Expression and significance of c-myc and CD24 in colorectal cancer

Abstract

Objective To determine the expression of c-myc and CD24 in colorectal carcinoma, colo-rectal polyp and normal mucosa, and to explore the role and correlation of them in the carcinogenesis of colorectal carcinoma. Methods The expression of c-myc and CD24 in colorectal carcinoma (n=60), colorectal adenomatous polyp (n=45), colorectal hyperplastic polyp (n=15) and the adjacent non-cancerous tissue (n=30) was observed by immunohistochemical assay. Results The positive rate of c-myc in colorectal carcinoma were 73.3%, significantly higher than that in colorectal adenomatous polyp 44.4% (χ2=9.016 8, P<0.01), colorectal hyperplastic polyp 13.3% (χ2=18.215 9, P<0.01) and adjacent non-cancerous tissue 6.7% (χ2=25.133 0, P<0.01); the positive rate of CD24 in colorectal carcinoma was 76.7%, significantly higher than that in colorectal hyperplastic polyp 6.7% (χ2=25.133 0, P<0.01) and adjacent non-cancerous tissue 3.3% (χ2=43.107 4, P<0.01). c-myc expression in colon cancer was significantly correlated with cancer site (χ2=8.352 3, P<0.01), lymph node metastasis (χ2=4.275 1, P<0.05), differentiation (χ2=4.115 3, P<0.05) and TNM stage (χ2=5.739 9, P<0.05). CD24 expression in colon cancer was significantly correlated with cancer size (χ2=9.333 6, P<0.01), lymph node metastasis (χ2=7.693 0, P<0.01), differentiation (χ2=5.870 0, P<0.05) and TNM stage (χ2=4.498 7, P<0.05). There was a positive correlation relationship between CD24 and c-myc in colorectal carcinoma tissue (χ2=10.824 9, r=0.39, P<0.05). Conclusion The expression of c-myc and CD24 are high in colorectal cancer, having a significant correlation with some of the clinicaopathological features. c-myc is likely to act as a downstream target gene of CD24 signaling pathway, whose expression is probably regulated by CD24 in colorectal carcinoma tissue. Key words: Colorectal neoplasms; Immunohistochemistry; Genes, myc; CD24