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Objective To observe the skin ultrastructure change of electric shock death rats and to test the expression changes of hypoxia-inducible factor-2α （HIF-2α） and heart type-fatty acid-binding protein （H-FABP） of myocardial cells, in order to provide basis for forensic identification of electric shock death. Methods The electric shock model of rats was established. The 72 rats were randomly divided into control group, electric shock death group and postmortem electric shock group. Each group was divided into three subgroups, immediate （0 min）, 30 min and 60 min after death. The skin changes of rats were observed by HE staining, the changes of skin ultrastructure were observed by scanning electron microscopy, and the expression of HIF-2α and H-FABP in rats myocardium was tested by immunohistochemical staining. Results The skin in the electric shock death group and postmortem electric shock group had no significant difference through the naked eye or by HE staining. Under the scanning electron microscope, a large number of cellular debris, cells with unclear boundaries, withered cracks, circular or elliptical holes scattered on the cell surface and irregular edges were observed. A large number of spherical foreign body particles were observed. Compared with the control group, the expression of HIF-2α in all electric shock death subgroups increased, reaching the peak immediately after death. In the postmortem electric shock group, HIF-2α expression only increased immediately after death, but was lower than that of electric shock death group （P<0.05）. Compared with the control group, the expression of H-FABP in all subgroups of electric shock death group and postmortem electric shock group significantly decreased. The expression of H-FABP in all subgroups of electric shock death group was lower than that of the postmortem electric shock group （P<0.05）. Conclusion Electric shock can increase HIF-2α expression and decrease H-FABP expression in the myocardium, which may be of forensic significance for the determination of electric shock death and identification of antemortem and postmortem electric shock.
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Animals , Rats , Autopsy , Basic Helix-Loop-Helix Transcription Factors/metabolism , Fatty Acid Binding Protein 3/metabolism , Myocardium/metabolism , Myocytes, Cardiac/metabolism , Skin/ultrastructureABSTRACT
Objective To explore the expressions of hypoxia inducible factor ( HIF), vascular endothelial growth factor receptor 2 ( VEGFR 2), and microvessel density ( MVD) in adrenocortical adenoma ( ACA) and adrenocortical carcinoma ( ACC), in order to discuss their potential role in the development of adrenal tumours. Methods Fifty-five adrenal tumour specimens resected in the hospital with complete clinical data (including 30 ACA cases and 25 ACC cases) were examined by immunohistochemistry for the expressions of HIF-2α, HIF-1α, VEGFR 2, and MVD. Results VEGFR 2 and MVD up-regulated were found in the ACC group (P＜0.05). The expression of HIF-2α and HIF-1α correlated with VEGFR 2 (P＜0.05). The expressions of VEGFR 2 and MVD were related to some clinicopathological features ( P＜0. 05 ). Additionally, tumour size, expression of VEGFR 2 and MVD were independently associated with ACC (P＜0.05). Conclusions The high expression of HIF-2α, VEGFR 2, and MVD in adrenal tumours suggested their roles in tumour angiogenesis, which indicated that anti-angiogenesis therapies deserve intensive studies for malignant adrenocortical tumours.
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Purpose To identify the binding of hypoxia in-ducible factor-2a (HIF-2 a) to the hypoxia-response element(HRE) of the matrixmetallo proteinases-2 (MMP-2) gene promoter region and clear the binding site. Methods Electro-phoretic mobility shift assay (EMSA) was used to identify the binding of HIF-2 a to HRE of the MMP-2 gene promoter region in vitro. At the same time, the chromatin immunoprecipitation assay (CHIP) was used to further determine the binding site. Results Successful prediction of two potential HIF-2a binding sites of MMP-2 the promoter region, which were-217～-204 and-1 029 ～-1 007, respectively. Probe test shows that the marked efficiency of sense chain and antisense chain was above 50％, and they could be used for EMSA-electrophoretic mobility shift assay. The results of EMSA showed that there was a binding site of HIF-2 a sense chain and antisense chain moter region int-217～-204. The results of chromatin immuno-precipitation showed that in the experimental group and control group an about 250 bp fragment in MMP-2 promoter containing HRE region was amplified, suggesting that the protein of HIF-2a binded to the HRE in MMP-2 promoter region in vivo. Conclusion HIF-2 a in MMP-2 promoter regionne promoter region in vitro and in vivo.
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Objective To study the expression of HIF-2α and VEGF in colorectal cancer and to investigate the relationship between them and clinicopathologic parameter.Methods Immunohistochemistry staining was conducted to detect the expression of HIF-2α and VEGF protein in 67 samples of colorectal tumor tissues and 67 samples of normal adjacent tissue.Results The expression of HIF-2α and VEGF in colorectal cancer tissues was significantly higher than that in adjacent tissues.The expression of HIF-2α and VEGF increased with the clinical stage and lymph node metastasis.The expression of HIF-2α increased with the tumor volume.The expression of HIF-2α and VEGF was not related to the age,sex,tumor location and tumor differentiation of the patients.HIF-2α was positively correlated with VEGF expression.Kaplan-Meier survival analysis showed that HIF-2α expression was associated with survival,that is,the higher expression of HIF-2α the worse of prognosis was obtained.Conclusion HIF-2α is involved in the process of growth,invasion and metastasis of colorectal cancer.This process may be related to the regulation of VEGF expression.
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Objective@#To investigate the effect of hypoxia inducible factor 2α (HIF-2α) on regulating CUB domain-containing protein 1 (CDCP1) and its role in hepatocellular carcinoma metastasis.@*Methods@#HIF-2α-knocked down and HIF-2α-stably overexpressing cells (MHCC97H) were prepared by small interfering RNA (siRNA) and lentivirus transfection, respectively. The expression of CDCP1 protein and mRNA in the above cells was detected by western blot and real-time PCR. The effect of HIF-2α on cell invasion ability was determined by Transwell assay. Furthermore, immunohistochemical staining was performed to detect the expression of CDCP1 in human HCC tissue samples.@*Results@#Both HIF-2α and CDCP1 were induced under hypoxic conditions. The activation of CDCP1 under hypoxic conditions was dependent on the expression of HIF-2α.When HIF-2α was overexpressed, the mRNA level of CDCP1 was greatly upregulated (5.92±0.28, P<0.05). When HIF-2α was knocked down by siRNA for 48 h and 72 h, the expression of CDCP1 was significantly downregulated (48 h: 0.25±0.04; 72 h: 0.18±0.02, all P<0.05). Moreover, analysis of human HCC samples showed that CDCP1 expression was correlated with tumor-free survival (P<0.05).@*Conclusions@#The results of this study indicate that the expression of CDCP1 is regulated by HIF-2α and is correlated with the progression of HCC. Inhibition of HIF-2α/CDCP1 may play certain inhibitory role in the metastasis of HCC.
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Objective To investigate the mechanisms of hypoxia inducible factor-2 alpha (HIF-2a) regulating human umbilical vein endothelial cells (HUVECs) under hypoxic conditions.Methods The experimental study was adopted.(1) HUVECs in logarithmic growth phase were taken:HUVECs without any disposals as control group,HUVECs with shRNA transfection control as shRNA control group,HUVECs with HIF-2α shRNA transfection as HIF-2α shRNA group and HUVECs with HIF-2α shRNA transfection then added rhAng-2 as HIF-2α ± rh-Ang-2 group.(2) Western blot testing:the expressions of Ang-2 and HIF-2α proteins in HUVECs were cultured under hypoxia conditions at 0,2,4,8,12,16,20 hours,and the levels of which were detected in the control group,shRNA control group and HIF-2α shRNA group.(3) Enzyme-linked immunosorbent assay(ELISA):the level of Ang-2 protein in supernatant of HUVECs was detected in the control group,shRNA control group and HIF-2α shRNA group.(4)The amounts of endothelial cell tubes in HUVECs among the 4 groups were detected by tube formation experimental testing.(5) Transwell method was performed to detect the amounts of cells migration in HUVECs and hepatoma cells SMMC-7721 migration intervened by supernatant of HUVECs among the 4 groups.Measurement data with normal distribution were presented as x ± s,repeated measurement data were analyzed by the repeated measures ANOVA,comparison among groups and pairwise comparison were conducted respectively by the one-way ANOVA and Dunnett's test.Results (1) Western blot test:the expression levels of Ang-2 and HIF-2α proteins in HUVECs under hypoxia conditions at 0,2,4,8,12,16,20 hours were 0.110 ±0.011,0.120 ±0.020,0.210 ±0.070,0.410 ±0.100,0.520 ± 0.090,0.790±0.130 1.010 ±0.220 and 0.180 ±0.090,0.410 ±0.070,0.470 ±0.110,0.470 ±0.070,0.580 ± 0.120,0.690 ± 0.140,0.920 ± 0.130,respectively,and which were increased after culturing under hypoxia conditions and had an ascending tendency as the hypoxia time extended,with statistically significant differences (F =403.550,3 265.587,P ＜ 0.05).The expression levels of Ang-2 and HIF-2α proteins in the control group,shRNA control group and HIF-2α shRNA group were 1.030 ±0.180,1.070 ±0.120,0.210 ± 0.070,and 0.940 ± 0.110,0.930 ± 0.190,0.170 ± 0.021,respectively,showing statistically significant differences (F =290.242,26.688,P ＜ 0.05).(2) The results of ELISA:the expression levels of Ang-2 in the control group,shRNA control group and HIF-2α shRNA group were (433.2 ±9.7)ng/L,(438.3 ± 2.6)ng/L,(114.6 ± 4.2) ng/L,with a statistically significant difference (F =2 642.180,P ＜ 0.05).(3) The results of tube formation experiments:the number of endothelial cell tubes in the control group,shRNA control group,HIF-2α shRNA group and HIF-2α ± rh-Ang-2 group were 48.3 ± 2.5,47.4 ± 3.1,19.7 ± 1.5 and 38.3 ± 2.1,respectively,with a statistically significant difference (F =148.196,P ＜ 0.05).(4) The results of Transwell method:① the number of HUVECs migration in the control group,shRNA control group,HIF-2α shRNA group and HIF-2α + rh-Ang-2 group were 140.3-± 3.5,142.7 ± 2.1,42.7 ± 3.1 and 78.1 ± 4.2,respectively,showing a statistically significant differences (F =212.205,P ＜ 0.05).②The results of Transwell method:the number of SMMC-7721 cells migration after intervening using four different supernatant in the control group,shRNA control group,HIF-2α shRNA group and HIF-2α ± rh-Ang-2 group were 106.7 ± 5.5,102.7 ± 6.6,63.0 ± 3.3 and 96.7 ± 2.1,respectively,showing a statistically significant difference (F =55.122,P ＜ 0.05).Conclusion HIF-2a could not only affect HUVECs formation but also promote SMMC-7721 cells migration via regulating Ang-2 expression.
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Objective:To investigate the expression of hypoxia-inducible factor-2α (HIF-2α)in non-small cell lung cancer (NSCLC)tissue,and to analyze its relationships with angiogenesis,cell proliferation and chemotherapy resistance. Methods: Total 112 cases of NSCLC and 20 cases of normal lung tissues were selected, immunohistochemical method was used to detect the expressions of HIF-2α,CD31,Ki67 and GST-π in 112 cases of cancer tissue and 20 cases of normal lung tissue,and the correlations of HIF-2α expression with microvessel density (MVD),Ki67, and GST-π were analyzed.Results:The positive expression rate of HIF-2α in NSCLC tissue was significantly higher than that in normal lung tissue (P < 0.05 ), the expression rate of HIF-2α in 112 cases of NSCLC was 47.3% (53/112).The MVD in HIF-2α protein high expression NSCLC group (31.1 ± 14.7)was higher than that in HIF-2αprotein low expression NSCLC group (24.3±15.8)(P <0.05).The cases of high expression of Ki67 in HIF-2αhigh expression group occupied 54.7% (29/53),and it was higher than that in HIF-2αlow expression group (16/59,27.1%);there was significant difference (r = 0.281,P = 0.003).The high expression of HIF-2α had no obvious correlation with the expression of GST-π (r = 0.122,P = 0.202). Conclusion:HIF-2αmay play an important role in the carcinogenesis and development of NSCLC by promoting the angiogenesis and enhancing the cell proliferation of NSCLC,but it may have no correlation with chemotherapy resistance.