Increased TFF1 trefoil protein expression in Opisthorchis viverrini-associated cholangiocarcinoma is important for invasive promotion

Aims: Cholangiocarcinoma (CCA) is a poor prognosis cancer that presents with metastatic disease. This cancer expresses MUC5AC, a mucin which normally co-expresses with trefoil factor family 1 (TFF1) protein. TFF1 is a signalling protein that can activate epithelial cell invasion and has been considered as a metastasis stimulating agent. The aim of this study was to determine the co-expression of TFF1 and MUC5AC in CCA tissues and examine the activity of TFF1 for stimulating the invasive property of CCA cell lines. Methods: In this study, TFF1 and MUC5AC were detected in CCA tissues by using immunohistochemistry. The correlations of both proteins expression with clinical data were analyzed. The activity of TFF1 was investigated using an in vitro invasion assay with established CCA cell lines KKU-100 and KKU-M213. Results: We demonstrated a high level of expression of TFF1 in 91.80% of CCA that is associated with a high level of co-expression with MUC5AC in 80.33% of cases. In vitro invasion assay showed that both cell lines have similar responses to TFF1 that could act as both a chemokinetic and chemotactic agent. The dose-response curves were bell-shaped. Conclusion: TFF1 showed co-expression with MUC5AC in CCA tissues and invasive stimulating activity in vitro. These results may indicate a role for TFF1 in promoting tumor invasion in CCA.