This signaling pathway is also known to be important during bone-directed migration of GPR54-positive breast cancer cells (113) and kisspeptin can indirectly regulate sdf1/cxcr4 through desensitization of cxcr4 by preventing rise in intracellular Ca2+ levels after sdf1 stimulation (114, 115). This evidence concerns the gene CXCR4 and breast cancer.