UVC-induced expression of a tumor-associated antigen in human cell hybrids (HeLa X skin fibroblasts): repair of potentially lethal and potentially transforming damage.
The UVC-induced expression of a cell surface protein which correlates with the induction of tumorigenicity has been observed in human cell hybrids (HeLa X skin fibroblasts). A dose - response curve for the induction of this marker of neoplastic transformation has been obtained. Studies of the repair of potentially lethal and potentially transforming damage indicate a slow repair process which results in enhanced survival and decreased neoplastic transformation over the period 6-24 h post-treatment. The kinetics of this repair process are consistent with previously published work on the kinetics of removal of thymine dimers from UVC-irradiated human skin fibroblasts. During the first few hours post-irradiation (0-6 h) there are fluctuations in transformation frequency while survival remains essentially constant. It is during this period that 6-4 photoproducts are removed from UV-irradiated DNA. It is possible that repair of these lesions may lead to an increase in transformation frequency and have no impact in terms of survival.
Redpath
J L
JL
Department of Radiological Sciences, University of California, Irvine 92717.
Sun
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D000951:Antigens, Neoplasm / Q000378:metabolism*; D002470:Cell Survival; D002471:Cell Transformation, Neoplastic; D004260:DNA Repair; D004307:Dose-Response Relationship, Radiation; D005347:Fibroblasts; D006367:HeLa Cells; D006801:Humans; D006822:Hybrid Cells; D014466:Ultraviolet Rays
D000951:Antigens, Neoplasm