Molecular markers of epithelial-to-mesenchymal transition in triple-negative breast cancer

Abstract

Objective To investigate the molecular alterations in breast cancer samples using epithelial-to-mesenchymal transition (EMT) markers such as E-cadherin, vimentin, epidermal growth factor receptor (EGFR), platelet-derived growth factor (PDGF)-D, and nuclear factor-κB (NF-κB) to reveal their roles in the EMT and breast cancer progression. Methods In 57 cases of invasive ductal breast carcinoma, the expression of E-cadherin, vimentin, EGFR, NF-κB, and PDGF-D was detected using immunohistochemistry. Tumors were categorized into three groups: A [estrogen receptor (ER)+ , and/or progesterone receptor (PR)+ , human epidermal growth factor receptor-2 (Her-2)/neu-], B (ER+ , and/or PR+ , Her-2/neu+ ), and C (triple-negative: ER-, PR-, and Her-2/neu-). Immunostained tissue biopsies were observed under a microscope, evaluated and scored using intensity (0, + , + + , and + + + ) and percentage of positive cells, and data were statistically analyzed. Results Membranous E-cadherin was positive in all 57 cases (100%), whereas cytoplasmic E-cadherin was predominantly positive in groups B and C as compared with group A (21%, 7%, and 0%, respectively). All cases in group A were negative for vimentin and EGFR. There was statistically increased expression of vimentin, EGFR (P<0.01), and NF-κB (P<0.05) in triple-negative cases when compared with groups A and B. Conclusion Vimentin, EGFR, and NF-κB were significantly increased in triple-negative breast cancer, which is consistent with the invasiveness of these tumors. Key words: Triple-negative breast cancer; Epithelial-to-mesenchymal transition; E-cadherin; Vimentin; Epidermal growth factor receptor; Platelet-derived growth factor-D