We previously demonstrated that suppressing the expression of DNA damage repairing gene H2AX contributed to the effect of Lin28A facilitating apoptosis of colon cancer cells induced by 5-Fu, then we observed the influence of both onco-proteins on the expression of H2AX in HCT116 cells, and the result revealed that Lin28A but not Lin28B inhibiting the expression of H2AX (Figure 8D), which implies that Lin28A and Lin28B enhances the chemosensitivity of colon cancer cells to 5-Fu via different mechanisms. This evidence concerns the gene H2AX and colonic neoplasm.