Synthetic lethality of Myc overexpression and pharmacologic interference with SUMOylation. (A) P493-6 cells treated with or without tetracycline (Tet) were incubated with the indicated doses of AA and 2-D08 for 24 hours. Cells were stained with PI and DNA content was determined by flow cytometry. The fold change of the sub-G1 fraction as measure for cell death is shown (n = 3). (B) Rat-1 fibroblasts stably infected with indicated oncogenes were incubated with 25 µM AA for 48 hr (top). Cells were PI stained and DNA content analyzed by flow cytometry. The sub-G1 cell fraction is shown (n = 3). Immunoblotting for Myc expression (bottom).