SNAI1 and cancer: To investigate the function of SNAIL in different cancer types in vivo, we created a latent Snail allele silenced by a lox-stop-lox (LSL) cassette as a knock-in (KI) at the mouse Rosa26 locus (LSL-R26Snail/+ mouse line, termed SnailKI/+; Supplementary Fig. S1a–c).