Aim: The present study aimed to determine the role of SRY (sex-determining region Y)—box 2 (SOX2) as a potential marker of stemness and pluripotency and to compare its association with the normal oral mucosa (NOM), different grades of oral epithelial dysplasia (OED), and oral squamous cell carcinoma (OSCC).
Materials and methods: A total of 70 study samples, including 30 cases of OED (10 each of mild, moderate, and severe dysplasia), 30 cases of OSCC [10 each of well-, moderate-, and poorly differentiated (WD, MD, and PD)], and 10 NOM samples were immunohistochemically stained to evaluate SOX2 association. Quantitative analysis was based on the percentage of positive cells with a scoring of 0–5 (0%, 1–10%, 11–30%, 31–50%, 51–80%, and >80%), and qualitative evaluation was based on the intensity of staining grading from 0–3 (negative, weak, moderate, and strong). Differences in staining intensity were evaluated using the Kruskal–Wallis test. Statistical comparison of positive cells among three groups was performed using one-way analysis of variance and a pairwise comparison within groups using Tukey analysis.
Results: SOX2 expression was more prominent in OSCC than OED and weakest in normal mucosa. A significant increase in SOX2 expression was observed from mild to severe dysplasia, whereas the expression decreased from WDOSCC to PDOSCC.
Conclusion: In conformity with the present study, SOX2 expression is seen to be upregulated in higher grades of OED and early OSCC. Thus, highlighting its role in identifying the potential lesions at an early stage.
Clinical significance: Identification of cancer stem cells (CSCs) using biomarkers may help in the early detection of tumor development. SOX2 showing evidence of expressing these cells can be utilized as a definitive biomarker.
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