Initial TGFβ receptor activation in breast or skin cancer results in transcriptional activation of SNAI1, combined with sumoylation of SNAIL at K234 fostering SMAD/SNAIL complex formation that promotes EMT (Hoot et al, 2008; Vincent et al, 2009; Gudey et al, 2017) (Fig 4B). This evidence concerns the gene SNAI1 and skin cancer.