Fig. 5.

Co-treatment with GEM and T-DM1 synergistically inhibited the proliferation of MIA PaCa-2 cells. a MIA PaCa-2 cells were treated with GEM (0, 30, 100 or 300 ng/ml) for 2 h, washed with PBS and incubated in medium containing T-DM1 (0, 10 or 30 μg/ml) for 96 h. Then, the cells were detached by trypsin-EDTA treatment, and identical numbers of cells that were not stained with trypan blue were seeded into 96-well plates and incubated for 96 h. Cell growth was examined by spectrophotometry. *P < 0.05, **P < 0.01 vs. samples untreated with T-DM1 at each GEM concentration. The same experiment was performed twice, and similar results were obtained. b GEM-treated (100 ng/ml) MIA PaCa-2 cells were incubated with trastuzumab (0, 10, 30 or 100 μg/ml) in the presence of T-DM1 (30 μg/ml) for 96 h, and identical numbers of cells not stained with trypan blue were seeded into 96-well plates. After a 96-h incubation, cell growth was examined by spectrophotometry using the counting reagent SF. *P < 0.01 vs. samples treated with GEM, T-DM1 and 100 μg/ml of Trastuzumab. c Capan-1 cells were treated in the same way as MIA PaCa-2 cells, as described in (a). Cell growth was examined by spectrophotometry. *P < 0.05, **P < 0.01 vs. samples not treated with T-DM1 at each GEM concentration