CAT-1 protein expression in colorectal cancer tissues by tissue <t>microarray.</t> The CRC tissue microarray (TMA) was stained with CAT-1 antibody and visualized using a DAB staining kit. The density of CAT-1 expression in the normal colon, well differentiated CRC, and poorly differentiated CRC samples from TMA was compared. The images were taken at 40× magnification. 