To test whether human AML cells overexpressing miR‐155 can act in trans to downregulate stromal syntenin, we co‐cultured FLT3‐ITD (miR‐155high) MOLM‐14 and AML1‐ETO9a (miR‐155low) U937 cells with HS5 cells (Gerloff et al, 2015; Salemi et al, 2015). Here, RUNX1 is linked to acute myeloid leukemia.