Notably, when we stained subcutaneous tumor tissue sections for HLA-I, which can distinguish human tumor cells from mouse cells, we found that although it exerted a negative role in cell invasion in vitro, GFI1 expression caused a shift from the expansive to the invasive phenotype in all studied subcutaneous tumors (Figure 4B and Supplemental Figure 11B). This evidence concerns the gene GFI1 and neoplasm.