Peroxiredoxin V, an atypical thioredoxin peroxidase, is widely expressed in mammalian tissues. In addition, Prdx V is localized in mitochondria, peroxisome, cytosol, and nucleus. Prdx V has been reported to protect a wide range of cellular environments as antioxidant enzyme, and its dysfunctions may be implicated in several diseases, such as cancer, inflammation, and neurodegenerative disease. Identification and relative quantification of proteins affected by Prdx V may help identify novel signaling mechanisms that are important for oxidative stress response. However, the role of Prdx V in the modulation of hypoxia‐related cellular response is not studied yet. In order to examine the function of endogenous Prdx V in hypoxic condition in vivo, we generated a transgenic mouse model with Prdx V siRNA expression controlled by U6 promoter. Of many tissues, the knockdown of Prdx V expression was displayed in kidney, lung, and liver, but not spleen and skin. We conducted on the basis of nano‐UPLC‐MSE proteomic study to identify the Prdx V‐affected protein networks in hypoxic kidneys. In this study, we identified protein networks associated with oxidative stress, fatty acid metabolism, and mitochondrial dysfunction. Our results indicated that Prdx V affected to regulation of kidney homeostasis under hypoxia stress.

(‐)‐Epigallocatechin 3‐gallate (EGCG) is a potent antioxidant polyphenol in green tea that acts as an anticancer agent via both direct and indirect pathways. Although the relationship between EGCG’s anticancer effects and its antioxidant activity is not fully understood, it is known that EGCG stimulates production of reactive oxygen species (ROS), which induce oxidative stress leading to cell death. In IM9 multiple myeloma cells, EGCG acted in a dose‐ and time‐dependent manner to induce apoptotic cell death. Among the antioxidant enzymes expressed in IM9 cells, levels of peroxiredoxin (Prdx) V were selectively and significantly reduced by EGCG. Moreover, the ROS scavenger NAC completely inhibited EGCG‐induced apoptosis and PrdxV reduction, while overexpression of PrdxV, but not a PrdxVC48S mutant, protected IM9 cells from EGCG‐induced apoptosis. EGCG‐induced reductions in cell viability and PrdxV levels were also observed in primary CD138+ multiple myeloma cells from patients. These results suggest that PrdxV is a key target via which EGCG mediates its anticancer effects.