Altered Secretory Activity of APE1/Ref-1 D148E Variants Identified in Human Patients With Bladder Cancer / 대한배뇨장애요실금학회지

PURPOSE: Apurinic/apyrimidinic endonuclease 1/redox factor-1 (APE1/Ref-1) is a multifunctional protein involved in DNA repair and redox modulation. Recently, serum and urinary APE1/Ref-1 levels were reported to be increased in patients with bladder cancer. Genetic variations of APE/Ref-1 are associated with the risk of cancer. However, the effect of APE1/Ref-1 variants on its secretory activity is yet unknown. METHODS: APE1/Ref-1 variants were evaluated by DNA sequencing analysis of reverse transcription polymerase chain reaction products in coding DNA sequences (CDS) of APE1/Ref-1 in bladder tissue samples from patients with bladder cancer (n=10). Secretory activity of APE1/Ref-1 variants was evaluated with immunoblot and enzyme-linked immunosorbent assay of the culture medium supernatants. RESULTS: Four different substitution mutants (D148E, I64V/D148E, W67R/D148E, and E86G/D148E) of APE1/Ref-1 were identified in bladder cancer specimens. However, deletion mutants of APE1/Ref-1 CDS were not found. The secretory activity of the APE1/Ref-1 variants (D148E, I64V/D148E, and E86G/D148E) was increased compared to that of wild type APE1/Ref-1. Furthermore, the secretory activity in basal or hyperacetylated conditions was much higher than that in APE1/Ref-1 D148E-transfected HEK293 cells. CONCLUSIONS: Taken together, our data suggest that the increased secretory activity of D148E might contribute to increased serum levels of APE1/Ref-1 in patients with bladder cancer.

APE1/Ref-1 as a Serological Biomarker for the Detection of Bladder Cancer / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: Apurinic/apyrimidinic endonuclease 1/redox factor-1 (APE1/Ref-1) is a multifunctional protein that shows elevated expression in a number of cancers. We attempted to determine whether serum APE1/Ref-1 is elevated in patients with bladder cancer. MATERIALS AND METHODS: Serum APE1/Ref-1 levels were determined using enzyme-linked immunosorbent assay in serum from patients with bladder cancer who had not received chemotherapy or radiotherapy (n=51) and non-tumor controls (n=55). The area under the receiver operating characteristic area under the curve was applied to determine the correlation between clinical factors and the serum levels of APE1/Ref-1. RESULTS: Serum levels of APE1/Ref-1 in bladder cancer patients were significantly elevated compared to those of the control group (3.548+/-0.333 ng/100 muL [n=51] for bladder cancer vs. 1.547+/-0.319 ng/100 muL [n=55] for the control group), with a sensitivity and specificity of 93% and 59%, respectively. Serum APE1/Ref-1 levels are associated with tumor stage, grade, muscle invasion, and recurrence. CONCLUSION: Serum APE1/Ref-1 might be useful as a potential serologic biomarker for bladder cancer.

Effect of APE1/Ref-1 on differentiation of peripheral blood mononuclear cells into osteoclast-like cells / 重庆医学

Objective To investigate the effect of APE1 on differentiation of peripheral blood mononuclear cells into osteoclast-like cells(OCL) which induced by macrophage colony stimulating factor (RANKL) and macrophage colony stimulating factor (M-CSF) .Methods Human peripheral blood mononuclear cells (PBMCs) were collected by density gradient separation ;Constructed APE1 siRNA expression vector Ad5v-APE1 siRNA was used to transfect PBMCs .Tartrate-resistant acid phosphatase (TRAP) method was conducted to identify the cells ,the expression level of APE1 was detected by Western blot ,the mRNA expression levels of Cathepsin K(CK) and V-ATPase were detected by RT-PCR .Results PBMCs transfected with APE1 siRNA had significantly lower protein expression of APE1 than untransfected cells (P< 0 .05) ;PBMCs could differentiate into OCL under the stimulation of RANKL and M-CSF ,the mRNA expression levels of CK and V-ATPase increased ;After APE1 siRNA treatment ,the number of OCL was reduced and the levels of CK and V-ATPase mRNA decreased .Conclusion PBMCs can differentiate into a large number of OCL induced by RANKL and M-CSF ,APE1 siRNA significantly inhibited differentiation of PBMCs into osteoclast-like cells , APE1 may be involved in the regulation of osteoclast-like differentiation process .

Redox Factor-1 Inhibits Cyclooxygenase-2 Expression via Inhibiting of p38 MAPK in the A549 Cells

In this study, we evaluated the role of apurinic/apyrimidinic endonuclease1/redox factor-1 (Ref-1) on the tumor necrosis factor-alpha (TNF-alpha) induced cyclooxygenase-2 (COX-2) expression using A549 lung adenocarcinoma cells. TNF-alpha induced the expression of COX-2 in A549 cells, but did not induce BEAS-2B expression. The expression of COX-2 in A549 cells was TNF-alpha dose-dependent (5~100 ng/ml). TNF-alpha-stimulated A549 cells evidenced increased Ref-1 expression in a dose-dependent manner. The adenoviral transfection of cells with AdRef-1 inhibited TNF-alpha-induced COX-2 expression relative to that seen in the control cells (Ad beta gal). Pretreatment with 10 micrometer of SB203580 suppressed TNF-alpha-induced COX-2 expression, thereby suggesting that p38 MAPK might be involved in COX-2 expression in A549 cells. The phosphorylation of p38 MAPK was increased significantly after 5 minutes of treatment with TNF-alpha, reaching a maximum level at 10 min which persisted for up to 60 min. However, p38MAPK phosphorylation was markedly suppressed in the Ref-1-overexpressed A549 cells. Taken together, our results appear to indicate that Ref-1 negatively regulates COX-2 expression in response to cytokine stimulation via the inhibition of p38 MAPK phosphorylation. In the lung cancer cell lines, Ref-1 may be involved as an important negative regulator of inflammatory gene expression.

Overexpression of Ref-1 Inhibits Lead-induced Endothelial Cell Death via the Upregulation of Catalase

The role of apurinic/apyrimidinic endonuclease1/redox factor-1 (Ref-1) on the lead (Pb)-induced cellular response was investigated in the cultured endothelial cells. Pb caused progressive cellular death in endothelial cells, which occurred in a concentration- and time-dependent manner. However, Ref-1 overexpression with AdRef-1 significantly inhibited Pb-induced cell death in the endothelial cells. Also the overexpression of Ref-1 significantly suppressed Pb-induced superoxide and hydrogen peroxide elevation in the endothelial cells. Pb exposure induced the downregulation of catalase, it was inhibited by the Ref-1 overexpression in the endothelial cells. Taken together, our data suggests that the overexpression of Ref-1 inhibited Pb-induced cell death via the upregulation of catalase in the cultured endothelial cells.

Study on correlation between expression of ref-1 and neuronal apoptosis after intracerebral hemorrhage in rats / 临床神经病学杂志

Objective To investigate the correlation between the expression of redox factor-1 (Ref-1) and neuronal apoptosis around hematoma after experimental intracerebral hemorrhage (ICH) in rats.Methods ICH model of rat was induced using stereotactic infusion antilogous blood 50 ?l into the caudate nucleus. The male animals were randomly divided into sham operation group, normal control group and hemorrhage group. TUNEL and immunohistochemistry methods were used to detect apoptosis and the expression of Ref-1 in cerebral tissues at different time, respectively.Results The expression of Ref-1 was negatively correlated with neuronal apoptosis around hematoma after ICH (r=-0.745, P

Research on apurinic/apyrimidinic endonuclease/redox-factor 1 / 第二军医大学学报

Apurinic/apyrimidinic endonuclease/redox factor 1(APE/Ref 1) is a multifunctional protein that is responsible for repairing DNA damage,it also infleunce reduction oxidation (redox) reaction and modulate the DNA binding activity of transcription factors,it is important to cell survival.Recently, much data concerning APE1/Ref 1 and information on APE1/Ref 1 in a wide variety of functions and systems have rapid growth,including its gene,function,distribution and relations with some diseases,especially nervous system diseases and tumors.