MUC1 and breast cancer: On the other hand, MUC1-C was shown to bind to NF-κB/p65 and led recruitment of MUC1-C/NF-κB complexes to the promoters of NF-κB target genes, such as Bcl-xL and the promoter of the MUC1 gene itself, in breast cancer and leukemia cells suggesting MUC1 was a direct activator of NF-κB/p6547.