Many colon cancers showed increased nuclear β-catenin and FRA1 expression in tumor cells located at the infiltrative tumor edge, whereas CK20 and GLUT1 were most strongly expressed in the tumor center, often close to necrotic areas, suggesting a polarity with differentiation gradients directed from the tumor edge toward the tumor center (Fig. 1a, b and Supplementary Fig. 1). The gene discussed is SLC2A1; the disease is colonic neoplasm.