Figure 1.

Immunohistochemistry of human primary tumors. (A and B) ALDH1A1⁺ cells were located singularly, in groups and more centrally within cell nests. (C) Tumor expressing ALDH1A1 completely. (D-F) CD44, EGFR and Ki-67 were expressed marginally to generally within the cell nests. (G and H) ALDH1A1 expression pattern only partly overlapped with CD44 or EGFR. (I) The rate of Ki-67⁺ cells was independent from ALDH1A1 expression. Magnification, ×200; hem counterstaining. ALDH1A1, aldehyde dehydrogenase 1 family, member A1; CD44, hyaluronan receptor cluster of differentiation 44; EGFR, epidermal growth factor receptor; hem, hematoxylin.