Fig. 3

Expression of NCX1, NCX2, and NCX3 in normal and tumor tissues of CC by HE and IHC stainings (×200). a HE staining for normal colonic mucosa. The structure of normal colonic mucosa. The glands were arranged in order. The nuclei of epithelial cells and stromal cells were clear. b In the normal colon, NCX1 was highly expressed in the cell membrane of normal colonic glandular epithelial cells and stromal cells in the mucosa, and the closer to the intestinal cavity, the stronger the staining was. c NCX2 was moderately expressed in stromal cells and glandular epithelium. d The expression of NCX3 mainly in stromal cells and submucosa. e HE staining for colonic malignant glands. The glands showed disorganized malignant growth. The nucleus was large and hyperchromatic with vacuoles. f NCX1 was moderately expressed in malignant glands. g The positive expression of NCX2 was noticeably decreased compared to that in normal tissues. h The staining intensity of the NCX3 protein in tumor tissue was very low by IHC. i The integral optical density (IOD) is represented by a histogram. (tumor: colonic malignant tumor; normal: normal colonic tissue; black arrows refer to glands, white arrows refer to stromal cells; one-way ANOVA; *p < 0.05 and **p < 0.01, compared with NCX1-tumor; ^#p < 0.05, compared with NCX2-tumor; ^@p < 0.05, compared with NCX3-tumor)