Evaluation of oxidant–antioxidant status in tissue samples in oral cancer: A case control study

Abstract

Background: Imbalances between the oxidant–antioxidant status have been implicated in the

pathogenesis of several diseases, including cancer. The aim of this study was to evaluate the extent

of lipid peroxidation and antioxidants in the tissue samples of oral squamous cell carcinoma (OSCC)

patients of different clinical stages in comparison with the healthy controls.

Materials and Methods: A case‑control study was designed with 20 new histopathologically

proven oral carcinoma patients and an equal number of age, sex, and tobacco chewing habit

matched healthy subjects. Their tissue samples were subjected to evaluation of lipid peroxidation

product and antioxidant enzymes, namely, superoxide dismutase (SOD), catalase (CAT), reduced

glutathione (GSH), and glutathione peroxidase (GPx) using spectrophotometric methods. The

data are expressed as mean ± standard deviation. The statistical comparisons between the study

groups were performed by independent Student’s unpaired t‑test and one‑way analysis of variance.

Post‑hoc analysis was performed for within study group comparisons. Karl Pearson correlation was

performed for the biochemical parameters within the group and between the groups. For statistically

significant correlations, simple linear regression was performed using SPSS (α=0.05).

Results: Significant reduction in lipid peroxidation (P < 0.001) SOD and CAT (P < 0.001) was

observed in the tissue of OSCC patients as compared with the healthy controls. On the other

hand, reduced GSH and GPx were significantly increased in tumor samples.

Conclusion: Reduced lipid peroxidation and increased activity of reduced GSH and GPx provides

the suitable environment for the local growth and invasion of the tumor and metastasis in the

later stages. Among the antioxidant enzymes, GSH reductase appears to have a profound role in

carcinogenesis and thus it can be considered as potential prognostic marker.

Key Words: Antioxidants, lipid peroxidation, oral cancer, oxidative stress