Figure 3.

Brk’s effects on drug responses are dependent on kinase function and not proliferation. MDA-MB-468 cells, stably transfected with empty vector (V) or constructs expressing either wild-type (WT) or kinase-inactive Brk (KM), were seeded and allowed to adhere overnight in 96-well plates. Cells were treated with either (A) doxorubicin (upper panel) or (B) paclitaxel (lower panel) for 72 h. Cell viability was determined by MTT assay and expressed as a percentage of the control (vehicle only) wells. The mean % survival (+/− SD) of a representative experiment is plotted; * indicates p < 0.05. (C) Whole cells lysates were analysed for Brk expression by Western blotting with β-Actin expression as a loading control. (D) Cells were seeded into 24 well plates and replicate wells counted over 10 days.