Reiko Ito


Department of Molecular Biosciences
Contact us here.


The overall goal of her research is to understand associations between radiation exposure and pathogenesis of diseases developed among atomic-bomb survivors. At RERF, there are so many pathological tissues collected from atomic-bomb victims (e.g., glass slides specimens, paraffin-embedded tissue blocks, frozen sera, etc.). These samples should be pathologically reviewed, in association with epidemiological endpoints such as radiation dose, gender, age at the time of radiation exposure, age at disease onset, and so on. Especially, carcinomas need detailed analyses including molecular analyses, to determine associations of various pathological parameters (such as latency period, histological grade, microenvironment feature, and gene expression) with those epidemiological data.
One of her major interests is the study of molecular mechanisms on radiation-related digestive tract carcinomas. Given many distinct molecular pathways for carcinogenesis of digestive tract carcinomas, this study aims to find one or more pathways that are preferentially affected by radiation exposure and highly associated with histological alterations.


Ph.D., DDS. Graduate School of Dentistry, Hiroshima University
Scholar Resident, 1st Pathology, Graduate School of Medicine, Hiroshima University
DDS. Hiroshima University School of Dentistry


Radiation Effects Research Foundation
  • 2016-

    Associate Senior Scientist, Department of Molecular Biosciences

  • 2012-2016

    Associate Senior Scientist, Department of Radiobiology/Molecular Epidemiology

  • 2004-2012

    Research Scientist, Department of Radiobiology/Molecular Epidemiology

Hiroshima University
  • 2008-

    Visiting Associate Professor, Graduate School of Biomedical Sciences

  • 2004

    Associate professor, Department of Molecular Pathology, Graduate School of Biomedical Sciences

  • 2002-2004

    Research Associate, Department of Molecular Pathology, Graduate School of Biomedical Sciences, Hiroshima, Japan

  • 2001-2002

    Research Associate, 1st Department of Pathology, Hiroshima University School of Medicine

Osaka University
  • 1999-2000

    Visiting Scholar, Cancer Center, University of California, San Diego, USA

  • 1996-2001

    Research Associate, Department of Oral Pathology, Faculty of Dentistry

Hiroshima University Hospital
  • 1995-1996


Selected publications

Ito R, Hale LP, Geyer SM, Jie Li, Sornborger A, Kajimura J, Kusunoki Y, Yoshida K, van den Brink MRM, Kyoizumi S, Manley NR, Nakachi K, Sempowski GD. Late effects of ionizing radiation exposure and age on human thymus morphology and function. Radiat Res. 2017; 187: 589-598.
Ito R, Hamatani K, Yano S, Shinohara T, Takahashi K, Yasui W, Nakachi K, Kusunoki Y. Microsatellite instability (MSI) and MLH1 alteration in colorectal cancer among A-bomb survivors. Hiroshima Igaku [J Hiroshima Med Assoc]. 2014; 67(4):356-60.
Hayashi T, Ito R, Cologne JB, Maki M, Morishita Y, Nagamura H, Sasaki K, Hayashi I, Imai K, Yoshida K, Kajimura J, Kyoizumi S, Kusunoki Y, Ohishi W, Fujiwara S, Akahoshi M, Nakachi K. Effects of IL-10 haplotype and atomic bomb radiation exposure on gastric cancer risk. Radiat Res. 2013; 180(1):60-9.
Hamatani K, Eguchi H, Mukai M, Takahashi K, Ito R, Taga M, Imai K, Cologne J, Soda M, Arihiro K, Fujihara M, Abe K, Hayashi T, Nakashima M, Sekine I, Yasui W, Hayashi Y, Nakachi K. RET/PTC rearrangements preferentially occurred in papillary thyroid cancer among atomic bomb survivors exposed to high radiation dose. Cancer Res. 2008; 68: 7176-7182.
Ito R, Oue N, Yoshida K, Kunimitsu K, Nakayama H, Nakachi K, Yasui W. Clinicopathological significant and prognostic influence of cadherin-17 expression in gastric cancer. Virchows Arch. 2005; 447:717-722.
Ito R, Nakayama H, Yoshida K, Matsumura S, Oda N, Yasui W. Expression of Cbl linking with the epidermal growth factor receptor system isassociated with tumor progression and poor prognosis of human gastric carcinoma. Virchows Arch. 2004; 444:324-331.
Ito R, Oue N, Zhu X, Yoshida K, Nakayama H, Yokozaki H and Yasui W. Expression of integrin-linked kinase is closely correlated with invasion and metastasis of gastric carcinoma. Virchow Arch. 2003; 442:118-123.
Ito R, Yasui W, Ogawa Y, Toyosawa S, Tahara E and Ijuhin N. Reduced expression of cyclin-dependent kinase inhibitor p27/Kip1 in oral malignant tumors. Pathobiol. 1999; 67: 169-173.
Ito R, Yasui W, Yokozaki H, Yamashita U, Takata T, Nikai H and Tahara E. Growth stimulatory effect of interleukin (IL)-1α produced by oral squamous carcinoma cell lines. Int J Oncol. 1997; 11: 807-812.
Ito R, Kitadai Y, Kyo E, Yokozaki H, Yasui W, Yamashita U, Nikai H and Tahara E. Interleukin 1α acts as an autocrine growth stimulator for human gastric carcinoma cells. Cancer Res 1993; 53: 4102-4106.