KRT20 and neoplasm: Since LGR5+ and KRT20+ cells appear to reside within distinct tumour niches [298], it is plausible that depletion of the LGR5+ population exposes differentiated KRT20+ cells to aberrant instructive signals that incite their dedifferentiation and acquisition of CSC traits, analogous to the reversion of multiple intestinal cell types to an Lgr5+ state during injury-induced regeneration [9,20,26].