STAT1 and cancer: We next treated human cancer cells with TAK-243 or small interfering RNAs (siRNA) targeting UBA1 and found that treatment with TAK-243 or knockdown of UBA1 upregulated JAK1 levels; this was accompanied by an increased response to IFN-γ or IFN-β, manifested by upregulation of p-STAT1, IRF1, and surface MHC-I (Supplementary Fig. S10B–S10F).