Figure 2.

Cellular localization of TMPRSS2 in normal and carcinomatous prostate tissues. Paraffin-embedded human prostate tumor tissue sections were stained by immunohistochemistry using TMPRSS2 mAb AL20 (B, C, E, and F) and mouse IgG (A and D). Positive staining for TMPRSS2 was observed as brown precipitates (diaminobenzidine), and the nuclei were counterstained with hematoxylin. The micrographs in A–C were taken from noncancerous acini portions of the prostate tumor (nonaffected) and D–F from the cancer portions. The sizes of bars are indicated in each panel. Open arrows show TMPRSS2 on the apical surface of luminal cells. Closed arrows show the difference of TMPRSS2 protein expression in nonaffected prostate tissue and carcinomatous prostate tissue.