S100A9 and acute myeloid leukemia: The results of the infiltration ratio of each subpopulation of NK/T cells showed that the percentage of NK cells was significantly higher in the AML group with non-CR compared to the AML group with CR, and the NK cell marker genes that were differentially expressed between the CR and non-CR groups mainly included HBA1, PREX1, S100A8 and S100A9.