Fig. 4

No significant changes of p-HER3, HER3, and p-FOXO3a were observed between DMSO- and lapatinib-treated tumors derived from SKBR3-pool2 or BT474-HR20 cells. The tumors derived from either SKBR3-pool2 (A) or BT474-HR20 (B) cells were formalin-fixed and paraffin-embedded (FFPE) and sectioned into five-micron-thick slides. The FFPE slides were analyzed with IHC staining assays for p-HER3 (Y1289), HER3, or p-FOXO3a (Ser253) following the procedures described in the materials and methods. Two individuals independently evaluated the IHC staining. The levels of p-HER3, HER3, and p-FOXO3a showed no apparent differences between control and lapatinib-treated groups