Purpose: To determine the potential involvement of ANXA1 in oral squamous-cell carcinoma (OSCC), we evaluated the ANXA1 protein expression in oral premalignant lesions (OPLs) and OSCCs and correlated the results with clinicopathologic variables.
Methods: Matched normal and tumour specimens of 44 primary OSCCs and 28 OPLs were analyzed for ANXA1 subcellular localization and protein expression level by immunohistochemistry (IHC). Correlations between ANXA1-IHC staining scores of OSCCs and clinicopathologic features were evaluated by Fisher's exact test.
Results: Markedly down-regulation of ANXA1 protein expression was identified on the plasma membrane of epithelial cells in OSCCs (P < 0.001) and OPLs (P = 0.001) compared with normal counterparts. Moreover, loss of plasma membranous ANXA1 expression was significantly correlated with the poorly differentiated status of OSCC cells (P = 0.012).
Conclusions: Our findings suggest that loss of ANXA1 is frequent and early event during oral carcinogenesis and that ANXA1 could contribute to maintaining epithelial differentiation in OSCC.