Heme Oxygenase-1 Inhibits Tumor Metastasis Mediated by Notch1 Pathway in Murine Mammary Carcinoma

Heme oxygenase-1 (HO-1) plays an important role in the progression of several malignancies including breast cancer. However, its role in breast cancer metastasis is still ambiguous. In this study, we observed the effect of HO-1 on mouse mammary carcinoma metastasis using the in vivo tumor metastasis model. Our results revealed that overexpression of HO-1 strongly inhibits the lung metastasis of 4T1 cells. In in vitro analysis, associated indices for epithelial–mesenchymal transition (EMT), migration, and proliferation of 4T1 cells were evaluated. The results show that HO-1 inhibits EMT, migration, and proliferation of 4T1 cells. In addition, the Notch1/Slug pathway is found to mediate an antimetastasis role of HO-1 in mouse mammary carcinoma. In conclusion, since HO-1/Notch1/Slug axis plays an important role in breast cancer metastasis, induction of HO-1 could be used as a potential therapeutic strategy for breast cancer treatment.