NF-κB binds to the inhibitor of NF-κΒ (IκΒ) in the cytoplasm, promotes the expression of inflammatory mediators linked to BC, such as interleukins 8, 5, and 20 (IL-8, IL-5, and IL-20, respectively) [67], and increases the transcription of metalloproteinases 2 and 9 (MMP2 and MMP9, respectively), which are responsible for promoting invasion and metastasis of bladder tumors [68]. This evidence concerns the gene CXCL8 and breast cancer.