Immunohistochemical detection of CHD5 protein in normal tissues and primary tumors of the human breast. (A) Validation of CHD5 antibody by detecting CHD5 protein in CHD5-positive T-47D cells but not in CHD5-negative ZR-75-1 cells by IHC with the CHD5 antibody. Rabbit preimmune IgG was used as the negative control. (B, C) Normal breast tissue stained with rabbit anti-CHD5 antibody (B) or preimmune rabbit IgG (C, negative control). Arrows indicate cells that are positive for CHD5 staining. (D-G) Representative breast cancers showing no CHD5 protein expression (D) and low (E), medium (F) and high (G) levels of CHD5 expression.