The biological function of peroxiredoxin II on Hep3B cells and its underlying mechanism / 中华肝脏病杂志

<p><b>OBJECTIVES</b>To study the biological function and its possible underlying mechanism of peroxiredoxin II (PrxII) in liver cancer cell line Hep3B.</p><p><b>METHODS</b>Two pairs of double-stranded small interfering RNA (siRNA) targeted on PrxII gene were transfected into Hep3B cells using LipofectamineTM 2000. After confirming the inhibited effects of these siRNAs through Quant SYBR Green polymerase chain reaction and Western blot, the biological characters of Hep3B cell were analyzed by flow cytometry analysis, MTT and colony formation assays. Furthermore, dichlorodihydrofluorescein diacetate (DCFH-DA) and thiobarbituric acid (TBA) assays, for measuring the products of oxidative reaction, such as the reactive oxygen species (ROS) and malondialdehyde (MDA), were applied to explore whether the antioxidant mechanism was involved in the effects of PrxII functioning on Hep3B cell.</p><p><b>RESULTS</b>The two pairs of siRNA significantly inhibited PrxII mRNA and protein expression. Compared to the mock and blank control groups, the two PrxII-silent groups showed decreased rates of cell growth and clone formation and increased rates of cell apoptosis. The numbers of the formed colonies were 42.0+/-2.8 and 40.5+/-0.7 respectively in the two PrxII-silent groups, while they were 121.5+/-2.1 and 130.0+/-1.4 in the mock and blank control groups (P less than 0.05). The levels of endogenous ROS and MDA were significantly higher in the two PrxII-silent groups than those in the mock and blank control groups (P less than 0.05).</p><p><b>CONCLUSION</b>PrxII might play an important role in the hepatocarcinogenesis, possibly through an antioxidant function which may provide a favorable microenvironment for cancer cell survival and progression.</p>

The expression of peroxiredoxin II in hepatocellular carcinoma and its significance / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To evaluate the mRNA and protein expressions of peroxiredoxin II (PrxII) in hepatocellular carcinoma (HCC) and their significance.</p><p><b>METHODS</b>HCC was induced by aflatoxin B1 (AFB1) in 6 tree shrews (Tupaia belangeri chinensis). The expression levels of PrxII mRNA and protein were detected by reverse transcriptase polymerase chain reaction (RT-PCR) and Western blot on HCC tissues and on their surrounding liver tissues (para-HCC). Biopsied liver tissues were taken before the HCC induction (pre-HCC) from the same animals and from a group of blank controlled animals that served as controls. Liver biopsy specimens from 18 cases of human HCC and from 17 healthy human volunteers were studied using the same methods.</p><p><b>RESULTS</b>The mRNA and protein expressions of PrxII in tree shrew HCC tissues were significantly higher than those in para-HCC and pre-HCC tissues, and also higher than those in the liver tissues from the control animals (all P < 0.05). The expression levels of PrxII mRNA and protein in human HCC tissues were also significantly higher than those in their para-HCC tissues and in the human normal liver tissues (P < 0.05).</p><p><b>CONCLUSION</b>PrxII might play an important role in hepatocarcinogenesis and might be used as a molecular target for HCC prevention and treatment.</p>