In contrast to Meis1 expression in normal epidermis (Fig. 1), we found that Meis1-EGFP was not co-expressed with β4 integrin, CD34, or K15 in the tumor basal layers, where epidermal cancer stem cells are thought to reside in papillomas (Fig. 7G–7O). The gene discussed is KRT15; the disease is papilloma.