title: Relationship between genotoxic effects of breast cancer treatments and patient basal DNA integrity.
abstract: Radiotherapy and chemotherapy cause genotoxic side effects that are highly variable among patients. In this study, we evaluated DNA integrity using the comet assay in peripheral blood lymphocytes from breast cancer patients before ("pre-treatment patients"; n=47) and after ("post-treatment patients"; n=24) radiotherapy and/or chemotherapy treatment and from healthy donors (n=15). Comet evaluation was made by visual (types 0-4) and digital (percentage of DNA remaining in the comet head=% head DNA) analysis. The association between the level of DNA damage and cancer prognostic factors was assessed. The treatments caused a significant increase in DNA damage registered by both visual (p<0.001) and digital (p<0.001) analyses. No significant associations between the level of DNA damage in pre-treatment patients and cancer prognostic factors were found. A significant correlation between the comet results from each patient before and after treatment (r=0.64, p=0.001) was observed. The % head DNA in post-treatment samples from patients with a high level of DNA damage before treatment (30.3±3.1%, p<0.01) was lower than in post-treatment samples from patients with a low-to-medium level of DNA damage before therapy (49.2±4.4%). These results support the usefulness of the comet assay as a sensitive technique to evaluate basal DNA status and DNA damage caused by cancer treatments. The comet assay could contribute to treatment decisions, especially by taking into account the patient's basal DNA damage before therapy.
authors.affiliation: Institute of Experimental Physiology (IFISE), Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET), Facultad de Ciencias Bioquimicas y Farmaceuticas, Universidad Nacional de Rosario, Suipacha 531 (2000) Rosario, Argentina.
authors.forename: María Paula
authors.initials: MP
authors.lastname: Ceballos
authors.affiliation: Mastology service of the Centenario Hospital, Urquiza 3101 (2000) Rosario, Argentina.
authors.forename: Juan Capitaine
authors.initials: JC
authors.lastname: Funes
authors.affiliation: Area of Clinical Biochemistry, Facultad de Ciencias Bioquimicas y Farmaceuticas, Universidad Nacional de Rosario, Suipacha 531 (2000) Rosario, Argentina.
authors.forename: Estefanía
authors.initials: E
authors.lastname: Massa
authors.affiliation: Mastology service of the Centenario Hospital, Urquiza 3101 (2000) Rosario, Argentina.
authors.forename: Germán
authors.initials: G
authors.lastname: Cipulli
authors.affiliation: Mastology service of the Provincial Hospital, Alem 1450 (2000) Rosario, Argentina.
authors.forename: Alfonso Benitez
authors.initials: AB
authors.lastname: Gil
authors.affiliation: Mastology service of the Centenario Hospital, Urquiza 3101 (2000) Rosario, Argentina.
authors.forename: Carlos Capitaine
authors.initials: CC
authors.lastname: Funes
authors.affiliation: Mastology service of the Centenario Hospital, Urquiza 3101 (2000) Rosario, Argentina.
authors.forename: Roberto
authors.initials: R
authors.lastname: Tozzini
authors.affiliation: Area of Clinical Biochemistry, Facultad de Ciencias Bioquimicas y Farmaceuticas, Universidad Nacional de Rosario, Suipacha 531 (2000) Rosario, Argentina.
authors.forename: Sergio
authors.initials: S
authors.lastname: Ghersevich
mesh_terms: D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000188:drug therapy / Q000532:radiotherapy / Q000628:therapy*; D020552:Comet Assay; D004273:DNA, Neoplasm / Q000235:genetics*; D005260:Female; D006801:Humans; D008875:Middle Aged; D009153:Mutagens / Q000633:toxicity*; D055815:Young Adult
chemical_list: D004273:DNA, Neoplasm; D009153:Mutagens