Figure 3: Methylation status and expression of STEAP4 in HCC primary samples. Representative results of methylation status in primary HCC tissues. STEAP4 was largely methylated in tumor tissues and unmethylated in corresponding normal samples. (b) Thirty-two of 48 (66.7%) primary HCC samples showed hypermethylation of STEAP4. Only four showed methylation in the corresponding normal samples, all of which also showed methylation in the tumor tissues. Black box indicates hypermethylation; open box indicates unmethylation. (c) Expression levels of STEAP4 mRNA, divided by GAPDH levels, in normal and tumor tissues, examined by quantitative RT-PCR. Total STEAP4 expression (relative to GAPDH) was significantly lower in tumor tissues than normal samples (median STEAP4/GAPDH ratio, 0.043 vs. 0.010; p <0.001). (d) Immunohistochemical staining of HCC case. Tumor tissue was poorly-stained with steatic degeneration, whereas normal hepatocytes were stained cytoplasmically.