title: Role of DNA methylation in the adaptive responses induced in a human B lymphoblast cell line by long-term low-dose exposures to γ-rays and cadmium.
abstract: The possible involvement of epigenetic factors in health risks due to exposures to environmental toxicants and ionizing radiation is poorly understood. We have tested the hypothesis that DNA methylation contributes to the adaptive response (AR) to ionizing radiation or Cd. Human B lymphoblast cells HMy2.CIR were irradiated (0.032 Gy γ-rays) three times per week for 4 weeks or exposed to CdCl2 (0.005, 0.01, or 0.1 μM) for 3 months, and then challenged with a high dose of Cd (50 or 100 μM) or γ-rays (2 Gy). Long-term low-dose radiation (LDR) or long-term low-dose Cd exposure induced AR against challenging doses of Cd and irradiation, respectively. When the primed cells were treated with 5-aza-2'-deoxycytidine (5-aza-dC), a DNA methyltransferase inhibitor, the ARs were eliminated. These results indicate that DNA methylation is involved in the induction of AR in HMy2.CIR cells.
authors.affiliation: Institute of Radiation Medicine, Fudan University, No. 2094, Xietu Road, Shanghai 200032, China; Ningbo Medical Center, Lihuili Hospital, No. 57, Xingning Road, Ningbo 315041, Zhejiang, China.
authors.forename: Shuang
authors.initials: S
authors.lastname: Ye
authors.affiliation: Institute of Radiation Medicine, Fudan University, No. 2094, Xietu Road, Shanghai 200032, China.
authors.forename: Dexiao
authors.initials: D
authors.lastname: Yuan
authors.affiliation: Institute of Radiation Medicine, Fudan University, No. 2094, Xietu Road, Shanghai 200032, China.
authors.forename: Yuexia
authors.initials: Y
authors.lastname: Xie
authors.affiliation: Institute of Radiation Medicine, Fudan University, No. 2094, Xietu Road, Shanghai 200032, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Pan
authors.affiliation: Institute of Radiation Medicine, Fudan University, No. 2094, Xietu Road, Shanghai 200032, China. Electronic address: clshao@shmu.edu.cn.
authors.forename: Chunlin
authors.initials: C
authors.lastname: Shao
mesh_terms: D000222:Adaptation, Physiological / Q000235:genetics*; D001402:B-Lymphocytes / Q000187:drug effects* / Q000378:metabolism / Q000528:radiation effects*; D002104:Cadmium / Q000633:toxicity*; D002273:Carcinogens / Q000633:toxicity*; D002461:Cell Line, Transformed; D004249:DNA Damage; D019175:DNA Methylation / Q000502:physiology*; D004305:Dose-Response Relationship, Drug; D004307:Dose-Response Relationship, Radiation; D004785:Environmental Pollutants / Q000633:toxicity*; D005720:Gamma Rays / Q000009:adverse effects; D006801:Humans; D015162:Micronucleus Tests
chemical_list: D002273:Carcinogens; D004785:Environmental Pollutants; D002104:Cadmium
keywords: Adaptive response; DNA methylation; Low-dose cadmium; Low-dose radiation; Lymphoblast