**4. Conclusions**

Stable isotope labeling with amino acids in cell culture (SILAC) was an effective quantitative proteomics method to identify differentially expressed proteins or differentially modified proteins in cultured cells between two different conditions. In this study, ovarian cancer cells TOV-21 under two different conditions were cultured with the "heavy" labeling medium that contained 50 mg L-lysine-2HCl [ 13C6, 15N2] and 50 mg L-arginine-HCl [13C6, 15N4] in 500 mL RPMI 1640 medium, and the "light" labeling medium that contained 50 mg L-lysine-2HCl [12C6, 14N2] and 50 mg L-arginine-HCl [12C6, 14N4] in 500 mL RPMI 1640 medium for 10 passages, respectively. Then TOV-21G cells with SILAC "heavy" or "light" labeling were treated with or without 20 μM ivermectin for 24 h. The heavy- and lightstable isotope-labeled proteins were equally mixed (1:1), digested with trypsin, and analyzed with LC-MS/MS. A total of 4447 proteins were identified in ivermectintreated TOV-21G cells relative to controls, and these proteins were significantly enriched in 89 molecular pathways, and 62 biological processes. These findings offer important data to study ivermectin-mediated molecular pathway network changes and discover effective ivermectin-related biomarkers and therapeutic targets for ivermectin treatment of ovarian cancer.
