CD84 and cancer: By using the DepMap portal (https://depmap.org/portal/depmap/) (26), we analyzed CD84 mRNA levels across the entire spectrum of human cancer cell lines (n =1,197) and found a distinct elevated expression of CD84 in leukemia, especially in AML cell lines (n = 44), which we also confirmed by flow cytometry analysis (n = 9) (Supplemental Figure 1, B and C).