Protein yield and signal quality using modified extraction methods. 1A: Protein concentration of lysates generated from breast cancer cell FFPE plugs (upper panel) and FFPE xenografts (lower panel) using different extraction methods is shown. 1B: Western blots for select protein markers are shown. Extracts from breast cancer cell lines incubated with or without EGF (marked “EGF” and “ctrl” respectively) were derived from FFPE or fresh preparations using different extraction methods and subjected to western blotting. 1C: Western blots using lysates from xenografts are shown. M1 = method 1; M3 = method 3; M4 = method 4; F = lysate from frozen preparation. Arrows point to low molecular weight bands attributed to protein degradation.