Expression of SOX9 Is Related to Prognosis in Patients with Oesophageal Squamous Cell Carcinoma

Sex-determining region Y-box 9 (SOX9) is an important transcription factor for the development and differentiation of cells and their organization. In the present study, the clinical significance of SOX9 expression in oesophageal squamous cell carcinoma was examined. SOX9 expression in surgical specimens of primary tumours were immunohistochemically investigated in 175 patients with oesophageal squamous cell carcinomas. SOX9 was expressed (moderately or strongly) in 62.9% of samples. Expression of SOX9 was significantly positively correlated with depth of invasion, advanced stage, lymphatic and venous invasion, and poor prognosis. Univariate analysis showed that depth of invasion, lymph node metastasis, distant metastasis, stage, lymphatic invasion, venous invasion, and SOX9 expression were prognostic factors. Multivariate analysis indicated that depth of invasion and stage were independent prognostic factors, but SOX9 expression was not. SOX9 expression is related to prognosis in patients with oesophageal squamous cell carcinoma, although it is not an independent prognostic factor.