**2.3 Ivermectin treatment of SILAC-labeled TOV21G cells**

When SILAC-labeled TOV21G cells achieved 80% cell density in 10-cm culture flasks, 20 μM ivermectin was added to TOV-21G cells in SILAC "heavy" labeling growing medium, and 0.1% DMSO was added to TOV-21G cells in SILAC "light" labeling growing medium for 24 h [19]. (i) Ivermectin (C48H74O14, purity ≥ 95%): The drug was brought from Solarbio (http://www.solarbio.com/goods-3911.html). (ii) TOV-21G cells were counted, and 8000 cells/well were seeded in 96-well plates. Ivermectin was added into each well in different drug concentrations (0 μM, 10 μM, 20 μM, 30 μM, 40 μM, and 50 μM) for 24 h. CCK8 (10 μL) was added into each well for 1 h to measure absorbance values (OD) at a wavelength of 450 nm. Lethal concentration 50 (IC50) was calculated according to OD values of each well in different ivermectin concentrations. (iii) Ivermectin treatment group: 20 μM ivermectin was added to TOV-21G cells in SILAC "heavy" labeling growing medium for 24 h. Control group: 0.1% DMSO was added to TOV-21G cells in SILAC "light" labeling growing medium for 24 h.
