| The radiation response of cells recovering after chronic hypoxia. | |
| | |
MedLine Citation:
|
PMID: 2756117 Owner: NLM Status: MEDLINE |
Abstract/OtherAbstract:
|
Experiments were performed to study the influence of hypoxic pretreatment on the radiation response of A431 human squamous carcinoma cells. Reaeration for 10 min after chronic hypoxia (greater than 2 h) was found to enhance the radiosensitivity of A431 cells, and the maximal effect was seen for those cells reaerated after 12 h of hypoxia. The radiosensitivity enhancement for reaerated cells after 12 h of hypoxia was maximized by 5 min after the return to aerobic conditions and reached the control level by 12 h of reaeration. This enhanced radiosensitive state was characterized by a reduced shoulder region and increased slope of the radiation dose-response curve for cells in both the exponential and plateau phases of growth. There was a slight increase in the number of G1 and decrease in the number of S and G2 + M cells for both exponential- and plateau-phase cultures following 12 h hypoxic treatment. Although growth inhibition induced by 12 h of hypoxia was seen for cells in the exponential phase, there was no cell number change in the plateau-phase culture after hypoxia. Plating efficiency (PE) of cells in both growth phases was reduced by 30% after hypoxia. Furthermore, in the exponential-phase culture, the extent of reduction in PE after hypoxia was similar among cells in different phases of the cell cycle. Although S-phase cells in exponentially growing cultures were relatively more resistant to radiation than G1 and G2 + M cells, the cell age-response pattern was the same whether the cells had been aerobic or hypoxic before reaeration and irradiation. Furthermore, the enhancement ratio associated with reaeration after 12 h of hypoxia for these three subpopulations of cells was 1.3. Our results indicate that the increase in radiosensitivity due to reaeration after chronic hypoxia is unlikely to be related to the changes of cell cycle stage and growth phase during hypoxic treatment. |
| | |
Authors:
|
T T Kwok; R M Sutherland |
Related Documents
:
|
12727827 - Redox regulation of the g1 to s phase transition in the mouse embryo fibroblast cell cy... 7882457 - Synchronization of cells in the s phase of the cell cycle by 3'-azido-3'-deoxythymidine... 17891177 - S-phase progression stimulates both the mutagenic ku-independent pathway and mutagenic ... 22417827 - Expression of prohibitins on the surface of activated t cells. 8859887 - Postnatal development of cell types in the hamster harderian gland. 11040047 - G(1) phase-dependent expression of bcl-2 mrna and protein correlates with chemoresistan... |
Publication Detail:
|
Type: Journal Article; Research Support, Non-U.S. Gov't |
Journal Detail:
|
Title: Radiation research Volume: 119 ISSN: 0033-7587 ISO Abbreviation: Radiat. Res. Publication Date: 1989 Aug |
Date Detail:
|
Created Date: 1989-09-01 Completed Date: 1989-09-01 Revised Date: 2006-11-15 |
Medline Journal Info:
|
Nlm Unique ID: 0401245 Medline TA: Radiat Res Country: UNITED STATES |
Other Details:
|
Languages: eng Pagination: 261-7 Citation Subset: IM; S |
Affiliation:
|
Experimental Therapeutics Division, University of Rochester, New York 14642. |
Export Citation:
|
APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
|
Aerobiosis Anaerobiosis Cell Division / radiation effects Cell Line Cell Survival / radiation effects Colony-Forming Units Assay Humans Oxygen / physiology* Radiation Tolerance* |
| Chemical | |
Reg. No./Substance:
|
7782-44-7/Oxygen |
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
Previous Document: Comparative effects of caffeine on radiation- and heat-induced alterations in cell cycle progression...
Next Document: Effect of inhaled alpha-emitting nuclides on mouse alveolar macrophages.