Figure 1: Downregulation of HER2 expression by TPL in oral, breast, and ovarian cancer cell lines. (a) KB and OEC-M1 human oral cancer cell lines; (b) BT-474, MCF-7/HER, and MCF-7 human breast cancer cell lines; and (c) SKOV-3, OVCAR-3, and TOV-21G human ovarian cancer cell lines were treated with 50 nM of TPL or vehicle (0.01% DMSO) control for 24 h. Cell lysates were immunoblotted with antibodies specific for HER2/neu or actin. SKOV-3 cells were treated with the indicated dose of TPL for 72 h. Morphological variations were recorded (d), and growth inhibition by TPL was quantified (e). The experiment was repeated three times.