In order to generate stable gain-of-function in vitro models over-expressing a full-length NMU cDNA, the basal-like Hs578T and the luminal-like, HER2-positive SKBR3 cell line were chosen as adequate in vitro tumor models showing marginal levels of NMU mRNA (Figure 4A) and no detectable NMU protein (Figure 4C). This evidence concerns the gene ERBB2 and neoplasm.