Overexpression of GPR39 in ESCC. GPR39 was frequently overexpressed in primary ESCCs (A) and ESCC cell lines (B) detected by RT-PCR. For primary ESCCs, expression of GPR39 in tumor tissues (T) was compared with their paired non-tumorous tissues (N). Normal esophageal tissue was used as a normal control. 18S rRNA was used as an internal control. (C) Representative of GPR39 expression in a pair of ESCC (right) and adjacent normal tissue (left) detected by immunostaining with anti-GPR39 antibody (brown). The slide was counterstained with hematoxylin (original magnification × 200).