PRDX2 expression is closely associated with CD133+CD44+ CCSCs in colon cancer. (A) Left panel: Representative IHC images of CD133(+)/CD44(+) colon cancer tissues showing strong PRDX2 expression compared to CD133(-)/CD44(-) colon cancer tissues with weak PRDX2 expression. Right panel: Comparison of the proportions of PRDX2 expression in CD133(+)/CD44(+) colon cancer tissues (n = 9) and CD133(-)/CD44(-) colon cancer tissues (n = 10). Statistical analysis: Fisher’s exact test, **p < 0.01. (B) Quantitation of PRDX2, CD44 and CD133 mRNA expression in 40 paired human colon tumor tissues (T) and matched adjacent noncancerous tissues (ANT) by real-time reverse transcription PCR analysis. Relative values were normalized to GAPDH. Statistical analysis: Paired t-test, ****p < 0.0001. (C) PRDX2 levels are correlated with CD133 and CD44 expression at the mRNA level. The data are presented as the fold changes in cancer specimens compared to matched adjacent noncancerous tissues. Statistical analysis: Nonparametric Spearman correlation analysis (R value) was performed. (D) Immunofluorescence analysis of PRDX2 expression and the coexpression of CD133 and CD44 in spheroid CD133+CD44+ CCSCs and adherent CD133-CD44- cells isolated from HCT116 and HT29 cell lines, respectively.