Evaluation of Glucose Transporter 1 and Hypoxia Inducible Factor 1α in Oral Epithelial Dysplasia and Oral Squamous Cell Carcinoma: An Immunohistochemical Cross- Sectional Study

<title>Abstract</title> <p>Background and Purpose Oral squamous cell carcinoma (OSCC) is frequently preceded by oral potentially malignant disorders exhibiting oral epithelial dysplasia (OED). Hypoxia and altered glucose metabolism are important features of tumor progression. Glucose transporter 1 (GLUT1) and hypoxia inducible factor 1 alpha (HIF-1α) are associated with cellular adaptation to hypoxia and increased glycolytic activity. Hence purpose of this study is to evaluate the expression of GLUT1 and HIF-1α in oral epithelial dysplasia and oral squamous cell carcinoma. Materials and Methods An in-vitro immunohistochemical cross-sectional study was carried out using paraffin embedded tissue sections diagnosed as normal oral mucosa, oral epithelial dysplasia and OSCC. Total of 64 samples were included and divided into Group I: normal oral mucosa (n = 10), Group II: oral epithelial dysplasia (n = 27), and Group III: OSCC (n = 27). Immunohistochemical evaluation of GLUT1 and HIF-1α expression was performed quantitatively and qualitatively using staining intensity and distribution. Statistical analysis was performed using Kruskal Wallis test and Mann Whitney U test with p &lt; 0.05 considered statistically significant. Results Both GLUT1 and HIF-1α expression showed progressive increase from normal oral mucosa to OED and OSCC. Increased expression was noted with increasing histological grades of dysplasia and carcinoma. Significant intergroup differences were observed, suggesting a positive prognostic association between hypoxia-induced metabolic alteration and tumor progression. Conclusion The present study demonstrated that GLUT1 and HIF-1α play a consistent role in tumor microenvironment alteration in both oral premalignant and malignant lesions. Their increased expression is associated with increased disease severity and malignant transformation. Co-expression of these proteins may serve as prognostic biomarkers in OED and OSCC.</p>