Early in 1999, Guttridge et al revealed that NF-κB controls cell growth and differentiation through transcriptionally regulating cyclin D1 using both skeletal muscle differentiation models and normal diploid fibroblasts.252 More recent studies focusing on cancer showed that PAK upregulation enhanced cyclin D1 through NF-κB in breast cancer, consequently coordinating cell-cycle movement.253 Mutations in driver genes are also shown to have a close relationship with the NF-κB pathway in cancer cells. This evidence concerns the gene CCND1 and breast cancer.