The effect of postirradiation holding at 22[degrees]C on the repair of sublethal, potentially lethal and potentially neoplastic transforming damage in gamma-irradiated HeLa x skin fibroblast human hybrid cells

Journal Article · Tue Mar 01 00:00:00 EST 1994 · Radiation Research; (United States)

DOI:https://doi.org/10.2307/3578706· OSTI ID:6440613

Redpath, J L; Antoniono, R J; Mendonca, M S; Sun, C ^[1]

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1. Univ. of California, Irvine, CA (United States)

The effect of postirradiation holding at 22[degrees]C on cell growth, progression of cells through the cell cycle, and the repair of sublethal, potentially lethal and potentially neoplastic transforming damage in [gamma]-irradiated HeLa x skin fibroblast human hybrid cells has been examined. Cell growth and cell cycle progression were essentially stopped at this reduced temperature. Cell survival was dramatically reduced by holding confluent cultures for 6 h at 22[degrees]C, as opposed to 37[degrees]C, after 7.5 Gy [gamma] radiation delivered at a rate of 2 Gy/min. Return of the cells to 37[degrees]C for 6 h after holding at 22[degrees]C did not result in increased survival. A similar effect was obtained when the cells were held at 22[degrees]C between split-dose irradiation of log-phase cultures where no increase in survival was observed over a split-dose interval of 4 h. In this case a partial increase in survival was observed upon returning the cells to 37[degrees]C for 3 h after holding at 22[degrees]C for the first 3 h of the split-dose interval. Neoplastic transformation frequency was not enhanced by holding confluent cultures for 6 h at 22[degrees]C after 7.5 Gy [gamma] radiation. This is consistent with previous observations that misrepair of potentially neoplastic transforming damage already occurs at 37[degrees]C. The overall results are interpreted in terms of the reduced temperature favoring misrepair, rather than inhibition of repair, of sublethal, potentially lethal and potentially transforming radiation damage. 24 refs., 5 figs., 3 tabs.

• OSTI ID: 6440613
• Journal Information: Radiation Research; (United States), Vol. 137:3; ISSN 0033-7587
• Country of Publication: United States
• Language: English

Related Subjects

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
BIOLOGICAL REPAIR
TEMPERATURE DEPENDENCE
HELA CELLS
MORTALITY
BIOLOGICAL RADIATION EFFECTS
CELL CYCLE
DOSE-RESPONSE RELATIONSHIPS
FIBROBLASTS
GAMMA RADIATION
GROWTH
LETHAL IRRADIATION
SUBLETHAL IRRADIATION
ANIMAL CELLS
BIOLOGICAL EFFECTS
BIOLOGICAL RECOVERY
CONNECTIVE TISSUE CELLS
ELECTROMAGNETIC RADIATION
IONIZING RADIATIONS
IRRADIATION
RADIATION EFFECTS
RADIATIONS
REPAIR
SOMATIC CELLS
560120* - Radiation Effects on Biochemicals
Cells
& Tissue Culture