Nevertheless, it is yet to be proven whether GD55 could effectively eliminate liver CSCs (such as the sphere cells) in the same way as we have reported for liver cancer cells, and our present results also showed that PLC/PRF/5 sphere cells acquired a little more expression level of GP73 (Figure 4A and Supplementary Figure S4A), might indicating potent killing effect on human liver cancer stem-like cells for GD55. This evidence concerns the gene HSPG2 and liver cancer.