Fig. 4.

The mitogen-activated protein kinase/ERK pathway mediates the effects of laminin (LN). (A) LM05-E cells were pretreated with 10 μM PD98059 (PD), 10 μM LY294002 (LY), or vehicle (control) for 48 hours, after which mammosphere-forming capacity was assessed. (B) LM05-E cells were pre-treated with 10 μM PD98059 (PD) or vehicle (control) for 30 minutes followed by 2 μg/mL LN for 48 hours, after which the mammosphere-forming capacity was analyzed. (C) LM05-E cells were treated with 2 μg/mL LN for 5, 10, 15, and 30 minutes. Whole cell lysates were then prepared from treated LM05-E cells, resolved in 10% sodium dodecyl sulfate polyacrylamide gel electrophoresis and blotted with p-ERK and ERK antibodies. Activation of the ERK1/2 pathway was detected by LN treatment. One of at least three experiments is shown in each case (*p < 0.05, **p < 0.01).