Distribution and phenotype of colorectal cancer cells with high NOTCH activity. (A) Representative immunostaining for NICD in primary colon cancer tissue. Right panel shows higher magnification of area boxed in the left panel. Arrowheads indicate tumor cells at the tumor edge, and arrows indicate tumor cells toward the tumor center; open arrowhead indicates an endothelial cell. (B, D, F, and H) Double immune fluorescence for indicated proteins in representative colon cancer tissues. Arrowheads indicate tumor cells at the tumor edge, and arrows indicate tumor cells toward the tumor center. Open arrow indicates endothelial cells at the tumor edge. (C, E, G, and I) Quantification of co–immune fluorescence signals. Relative fluorescence intensities (% RFI) for indicated proteins in tumor cells with high (upper quartile) and low (lower quartile) NICD staining intensity are shown. Data are derived from n ≥ 500 tumor cells in n = 10 different colorectal cancer cases. Error bars indicate mean ± SD. **, P < 0.01; ***, P < 0.001 by t test. Bars: 200 µm (A, left); 20 µm (A, right); 50 µm (B, D, F, and H).