Cytoplasmic ABCG2 and Podoplanin Expression in Oral Squamous Cell Carcinoma Correlates with Lymph Node Metastasis

The cervical lymph node metastasis of Oral Squamous Cell Carcinoma (OSCC) has been considered to be the main causes of death. The aim of our study was to clarify the expression pattern of ABCG2 and podoplanin in OSCC tissues and corresponding cervical lymph node, and evaluate the diagnostic value of ABCG2 and podoplanin in OSCC for tumorigenesis, histological stage and clinical prognosis. ABCG2 showed a mixed membranous and cytoplasmic pattern of staining in specific regions of stratum corneum and the center of well differentiated cancer nest, while only expressed in cytoplasm of poorly differentiated tumor nests. Podoplanin showed strong staining in LV endothelia, the periphery of well differentiated cancer nests, and tumor stromal fibroblasts surrounding tumor nests. The expression of ABCG2, especially cytoplasmic ABCG2, and podoplanin protein showed significantly higher tendency to lymph node metastasis (P<0.05). Meanwhile, podoplanin positive rate increased with the decreasing degree of histological differentiation (P<0.05). ABCG2 and podoplanin expression pattern is correlated with lymph node metastasis of OSCC. This result suggested that cytoplasmic ABCG2 with podoplanin have clinical potential in reliable molecule diagonsis for OSCC.