Expression data from ERBB2 over-expression and EGF stimulation in MCF10A cells The cells were transduced with retroviruses encoding vector control (pBabe) or pBabe-ErbB2. After infection cells were switched to assay medium supplemented with only 2% horse serum and no EGF. For EGF stimulation, cells transduced with empty vector were treated with EGF at 50 ng/ml for 2 hours before harvesting.