DNA damage in buccal cells in oral PMDs and malignant disorders by comet assay

a comparison with blood leukocytes

  • Garima Rawat Dharamshila Narayana Hospital
  • Aadithya B Urs Maulana Azad Institute of Dental Sciences https://orcid.org/0000-0002-1299-5805
  • Anita Chakravarti Maulana Azad Medical College
  • Priya Kumar Maulana Azad Institute of Dental Sciences
Keywords: Comet assay, DNA damage, Epithelial cells, Leukocytes, Mouth neoplasms.


Aim: DNA damage associated with Oral Squamous Cell Carcinoma (OSCC) and potentially malignant disorders (PMDs) is produced due to carcinogenic agents or increased oxidative stress. Comet assay can assist in early detection and evaluation of the amount of DNA damage; lymphocytesare the most commonly used cells for performing comet assay. Utilisation of buccal epithelial cells in comet assay can be a minimally invasive and rapid method.  The present study compared the efficacy of comet assay in assessing DNA damage in buccal cells over peripheral blood leucocytes (PBLs) in oral potentially malignant and malignant disorders. Methods: The study included fifty five patients each of Leukoplakia, Oral Submucous Fibrosis (OSMF) and OSCC along with fifty five healthy individuals as control. Buccal epithelial cells were collected from all the selected subjects. DNA damage was evaluated bymeasuring the mean tail length (µm). Results: A significantly increased mean tail length (µm) and higher DNA damage were found in OSCC (26.1096 + 1.84355) and there was a progressive stepwise increase in mean tail length from control(8.4982 + 0.93307) to PMD [leukoplakia (14.6105 + 0.71857); OSMF (12.5009 + 1.12694)] to OSCC.The mean tail length in different habit groups was greater than controls, though no significant difference was noted between habit groups. The mean tail length of buccal cells was significantly greater than the mean tail length of PBLs in all study groups and controls. Conclusion: Hence, use of comet assay on buccal epithelial cells can prove to be beneficiary for evaluation of DNA damage.


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Author Biographies

Garima Rawat, Dharamshila Narayana Hospital

Dharamshila Narayana Hospital, New Delhi.

Aadithya B Urs, Maulana Azad Institute of Dental Sciences

Department of Oral & Maxillofacial Pathology, Maulana Azad Institute of Dental Sciences, New Delhi, India.

Anita Chakravarti, Maulana Azad Medical College

Department of Microbiology - Maulana Azad Medical College, New Delhi, India.

Priya Kumar, Maulana Azad Institute of Dental Sciences

Department of Oral & Maxillofacial Pathology - Maulana Azad Institute of Dental Sciences, New Delhi, India.


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How to Cite
Rawat, G., Urs, A. B., Chakravarti, A., & Kumar, P. (2019). DNA damage in buccal cells in oral PMDs and malignant disorders by comet assay. Brazilian Journal of Oral Sciences, 18, e191430. https://doi.org/10.20396/bjos.v18i0.8657249