Septins are highly conserved GTP binding proteins which regulate a variety of cellular functions including cytokinesis, polarity, cell cycle, vesicle trafficking, and exocytosis and are now considered the fourth component of the cytoskeleton. Septins are implicated in T and B cell lymphomas; and acute myeloid leukemias, where they frequently act as fusion partners with the Mixed-Lineage Leukemia (MLL) gene. Previous data in our laboratory led to the discovery of a small molecular inhibitor, DW0254, which inhibits RAS function and its downstream target RhoGTPase, Rac, including the hematopoietic-specific Rac2 GTPase, also implicated in MLL leukemias. The inhibitor leads to apoptosis of leukemia cell lines. Using biophysical methods, we discovered that DW0254 binds both the RAS chaperone, PDE6D, and Septin11, which is a member of the Septin6 family (Sara CN, et al., Blood Cancer 2022). Although Septins have been reported to be involved in function of the RhoGTPase Cdc42 and hematopoietic stem progenitor cell (HSPC) polarity, the role of Septin11 in hematopoiesis has not been reported. Septin11 is a member of the Septin6 family of proteins which consists of Septin6, 8, 10, 11 and 14 with significant homology between family members. Previous data in yeast has hypothesized functional overlap within each family of Septin proteins.