Protein Expression Profile Of Glycitein-Treated Cholangiocarcinoma Kku-M213 Cell Line

Cholangiocarcinoma (CCA), a malignant epithelial neoplasm originating from the biliary tract, is a serious health problem of northeastern Thailand. Currently, there are no effective drugs against this cancer. Among isoflavones daidzein, genistein and glycitein, and equol, a derivative of daidzein, glycitein demonstrated the highest inhibitory effect of on the proliferation of human cholangiocarcinoma cell line KKU-M213 with an IC50 (50% inhibitory concentration) of 27 mu M. As a first step towards understanding its mechanism of action, differential protein expression profiling of glycitein-treated and -untreated KKU-M123 cells were conducted using mass spectrometry (MS). Two hundred and fifteen proteins were expressed in both test cells; 129 and 114 proteins only in glycitein-treated and untreated cells respectively; 39 up-regulated and 14 proteins down-regulated in treated compared to untreated cells. The majority of up-regulated proteins were classified as those involved in metabolic and cellular processes, while that of down-regulated proteins also included transport, cell cycle, developmental process, and cellular component organization. These relative fold differences obtained from MS analysis were confirmed by western blotting of two representative proteins. These results provide baseline proteomics data that should be of assistance in identification of isoflavones anti-proliferative mechanisms against CCA and help guide future discovery and development of chemotherapeutic agents from natural products.