Immunohistochemical study of glucose transporter protein expression in oral lichen planus

Oral lichen planus (OLP) is a chronic mucocutaneous inflammatory disease that is somewhat frequently manifested in various clinical forms: reticular OLP (ROLP) and erosive OLP (EOLP), and some cases are associated with dysplasia. Higher risk of malignant transformation has been linked to dysplastic alterations in OLP. Glucose transporter protein (GLUT1) is a transmembrane glycoprotein associated with increased glucose metabolism and proliferation of cells. This study's objective was to analyze and compare the expression patterns of GLUT1 in EOLP, ROLP, and lichen planus-related dysplasia in an attempt to acquire improved knowledge of the molecular pathways that underlie the etiology and advancement of OLP.

In this retrospective study, analysis of GLUT1 expression was done in 32 samples of OLP (16 for ROLP, 10 for EOLP, and 6 for OLP with dysplasia) with immunohistochemistry. Statistical analysis was performed using Pearson's Chi-square and F-tests, with significance set at P < 0.05. The immune GLUT-1 expression was evaluated semi-quantitatively and qualitatively at ×100 magnification.

The mean percentage of GLUT1-positive cells in ROLP (16.53 ± 11.72) was lower than that in EOLP and OLP with dysplasia. Among the three groups, there was a significant difference in terms of staining intensity, intracellular location, and extent of GLUT1 immunoexpression within the epithelium layers (0.000, 0.034, and 0.006, respectively).

GLUT1 overexpression reflects increased glycolytic activity of proliferating cells in response to hypoxia and high energy requirements in EOLP and OLP-related dysplasia. GLUT1 expression may predict the malignant potential of OLP toward oral squamous cell carcinoma.