Human umbilical cord matrix-derived stem cells expressing interferon-β gene inhibit breast cancer cells via apoptosis

Human umbilical cord mesenchymal stem cells (hUCMSCs) derived from the umbilical cord matrix have been reported to be used as anti-tumor gene carrier for attenuation of tumor growth, which extends the half-life and lowers the unexpected cytotoxicity of the gene in vivo. Interferon-β (IFNβ) is known to possess robust anti-tumor effects on different types of cancer cell lines in vitro. The present study was aimed to investigate the anti-tumor effect of IFNβ gene-transfected hUCMSCs (IFNβ-hUCMSCs) on breast cancer cells with emphasis on triple negative breast carcinoma. Our findings revealed that the co-culture of IFNβ-hUCMSCs with the human triple negative breast carcinoma cell lines MDA-MB-231 or Hs578T significantly inhibited growth of both carcinoma cells. In addition, the culture medium conditioned by these cells also significantly suppressed the growth and induced apoptosis of both carcinoma cells. Further investigation showed that the suppressed growth and the apoptosis induced by co-culture of IFNβ-hUCMSCs or conditioned medium were abolished by pretreating anti-IFNβ neutralizing antibody. These findings indicate that IFNβ-hUCMSCs triggered cell death of breast carcinoma cells through IFN-β production, thereby induced apoptosis and suppressed tumor cell growth. In conclusion, we demonstrated that IFNβ-hUCMSCs inhibited the growth of breast cancer cells through apoptosis. With potent anti-cancer activity, it represents as an anti-cancer cytotherapeutic modality against breast cancer.