WNT1 and breast cancer: To begin to explore the anti-tumor therapeutic efficacy of the LRP6 antibodies, we treated two models of Wnt ligand-driven tumors, MMTV-Wnt1 transgenic mammary tumor allografts dependent on Wnt1 expression and Ntera-2 human teratocarinoma xenografts driven by autocrine Wnt signaling of an unknown Wnt isoform [21].