EGFR and breast cancer: To evaluate the potential roles of the CREB, ERK1/2, and EGFR signaling in LPA-induced expression of pro-fibrotic growth factors, SAE BC were treated with 1 μg/ml LPA for 3 h in the absence or presence of signaling pathway inhibitors and either collected immediately for RNA analysis or washed and placed in basal medium for 24 h when proteins in the cell culture medium were assessed.