To confirm the role of Zic2 proteins in colon cancer, we performed immunohistochemical (IHC) staining of 180 colon cancer samples via a tissue microarray (Fig. 1d–f, cohort I) and found a markedly increased protein level of Zic2 in colon cancer tissues compared with adjacent colon normal tissues (P < 0.0001, Fig. 1d, e). This evidence concerns the gene ZIC2 and colonic neoplasm.