MAP2K7 and glioblastoma: To reveal which signaling pathways may be responsible for the S1P-mediated migration of LN18 GBM cells, we blocked known S1P-induced signaling pathways by specific inhibitors such as PD98059 (MEK/ERK inhibitor), SB202190 (p38 inhibitor), WP1066 (STAT3 inhibitor) and LY294002 (PI3K/AKT1 inhibitor).