Expression and significance of bone sialoprotein(BSP) in esophageal squamous cell carcinoma

Abstract

To investigate the roll of bone sialoprotein (BSP), a secreted glycoprotein, found in mineralized tissues in the development and progression of human esophageal squamous cell carcimoma (ESCC), and explore its association with clinicopathological characteristics and five-year survival of the patients. The expression of BSP was determined in 211 primary ESCC tumors and their paired nontumorous tissues using tissue-array, RT-PCR and immunohistochemistry. Primary ESCC tissues showed a significantly higher expression rate of BSP mRNA than their paired nontumorous tissues (93.8% vs. 16.6%, P < 0.001), the same with BSP protein (56.9% vs. 31.3%, P < 0.001). The expression rate of BSP protein was correlated to lymph node metastasis and TNM stage (P < 0.05). The 5-year survival rate of BSP protein-positive ESCC patients was significantly lower than that of BSP protein-negative ESCC patients (P < 0.05). Multivariate analysis showed that tumor differentiation, TNM staging and BSP protein expression were independent factors affecting the prognosis of ESCC patients (P < 0.05). The abnormal expression of BSP may play a significant role in the malignant progression and prognosis of ESCC, and BSP might be a marker reflecting the biologial behavior of ESCC.