Increased osteopontin expression is associated with progression from vulvar precancerous lesions to vulvar squamous cell carcinoma

Abstract

Vulvar squamous cell carcinoma (VSCC) contributes to about 3-5% of all gynecological cancers. Vulvar intraepithelial neoplasia (VIN) and vulvar lichen sclerosus (VLS) are regarded as precancerous lesions. Early detection and treatment of precancerous lesions may prevent development of VSCC. Osteopontin (OPN) has been shown to be involved in many physiological and pathological processes, such as tumor progression, by promoting cancer cell invasion and metastasis. As a result of these findings, OPN has been described as a potential marker for tumor progression in some malignancies. In this study, we investigated the expression of OPN in vulvar tissue specimens and compared its expression between different histopathological grades. In the present study, the expression patterns of OPN in 80 paraffin-embedded tissue specimens, including 25 VSCC samples, 21 VIN lesions and 21 VLS, in addition to 13 normal vulvar samples, were examined by the immunohistochemical method and chromogenic in situ hybridization. The intensity of OPN expression steadily increased according to the pathological grades. In addition, OPN staining was found in the extracellular matrix in VSCC. Expression levels of OPN increased from VLS and VIN to VSCC, and steadily increased with the pathological stage of VSCC. Our results suggest that OPN may be associated with the progression of VSCC.