GSTO1 (glutathione S-transferase omega 1) is a multifunctional oxidoreductase enzyme that catalyzes glutathione-dependent thiol transfer and dehydroascorbate reduction reactions 1. The enzyme exhibits glutathione transferase activity and participates in xenobiotic biotransformation, particularly in arsenic metabolism 2. GSTO1 regulates cellular signaling through protein deglutathionylation, a posttranslational modification mechanism dependent on its active-site cysteine 32 residue 1. In neuroblastoma cells, GSTO1-1 modulates Akt and MEK1/2 kinase activation through glutathionylation modifications and direct protein interactions 3. Clinically, GSTO1 dysregulation associates with multiple disease states. In lung adenocarcinoma, GSTO1 upregulation confers EGFR-TKI resistance through NPM1 deglutathionylation, activating the AKT/NF-κB pathway 1. The GSTO1 A140D polymorphism (rs4925) increases PCOS susceptibility 2.17-fold 4, while the same variant elevates gastric atrophy and precancerous lesion risk in Helicobacter pylori-infected individuals 5. In cervical cancer, N-glycosylation of GSTO1 promotes migration and invasion through JAK/STAT3 pathway activation 6. GSTO1 expression also correlates with oxidative stress-related conditions including asthma 7 and PCOS, where plasma GSTO1 levels decrease following GLP-1RA treatment 8. These findings establish GSTO1 as a redox-sensitive enzyme with significant roles in disease progression and therapeutic resistance.