Comparative analysis of Ki-67, α-SMA, and MMP-9 expression in oral submucous fibrosis and oral leukoplakia with/without dysplasia: Insights into malignant transformation mechanisms

Background

The present study aimed to comparatively analyze the immunoexpression of Ki-67, Alpha Smooth Muscle Actin (α-SMA), and Matrix Metalloproteinase-9 (MMP-9) between Oral Leukoplakia (OL) and Oral Submucous Fibrosis (OSMF), both with and without dysplasia. The objective was to determine the potential role of these biomarkers in the diagnosis and prognostication of oral potentially malignant disorders (OPMDs) and their potential as targets for interventions.

Materials and methods

Immunohistochemical staining for Ki-67, α-SMA, and MMP-9 was performed on seventy formalin-fixed paraffin-embedded tissue blocks, comprising normal buccal mucosa (n = 10), OSMF (n = 30), and OL (n = 30) with 15 cases each of dysplasia and non-dysplasia. The expression of these markers was comparatively evaluated in OSMF and OL, with and without dysplasia.

Results

The immunoexpression of Ki-67, MMP-9, and α-SMA was found to be significantly higher (p < 0.001) in OSMF compared to OL for the respective dysplastic counterparts. Additionally, OSMF with dysplasia exhibited a significantly higher expression (p < 0.001) of these markers compared to OSMF without dysplasia.

Conclusions

The present study reports differences in cell proliferation rates, myofibroblast and MMP-9 expression between OSMF and OL. The higher expression of these markers in OSMF with dysplasia suggests accelerated disease progression and enhanced potential for transformation into oral squamous cell carcinoma (OSCC). These findings highlight variations in the tissue microenvironment of OPMDs, influencing their biological behaviour and prognosis.