Immunohistochemical analysis of Metadherin in proliferative and cancerous breast tissue

BACKGROUND: Metadherin (MTDH) has been reported to be associated with cancer progression in various types of human cancers including breast cancer. Whether MTDH contributes to carcinogenesis of breast cancer is still unknown. In the present study, we investigated the expression of MTDH in normal, UDH (usual ductal hyperplasia), ADH (atypical ductal hyperplasia), DCIS (ductal carcinoma in situ) and invasive cancer to explore the possible role of MTDH for breast cancer carcinogenesis. METHODS: Immunohistochemistry was employed on paraffin sections of surgical removed breast samples. RESULTS: The immunohistochemical results showed almost no staining in normal tissue, moderate staining in ADH and UDH, intense MTDH stains in DCIS and cancer. Statistical analysis demonstrated significant different MTDH expression between proliferative and cancerous breast lesions (p < 0.001). MTDH was positively correlated with the histological differentiation of DCIS (p = 0.028). In breast cancer, statistical analysis revealed a significant correlation between MTDH expression with patients' age (p = 0.042), ER status (p = 0.018) and p53 status (p = 0.001). We also examined the effect of MTDH on cell proliferation in DCIS and cancer, and we found that MTDH overexpression was significantly correlated with high Ki67 index (p = 0.008 and p = 0.036, respectively). CONCLUSIONS: MTDH overexpression could be identified in proliferative breast lesions and may contribute to breast cancer progression.