However, we did not detect such ROR1–cortactin complexes in lysates prepared from breast-cancer–PDX cells cultured overnight in serum-free media unless they were treated with exogenous Wnt5a (Fig. 1f, g), suggesting that the endogenous Wnt5a was limiting and insufficient to maintain ROR1–cortactin complexes in vitro. This evidence concerns the gene WNT5A and breast carcinoma.