BACKGROUND:Mesenchymal stem cel s-released factors can form a microenvironment inhibiting malignant tumor cel proliferation, and moreover, salinomycin also inhibits the growth of tumor cel s. OBJECTIVE:To explore the effect of salinomycin with umbilical cord blood mesenchymal stem cel s in breast cancer MCF-7 cel s and its action mechanism, in order to seek a new target and therapeutic strategy to treat breast cancer. METHODS:Logarithmically growing MCF-7 cells were randomly divided into control, umbilical cord blood mesenchymal stem cell group and combination group. Cells in the control group were given no treatment, while those in the other two groups were given umbilical cord blood mesenchymal stem cell suspension or umbilical cord blood mesenchymal stem cell suspension combined with salinomycin, respectively. RESULTS AND CONCLUSION:Forty-eight hours after the intervention, the proliferation and invasion of MCF-7 cel s and expression of POSTN protein in cel s were significantly reduced in the combination group compared with the other two groups. These findings indicate that the combination of umbilical cord blood mesenchymal stem cel suspension and salinomycin effectively reduces the proliferation and migration of MCF-7 cel s, and this combined use provides a new insight into the treatment of breast cancer.