CXCR4 and central nervous system cancer: AHR' antagonist quercetin inhibited U87MG cells' invasion via downregulating phospholipase D1, omeprazole inhibited breast cancer metastasis in a mouse model and cancer patients via downregulation of the AHR-CXCR4 signaling pathway [14], indirubin inhibited glioma invasion in a mouse model via inhibition of GSK3beta [17], and AHR-agonist 3-MC inhibited HUVEC migration by reducing FAK activity.