobized pullulan and NY-ESO-1 protein.
Masataka Yasukawa, Ehime University School of Medicine
Cellular immunotherapy for leukemia
Jyun Yoshida, Yuichiro Sato, Nagoya University Graduate School of Medicine
New therapeutic strategy against malignant brain tumor utilizing liposome
Hideaki Tahara, University of Tokyo, Institution of Medical Science, Advanced Clinical Research Center
Anti-angiogenic cancer therapy with vaccination using epitope peptides derived from human vascular endothelial growth factor receptor 2 (VEGFR2)
Norimitsu Kadowaki, Kyoto University Graduate School of Medicine
Basic Immunology of human dendritic cells and its application for Cancer Immunotherapy.
11:20
Closing remark
Eric W. Hoffman, Ludwig Institute for Cancer Research, New York
Topics and Scientific Achievements
Discovery of tumor antigen peptides and the demonstration of the existence of cancer immnunosurveillance clearly showed that the immune system can recognize and destroy the arising tumor in host. However, immunotherapy of cancer patients is still difficult because of the immunosuppressive mechanisms in the tumor-bearing host, and we have not achieved the development of efficient cancer vaccine therapies. To overcome this problem, researchers discussed the issues in three sessions. Experimental basic research in cancer immunosurveillance was discussed in session 1. Basic research for tumor immunity in human was discussed in session 2. Cancer vaccine clinical trials were discussed in session3.
In session 1, Ikeda demonstrated and the concept of cancer immunosurveillance. He showed a new finding that type 1 interferon was involved in the immunosurveillance system. The implication of this finding for clinical application was discussed. Seya presented the importance of toll-like receptors and their ligands in innate immunity. The possible role of them in the rejection of tumor was discussed. Nishikawa presented the activation of CD4+ CD25+ regulatory T cells by immunization with SEREX defined self antigens. He also presented the effect of the depletion of regulatory T cells in the PBMC from cancer patients. The role of regulatory T cells in anti-tumor immunity was discussed. Lastly Nishimura demonstrated the importance of the selective activation of type 1 immunity to induce tumor specific CTL in tumor-bearing host. The strategy of clinical trials with tumor antigen protein and CpG was discussed. As a summary of this session, the necessity of the precise understanding of the integrated anti-immune response including the innate and adoptive immunity as well as the mechanisms of immunosuppression in tumor bearing host. It is also pointed out that we need to design the clinical trials on these newest findings and feedback study from these clinical trials.
In session 2, Kannagi reported that the stem-cell transfusion into ATL patients resulted in the induction of Tax specific CTL. The possibility of the immunological therapy targeting tax epitope was discussed. Celis reported the identification of epitope peptides derived from PAMA, TARP, and STEAP for CD8 and CD4 positive T cells. He demonstrated the enhanced anti-tumor immune response in the protocol utilizing a toll-like receptor ligand. Efficacy of the clinical protocol with toll-like receptor ligand was discussed. Wang reported an amazing finding that poly-G, a stimulator of toll-like receptor, can reverse immunosuppression of tumor- patients. The possible effective immunotherapy of cancer patients to overcome the immunosuppressive state of cancer patients by the use of this finding was discussed. Akatsuka reported the induction of CTLs recognizing Minor histocompatibility antigens (mHAgs), BCL1A1 and TMSB4Y. The possible application of mHAgs as targets for the immunotherapy of hematological malignancies was discussed. Sato reported that the number of CD8 positive TIL, CD8/CD4 in TIL, and CD8/Treg in TIL showed prognostic significance in ovarian malignancy. The necessity of the investigation of cellular populations that show prognostic significance in a variety of malignancies was discussed. As a summary of this session, the requirement of the strategy to reverse immunosuppression not only in animal models but also in cancer patients for the efficient eradication of tumor was clearly recognized, and future design of the cancer vaccine therapy was discussed.
In session 3, Hoffman overviewed the cancer vaccine clinical trials in USA especially in LICR. Kawakami reported the basic data of dendritic cells activated by toll-like receptor ligands, and reported the clinical trial with these dendritic cells in Keio University. Ritter pointed out that the existing academic and commercial structures were not well suited to support an efficient and timely transfer of laboratory discoveries into early phase clinical trials. Better structures for translational research such as Cancer Vaccine Collaborative (CVC) was discussed. Gnjatic reported the phase 1 clinical trials with NY-ESO-1 protein or DNA aiming the activation of both CD4 positive and CD8 positive T cells. Both protocol were safe, but sporadic activation of CD8 T cells was observed so far. Shiku reported a phase 1 clinical trial utilizing HER2 protein and a novel antigen delivery system, CHP. The vaccine was safe. Specific CD4 positive and CD8 positive T cell activation with antibody production were observed. Nakayama reported a phase 1 clinical trial with NY-ESO-1 protein with CHP. Vaccine was safe, and antibody production was increased in all 8 patients. Some patients showed specific CD4 positive and CD8 positive T cell activations. Yasukawa demonstrated the induction of WT-1 specific MHC class I restricted or class II restricted T cells, and their cancer therapy experiments in nude mice with these T cells. He reported that they started a phase 1 clinical trial with the identified WT-1 derived peptide. Yoshida reported the development of novel liposome which not only work as a delivery system but also as a adjuvant. The effect of siRNA encapsulated in their liposome against malignant glioma cells was shown. Tahara reported the identification of epitope peptide derived from human vascular endothelial growth factor receptor 2 (VEGFR2). He informed that they started a phase 1 clinical trial in University of Tokyo based on their findings. Kadowaki reported that plasmacytoid DC (pDC) express TLR7 and TLR9, and therefore can react to CpG suggesting a positive rile in cancer immunotherapy. On the other hand, pDC can produce IFNα which sometimes induce regulatory T cells, suggesting a paradoxical role for pDC in anti-tumor immunity. As a summary of this session, it was clear that many researchers have realized the importance to induce a variety sets of immune cells including cells in innate and acquired immunity, and to overcome the immunosuppressive state of cancer patients. For this purpose, several strategies including (1) use of proteins and DNAs as antigen, (2) use of adjuvant such as CpG to activate innate immunity especially type 1 sifted immunity, (3) use of delivery systems such as liposome or CHP, (4) use of cell therapy such as dendritic cells or Th1 cells, have been developed. Many of them were already in phase 1 clinical trial. It was too early to evaluate the clinical effect of these trials, but it was suggested that they were promising. It was realized that the system for the translational research in Japan is not efficient enough, and that it was an urgent requirement to develop an efficient translational research by the collaboration with LICR, CRI, and CVC in USA.
During this seminar, it was shown that the development of the 2nd generation of cancer vaccine therapy is on going in many institutions. It will require approximately 5 years to test the clinical effect of these 2nd generation of cancer vaccine therapy. The collaboration of US researchers and Japan researchers was suggested to facilitate strongly the development of efficient 2nd generation of cancer vaccine therapy to benefit many cancer patients.