Persistent Increased Frequency of Genomic Instability in Women Diagnosed with Breast Cancer: Before, during, and after Treatments

• Published in: Oxidative medicine and cellular longevity 2018-01, Vol.2018 (2018), p.1-10
• Main Authors: Islam, Muhammad Torequl, de Carvalho Melo Cavalcante, Ana Amélia, Silva, Juliana da, de Carvalho, Rodrigo Mendes, de Alencar, Marcus Vinícius Oliveira Barros, da Mata, Ana Maria Oliveira Ferreira, Júnior, Antonio Luiz Gomes, Grivicich, Ivana, Picada, Jaqueline N., Sobral, André Luiz Pinho, Paz, Marcia Fernanda Correia Jardim, Machado, Kátia da Conceição
• Format: Article
• Language: English
• Subjects: Adult; Breast cancer; Breast Neoplasms - genetics; Cancer; Cancer therapies; Care and treatment; Cells, Cultured; Chemotherapy; Comet Assay; Deoxyribonucleic acid; Development and progression; DNA; DNA damage; DNA Damage - drug effects; DNA Damage - genetics; DNA repair; Endocrine therapy; Female; Gene expression; Genetic aspects; Humans; Hydrogen Peroxide - metabolism; Hydrogen Peroxide - pharmacology; Mammography; Medical prognosis; Micronucleus Tests; Middle Aged; Mutagenesis; Mutation; Oncology, Experimental; Oxidative Stress - drug effects; Patients; Radiation therapy; Radiotherapy; Women; Womens health
• ISSN: 1942-0900; 1942-0994
• DOI: 10.1155/2018/2846819

This study aimed to evaluate DNA damage in patients with breast cancer before treatment (background) and after chemotherapy (QT) and radiotherapy (RT) treatment using the Comet assay in peripheral blood and the micronucleus test in buccal cells. We also evaluated repair of DNA damage after the end of RT, as well as the response of patient’s cells before treatment with an oxidizing agent (H2O2; challenge assay). Fifty women with a mammographic diagnosis negative for cancer (control group) and 100 women with a diagnosis of breast cancer (followed up during the treatment) were involved in this study. The significant DNA damage was observed by increasing in the index and frequency of damage along with the increasing of the frequency of micronuclei in peripheral blood and cells of the buccal mucosa, respectively. Despite the variability of the responses of breast cancer patients, the individuals presented lesions on the DNA, detected by the Comet assay and micronucleus Test, from the diagnosis until the end of the oncological treatment and were more susceptible to oxidative stress. We can conclude that the damages were due to clastogenic and/or aneugenic effects related to the neoplasia itself and that they increased, especially after RT.