CD44 and neoplasm: After subsetting 7 days KPY tumor organoids into CD44-high (enriched for Hmga2-high cells) and CD44-low (enriched for SPC-high cells) populations, we cultured those cells into organoids with (co-culture) or without (mono-culture) lung mesenchymal cells to compare the organoid forming efficiency (OFE) (Fig. 4D).