When the primary tumor showed Nrf2 gene mutation, the C/A or A/A genotype, or elevated Nrf2 protein expression, the response of metastases to vascular endothelial growth factor-targeting therapy was significantly worse (p = 0.0142, p = 0.0018, and p < 0.0001, respectively), and overall survival was significantly reduced (p = 0.0343, p = 0.0421, and p < 0.0001, respectively).
The role of Notch and Nrf2 related pathways in tumorigenesis is highly variable and when they are both abnormally activated they can synergistically cause neoplastic proliferation by promoting cell survival, differentiation, invasion, and metastases.
As an important anti-oxidant element, the expression of Nrf2 may be upregulated, which in turn promotes the tumor invasion and metastases in the hypoxic microenvironment.