miR-132 inhibits colorectal cancer invasion and metastasis via directly targeting ZEB2

Figure 1 miR-132 is significantly down-regulated in colorectal cancer cell lines and tissues with distant metastases. A: Relative expression level of miR-132 in colorectal cancer (CRC) cell lines and the normal colonic cell NCM460 (^aP < 0.05); B: Relative expression level of miR-132 in CRC tissues with distant metastases (n = 32) and CRC tissues without metastases (n = 30) (^bP < 0.01).

Figure 2 miR-132 predicts disease-free survival in colorectal cancer patients. The Kaplan-Meier curve of disease-free survival in patients with high miR-132 expression (n = 31) and low miR-132 expression (n = 31) (P < 0.01).

Figure 3 miR-132 inhibits colorectal cancer cell invasion. A: Ectopic expression of miR-132 inhibits cell invasion in LoVo cells (^aP < 0.05); B: Knockdown of miR-132 promotes cell invasion in HCT116 cells (^aP < 0.05).

Figure 4 miR-132 regulates epithelial-mesenchymal transition in colorectal cancer cells. A: Ectopic expression of miR-132 leads to a cobblestone-shaped epithelial-like form in LoVo cells; B: Knockdown of miR-132 leads to spindle-shaped mesenchymal characteristics in HCT116 cells; C, D: Overexpression of miR-132 increased the protein levels of epithelial markers (E-cadherin and α-catenin) but decreased the expression of mesenchymal markers (vimentin and fibronectin) in LoVo cells, whereas knockdown of miR-132 resulted in decreased levels of epithelial markers (E-cadherin and α-catenin) and increased levels of mesenchymal markers (vimentin and fibronectin) in HCT116 cells.

Figure 5 ZEB2 is a direct target of miR-132 in colorectal cancer cells. A: Ectopic expression of miR-132 reduces the ZEB2 mRNA levels in LoVo and SW620 cells (^aP < 0.05); B: Ectopic expression of miR-132 decreases the ZEB2 protein levels in LoVo and SW620 cells; C: Co-transfection of pcDNA-miR-132 and pGL3-wt-EB2 reduced the luciferase activity in 293T cells (^aP < 0.05).