CXXC4 is zinc finger protein that binds directly to the PDZ domain of DVL1, a protein involved in the Wnt signaling pathway, through its C-terminal region. CXXC4 interaction with DVL1 competes with DVL1-AXIN binding, although the affinity of DVL1 for CXXC4 is lower than that for AXIN. In mouse fibroblasts, CXXC4 suppressed Wnt3a induction of beta-catenin and inhibited Wnt3a-dependent TCF4 activation, suggesting that CXXC4 acts as a negative regulator of the Wnt signaling pathway and functions between DVL and beta-catenin. Recent reports suggest that decreased CXXC4 expression is associated with kidney cancer metastasis, cell proliferation, reduced apoptosis in response to cancer drugs, and upregulation of genes involved with proliferation, invasion and cell survival, suggesting that CXXC4 plays a critical role in tumor progression in kidney cancer.
CXXC finger 4; CXXC-type zinc finger protein 4; Dvl-binding protein IDAX (inhibition of the Dvl and Axin complex); inhibition of the Dvl and axin complex protein