Objective: To investigate the expression of EZH2 in breast cancer and its clinicopathological significance.
Methods: Eighty cases of invasive breast cancer with complete clinlcpathological data and follow-up information were enrolled in the study. The expressions of ER, PR, HER-2, CK5/6, CK14, EGFR and EZH2 proteins were detected by immunohistochemistry (IHC). The relationship of EZH2 expression with molecular subtypes and prognosis of breast cancer was analyzed.
Results: In 80 cases of breast cancer, there were 49 cases of Luminal subtype, 8 cases of HER-2(+) subtype, 20 cases of Basal-like subtype and 3 cases of Normal breast-like subtype. The molecular subtypes of breast cancer were associated with menopausal status of patients. Luminal subtype had the highest overall survival rate, while the Basal-like carcinomas were associated with the lowest survival (P< 0.05). The overall EZH2-positive expression rate was 45.00% and the expression was correlated with axillary lymph node metastasis, histological grading and clinical staging of breast cancer (P < 0.05). The EZH2-positive expression rates in Luminal subtype, HER-2(+) subtype and Basal-like subtype of breast cancers were 34.6%,50.0% and 70.0%, respectively (P <0.05).
Conclusion: Positive expression of EZH2 may indicate a poor prognosis of breast cancer patients and it might be used as a novel therapeutic target for breast cancer of Basal-like subtype.