Correlation between epithelial-mesenchymal transition related markers and poor clinical outcome of triple-negative breast cancer

Abstract

Objective To investigate the expression of epithelial-mesenchymal transition (EMT) related molecular markers (vimentin, smooth muscle actin, osteonectin, N-cadherin, and E-cadherin loss) and EMT inducer zinc-finger E-box binding homeobox 1 (ZEB1) in triple-negative breast cancer (TNBC) samples and inquire the correlation between their expression and clinicopathological features of the tumors. Methods We analyzed immunohistochemical expression of EMT-related markers mentioned above in 173 TNBC samples and correlation between their expression with clinicopathological features of the tumors, including clinical outcome. Results The expression levels of vimentin were more frequent in basal-like TNBC (87/154, 56.5%) than in non-basal-like TNBC (3/17, 17.6%). The ZEB1 expression was correlated only with the expression of smooth muscle actin (P=0.002). The survival analyses revealed that vimentin (P=0.515), smooth muscle actin (P=0.739), osteonectin (P=0.094), E-cadherin (P=0.925) and N-cadherin (P=0.509) were not associated with patients’ clinical outcomes. However, the ZEB1 expression was found to be an independent prognostic factor for poor disease-free survival. Conclusion These findings indicate that the expression of EMT-related markers in TNBC can be a signature of a certain subgroup of TNBC. Key words: Triple-negative breast cancer; Epithelial-mesenchymal transition; Vimentin; Smooth muscle actin; Osteonectin; N-cadherin; E-cadherin