Aberrantly elevated redox sensing factor Nrf2 promotes cancer stem cell survival via enhanced transcriptional regulation of ABCG2 and Bcl-2/Bmi-1 genes.

The presence of cancer stem cells in cervical cancer stem cells (CSCs) is important in the prevention of therapy failure and tumor recurrence. Upregulation of transcriptional regulation of redox sensing factor Nrf2 leads to the overexpression of drug efflux proteins such as ABCG2 in cancer stem cells and thus results in cancer treatment failure and cancer relapse. In the present study, we purified approximately 3.1% of cervical CSCs, which exhibited aberrant upregulation of Nrf2 in conjunction with an elevated transcriptional regulation of ABCG2, Bcl-2 and Bmi-1. Consequently, CSCs possess prolonged cell survival, infinite cell proliferation and highly resistant apoptosis. Following silencing of the function of Nrf2 the cervical CSCs became more sensitive to DNA targeting drugs and apoptosis. Our results suggested that Nrf2-mediated drug and apoptosis resistance are important in cancer therapies and tumor recurrence. Therefore, designing anticancer drugs targeting Nrf2 may be crucial to prevent CSC-mediated tumorigenesis.