Fig. 4. In silico screen of FDA-approved molecules for STT3B inhibitor.

a Schematic design of in silico screen to identify STT3B inhibitors. Minimized affinity screen and NNScore2 screen were subsequently performed. b Relative cell viability of HAP1 cells pretreated for 12 h with the indicated small molecule inhibitors at 10 μM and then treated with 3 μM AMA (n = 3 biological replicates). c Relative cell viability of HAP1 cells treated with the indicated small molecule inhibitors at 10 μM for 60 h (n = 3 biological replicates). d 3D Overview and close-up views of binding sites of STT3B and ICG (generated by PyMOL). ICG is shown in light orange. STT3B residues interacting with ICG are shown in cyan. Hydrogen bonds are shown in dashed green lines, and pi-pi stacking is shown in dashed yellow lines. e 2D STT3B-ICG interaction diagrams (generated by LigPlot + ). ICG is shown in blue, hydrogen-bonding residues are shown in purple, and hydrogen bonds are shown in green dotted lines, the spoked arcs represent residues making nonbonded contacts with ICG. f, g The pretreatment of ICG reduces AMA-induced cell death. Cells were pre-treated with ICG for 12 h and then treated with AMA (3 μM for HAP1 and 5 μM for HepG2) for 48 h (n = 3 biological replicates). h, i The pre-treatment and post-treatment of ICG (10 μM for HAP1 and 100 μM for HepG2) protected HAP1 (3 μM) and HepG2 (5 μM) cells from AMA-induced cell death (n = 3 biological replicates). ^nsp > 0.9999, ****p < 0.0001, ***p = 0.0007; ^nsp = 0.9840, ****p < 0.0001, *p = 0.0181. The statistics were assessed using one-way ANOVA followed by Tukey’s multiple comparisons test. j, k Calcein/PI viability assay of HAP1 cells and HepG2 cells pretreated with ICG for 12 h and then treated with AMA at 3 μM for HAP1 cells j and at 5 μM for HepG2 cells k. Scale bars are 500 μm. Data are presented as mean ± SD.  and are representative of three independent experiments. Source data are provided as a Source Data file.