Abstract

BACKGROUND
CD24 was originally described as a B cell-specific marker, however its aberrant expression in various solid tumors has recently been reported. Our objective was to determine the pattern and extent of the CD24 expression in colorectal cancer and its related lesions, and to clarify its correlation with clinico-pathological parameters and especially those associated with patients' prognoses.
METHODS
A total of 307 colorectal cancers and the related lesions (150 carcinomas, 30 high-grade adenomas, 49 low-grade adenomas, 41 hyperplastic polyps, and 37 normal colorectal epithelia) were immunohistochemically analyzed by treating CD24 monoclonal antibody onto tissue embedded paraffin blocks.
RESULTS
CD24 expression was very rarely observed in the normal epithelia, hyperplastic polyps, and low-grade adenomas; however, in high-grade adenomas, the CD24 expression was shown to be mildly increased in the cytoplasm (13.3%). In carcinomas, the CD24 expression was increased substantially in both the membrane (38.0%) and the cytoplasm (44.7%). The expression of CD24 in the membrane was positively correlated with tumor size (p<0.01). The CD24 expression in the cytoplasm was positively correlated with several unfavorable parameters, including a larger tumor size (p<0.01), a higher tumor grade (p<0.01), a higher rate of tumor invasion (p<0.05), and a higher pTNM stage (p<0.05).
CONCLUSION
High levels of CD24 expression in the membrane and cytoplasm were characteristic in colorectal cancer, and the cytoplasmic CD24 expression was correlated with several unfavorable clinical parameters.

• Keywords: CD24;Colorectal neoplasm;Immunohistochemistry