Reduction of syndecan‐1 expression is associated with dysplastic oral epithelium

Abstract: Syndecans are a family of integral membrane proteoglycans that participate in cell‐matrix interactions and growth factor binding. Syndecan‐1 expression is induced during keratinocyte differentiation and reduced in squamous cell carcinomas. The purpose of this study was to examine the alteration in syndecan‐1 expression in dysplastic oral epithelium. Sixty‐six oral biopsy specimens (43 epithelial dysplasias, 3 carcinoma in situ and 20 squamous cell carcinomas) were studied using immunohistochemical methods. The normal epithelium specimens were highly positive for syndecan‐1. Fifteen of 46 dysplasias or carcinoma in situ specimens showed negative or weak staining for syndecan‐1, two of which were totally negative. Intermediate and strong staining were observed in 17 and 14 dysplasias or carcinoma in situ specimens, respectively. Thirteen (65%) squamous cell carcinomas showed negative or weak staining for syndecan‐1, seven of which were totally negative. Only three carcinomas had a strong syndecan‐1 expression. Four of the 34 patients with dysplasia who were followed up developed squamous cell carcinoma. All these dysplasias had weak or totally negative syndecan‐1 expression. The results suggest that the loss of syndecan‐1 is associated with dysplastic changes in oral epithelium.