The Cancer Stem Cell Concept in Progression of Head and Neck Cancer

Figure 2

ALDH1 expression in HNSCC tissues: (a) nonmetastatic primary tumor with negative ALDH1 expression, (b) metastatic primary tumor with positive ALDH1 expression, and (c) corresponding lymph node metastases. (Magnification: 400x).

(a)

(b)

(c)