Figure 1.

WNT activation impairs tumor growth in Group 3 and 4 medulloblastoma (MB). Endogenous WNT-active cells were isolated from Group 3 and 4 MB samples after generating stable Group 3 and 4 MB brain tumor-initiating cell (BTIC) lines containing the WNT TCF reporter, TGP. TGP+ cells (WNT active, GFP+) and TGP- cells (WNT inactive, GFP-) were isolated using flow cytometric cell sorting. TGP+ xenografts generated smaller tumors with a prolonged survival compared to TGP- xenografts. In a separate experiment, Group 2, 3, and 4 xenografts were treated with small molecule WNT agonist, L807mts, which resulted in impaired tumor formation and survival advantage in treated mice compared to controls. (GFP: green fluorescent protein, TCF: T-cell factor)