Autor(es): Esteves, Filipa ; Amaro, Raquel ; Silva, Susana ; Costa, Solange ; Costa, Carla ; Bolognesi, Claudia ; Teixeira, João Paulo
Data: 2018
Identificador Persistente: http://hdl.handle.net/10400.18/5521
Origem: Repositório Científico do Instituto Nacional de Saúde
Assunto(s): Cancer; Exposure to Genotoxicants; Biomarkers; Urine Derived Cells (UDC); Genotoxicidade Ambiental; Toxicologia
Epidemiological studies commonly associate the incidence of cancers with the exposure to genotoxicants. This exposure may be analyzed using effect biomarkers allowing an early detection of health alterations. Micronucleus assay constitutes a useful tool to detect chromosomal damage, genomic instability and carcinogenic events. Cancers are usually from epithelial origin, and therefore micronucleus test (MN) in urine derived cells (UDC) assumes a great role on toxicological studies. Sampling of UDC is an easy and minimally invasive procedure, representing an advantage in human biomonitoring studies. The main concern related with UDC is the lack of standardization of MN protocol. Data show a large variability of the method, in particular what concerns to staining procedure, which may lead to bias. The use of different methodologies regarding MN in UDC may contribute to the large inter-laboratory variations and consequently for inconsistencies among studies. Aim: i) Select the most reliable method to stain UDC of those most commonly used - Giemsa and Feulgen. Giemsa - staining permits a quick preparation of slides for microscopic evaluation, however it is a non-DNA-specific stain which may favor false positive readings through the presence of other cellular structures (nonnuclear bodies, bacteria or keratohyalin granules). Feulgen - staining, although more time consuming, is a DNA specific stain which allows a good contrast between DNA material and cytoplasm; ii) Establish a detailed set of criteria for scoring all of the biomarkers in UDC; iii) Standardize the application of the mn assay in UDC.
