Archives of Head and Neck Surgery
Archives of Head and Neck Surgery
Original Article Carcinogenesis, tumor biology and tumor markers

Comet and micronucleus assays do not correlate extent of DNA damage with clinical staging of oral cavity squamous cell carcinoma

Andreza Negreli Santos, Rodrigo Juliano Oliveira, Lucas Roberto Pessatto, Albert Schiavetto Souza, Andréia Conceição Milan Brochado Antoniolli-Silva, Andrea Luiza Cunha-Laura, Maria Margarida Morena Domingos Levenhagen, Carlos Alberto Ferreira de Freitas

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Introduction: Oral cavity squamous cell carcinoma is the sixth most frequent malignant neoplasm worldwide. Its main etiological factor is smoking associated with alcohol consumption. Objective: To evaluate the applicability of the comet and micronucleus assays and the relationship between cell damage intensity and oral cavity squamous cell carcinoma (OCSCC) clinical stages. Methods: A total of 44 individuals, 24 oral cancer patients and 20 healthy volunteers, participated in the study. Exfoliated cells were collected from the oral cavity using a wooden spatula. All samples were analyzed by the comet (CA), micronucleus (MNA) and cell death (CDA) assays. Results: The diagnosis of OCSCC increases the frequency of genotoxic damage (CA – 3.21x; MNA – 3.93x); however, it was not possible to establish a correlation between frequency of DNA damage and disease staging. The CDA was not effective for the proposed biomonitoring. Conclusion: The CA and MNA were considered adequate for biomonitoring DNA damage. With the current design, the applicability of these assays to correlate DNA/cell damage extent and OCSCC clinical staging could not be demonstrated. Nevertheless, further studies should be conducted with larger sample sizes to increase the statistical power of these findings.


genotoxicity; comet assay; micronucleus assay; apoptosis; biomonitoring; oral cancer.


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