Figure 1.

EGFR protein and gene status in colorectal carcinomas. Immunohistochemical expression of EGFR protein designated as discontinuous, basolateral or continuous membrane staining of different intensity: (a) week, (b) moderate and (c) strong immunostainining. Chromosome 7 copy number was analyzed in tumor cells using fluorescence in situ hybridization (FISH) with an α-satellite DNA probe for chromosome 7 (centromere 7, red signal; EGFR gene, green signal); (d) tumor nuclei without abnormality; (e) tumor cells showed polysomy with a greater number of red and green signals than in normal cells; and (f) tumor cells with amplification (a-c, magnification ×200, d-f magnification ×100).