(A) Compound 9 reduces the NSD2 protein level in 293FT cells in a NSD2, CRBN-, and proteasome-dependent manner. 293FT cells were treated with 5 μM of compound 9 for 48 h. During the last 6 h, the cells were cotreated with either 10 μM of pomalidomide (PML), 5 μM of UNC6934, 5 μM of MG132, or 10 μM of MLN4924. The NSD2 protein level was detected by Western blotting with GAPDH as the loading control. (B) NSD2 degradation induced by compound 9 is reversible. 293FT cells were treated with 5 μM of compound 9 for 72 h, and compound 9 was then washed out. The NSD2 protein level was detected by Western blotting at 0, 12, 24, and 48 h post the washout. GAPDH was used as the loading control.