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BinHai New Area, China

Liu X.-Z.,Fifth Central Hospital of Tianjin
Chinese Journal of Oncology | Year: 2012

Objective: To explore if folic acid/polyamide-amine (FA/PAMAM) enhances the therapeutic effect of miR-7gene therapy for glioma in vivo. Methods: The miR-7 gene was transfected into U251 glioma cells by FA/PAMAM. The efficiency of gene transfection was assessed by fluorescence microscopy. The miR-7 level was detect by quantitative RT-PCR. Intracranial glioma models were established in thymectomized mice, and FA/PAMAM nanoparticles were transplanted into the tumors in situ 3 days later. The animal survival was recorded and the gross tumor volume and degree of edema were observed by MRI. Apoptosis in the glioma cells and expression of proliferating cell nuclear antigen(PCNA), matrix metalloproteinases 2 and 9 (MMP-2 and MMP-9) were assessed by immunohistochemistry, and EGFR and AKT-2 protein expression was detected by Western blot assay. Results: Compared with the liposomes, the FA/PAMAM nanoparticles were more efficient to transfer miR-7 gene into U251 glioma cells, MRI showed that the tumor growth was much slower in the FA/PAMAM/miR-7 group, and the animal survival time was longer. The apoptosis rate was (5.3 ± 0.9) % in the control group, (11.4 ± 2.4) % in the liposome/miR-7 group, and (17.7 ± 3.7) % in the FA/PAMAM/miR-7 group. The immunohistochemical assay showed that the levels of PCNA, MMP-2 and MMP-9 protein in the FA/PAMAM/miR-7 group were (34.6 ± 5.4) %, (24.5 ± 4.1) %, (25. 4 ± 5.1) % , respectively, significantly lower than those in the liposome/miR-7group(49.3 ± 5.9)%, (31.7 ± 7.1)% and (39.4 ±6.4)%, respectively, and those in the control group (57.3 ± 7.4)%, (45.4 ± 6.9)% and (55.1 ± 7.3) %, respectively(all P < 0.05). The expressions of EGFR and AKT-2 proteins were 1.09 ± 0.12 and 0.62 ± 0.10 in the control group, 0.63 ± 0.11 and 0.43 ± 0.07 in the liposome/miR-7 group, and significantly deceased (0.47 ± 0.09 and 0.31 ± 0.04, respectively) in the FA/PAMAM/miR-7 group (all P < 0.05). Conclusion: Compared with the liposomes, FA/PAMAM can transfect miR-7 into glioma cells with a higher efficiency in vivo, makes a longer time of the drug action, and shows a certain inhibitory effect on the growth of glioma, therefore, might become a new drug targeting agent in gene therapy forglioma.

Yang W.,Duke University | Sheng H.,Duke University | Thompson J.W.,Duke University | Zhao S.,Fifth Central Hospital of Tianjin | And 5 more authors.
Stroke | Year: 2014

BACKGROUND AND PURPOSE - : Small ubiquitin-like modifier (SUMO) conjugation is a post-translational modification associated with many human diseases. Characterization of the SUMO-modified proteome is pivotal to define the mechanistic link between SUMO conjugation and such diseases. This is particularly evident for SUMO2/3 conjugation, which is massively activated after brain ischemia/stroke, and is believed to be a protective response. The purpose of this study was to perform a comprehensive analysis of the SUMO3-modified proteome regulated by brain ischemia using a novel SUMO transgenic mouse. METHODS - : To enable SUMO proteomics analysis in vivo, we generated transgenic mice conditionally expressing tagged SUMO1-3 paralogues. Transgenic mice were subjected to 10 minutes forebrain ischemia and 1 hour of reperfusion. SUMO3-conjugated proteins were enriched by anti-FLAG affinity purification and analyzed by liquid chromatography-tandem mass spectrometry. RESULTS - : Characterization of SUMO transgenic mice demonstrated that all 3 tagged SUMO paralogues were functionally active, and expression of exogenous SUMOs did not modify the endogenous SUMOylation machinery. Proteomics analysis identified 112 putative SUMO3 substrates of which 91 candidates were more abundant in the ischemia group than the sham group. Data analysis revealed processes/pathways with putative neuroprotective functions, including glucocorticoid receptor signaling, RNA processing, and SUMOylation-dependent ubiquitin conjugation. CONCLUSIONS - : The identified proteins/pathways modulated by SUMOylation could be the key to understand the mechanisms linking SUMOylation to neuroprotection, and thus provide new promising targets for therapeutic interventions. The new transgenic mouse will be an invaluable platform for analyzing the SUMO-modified proteome in models of human disorders and thereby help to mechanistically link SUMOylation to the pathological processes. © 2014 American Heart Association, Inc.

Lan F.,Tianjin Hospital | Yang Y.,Tianjin Hospital | Han J.,Fifth Central Hospital of Tianjin | Wu Q.,Tianjin Neurosurgery Institute | And 2 more authors.
International Journal of Oncology | Year: 2016

The survival benefits of patients with glioblastoma (GBM) remain unsatisfactory due to the intrinsic or acquired resistance to temozolomide (TMZ). We elucidated the mechanisms of sulforaphane (SFN) reverse TMZ resistance in TMZ-inducing cell lines by inhibiting nuclear factor-κB (NF-κB) transcriptional activity. TMZ-resistant cell lines (U87-R and U373-R) were generated by stepwise (6 months) exposure of parental cells to TMZ. Luciferase reporter assay, biochemical assays and subcutaneous tumor establishment were used to characterize the antitumor effect of SFN. MGMT expression and 50% inhibiting concentration (IC50) values of TMZ in GBM cell lines were assessed. Next, we established that U87-R and U373-R cells presenting high IC50 of TMZ, activated NF-κB transcription and significantly increased MGMT expression compared with untreated cells. Furthermore, we revealed that SFN could significantly suppress proliferation of TMZ-resistant GBM cells. In addition, SFN effectively inhibited activity of NF-κB signaling pathway and then reduced MGMT expression to reverse the chemo-resistance to TMZ in T98G, U87-R and U373-R cell lines. Sequential combination with TMZ synergistically inhibited survival capability and increased the induction of apoptosis in TMZ-resistant GBM cells. Finally, a nude mouse model was established with U373-R cell subcutaneous tumor-bearing mice, and results showed that SFN could remarkably suppress cell growth and enhance cell death in chemo-resistant xenografts in the nude mouse model. Collectively, the present study suggests that the clinical efficacy of TMZ-based chemotherapy in TMZ-resistant GBM may be improved by combination with SFN.

Li A.,Fifth Central Hospital of Tianjin | Cao X.,Tianjin Medical University
Chinese Journal of Clinical Oncology | Year: 2013

The clinical classification of metastatic spinal tumors is based on the degree of malignancy, nervous system function, osteoclasia, and prognosis of patients. The application of this classification system is relatively simple. The assessment and evaluation of patients to estimate the period of survival can guide the individualized treatment of patients. Patients with clear surgical indications can choose to undergo a palliative operation, tumor resection, or total spondylectomy. Alternatively, other patients can opt to have minimally invasive surgery aside from the normal surgical approach. Stereotactic radiotherapy and intensity-modulated radiation therapy combined with the use of radiofrequency ablation, radiation, and other therapies can achieve local tumor control, relieve pain, and maintain normal neurological function. Thus, the quality of life of the patient is improved. Percutaneous vertebroplasty, radiofrequency ablation, spinal endoscopy, and other modern forms of minimally invasive surgery will have more applications in the treatment of spinal metastatic tumors.

Zhu B.,Fifth Central Hospital of Tianjin | Li Y.,Zhejiang University | Li M.,Zhejiang University | Yang X.,Jilin University | And 3 more authors.
Spinal Cord | Year: 2013

Study design:Spinal cord injury (SCI) is a devastating and common neurologic disorder that has profound influences on modern society from physical, psychosocial and socio-economic perspectives.Objectives:To analyze the dynamic changes in protein expression during SCI after ischemia-reperfusion. Methods:We used two-dimensional difference gel electrophoresis combined with matrix-assisted laser desorption/ionization time-of-flight/time-of-flight MS to give a global analysis of protein dynamic change during SCI after ischemia-reperfusion. Dynamic changes in protein expression were investigated from 6 to 48 h in SCI after ischemia-reperfusion using a proteomics tool.Results:Twenty-one proteins were identified in total, including neuronal proteins, glycometabolism enzymes, stress-related proteins and cytoskeleton-related proteins. These were divided into upregulated and downregulated groups. Results identified 24 h as a key time point when all proteins were changed dramatically. In addition, changes in Fascin expression were discovered in SCI for the first time.Conclusion:In conclusion, we observed dynamic proteome change correlated with SCI by ischemia-reperfusion, and provided a clue to this pathological mechanism by protein identification and analysis.

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