Of note, tumor heterogeneity can result from a single cell, as lentiviral transduction studies show that both ESA+CD44− (i.e. NTG) and ESA+CD44+CD166+ (i.e. CoCSC) cells have identical lentiviral insertion sites (Figure 6D inset), but only CoCSC are able to propagate tumors. This evidence concerns the gene EPCAM and neoplasm.