The clinicopathological and prognostic significance of CD24, CD44, CD133, ALDH1 expressions in invasive ductal carcinoma of the breast: CD44/CD24 expression in breast cancer.

BACKGROUND: Recently, there are several studies about cancer stem cells (CSC), indicating that they are the cells that initiate the tumor, provide progression, metastasis and responsible for the aggressive tumor behavior.

MATERIALS AND METHODS: The purpose of this study is to investigate the expressions of CD24, CD44, their different combinations, ALDH1 and CD133 in invasive ductal carcinoma. Their relationships with clinicopathologic parameters, such as tumor grade, lymphovascular invasion, tumor size, axillary lymph node involvement, stage, hormone receptors, HER2 expression, basal like tumors, triple negative status and prognosis were also investigated. Tissue microarray method was used to investigate ımmunohistochemical CD24, CD44, ALDH1 and CD133 expressions in 105 invasive ductal carcinoma cases.

RESULTS: CD133 expression was significantly associated with tumor size (p=0.023) and stage (p=0.009). CD133 expression was decreased in tumors with larger tumor size, higher stage and lymphovascular invasion. CD133 expression was positively correlated with CD44 (r=0.212, p=0.032) and CD44(+)/CD24(+) (r=0.202, p=0.040) expressions. CD44, CD24 and ALDH1 expressions showed no significant relationship and correlation with clinicopathologic features. There was a significant relationship (p=0.048) between CD44(+)/CD24(-/low) phenotype and basal like tumors. EGFR expression was positively correlated with CD44(+)/CD24(-/low) phenotype (r=0.211, p=0.036).

CONCLUSIONS: Basal like tumors are enriched for CSCs with CD44(+)/CD24(-/low) phenotype. CD133 can detect a different population of CSC in breast carcinoma.