PRDX2 and neoplasm: In lung cancer, nitrosylation of Cys51 and Cys172 of peroxiredoxin-2 (Prdx2)—an antioxidant enzyme that protects tumor cells from toxic level of H2O2—impairs the formation of Prdx2/Prdx2 homodimers, repressing its antioxidant activity.