Fig. 9

The effects of trastuzumab on the proliferation of CHO, CHO-EGFR, CHO-K6, and CHO-HER3 cells. The cell proliferation was examined by MTT assay as described in Materials and Methods. a The effects of HER2 overexpression on the proliferation of CHO cells. Cell proliferation of both CHO parental cells and CHO-K6 cells was examined. b-e The effects of trastuzumab on the proliferation of CHO, CHO-EGFR, CHO-K6 and CHO-HER3 cells. Cell were treated with various concentration of trastuzumab as indicated for 24 and 48 h. Non treated cells were used as negative control and the cells treated with vinorelbine (VR) were used as positive controls. b CHO cells. c CHO-HER3 cells. d CHO-EGFR cells. e CHO-K6 cells. f The effects of other HER2 inhibitors on the proliferation of CHO-K6 cells. CHO-K6 cells were treated with HER2 kinase inhibitors lapatinib (Lap) and CP714724 of indicated concentration. Each value is the average of at least three experiments and the error bar is standard error. ***: p < 0.001. ****: p < 0.0001