Cepharanthine suppresses metastatic potential of human cholangiocarcinoma cell lines

Cholangiocarcinoma (CCA) is a highly metastatic tumor with poor responses to traditional chemotherapeutic agents. We have focused on new drugs which can exert effects either alone or in combination with available agents for a better treatment of CCA and recently reported efficacy of cepharanthine (CEP), a natural biscoclaurine alkaloid extract with anti-proliferative activity against human CCA cell lines. CEP treatment effectively suppressed tumor growth in CCA-inoculated mice without serious side-effects and also increased cell apoptosis in primary histocultures of CCA patient tissues, suggesting therapeutic potential of CEP against human CCA. In the present study, we further showed anti-metastatic effects of CEP on migration and invasion of human CCA cell lines. CEP at 10 μg/mL effectively suppressed migration activity of KKU-M213 and KKU-M214 as shown by wound healing and Boyden chamber assays. Similar suppressive effects were observed in invasion assays. The molecular mechanism underlying CEP actions on cell motility and invasion could be shown to involve suppression of ICAM-1 and MMP-2. Our results suggest CEP as a potential therapeutic agent for treating metastatic CCA.