PRDX2 protects hepatocellular carcinoma SMMC-7721 cells from oxidative stress.
Peroxiredoxin2 (PRDX2) is a member of the peroxiredoxin family of antioxidant enzymes. A number of previous studies have indicated that PRDX2 may serve a cell type-dependent role in tumorigenesis. Recently, PRDX2 has been identified to be the new target of miR-122a, which has been demonstrated to be frequently downregulated in hepatocellular carcinoma (HCC). Thus, PRDX2 may have a pro-tumorigenic role in HCC. Because the role of PRDX2 in HCC has not yet been reported, it is of interest to explore how PRDX2 may affect reactive oxygen species (ROS)-mediated cell death in HCC cells. The present study analyzed the effects of PRDX2 knockdown or overexpression on hydrogen peroxide (H2O2)-induced cell death in HCC SMMC-7721 cells. Tumor necrosis factor-α (TNF-α)-induced cell death upon PRDX2 knockdown or overexpression was also examined in SMMC-7721 cells. It was found that PRDX2 knockdown augmented H2O2-induced cell death in SMMC-7721 cells, whereas PRDX2 overexpression exhibited opposite effects. By contrast, PRDX2 knockdown enhanced TNF-α-induced apoptosis, whereas PRDX2 overexpression reduced it, even though both treatments showed little effects on TNF-α-induced necrosis in SMMC-7721 cells. Further exploration confirmed PRDX2 knockdown led to enhanced ROS generation in response to H2O2. Taken together, the present study supports that PRDX2 serves a pro-tumorigenic role in HCC through, at least partially, limiting ROS-mediated apoptosis under oxidative stress.
Key Laboratory of Cellular and Molecular Immunology, Henan University, Kaifeng, Henan 475001, P.R. China; Department of Molecular Immunology, Institute of Basic Medical Sciences, Beijing 100850, P.R. China.
Silei
S
Zhou
Department of Medical Oncology 2, Chinese PLA General Hospital & Chinese PLA Medical Academy, Beijing 100853, P.R. China.
Quanli
Q
Han
Clinical Laboratory, 305 Hospital of PLA, Beijing 100017, P.R. China.
Ru
R
Wang
Department of Molecular Immunology, Institute of Basic Medical Sciences, Beijing 100850, P.R. China.
Xin
X
Li
Department of Molecular Immunology, Institute of Basic Medical Sciences, Beijing 100850, P.R. China.
Qingyang
Q
Wang
Clinical Laboratory, 305 Hospital of PLA, Beijing 100017, P.R. China.
Huizhong
H
Wang
Department of Radiation Oncology, Chinese PLA General Hospital & Chinese PLA Medical Academy, Beijing 100853, P.R. China.
Jing
J
Wang
Key Laboratory of Cellular and Molecular Immunology, Henan University, Kaifeng, Henan 475001, P.R. China.
Yuanfang
Y
Ma
apoptosis; cell death; hepatocellular carcinoma; oxidative stress; peroxiredoxin 2