Peroxisomes are essential organelles that participate in multiple important metabolic processes, including the β-oxidation of fatty acids, plasmalogen synthesis, and the metabolism of reactive oxygen species (ROS). Peroxiredoxins is overexpressed in breast cancer tissues to a great extent suggesting that they has a proliferative effect and may be related to cancer development or progression. Peroxiredoxin 5 (PRDX5) is a thioredoxin peroxidase that belongs to the atypical 2-Cys class of the TSA/ahpC family of peroxiredoxins. PRDX5 is a widely expressed mitochondrial antioxidant enzyme that reduces hydrogen peroxide, alkyl hydroperoxides, and peroxynitrite. In human cells, this enzyme is present in the cytosol, mitochondria, peroxisomes, and nucleus.