CXCR4 and breast cancer: For example, in glioma, activation of NF-κB signaling was crucial for the promotion of glioma cell invasion and migration [45, 46]; in addition, a study by Helbig and colleagues has noted that expression of chemokine receptor CXCR4 was induced by activation of NF-κB signaling, which promoted the migration and metastasis of breast cancer cells [47].