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Li Y.,Zhengzhou University | Li Y.,Stanford University | Hu J.,Stanford University | Guan F.,Zhengzhou University | And 6 more authors.
Oncology Reports | Year: 2013

Most human tumor cells, including glioblastoma multiforme (GBM) cells, have aberrant control of cell aging and apoptosis. Subcytotoxic concentrations of oxidative or stress-causing agents, such as hydrogen peroxide, may induce human cell senescence. Thus, induction of tumor cells into premature senescence may provide a useful in vitro model for developing novel therapeutic strategy to combat tumors. In the present study, we assessed the molecular mechanism(s) underlying senescence in GBM cells induced by copper sulfate. Following pretreatment with subcytotoxic concentrations of copper sulfate, U87-MG tumor cells showed typical aging characteristics, including reduced cell proliferation, cell enlargement, increased level of senescence-associated β-galactosidase (SA β-gal) activity, and overexpression of several senescence-associated genes, p16, p21, transforming growth factor β-1 (TGF-β1), insulin growth factor binding protein 3 (IGFBP3) and apolipoprotein J (ApoJ). We further demonstrated that the Bmi-1 pathway was downregulated in GBM cells in parallel with the induced senescence. The present study for the first time demonstrates the ability of copper to induce GBM cell senescence by downregulating Bmi-1. Source

Tian Y.,Zhengzhou University | Hu X.,Jiangsu Public Technology Service Platform of Stem Cells and Biotherapy | Hu X.,Shenzhen Beike Cell Engineering Institute | Yang B.,Zhengzhou University | And 4 more authors.
Journal of Clinical Rehabilitative Tissue Engineering Research | Year: 2010

BACKGROUND: Human mesenchymal stem cells derived from Wharton's jelly (WJCs) display the characteristics of MSCs as defined by the International Society for Cellular Therapy. They can be differentiated into bone, cartilage, adipose, muscle, and neural cells. They can also support the expansion of other stem cells, be well-tolerated by the immune system, and have the ability to home to tumors. OBJECTIVE: To investigate biological changes of WJCs and brain tumor stem cells (BTSCs) co-cultured in vitro. METHODS: WJCs cultured by situ cultivation and BTSCs used enzyme digestion way respectively, and gathering the 3rd passage of WJCs though subculturing as well as BTSCs. Two kinds of cells co-cultured in 24-well plates in serum-free medium (SFM) without any growth factor. 3 and 7 days after co-cultured respectively, CD133 expression of suspension cells in the 24-well plates were identified by flow cytometry, and immunofluorescence was performed for Nestin and glial fibrillary acidic protein (GFAP) expression of adherent cells. Co-culture supernatant (CCS) re-suspended 3rd passage of BTSCs and cultured into 96-well plates at day 3, which were used to determine the difference in cell growth curve in both groups using a microplate reader. RESULTS AND CONCLUSION: With the cocultivation days increasing, the phenomenon that tumor sphere cells began to be decomposed, adherent and differentiated observed by an inverted microscope. BTSCs in the co-cultured group expressed GFAP and Nestin when adherent and differentiated. The higher degree of malignant brain tumor tissue used in culturing BTSCs was, the higher expression of CD133 in BTSCs was. CD133+ in BTSCs declined when co-cultured with WJCs. Growth curve of brain tumor stem cells cultured in CCS compared with in SFM at day 3, which indicates that the proliferation of BTSCs inhibited obviously. Results indicated that CD133+ expression and proliferative capacity of BTSCs went down and BTSCs underwent differentiation during the co-culture in vitro. Source

Ba Y.-T.,Zhengzhou University | Ba Y.-T.,Chinese Institute of Clinical Medicine | Guan F.-X.,Zhengzhou University | Xiang H.,Jiangsu Public Technology Service Platform of Stem Cells and Biotherapy | And 11 more authors.
Journal of Clinical Rehabilitative Tissue Engineering Research | Year: 2010

BACKGROUND: During culture of mesenchymal stem cells (MSCs) derived from Wharton's jelly of human umbilical cord. MSC morphology tends to become hypertrophic and irregular. MSCs were found to have higher rate of death and not be adapt to be adherent after passage. It is necessary to find a method to maintain its stability. OBJECTIVE: To isolate MSCs from human umbilical cord wharton's jelly by tissue block method, and to investigate basic fibroblast growth factor (bFGF) effects on biological characteristics of MSCs. METHODS: Human umbilical cord mesenchymal stem cells (hUCMSCs) were separated by tissue block method. Tissue fragments in control group were cultured in growth medium consisting of Dulbecco's Modified Essential /F12 Media (DMEM/F12) and 10% volume fraction of fetal bovine serum. Tissue fragments in experiment group were cultured in growth medium including 20 ug/L bFGF besides these in control group. Time of tissue blocks emigrating from cells and morphology of cells were observed. The medium was changed every 3-4 days. When the cells reached 80%-90% confluency, they were detached with 0.25% trypsin and were passaged at a ratio of 1: 2 or 1:3. RESULTS AND CONCLUSION: A few long spindle or flat fibroblast-like cells were presented firstly after 8-10 days of incubation in control group, while in experiment group it took 6-8 days. One week later, lots of long spindle or flat fibroblast-like cells like whirlpool around micro-mass were presented in two groups. In the first 3 passages, cell morphous were similar and cells were passaged at approximately equivalent time. After passage 3, cells in experiment group were easier to be adherent, lower rate of death and better proliferation ability (shown by growth curve) in comparison with these in control group. Flow cytometry revealed that cell cycle at the passages 3 and 6 showed the percentage of G0/G1 was more than 70% respectively. CD44 and CD29 were highly expressed on the surface of passages 3 and 6 cells, whereas the expression of HLA-ABC was less positive, but there was negative for CD34, CD45 and HLA-DR. Cells from Wharton's jelly of the human umbilical cords, which have the biological characteristics of MSCs, have been isolated by tissue culture method. bFGF can shorten the time that MSCs are presented firstly, improve its adherence and proliferation ability and maintain its morphological stability in some degree, moreover keep surface marker expression stability of MSCs. Source

Zhao Z.F.,Xuchang Central Hospital | Zhao Z.F.,Zhengzhou University | Fan R.T.,Zhengzhou University | Yang Y.,Wei Erke Stem Cell Biotechnology Liaoning Co. | And 5 more authors.
Chinese Journal of Tissue Engineering Research | Year: 2013

BACKGROUND: Radiotherapy effect on of brain glioma is not ideal, and there are various possible factors that influence the therapeutic effect. OBJECTIVE: To investigate the in vitro radiosensitivity of brain cancer stem cells in brain glioma. METHODS: Glioma cells were isolated and seeded into the serum-free medium containing growth factors for culture. Glioma cells from the most active cell site were subcultured to 3-5 generations. Glioma cell vitality was assessed to determine the optimal dose of X-ray radiation. RESULTS AND CONCLUSION: Distinct difference in activities of proliferation could be found among cancer stem cells from different sites of glioma. X-ray dosages above 8 Gy had notable killing effect on brain cancer stem cells. Different irradiation dosage had different influence on cancer stem cells. Source

Wang C.-C.,Zhengzhou University | Wang C.-C.,Chinese Institute of Clinical Medicine | Bo Y.,Chinese Institute of Clinical Medicine | Bo Y.,Zhengzhou University | And 9 more authors.
Journal of Clinical Rehabilitative Tissue Engineering Research | Year: 2010

BACKGROUND: APP gene is closely associated with the onset of Alzheimer' disease. Intravenous transplantation of human amniotic mesenchymal stem cell (AMSCs) can promote the learning and memory improvement in transgenic APP+ mice with Alzheimer' disease. OBJECTIVE: To study whether the AMSCs can transfer into the brain tissue of Alzheimer's disease mice, and differentiate into the neural cell, then cure the disease after the human AMSC transplantation via tail venous injection. METHODS: Human AMSCs were isolated in vitro sterilely. At the third passage, 0.5 mL single cell suspension at 1 × 109/L was obtained and transplanted by tail venous pathway in transplantation group mice, Mice in the control group were injected with an equal volume of saline. APP-gene mice in the normal group were left intact. 5′-bromo-2-deoxyuridine (BrdU) labeled third-generation AMSCs expression was detected in mice brain tissue by immunohistochemical method. Glial fibrillary acidic protein (GFAP), Nestin and neuron specific enolase (NSE) expression was measured in the brain tissue of mice from each group. RESULTS AND CONCLUSION: Under an optical microscope, a majority of nuclei in the brain tissue of mice from transplantation group were stained blue, but some nuclei were stained brown, positive for BrdU. Compared with control group, the expression of GFAP in the brain tissue of transplanted mice was increased about 4 times, even more than in the normal group (P < 0.05). The expression of Nestin in the brain tissue of transplanted mice was increased about 10%, but still lower than the normal group nearly 20% (P < 0.05). NSE expression was decreased by 1/3, but still higher compared with the normal group (P < 0.05). Above-mentioned results have shown that human AMSC transplantation for treating Alzheimer's disease takes place by AMSCs homing to APP+ mouse brain tissue and differentiating into neural cells. Source

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