We examined tumor tissues and adjacent liver tissues from 100 HCC patients for CtBP2 expression by immunohistochemistry. We found that CtBP2 staining was strongest in the tumor cell cytoplasm, while nuclear staining was observed in relatively few cells (Figure 1A). CtBP2 expression was elevated in tumor cells when compared to benign tissues in 60% of the HCC tumors examined. Mann-Whitney U analysis demonstrated that CtBP2 expression was significantly higher in HCC tissues when compared to adjacent liver tissues (p < 0.001, Figure 1B). Clinical association analysis using the Spearman rank test demonstrated that CtBP2 overexpression in HCC tissues was positively correlated with tumor size ( p = 0.039), venous infiltration ( p = 0.003), Edmondson-Steiner Classification ( p < 0.001) and the Tumor Node Metastasis (TNM) stage ( p = 0.018).
