Objective  To investigate the effect of simvastatin on expression of pluripotent markers Oct3/4, Nanog, and Sox-2 in human breast cancer MCF-7 cells.

  Methods  Quantitative reverse transcription–polymerase chain reaction (qRT-PCR), immunofluorescent staining, flow cytometry, and Western blot were used to detect the expression of pluripotency markers Oct3/4, Nanog, and Sox-2 in human breast cancer MCF-7 cells treated with different doses of simvastatin.

  Results  qRT–PCR revealed the more significant inhibition of gene expressions of Oct3/4, Nanog, and Sox-2 in human breast cancer MCF-7 cells when subjected to high doses of simvastatin (10, 50, and 100 μmol/L) compared with the control group (P < 0.05). By contrast, no significant difference was observed between the expressions of low-dose simvastatin treatment (1 μmol/L) and control (P>0.05). The inhibitory effect of simvastatin on the gene expressions of Oct3/4 and Nanog was more significantly apparent at 50 and 100 μmol/L dosages than at 10 μmol/L (P < 0.05). By contrast, no significant difference in the inhibitory expression of Sox-2 was observed among the three high-dose treatments (P>0.05).Between the two higher-dose treatments (50 and 100 μmol/L), no significant difference in the inhibitory expressions of Oct3/4, Nanog, and Sox-2 in MCF-7 cells was found. Meanwhile, in the 10 μmol/L simvastatin treatment, immunoflurescent staining showed a marked reduction in the protein expression of all three pluripotent markers in MCF-7 cells, and flow cytometry demonstrated a decrease of Oct3/4-, Nanog-, and Sox-2-positive cells (P < 0.05). Western blot further revealed that the protein expression of Oct3/4, Nanog, and Sox-2 in MCF-7 cells was significantly declined by the same simvastatin dose (P < 0.05).

  Conclusion  Simvastatin can inhibit the expression of pluripotent markers Oct3/4, Nanog, and Sox-2 in human breast cancer MCF-7 cells, proving the anti-cancer properties of simvastatin.