CCDC3 and breast cancer: Recently, our laboratory discovered novel intracellular/nuclear functions of CCDC3 in breast cancer (BrC), where CCDC3 binds to the C-termini of p53 and MDM2, thereby protecting p53 from degradation by the 26S proteasome, while p53 also upregulates CCDC3 by binding to its promoter region, hence forming a positive feedback loop between p53 and CCDC3 to prevent BrC (Li et al., 2023a; Figure 3).