Immunohistochemical analysis of FAK expression in breast cancer TMA samples. FAK expression was detected by immunohistochemical staining with FAK 4.47 monoclonal antibody of TMA samples with triplicate tissue cores per tumor stained. The slides were scored by a board-certified pathologist using the following scoring system that measured intensity: (0, none; 1+, weak; 2+, moderate; 3+, strong) (A) and extent of staining (0, no positive staining; 1, one core has positive staining score; 2, two cores have positive staining; and three cores have positive staining (B). The staining score was calculated by adding the average intensity and extent of staining and the core ranged from 0 to 6. Upper panel: different intensity of staining from 0 to 3+ is shown in breast samples. The intensity from 0 to 3 is shown on A and extent from 1 to 3 is shown on B panel.