Despite its potent DC50 value for HDAC6, 27 did not compromise cell viability in the cell lines tested at concentrations ranging from 0.5–50 μM, the authors noted that this is an observation similar to others studying the effects of selective HDAC6 inhibitors on cell proliferation.83 PROTAC 26, on the other hand, did compromise cell viability in three of the AML cell lines tested and was capable of inducing apoptosis, but with IC50 values in the double digit micromolar ranges. This evidence concerns the gene HDAC6 and acute myeloid leukemia.