1.Development of Ebp1 in tumor proliferation and invasion
Yuan LIU ; Fei ZHANG ; Ruifang NIU
Chinese Journal of Clinical Oncology 2014;(23):1536-1539
This work summarizes the research development and molecular mechanism of Ebp1, a member of the proliferation-associated 2G4 family, in tumor proliferation and invasion. This research serves as a basis and support for further research on the mechanism of tumor proliferation and invasion. The low expression of Ebp1 in various cancers promotes tumor proliferation and invasion. Ebp1 inhibits E2F1, cyclin D1, and cyclin E transcription by interacting with Rb, human histone deacetylase 2, and the transcriptional repressor Sin3A. This inhibition triggers cell cycle arrest and suppresses cell proliferation. Ebp1 also influences cancer invasion and migration. However, the underlying mechanisms remain unknown and require further exploration.
2.The research about bcl-2/bax/fas/fasL mRNA of splenic lymphocytes in HIBD rat model
Rui YAN ; Guilan CHU ; Rongxiu ZHENG ; Ruifang NIU ; Fei ZHANG
Chinese Journal of Microbiology and Immunology 2010;30(10):937-941
Objective To obtain the change of bcl-2/bax/fas/fasL in splenic lymphoctyes with different lasting time of hypoxicischemic brain damage (HIBD). Methods The newborn rat were divided into 6 groups by the time of being HIBD model randomly, includes 1/6/12/24/48/72 hour(s) (8 for every group),and control groups were established at the same time point. The following four apoptosis related genes bcl-2/bax/fas/fasL were tested by real time PCR. Results ( 1 ) bcl-2: the mRNA expressions of HIBD groups were lower than control groups at the same time ( P<0.01 ). Eliminated the control effects, the mRNA expressions of HIBD groups were differernt by the modeling time(P <0.01 ). (2)bax: the mRNA expressions of HIBD groups were higher than control groups at the same time( P <0.01 ), and in control group the expression of 6 h was much higher than any other groups (P<0.01 ). Eliminated the control effects, the mRNA expressions of H IBD groups were different by the modeling time( P<0.01 ). (3)bcl-2/bax: the ratios of HIBD groups were lower than control groups at the same time( P <0.05 ), the ratios in control groups were higher than 1 ( except for 1 h); while in HIBI) groups the ratios were lower than 1; Eliminated the control effects, the ratios were different in all the groups. (4)fas: the mRNA expressions of HIBD groups were higher than control groups at the same time ( P <0.01 ), and both were maximum at 6 h. (5)fasL: the mRNA expressions of HIBD groups were higher than control groups in 1 h and 6 h ( P<0.01 ), while lower than control group at other time points( P<0.01 ),the expression of 24 h was the maximum of control groups and 12 h was the maximum of HIBD groups. (6)fas/fasL: the ratios of HIBD groups were higher than control groups( P <0.01 ) (except for 6 h), and the ratios in control groups were lower than 1 ( P<0.01 ) ( except for 6 h), and not concentrated, while in HIBD groups were higher than 1 ( except for 24 h), between 0.69 to 5.65. Conclusion Pro-apoptosis genes ( include bax/fas/fasL) were promoted by HIBD, while anti-apoptosis gene(bcl-2) was inhibited. The maximum of pro-apoptosis genes became early in HIBD. Both the pro- and anti-apoptosis genes got their maximum at 6 h and 12 h of HIBD. The apoptosis suppression was the main effects in control groups from the ratio of bcl-2/bax, which was lower than 1. The apoptosis promotion was the main effects in HIBD groups from the ratio of bcl-2/bax, which was higher than 1, especially at 12 h. Thefas/fasL effect which is the major way of lymphocytes apoptosis was strengthened in HIBD.
3.Research progress of hypoxia-inducible factor 1 inhibitors against tumors.
Fei NIU ; Yan LI ; Fang-Fang LAI ; Xiao-Guang CHEN
Acta Pharmaceutica Sinica 2014;49(6):832-836
Hypoxia occurs in chronic and acute vascular diseases and tumor formation. The ability of tumor cells to maintain a balance between an adaptation to hypoxia and cell death is regulated by a family of transcription factors called hypoxia-inducible factor 1 (HIF-1). Tumor hypoxia mediated by HIF-1 would facilitate the likelihood of resistance to chemotherapy and radiotherapy, proliferation, metastasis and the invasive potential; all of which culminate in a decrease in patient survival. And HIF-1 alpha subunit decides the activity of HIF-1, which is regulated by oxygen. So understanding the role of HIF in signal pathway, drug resistance mechanism and its feature is crucial for developing novel anticancer therapies. In recent years, more attentions have focused on HIF-1 alpha inhibitors. It is expected that development of more potent and selective HIF inhibitors will provide an effective treatment of cancer and other HIF-related diseases. So we will focus on the biological characteristics and mechanism of HIF-1 to review currently studied HIF-1 inhibitors.
Cell Death
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Humans
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Hypoxia-Inducible Factor 1
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antagonists & inhibitors
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metabolism
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Hypoxia-Inducible Factor 1, alpha Subunit
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antagonists & inhibitors
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metabolism
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Neoplasms
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drug therapy
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Oxygen
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metabolism
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Signal Transduction
5.Endoplasmic reticulum stress participates in uric acid-induced phenotypic transformation of renal tubular epithelial cells
Pu WU ; Fei ZHAO ; Dan NIU ; Xinyang WANG ; Yaning HAO
Chinese Journal of Nephrology 2016;32(12):922-927
Objective To explore the effect of endoplasmic reticulum stress (ER stress) in uric acid?induced phenotypic change in renal tubular epithelial cells (HK?2). Methods (1) HK?2 cells were cultured with 0, 75, 150, 225, 300 mg/L uric acid for 24 h in vitro. (2) The cells were divided into normal control group, ER stress inhibitor 4?PBA (5 μmol/L) group, uric acid (150 mg/L) group and 4?PBA+uric acid group for 24 h. Morphological changes of HK?2 cells were observed under inverted microscope. MTT assay was used to detect the proliferation of HK?2 cells treated with 150 mg/L uric acid for 24, 48 and 72 h. The protein expressions of α?smooth muscle actin (α?SMA), vimentin, snail, glucose regulated protein 78 (GRP78) and the phosphorylation of eukaryotic initiation factor 2α(p?eIF2α) in HK?2 cells were measured by Western blotting. Results Compared with the control group, HK?2 cells in uric acid groups (150, 225, 300 mg/L) showed fibroblast?like appearance. The protein expressions of α?SMA, vimentin, snail, GRP78 and p?eIF2α in 150 mg/L and 225 mg/L uric acid groups were higher than those in the control group (all P<0.05). The proliferation of HK?2 cells in 150 mg/L uric acid group was lower than that in control group at 48 and 72 h (all P<0.01). Compared with the uric acid group, the cell morphology in 4?PBA+uric acid group was improved, and the protein expressions ofα?SMA, vimentin, snail, GRP78 and p?eIF2α were decreased (all P<0.05). Conclusions Uric acid may induce the phenotype transformation of renal tubular epithelial cell, and ER stress is involved. 4?PBA may inhibit the uric acid?induced ER stress response and phenotypic transformation, and may be beneficial in attenuating uric acid?induced renal tubular damage.
6.The protective effects of hyperbaric oxygen in traumatic brain injury
Feng NIU ; Biqin CHEN ; Qiangfeng FEI ; Guiying FENG ; Hongping TANG
Chinese Journal of Physical Medicine and Rehabilitation 2016;38(5):335-339
Objective To explore any protective effect of hyperbaric oxygen in traumatic brain injury and its effect on the expression of silent information regulator 1 ( SIRT1) . Methods Sixty mice were randomly divided into a control group (n=20), a brain injury group (TBI, n=20) and a hyperbaric oxygen therapy group (TBI+HBO, n=20) . The mice in the TBI and TBI + HBO groups were given massive blows to establish closed brain injuries, while in the control group the scalp was incised and a bone window was removed without brain damage. The mice in the TBI + HBO group were given hyperbaric oxygen treatment twice per day for five days, while those in the TBI and control groups were put in the hyperbaric chamber but not given HBO treatment. At one hour after the trauma and on 5 days afterward, the neurological functioning of the mice was measured to generate neurological severity scores. Brain tissue was resected for triphenyl tetrazolium staining to measure the infarct area. Cortical neurons were isolated to eval-uate the SIRT1 expression using immunofluorescence and Western blotting. Results No significant difference in the average NSS score was observed between the TBI and TBI+HBO groups one hour after modeling. The average NSS score in the TBI group subsequently increased and then decreased gradually until the fifth day. The average NSS score of the TBI+HBO group was significantly lower than that of the TBI group after the onset of the treatment at the differ-ent time points, decreasing to (2.11±0.43) on the 5thday compared with (4.06±0.54) in the TBI+HBO group. On the 2nd day after the trauma, the cerebral infarction areas of the TBI and TBI+HBO groups were significantly larger than in the control group. During the treatment, the infarction area of the TBI+HBO group decreased gradually until on the 5th day it was significantly smaller than that of the TBI group. Traumatic brain injury significantly down-regula-ted SIRT1 protein compared with the control group, but the hyperbaric oxygen therapy significantly increased the ex-pression of SIRT1 compared with the TBI group. Conclusion Hyperbaric oxygen therapy can significantly relieve traumatic brain injury, reducing NSS scores and the infarcted area and enhancing SIRT1 expression, at least in mice.
7.Transmural mechanics at the infarcted myocardium of a dog model of acute myocardial infarction
Junli WANG ; Lixue YIN ; Liping FEI ; Qingying NIU ; Wenhua LI
Chinese Journal of Tissue Engineering Research 2014;(27):4293-4298
BACKGROUND:Acute myocardial infarction with acute onset is dangerous, but the aided diagnosis for hyperacute disease mainly depends on electrocardiogram. The advantages of tissue Doppler strain imaging were utilized to help early diagnosis of acute myocardial infarction.
OBJECTIVE:To observe left ventricular transmural peak radial strain and strain time-to-peak of subendocardiac muscle, midmyocardium and subepicardiac muscle using tissue Doppler strain imaging in dogs before and after acute myocardial infarction, and to assess its mechanical characteristics.
METHODS:A total of 16 Beagle dog models of acute myocardial ischemia were established by ligating left anterior descending coronary artery. The two-dimensional apical short-axis views of the left ventricle in five complete cardiac cycles were acquired and stored in TDI-Q workstation before and after acute myocardial ischemia. Transmural peak radial strain and strain time-to-peak of segment, subendocardiac muscle, midmyocardium and subepicardiac muscle at infarct region and baseline were observed.
RESULTS AND CONCLUSION:Peak radial strains at infarct and subendocardiac muscle, midmyocardium and subepicardiac muscle were decreased compared with the baseline (P<0.05). Peak strain gradient disappeared in each layer of infarct myocardium. Strain time-to-peak of the whole segment and infarct myocardium at different layers was significantly postponed (P<0.05). There was a positive correlation of peak radial strain between subendocardium and segment as wel as between medium and segment at baseline (r=0.617, P<0.01;r=0.556, P<0.01). This relationship disappeared at infarct region (r=0.338, P>0.05;r=0.218, P>0.05). Results indicated that after acute myocardial infarction, peak strain gradient disappeared at different layers at infarct region. Acute myocardial ischemia induces peak radial strain decrease at subendocardium, medium, subepicardium and strain time-to-peak at infarct region was significantly postponed, which reflected abnormal cardiac structure and dysfunction, resulted in uncoordinated cardiac motion and asynchronous heart movement. This may be an important mechanical mechanism triggering heart failure.
8.Research progress of hypoxia-inducible factor 1 inhibitors against tumors.
Fei NIU ; Yan LI ; Fangfang LAI ; Xiaoguang CHEN
Acta Pharmaceutica Sinica 2014;49(6):832-6
Hypoxia occurs in chronic and acute vascular diseases and tumor formation. The ability of tumor cells to maintain a balance between an adaptation to hypoxia and cell death is regulated by a family of transcription factors called hypoxia-inducible factor 1 (HIF-1). Tumor hypoxia mediated by HIF-1 would facilitate the likelihood of resistance to chemotherapy and radiotherapy, proliferation, metastasis and the invasive potential; all of which culminate in a decrease in patient survival. And HIF-1 alpha subunit decides the activity of HIF-1, which is regulated by oxygen. So understanding the role of HIF in signal pathway, drug resistance mechanism and its feature is crucial for developing novel anticancer therapies. In recent years, more attentions have focused on HIF-1 alpha inhibitors. It is expected that development of more potent and selective HIF inhibitors will provide an effective treatment of cancer and other HIF-related diseases. So we will focus on the biological characteristics and mechanism of HIF-1 to review currently studied HIF-1 inhibitors.
9.Development of a novel screening assay for inhibitors targeting HIF-1alpha and P300 interaction.
Fangfang LAI ; Fei NIU ; Hanze YANG ; Wanqi ZHOU ; Xiaoguang CHEN
Acta Pharmaceutica Sinica 2014;49(6):849-53
Hypoxia is a general characteristic of most solid malignancies and intimately related to cancer progression. Homeostatic response to hypoxia is primarily mediated by hypoxia inducible factor-1alpha (HIF-1alpha) that elicits transcriptional activity through recruitment P300 coactivator. Targeting the interaction of HIF- alpha and P300 would thus constitute a novel approach for cancer treatment by suppressing tumor angiogenesis and metastasis. Here, a screening assay was developed for inhibitors targeting the interaction between HIF-1alpha and P300. The nucleotide sequence of human HIF-1alpha and P300 were cloned into pBIND and pACT vectors, named pBIND-HIF1alpha and pACT-P300. The interaction of HIF-1alpha and P300 was identified in HEK293 cell using mammalian two-hybrid system. And compound chetomin decreased their interaction in this mammalian two-hybrid system. We further verified HIF-1 inhibition effect of chetomin in U251-HRE cells. Therefore, we established a screening assay combined HIF-1alpha and P300 mammalian two-hybrid system and U251-HRE reporter assay for HIF-1 selective inhibitors.
10.Simulation of respiratory motion effect on dose distributions in three-dimensional radiotherapy
Zhenle FEI ; Zhenyang NIU ; Zhijie LI ; Lei WANG
Chinese Journal of Radiation Oncology 2012;(6):554-556
Objective To evaluate the effects of respiratory on dose distributions in threedimensional conformal radiotherapy (3 DCRT) and intensity-modulated radiotherapy (IMRT).Methods The dose distributions were measured with a PTW 2D-ARRAY seven29 placed on a home-made moving platform to simulate the respirator.Dosimetric comparisions for 3DCRT and IMRT plans were performed by means of Gamma analysis with 3% and 3 mm,respectively.Dose distribution measured for static treatment plans.Results The respiratory could reduce the target does and conformal index.The r pass rate (3%3 mm in 3 DCRT was greater than it in IMRT ((53.58 ± 0.74) %,(30.71 ± 1.00) %,t =57.91,P < 0.01).The failed points were mainly near the field edge,but located in the whole target volumes for IMRT plans.Conclusions It is undesirable to use IMRT techniques for tumors with large motion amplitude.3DCRT can give a reliable dose distribution by reasonably selecting the PTV margin.