Abstract:

Objective

To explore whether the down-regulation of ezrin can affect the invasion and metastasis of human breast cancer MDA-MB-231 cells via MMP-9,Src/β-catenin pathways.

Methods

After the lentivirus were infected into MDA-MB-231 cells, the cells were divided into experimental groups (231-sh1 and 231-sh2) and negative control group (231-NC). The interference efficiency of ezrin was tested by Western blot and immunofluorescence assay. The abilities of migration and invasion were evaluated by Transwell assays after ezrin down-regulation. The expressions of matrix metalloproteinase-9(MMP-9) and the related proteins of Src/β-catenin pathway were also detected by Western blot. The means between groups was compared using oneway variance analysis and Post hoc test (LSD).

Results

Western blot results showed that after lentivirus being infected into MDA-MB-231 cells, the expression of ezrin protein in groups 231-sh1 and 231-sh2 was significantly lower than that in group 231-NC (231-NC:1.0083±0.0629;231-sh1:0.3833±0.0326;231-sh2:0.3342±0.0306;all P＜0.050). The immunofluorescence assay showed the same change(231-NC:30.103±2.243;231-sh1:17.227±1.801;231-sh2:14.857±0.394;all P＜0.050). In migration experiment, the number of cells passing through the Transwell membrance in 231-sh1 and 231-sh2 was significantly lower than that in 231-NC(231-NC:940.67±80.507;231-sh1:459.67±51.549;231-sh2:402.00±52.460, all P ＜0.050). The invasion experiment showed the same change(231-NC:157.33±9.713;231-sh1:96.00±14.731;231-sh2:73.67±13.503, all P＜0.050). Compared with 231-NC, the expressions of MMP-9, Src, P-Src, β-catenin and P-β-catenin in 231-sh1 and 231-sh2 were significantly decreased (all P ＜0.050).

Conclusions

The down-regulation of ezrin expression may inhibit the abilities of migration and invasion in MDA-MB-231 cells via the phosphorylation of MMP-9, src and β-catenin.

Key words: Breast neoplasms, ezrin, Invasion, Metastasis