MicroRNA-16 inhibits migration and invasion via regulation of the Wnt/β-catenin signaling pathway in ovarian cancer

Abstract

As small non-coding RNA molecules, microRNAs (miRs) function in the regulation of tumorigenesis. Proliferation in ovarian cancer is considered to be associated with miR-16; however, the role of miR-16 in the migration and invasion of ovarian cancer cells remains unclear. The results of the present study demonstrated that miR-16 expression is downregulated in the ovarian cancer SKOV3 and OVCAR3 cell lines compared with that in normal ovarian epithelial cells (OECs). miR-16 overexpression inhibited the proliferation, migration and invasion of SKOV3 and OVCAR3 cells, and decreased the expression of matrix metallopeptidase (MMP)2 and MMP9. Additionally, miR-16 upregulated the expression of cadherin 1, an intercellular adhesion molecule, and downregulated the expression of some mesenchymal markers, including snail family transcriptional repressor 2, snail family transcriptional repressor 1, Vimentin, twist family BHLH transcription factor 1 and cadherin 2 in SKOV3 and OVCAR3 cells. Furthermore, it was indicated that miR-16 overexpression in SKOV3 and OVCAR3 cells resulted in a significant increase in anti-glycogen synthase kinase 3 β expression and a decrease in the expression of Wnt family member 3A, β-catenin, MYC proto-oncogene, BHLH transcription factor and cyclin D1 compared with the NC group. The results of the present study indicated that miR-16 exerts a suppressive effect on cell migration and invasion in ovarian cancer in vitro, through inactivation of the Wnt/β-catenin signaling pathway. The data suggest that miR-16 may be a potential therapeutic agent for the treatment and prevention of ovarian cancer.

Keywords: Wnt family member 3A; invasion; microRNA-16; migration; ovarian cancer.

Figure 1.

miR-16 expression in SKOV3 and OVCAR3 ovarian cancer cells compared with normal OEC cells. *P<0.05 compared with OEC. OEC, normal ovarian epithelial cells, miR, microRNA.

Figure 2.

miR-16 inhibits the proliferation of ovarian cancer cells. (A) The inhibition efficiency of miR-16 mimics with regard to the expression of miR-16 in SKOV3 cells. (B) The proliferation of ovarian cancer in SKOV3 cells between 0 and 72 h. (C) The inhibition efficiency of miR-16 mimics with regard to the expression of miR-16 in OVCAR3 cells. (D) The proliferation of ovarian cancer in OVCAR3 cells between 0 and 72 h. *P<0.05 compared with the NC. OD, optical density; miR, microRNA; NC, negative control.

Figure 3.

miR-16 inhibits the migration and invasion of ovarian cancer cells. miR-16 inhibited the migration of (A) SKOV3 cells and (B) OVCAR3 cells. scratch assay: magnification, ×40. miR-16 suppressed the invasion of (C) SKOV3 and (D) OVCAR3 cells in a Transwell chamber invasion assay. Transwell chamber invasion assay: magnification, ×100. *P<0.05 compared with the NC. miR, microRNA; NC, negative control.

Figure 4.

Effect of miR-16 on the expression level of MMP proteins in SKOV3 and OVCAR3 cells. (A) The expression of MMP9 and MMP2 in SKOV3 and OVCAR3 cells. Quantification of protein bands in (B) SKOV3 and (C) OVCAR3 cells (n=5). *P<0.05 compared with the NC. MMP, matrix metallopeptidase; miR, microRNA; NC, negative control.

Figure 5.

Effect of miR-16 on the expression level of EMT-associated proteins in SKOV3 and OVCAR3 cells. (A) Expression of EMT-associated proteins, including Twist, Vimentin, SNAIL, Slug, E-CAD and N-CAD in SKOV3 and OVCAR3 cells. Quantification of expression levels of EMT-associated proteins in (B) SKOV3 and (C) OVCAR3 cells *P<0.05 compared with the NC. Slug, Snail family transcriptional repressor 2; SNAIL, snail family transcriptional repressor 1; Twist, twist family BHLH transcription factor 1, E-CAD, cadherin 1; N-CAD, cadherin 2; miR, microRNA; NC, negative control; EMT, epithelial-mesenchymal transition.

Figure 6.

Effect of miR-16 on the expression of Wnt/β-catenin signaling pathway-associated proteins in SKOV3 and OVCAR3 cells. (A) Expression of Wnt/β-catenin signaling pathway components, including β-catenin, Gsk3β, Wnt3a, c-MYC and cyclin D1 in SKOV3 and OVCAR3 cells. Quantification of expression levels of Wnt/β-catenin signaling pathway components in (B) SKOV3 and (C) OVCAR3 cells. *P<0.05 compared with the NC. Gsk3β, glycogen synthase kinase 3 beta; c-MYC, MYC proto-oncogene, BHLH transcription factor; Wnt3a, Wnt family member 3A; miR, microRNA; NC, negative control.