Effect of the hsa‑microRNA 200c‑3p/ZEB1 loop in epithelial‑mesenchymal transition of ovarian cancer cells

Ovarian cancer (OC) is a disease often diagnosed at advanced stages with distant metastasis, which is characterized by the epithelial-mesenchymal transition (EMT) of cells. The aim of the present study was to analyze the target genes of <i>Homo sapiens</i> microRNA 200c-3p (hsa-miR-200c-3p) and their associated proteins, which have a role in the EMT process. The expression level of hsa-miR-200c-3p was analyzed in ovarian tissues obtained from healthy individuals (n=15) and patients with advanced epithelial OC (EOC; n=15). Zinc finger enhancer-box binding homeobox 1 (ZEB1) is one of the target genes of hsa-miR-200c-3p and was identified using <i>in silico</i> methods. The expression level of ZEB1 was analyzed in both groups. ZEB1, vimentin and E-cadherin proteins were analyzed using immunohistochemistry (IHC) in healthy and OC tissues. The expression of hsa-miR-200c-3p was significantly increased in patients with OC (P<0.01). ZEB1 expression decreased significantly in the EOC group (P<0.01). The correlation analysis indicated a strong negative correlation between hsa-miR-200c-3p and the ZEB1 gene (ρ=-0.75; P<0.01). IHC staining revealed that the higher staining intensity of ZEB1 and E-cadherin proteins were found in cancerous tissues compared with healthy ones (P<0.05). However, the intensity and extent of vimentin staining was decreased in cancerous tissues (P<0.05). The decreased expression of ZEB1 is regulated by hsa-miR-200c-3p. The downregulation of ZEB1 may cause insufficient binding to the mRNA of E-cadherin, leading to increased E-cadherin expression. The hsa-miR-200c-3p/ZEB1 loop regulates vimentin and E-cadherin expression in OC. The increased expression level of hsa-miR-200c-3p may also cause mesenchymal-to-epithelial transition in OC cells.