SSEA-5 and L1CAM immunoreactivity in human tumors. Tumor arrays were immunostained for both SSEA-5 (red) and L1CAM (green) as described in Section 2. For each tumor type, L1CAM, SSEA-5, and a merged image are shown. Note that the primitive tumors (embryonal carcinoma and neuroectodermal tumor) show predominantly SSEA-5 immunoreactivity (and little L1CAM immunoreactivity), while retinoblastoma shows more L1CAM immunoreactivity. The urothelial carcinoma showed immunoreactivity for both markers, with overlap in the merged image. Scale bar = 20 microns.