Prognostic Significance of CD24 in Clear Cell Renal Cell Carcinoma

The role of cancer stem cells in the initiation and progression of cancer has become a well-studied area of emerging research, and stem cells with different surface markers have been identified in various types of cancer. CD24 is a membrane protein that acts as the ligand for P-selectin and has been defined as a stem cell marker of colonic cancer. The immunohistochemical expression of CD24 is associated with worse patient outcomes in small cell lung cancer, hepatocellular carcinoma, breast cancer, and colon cancer. In this study, we used immunohistochemistry to determine CD24 expression in clear cell, papillary and chromophobe renal cell carcinoma and investigated its relationship with other clinicopathological parameters and prognosis. A total of 108 cases of clear cell, 12 papillary and 13 choromophobe renal cell carcinoma were examined. Clinicopathological features including age, gender, vascular invasion, tumor necrosis, and T stage were recorded. Clinical stage and overall survival and disease-free survival times were recorded. The immunohistochemical expression of CD24 was classified as low or high based on the percentage and intensity of positive staining. CD24 expression was associated with both tumor grade and recurrence rates. The survival analysis revealed that patients with high CD24 expression exhibited significantly lower overall and disease-free survival. Increased expression of CD24 is related to the prognosis of clear cell renal cell carcinoma. This is the first study identifying a strong association between CD24 expression levels and survival. Thus, CD24 expression may aid in predicting prognosis in clear cell renal cell carcinoma.