Genotoxic effects of radiotherapy and chemotherapy on the circulating lymphocytes of breast cancer patients. II. Alteration of DNA repair and chromosome radiosensitivity.
Lymphocytes from 43 breast cancer patients were tested for their DNA-repair ability and in vitro chromosomal radiosensitivity. Lymphocytes were collected before and after treatment with radiotherapy or chemotherapy or both, and then irradiated in vitro. The aim was to detect alterations of these 2 indicators of radiosensitivity, in relation to cancer status or medical treatment. Patients before treatment were significantly deficient in DNA-repair ability but had a normal chromosomal radiosensitivity as compared to healthy donors. When assessed after treatment, DNA-repair ability and the frequency of in vitro-induced chromosome anomalies were modified according to the type of treatment. A reduced DNA-repair ability was observed for patients after radiotherapy but not after chemotherapy. In vitro-induced dicentrics and acentrics were not modified to the same extent according to the treatment. A decreased number of acentrics (the most frequently observed alteration) was preferentially associated with a more reduced DNA-repair ability. Interindividual differences of response to in vitro irradiation tested by both assays were observed between patients who had undergone similar treatments. The possibility that these assays could be used for predicting individual susceptibility to radiation or chemotherapy drug exposure is discussed.
Rigaud
O
O
Commissariat à l'Energie Atomique, I.P.S.N./D.P.S., Fontenay aux Roses, France.
Guedeney
G
G
Duranton
I
I
Leroy
A
A
Doloy
M T
MT
Magdelenat
H
H
D000328:Adult; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D001943:Breast Neoplasms / Q000188:drug therapy / Q000235:genetics* / Q000532:radiotherapy; D002869:Chromosome Aberrations; D003131:Combined Modality Therapy; D003520:Cyclophosphamide / Q000008:administration & dosage; D004260:DNA Repair / Q000187:drug effects / Q000528:radiation effects; D004317:Doxorubicin / Q000008:administration & dosage; D005472:Fluorouracil / Q000008:administration & dosage; D006801:Humans; D008214:Lymphocytes / Q000187:drug effects / Q000528:radiation effects; D008875:Middle Aged
D004317:Doxorubicin; D003520:Cyclophosphamide; D005472:Fluorouracil