A computational screen revealed that NF-κB was located in miR-21 gene transcriptional element, and the transcriptional regulation NF-κB was located in miR-21 gene transcriptional element, and transcriptional regulation of miR-21 by NF-κB have been reported in many human cancers, such as breast cancer, glioma, and gastric cancer [53-55]. This evidence concerns the gene NFKB1 and breast cancer.