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In Figs 1e and 2j, k of this paper, the colour keys are incorrect. In Fig. 1e, the blue bars indicate TOPFLASH and the purple bars indicate FOPFLASH. The description of the results in the text is correct. In Fig. 2j and k, the green fluorescence indicates P-cadherin (Pcad) and E-cadherin (Ecad), respectively, and the red fluorescence indicates the marker for the basement membrane, laminin (lam).