CXCL12 and bone cancer: To examine whether the production of CXCL12 is required for the activation of astrocytes, we intrathecally injected an astrocyte metabolic inhibitor fluorocitrate[34] (1 nmol/10 μl) into the bone cancer rats once daily for three consecutive days (from day 8 to 10 after TCI), then detected the GFAP immunoreactivity and CXCL12 protein level after the last injection.