Mutation induction by ionizing radiation in three human bladder tumour cell lines.
Mutation induction at the hypoxanthine-guanine phosphoribosyl transferase (hprt) locus has been studied in three human bladder tumour cell lines of varying radiosensitivity. U1-S40b, a radiosensitive mutant clone of MGH-U1, has been previously reported to show no difference in split-dose recovery or low dose-rate sparing, but to have an impaired repair fidelity when compared to its parent line. In this paper we have shown that U1-S40b is less mutable at the hprt locus at a similar level of survival. This may represent an increased incidence of severe or non-repairable lesions, making hprt- mutants poorly recoverable in U1-S40b when compared to MGH-U1. No difference was seen in mutation induction between MGH-U1 and RT112, another human bladder tumour cell line of similar radiosensitivity to MGH-U1.
Kent
C R
CR
Radiotherapy Research Unit, Institute of Cancer Research, Sutton, Surrey, UK.
Edwards
S M
SM
McMillan
T J
TJ
D002295:Carcinoma, Transitional Cell / Q000235:genetics*; D002470:Cell Survival / Q000235:genetics; D003037:Cobalt Radioisotopes; D004307:Dose-Response Relationship, Radiation; D005720:Gamma Rays; D006801:Humans; D007041:Hypoxanthine Phosphoribosyltransferase / Q000235:genetics; D066298:In Vitro Techniques; D009154:Mutation; D011830:Radiation Effects; D014407:Tumor Cells, Cultured / Q000528:radiation effects; D001749:Urinary Bladder Neoplasms / Q000235:genetics*
D003037:Cobalt Radioisotopes; D007041:Hypoxanthine Phosphoribosyltransferase