Quantification of DNA repair capacity in whole blood of patients with head and neck cancer and healthy donors by comet assay.
Mutat Res
; 650(1): 55-62, 2008 Jan 31.
Article
em En
| MEDLINE
| ID: mdl-18032094
ABSTRACT
Comet assay has been used to estimate cancer risk by quantification of DNA damage and repair in response to mutagen challenge. Our goal was to adopt best practices for the alkaline comet assay to measure DNA repair capacity of white blood cells in whole blood of patients with squamous cell carcinoma of the head and neck (HNSCC). The results show that initial damage by 10 Gy of gamma radiation expressed as percent DNA in comet tail was higher in stimulated lymphocytes (61.1+/-11.8) compared to whole blood (43.0+/-12.1) but subsequent repair was similar with comet tail of approximately 20% at 15 min and 13% at 45 min after exposure. Exposure of whole blood embedded in agarose from 5 to 10 Gy gamma radiation was followed by an approximately 70% repair of the DNA damage within 45 min with a faster repair phase in the first 15 min. Variability of the measurement was lower within repeated measurements of the same person compared to measurement of different healthy individuals. The repair during first 15 min was slower (p=0.01) in ex-/non-smokers (41.0+/-2.1%) compared to smokers (50.3+/-2.7%). This phase of repair was also slower (p=0.02) in HNSCC patients (36.8+/-2.1%) compared to controls matched on age and smoking (46.4+/-3.0%). The results of this pilot study suggest that quantification of repair in whole blood following a gamma radiation challenge is feasible. Additional method optimization would be helpful to improve the assay for a large population screening.
Texto completo:
1
Bases de dados:
MEDLINE
Assunto principal:
Carcinoma de Células Escamosas
/
Ensaio Cometa
/
Reparo do DNA
/
Neoplasias de Cabeça e Pescoço
Tipo de estudo:
Guideline
/
Observational_studies
/
Risk_factors_studies
Limite:
Aged
/
Humans
/
Middle aged
Idioma:
En
Revista:
Mutat Res
Ano de publicação:
2008
Tipo de documento:
Article
País de afiliação:
Estados Unidos