Our previous studies have suggested that Hes1 increases the number of tumor initiating cells in vivo [7], in this study, we subsequently observed that injection of HCT116 with a higher Hes1 expression (LV-Hes1) subcutaneously led to larger tumors compared with injection of HCT116 with LV-con cells, but injection of SW620 with LV-shHes1 led to smaller tumors compared with injection of SW620 with LV-shcon cells (Figure 5A, 5B, 5C, 5D, 5E). This evidence concerns the gene HES1 and neoplasm.