Inhibitory effect of Coptidis Rhizoma and berberine on the proliferation of human esophageal cancer cell lines

Our previous study demonstrated that the herbal medicine, Oren-to, had anti tumor effects on esophageal:cancer cells (ECCs) in vitro. The purpose of th is study was to examine which of the seven constituents of Oren-to had anti tumor effects on esophageal cancer cells. MTT assay showed that, of the sev en constituents, only the aqueous extract of Coptidis Rhizoma had potent in hibitory effect on the proliferation of two types of ECC lines, YES-3 and Y ES-4. In addition, the proliferation of all six types of ECC lines (YES-1 t o YES-6) was inhibited in a dose-dependent manner (P < 0.001 for all), when co-cultured at each concentration of Coptidis Rhizoma for 72 h. The ID50 o f Coptidis Rhizoma for YES-1 to YES-6 was 2.2 mu g/ml, 3.0 mu g/ml, 0.25 mu g/ml, 2.8 mu g/ml, 2.5 mu g/ml, and 0.5 mu g/ml, respectively. berberine, one of protoberberine components of Coptidis Rhizoma, showed potent antitum or effects on all six types of ECC lines as well as Coptidis Rhizoma. In ad dition, the ID50 of berberine showed a positive correlation with that of Co ptidis Rhizoma in six types of ECC lines examined (r(2) = 0.763, P = 0.023) . Cell cycle analysis of Coptidis Rhizoma-treated cancer cells showed the a ccumulation of cells in the G(0)/G(1) phase and relative decrease of the S phase. These results support the possibility that the use of Coptidis Rhizo ma containing abundant berberine may be useful as one of alternative therap ies for esophageal cancers. (C) 2000 Elsevier Science Ireland Ltd. All righ ts reserved.