Orthotopic primary tumors and MRLs were generated, as above, from H2B-eGFP-labeled HER2/neu-Prim1 or Wnt1-Prim1 tumor cells, and osmotic pumps were employed to deliver bromodeoxyuridine (BrdU) for 2 weeks prior to sacrifice. This evidence concerns the gene WNT1 and neoplasm.