KRT20 and neoplasm: Consistent with these findings, we found that Thbs1+ cells in mouse tumours largely coincide with the cells expressing the widely accepted Wnt target genes Axin2 (Figure 5—figure supplement 1D) and Lgr5 (Barker et al., 2009; Figure 5A and B, Figure 5—figure supplement 1E), while they do not express the differentiation marker Keratin 20 (Figure 5—figure supplement 1F).