Defective repair of UV-damaged DNA in human tumor and SV40-transformed human cells but not in adenovirus-transformed human cells.
The DNA repair capacities of five human tumor cell lines, one SV40-transformed human cell line and one adenovirus-transformed human cell line were compared with that of normal human fibroblasts using a sensitive host cell reactivation (HCR) technique. Unirradiated and UV-irradiated suspensions of adenovirus type 2 (Ad 2) were assayed for their ability to form viral structural antigens (Vag) in the various cell types using immunofluorescent staining. The survival of Vag formation for UV-irradiated Ad 2 was significantly reduced in all the human tumor cell lines and the SV40-transformed human line compared to the normal human fibroblasts, but was apparently normal in the adenovirus-transformed human cells. D0 values for the UV survival of Ad 2 Vag synthesis in the tumor and virally transformed lines expressed as a percentage of that obtained on normal fibroblast strains were used as a measure of DNA repair capacity. Percent HCR values ranged from 26 to 53% in the tumor cells. These results indicate a deficiency in the repair of UV-induced DNA damage associated with human tumorigenesis and the transformation of human cells by SV40 but not the transformation of human cells by adenovirus.
Rainbow
A J
AJ
Department of Biology, McMaster University, Hamilton, Ontario, Canada.
D000260:Adenoviruses, Human / Q000235:genetics*; D002460:Cell Line; D002471:Cell Transformation, Neoplastic / Q000528:radiation effects*; D004249:DNA Damage; D004260:DNA Repair / Q000528:radiation effects*; D004273:DNA, Neoplasm / Q000235:genetics / Q000528:radiation effects*; D004307:Dose-Response Relationship, Radiation; D006801:Humans; D013539:Simian virus 40 / Q000235:genetics*; D014407:Tumor Cells, Cultured / Q000528:radiation effects*; D014466:Ultraviolet Rays
D004273:DNA, Neoplasm