Epithelial–mesenchymal transitions (EMTs) are essential manifestations of epithelial cell plasticity during tumor progression. Transforming growth factor-β(TGF-β) modulates epithelial plasticity in tumor physiological contexts by inducing EMT, which is associated with the altered expression of genes. In the present study, we used DNA micro-array analysis to search for differentially expressed genes in the TGF-β1 induced gallbladder carcinoma cell line (GBC-SD cells), as compared with normal GBC-SD cells. We identified 225 differentially expressed genes, including 144 that were over-expressed and 81 that were under-expressed in the TGF-β1 induced GBC-SD cells. NT5E (CD73) is the most increased gene, while the Fc fragment of the IgG binding protein (FcGBP) is the most decreased gene. The expression patterns of these two genes in gallbladder adenocarcinoma and chronic cholecystitis tissue were consistent with the micro-array data. Immunochemistry and clinicopathological results showed that the expression of NT5E and FcGBP in gallbladder adenocarcinoma is an independent marker for evaluation of the disease progression, clinical biological behaviors and prognosis. The data from the current study indicate that differential NT5E and FcGBP expressions could be further evaluated as biomarkers for predicting survival of patients with gallbladder cancer and that NT5E and FcGBP could be promising targets in the control of gallbladder cancer progression.Electronic supplementary materialThe online version of this article (doi:10.1007/s00441-013-1752-1) contains supplementary material, which is available to authorized users.

Cofilin-1 (CFL1) and Arp3 expression in 46 squamous cell and adenosquamous carcinomas (SC/ASCs) and 80 adenocarcinomas (ACs) were measured by using immunohistochemistry. Positive CFL1 and Arp3 expression were significantly associated with large tumor size, high TNM stage, lymph node metastasis, and decreased overall survival in both SC/ASC and AC patients (p < .001). Multivariate Cox regression analysis showed that positive CFL1 and Arp3 expression are independent poor-prognostic factors for both SC/ASC and AC patients. Our study suggested that positive CFL1 and Arp3 expression are closely related to tumor progression, metastasis, and poor prognosis of gallbladder cancer.

Gallbladder cancer (GBC) is a rare but highly aggressive cancer for which no well-accepted prognostic biomarkers have been identified. Thymus cell antigen 1 (Thy1), also known as cluster of differentiation (CD)90, and integrin α6 (ITGA6), also known as CD49f, are important molecules in cancer and putative markers of various stem cell types. However, their role in GBC remains to be elucidated. In the present study, Thy1 and ITGA6 expression status in clinical GBC samples, which comprised squamous cell/adenosquamous carcinoma (SC/ASC) and adenocarcinoma (AC) subtypes, was investigated. The associations between Thy1 and ITGA6 expression and clinical parameters and survival rate were analyzed separately. The THY1 and ITGA6 messenger RNA levels were significantly higher in both SC/ASC and AC tissues than in adjacent non-tumor tissues (all P<0.001). These results were subsequently confirmed by immunohistochemical analyses. Overexpression of Thy1 and ITGA6 was correlated with poor differentiation, large tumor size, lymph node metastasis and great invasiveness in SC/ASC (Thy1, P=0.045, P=0.005, P=0.003 and P=0.009, respectively, and ITGA6, P=0.029, P=0.011, P=0.009 and P=0.004, respectively) and AC (Thy1, P=0.027, P<0.001, P=0.003 and P 0.004, respectively, and ITGA6, P=0.002, P=0.003, P=0.006 and P=0.006, respectively). Both Thy1 and ITGA6 were expressed at higher levels in AC with advanced tumor-node-metastasis stage (TNM) than in AC with low TNM stage (P=0.001 and P=0.018, respectively). In addition, patients with elevated Thy1 or ITGA6 expression had shorter overall survival than those with negative Thy1 or ITGA6 expression. Multivariate Cox regression analysis demonstrated that Thy1 (SC/ASC, P=0.001 and AC, P=0.005) and ITGA6 (both P=0.003) were independent predictors of poor prognosis in both SC/ASC and AC patients. In conclusion, Thy1 and ITGA6 could be clinical prognostic markers for GBC.