Metastasis suppressor 1 acts as a tumor suppressor by inhibiting epithelial-to-mesenchymal transition in triple-negative breast cancer.

OBJECTIVE

This study aimed to analyze the function of metastasis suppressor 1 () in triple negative breast cancer (TNBC).

METHODS

expression in 30 TNBC and paracancerous tissues was measured by quantitative reverse transcriptase polymerase chain reaction. The prognostic value of was assessed by Kaplan-Meier analysis followed by the log-rank test. MCF7 cells were transfected with si-, while MDA-MB-231 cells were transfected with pcDNA3.1-. Cell proliferation assay and transwell assay were performed to investigate the effects of on the biological behavior of breast cancer cells. Immunofluorescence and western blot were used to detect the influence of on epithelial-mesenchymal transition (EMT) markers.

RESULTS

expression was significantly lower in TNBC tissues compared with that in paracancerous tissues (0.012 vs. 0.370; = 0.006). A lower expression level was also found in tumor tissues of patients with lymph node metastasis ( = 0.002) or tumor node metastasis stage ( = 0.010). Patients with low expression of (⩽ 0.009) had shorter disease-free survival (47.4 vs. 56.0 months; = 0.012). The knockdown of in MCF7 cells inhibited cell proliferation, enhanced cell migration and invasion capacities, decreased the E-cadherin level, and increased the vimentin level, whereas overexpression of in MDA-MB-231 cells had the opposite effects ( < 0.05).

CONCLUSIONS

Our findings demonstrated that regulates proliferation, invasion, migration, and EMT in TNBC, and that decreased is associated with shorter disease-free survival.