title: ICRP Publication 131: Stem cell biology with respect to carcinogenesis aspects of radiological protection.
abstract: Current knowledge of stem cell characteristics, maintenance and renewal, evolution with age, location in 'niches', and radiosensitivity to acute and protracted exposures is reviewed regarding haematopoietic tissue, mammary gland, thyroid, digestive tract, lung, skin, and bone. The identity of the target cells for carcinogenesis continues to point to the more primitive and mostly quiescent stem cell population (able to accumulate the protracted sequence of mutations necessary to result in malignancy), and, in a few tissues, to daughter progenitor cells. Several biological processes could contribute to the protection of stem cells from mutation accumulation: (1) accurate DNA repair; (2) rapid induced death of injured stem cells; (3) retention of the intact parental strand during divisions in some tissues so that mutations are passed to the daughter differentiating cells; and (4) stem cell competition, whereby undamaged stem cells outcompete damaged stem cells for residence in the vital niche. DNA repair mainly operates within a few days of irradiation, while stem cell replications and competition require weeks or many months depending on the tissue type. This foundation is used to provide a biological insight to protection issues including the linear-non-threshold and relative risk models, differences in cancer risk between tissues, dose-rate effects, and changes in the risk of radiation carcinogenesis by age at exposure and attained age.
authors.affiliation: Christie Medical Physics and Bioengineering, Christie Hospital NHS Foundation Trust and University of Manchester, Manchester M20 4BX, UK jhendry2002uk@yahoo.com.
authors.forename: J H
authors.initials: JH
authors.lastname: Hendry
authors.affiliation: Fukushima Medical University and Radiation Effects Research Foundation, Japan.
authors.forename: O
authors.initials: O
authors.lastname: Niwa
authors.affiliation: Radiation Oncology and Cell Biology, New York University School of Medicine, USA.
authors.forename: M H
authors.initials: MH
authors.lastname: Barcellos-Hoff
authors.affiliation: Bone and Signaling Laboratory, Space Biosciences Research Branch, NASA Ames Research Center, USA.
authors.forename: R K
authors.initials: RK
authors.lastname: Globus
authors.affiliation: Centre for Radiation, Chemical and Environmental Hazards, Health Protection Directorate, Public Health England, UK.
authors.forename: J D
authors.initials: JD
authors.lastname: Harrison
authors.affiliation: Laboratoire de Genomique et Radiobiologie de la Kertinopoiese, CEA, France.
authors.forename: M T
authors.initials: MT
authors.lastname: Martin
authors.affiliation: Tech Micro Services Co., USA.
authors.forename: T M
authors.initials: TM
authors.lastname: Seed
authors.affiliation: Radiation Oncology, Simmons Cancer Center, University of Texas, Southwestern Medical Center, USA.
authors.forename: J W
authors.initials: JW
authors.lastname: Shay
authors.affiliation: Radiation Oncology, Simmons Cancer Center, University of Texas, Southwestern Medical Center, USA.
authors.forename: M D
authors.initials: MD
authors.lastname: Story
authors.affiliation: Radiation Medical Sciences, Atomic Bomb Disease Institute, Nagasaki University, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Suzuki
authors.affiliation: Radiation Medical Sciences, Atomic Bomb Disease Institute, Nagasaki University, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Yamashita
mesh_terms: D063646:Carcinogenesis; D004307:Dose-Response Relationship, Radiation; D006801:Humans; D009381:Neoplasms, Radiation-Induced / Q000209:etiology*; D000069079:Radiation Exposure; D011835:Radiation Protection; D018570:Risk Assessment; D013234:Stem Cells / Q000528:radiation effects*
keywords: Carcinogenesis; Mutations; Radiation risk; Radiobiology; Stem cells