Immunohistochemical analysis of syndecan‐1 in leukoplakia and oral submucous fibrosis

Syndecan‑1 is abundant in normal tissues and reduced in squamous cell carcinomas. Leukoplakia and oral submucous fibrosis (OSF) are oral pre‑cancerous disorders that have potential for malignant transformation. The aim of this study was to evaluate the expression of syndecan‑1 in leukoplakia and OSF and to identify its role as a reliable marker for predicting malignant changes. Expression of syndecan‑1 was examined immunohistochemically in 42 cases of oral leukoplakia with or without epithelial dysplasia, 28 cases of OSF and 10 cases of normal oral epithelia as control. Mann-Whiteny ‘U’ test was used for statistical analysis and the level of significance was fixed at P < 0.05. Intense syndecan‑1 expression was observed in nine cases with normal epithelium. Immunopositivity was lost gradually as the extent of epithelial dysplasia increased. The significant reduction in syndecan‑1 expression was observed in leukoplakia as epithelial dysplasia progressed from moderate or severe. Similarly, significant reduction was observed in staining intensities in OSF with dysplasia. The results reveal that down‑regulation of syndecan‑1 expression is associated with dysplastic changes in leukoplakia and OSF. Thus syndecan‑1 can be considered as marker for predicting malignant changes.