Loss of MTSS1 Expression is an Independent Prognostic Factor for Hilar Cholangiocarcinoma

Metastasis suppressor 1 (MTSS1) is a novel metastasis suppressor gene in a variety of cancers. This study aimed to detect MTSS1 expression in normal and cancerous tissue specimens from Chinese patients with hilarcholangiocarcinoma to determine the association with clinicopathological parameters and survival. Tissue microarrays containing normal and tumor specimens were constructed using paraffin blocks from 61 patients for immunohistochemical analysis of MTSS1 expression. A subgroup of these tissues was verified by Western blot analysis. MTSS1 protein was expressed in 24 of 61 cases (39.3 %) of tumor tissues, compared to that in 22 of 26 (84.6 %) of non-neoplastic bile duct epithelium and in 26 of 26 (100 %) of adjacent normal liver cells. Loss of MTSS1 expression was associated with lymph node metastases of cholangiocelluarcarcinoma and tumorcellde-differentiation.MTSS1 expression inversely associated with tumor recurrence and overall survival of the patients by univariate and multivariate analyses. MTSS1 expression was significantly decreased in human hilarcholangiocarcinoma and lost MTSS1 expression was associated with pooroverall survival and tumor recurrences in cholangiocarcinoma patients. Thus, MTSS1 expression represents an independent predictor for tumor recurrence and overall survival in patients with cholangiocarcinoma.