GSK3B and neoplasm: Furthermore, the treatment of Group 3 and -4 xenograft with CHIR99021 (a GSK-3β inhibitor) improved survival by activating β-catenin, increasing axin2 mRNA and downregulating Sox2 and Bmil; L807mts, another GSK-3β inhibitor, can induce Wnt/β-catenin signaling in Group 3 and -4 medulloblastoma xenografts, decreasing tumor burden and increasing survival with respect to control xenografts [215].