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 Homo sapiens 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 in silico 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.