scholarly journals CSIG-18. NERVE/GLIAL ANTIGEN (NG)2 EXPRESSION IN GLIOBLASTOMA IS REGULATED BY miR-29b-3p

2019 ◽  
Vol 21 (Supplement_6) ◽  
pp. vi47-vi48
Author(s):  
Beate Schmitt ◽  
Anne Boewe ◽  
Yuan Gu ◽  
Christoph Sippl ◽  
Steffi Urbschat ◽  
...  

Abstract Overexpression of NG2 in human glioblastoma cells is associated with an elevated drug resistance and thereby worsens clinical outcome. However, the regulatory mechanisms of NG2 expression are largely unknown. In this study, we identified miR-29b-3p as a posttranscriptional factor of NG2 expression. The basal mRNA levels of miR-29b-3p and NG2 were detected in the NG2-positive glioblastoma cell lines A1207 and U87 by qRT-PCR. The cells were transfected with miR-29b-3p-mimic or scrambled-miR (control) and the expression of NG2 was analyzed by qRT-PCR, flow cytometry and Western blot. Reporter gene analyses of the NG2 promotor region and 3’UTR were performed to study the effect of miR-29b-3p on NG2 expression. Finally, we analyzed the mRNA levels of NG2 and miR-29b-3p in samples from glioblastoma patients. We found that the two NG2-positive glioblastoma cell lines A1207 and U87 are positive for miR-29b-3p. Transfection with miR-29b-3p-mimic reduced NG2 mRNA levels in A1207 (29%±9.9; Mean±SD) and U87 (6%±2.8), resulting in a significantly decreased NG2 protein expression in A1207 (67%±6.4) and U87 (75%±4) when compared to controls. The analysis of the 3’UTR revealed that miR-29b-3p is a posttranscriptional regulator of NG2 expression. Moreover, miR-29b-3p affects the pretranscriptional NG2 expression by diminishing SP-1-dependent NG2 promotor activity. These results were confirmed by the analysis of glioblastoma patient-derived samples, demonstrating that a high NG2 expression is associated with low levels of miR-29b-3p. In conclusion, we identified miR-29b-3p as a crucial regulator of NG2 expression in glioblastoma. Hence, targeting NG2 expression by miR-29b-3p may provide a novel therapeutic strategy to overcome drug resistance in NG2-positive glioblastoma cells.

2019 ◽  
Vol 78 (10) ◽  
pp. 939-948 ◽  
Author(s):  
Han Zhang ◽  
Danxia Qin ◽  
Zhixian Jiang ◽  
Jinning Zhang

Abstract Aerobic glycolysis is a characteristic in cancers that is important for cancer cell proliferation. Emerging evidence shows that long non-coding RNA (LncRNA) participates in glucose metabolism and cell proliferation in cancer. This study explored the effect of LncRNA: SNHG9 in glioblastoma. The mRNA expression of SNHG9 in human glioma tissues and glioblastoma cell lines was measured by qRT-PCR. Glioblastoma cell lines (U87 and U251) were transfected with miR-199a-5p or SNHG9-expressing plasmid and cell viability as well as concentrations of glucose and lactate were measured. The extracellular acidification was evaluated by glycolysis stress test. The Wnt2 levels were determined by qRT-PCR and Western blot. Results showed that the mRNA expression of SNHG9 was elevated in glioblastoma tissues. The elevated SNHG9 expression was related to lower survival rate in patients with glioma. SNHG9 could downregulate miR-199a-5p and upregulate Wnt2 in glioblastoma cells. Overexpression of SNHG9 in glioblastoma cells promoted aerobic glycolysis and cell proliferation, which could be attenuated by miR-199a-5p. Results of this study indicated an effect of SNHG9/miR-199a-5p/Wnt2 axis in regulating cell growth and aerobic glycolysis in glioblastoma.


Author(s):  
Yihao Zhu ◽  
Handong Wang ◽  
Maoxing Fei ◽  
Ting Tang ◽  
Wenhao Niu ◽  
...  

AbstractSmarcd1 is a component of an evolutionary conserved chromatin remodeling complex—SWI/SNF, which is involved in transcription factor recruitment, DNA replication, recombination, and repair. Suppression of the SWI/SNF complex required for cellular differentiation and gene regulation may be inducible for cell proliferation and tumorigenicity. However, the inhibitory role of Smarcd1 in human glioblastoma cells has not been well illustrated. Both U87 and U251 human glioblastoma cell lines were employed in the present study. The lentivirus-mediated gene knockdown and overexpression approach was conducted to determine the function of Smarcd1. The protein levels were tested by western blot, and the relative mRNA contents were detected by quantitative real-time PCR. Cell viability was tested by CCK-8 and colony-forming assay. Transwell assays were utilized to evaluate the motility and invasive ability. Flow cytometry was employed to analyze cell cycle and apoptosis. SPSS software was used for statistical analysis. Low expression of Smarcd1 was observed in glioblastoma cell lines and in patients with high-grade glioma. Importantly, the depletion of Smarcd1 promoted cell proliferation, invasion, and chemoresistance, whereas enhanced expression of Smarcd1 inhibited tumor-malignant phenotypes. Mechanistic research demonstrated that overexpression of Smarcd1 decreased the expression of Notch1, while knockdown of Notch1 increased the expression of Smarcd1 through Hes1 suppression. Hence, the crosstalk between Smarcd1 and Notch1, which formed a feedback loop, was crucial in regulation of glioblastoma malignant phenotypes. Furthermore, targeting Smarcd1 could be a potential strategy for human glioblastoma treatment.


2020 ◽  
Vol 12 ◽  
pp. 175883592091530 ◽  
Author(s):  
Alja Zottel ◽  
Ivana Jovčevska ◽  
Neja Šamec ◽  
Jernej Mlakar ◽  
Jernej Šribar ◽  
...  

Background: Glioblastoma is a particularly common and very aggressive primary brain tumour. One of the main causes of therapy failure is the presence of glioblastoma stem cells that are resistant to chemotherapy and radiotherapy, and that have the potential to form new tumours. This study focuses on validation of eight novel antigens, TRIM28, nucleolin, vimentin, nucleosome assembly protein 1-like 1 (NAP1L1), mitochondrial translation elongation factor (EF-TU) (TUFM), dihydropyrimidinase-related protein 2 (DPYSL2), collapsin response mediator protein 1 (CRMP1) and Aly/REF export factor (ALYREF), as putative glioblastoma targets, using nanobodies. Methods: Expression of these eight antigens was analysed at the cellular level by qPCR, ELISA and immunocytochemistry, and in tissues by immunohistochemistry. The cytotoxic effects of the nanobodies were determined using AlamarBlue and water-soluble tetrazolium tests. Annexin V/propidium iodide tests were used to determine apoptotsis/necrosis of the cells in the presence of the nanobodies. Cell migration assays were performed to determine the effects of the nanobodies on cell migration. Results: NAP1L1 and CRMP1 were significantly overexpressed in glioblastoma stem cells in comparison with astrocytes and glioblastoma cell lines at the mRNA and protein levels. Vimentin, DPYSL2 and ALYREF were overexpressed in glioblastoma cell lines only at the protein level. The functional part of the study examined the cytotoxic effects of the nanobodies on glioblastoma cell lines. Four of the nanobodies were selected in terms of their specificity towards glioblastoma cells and protein overexpression: anti-vimentin (Nb79), anti-NAP1L1 (Nb179), anti-TUFM (Nb225) and anti-DPYSL2 (Nb314). In further experiments to optimise the nanobody treatment schemes, to increase their effects, and to determine their impact on migration of glioblastoma cells, the anti-TUFM nanobody showed large cytotoxic effects on glioblastoma stem cells, while the anti-vimentin, anti-NAP1L1 and anti-DPYSL2 nanobodies were indicated as agents to target mature glioblastoma cells. The anti-vimentin nanobody also had significant effects on migration of mature glioblastoma cells. Conclusion: Nb79 (anti-vimentin), Nb179 (anti-NAP1L1), Nb225 (anti-TUFM) and Nb314 (anti-DPYSL2) nanobodies are indicated for further examination for cell targeting. The anti-TUFM nanobody, Nb225, is particularly potent for inhibition of cell growth after long-term exposure of glioblastoma stem cells, with minor effects seen for astrocytes. The anti-vimentin nanobody represents an agent for inhibition of cell migration.


Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 2409-2409
Author(s):  
Connie L. Erickson-Miller ◽  
Jennifer Kirchner ◽  
Kodandaram Pillarisetti ◽  
Lone Ottesen ◽  
Yasser Mostafa Kamel ◽  
...  

Abstract Abstract 2409 Poster Board II-386 Background: Eltrombopag (Promacta®) is a novel, oral thrombopoietin receptor (TpoR) agonist that interacts with the TpoR on bone marrow progenitors to stimulate megakaryocyte production, thus increasing platelet counts in thrombocytopenic patients. The effects of eltrombopag on the proliferation of solid tumor cell lines and the expression of thrombopoietin receptor (MPL, TpoR) on patient tumors is of interest given that chemotherapy can cause thrombocytopenia. Materials and methods: Proliferation was measured by Cell Titer Glo assay on 3 ovarian (OVCAR3, OVCAR4, SKOV3), 4 lung (A549, NCI-H226, NCI-H510, NCI-H460) and 3 breast (BT-474, MCF7, HCC1937) cancer cell lines from the ATCC treated with 0.01 – 100 ug/mL eltrombopag. Quantitative RT-PCR (qRT-PCR) for MPL expression was performed on the tumor cell lines and on 40 tumor samples, each from subjects with ovarian, lung or breast cancer. Microarray analysis for MPL mRNA expression was examined from 118 subjects with breast cancer and 29 with non-small cell lung cancer (NSCLC). Microarray data was normalized using robust multiarray average (RMA) and relative mRNA expression was determined. To determine expression of TpoR protein, western blot analyses was performed on some of the tumor cell lines. Results: Eltrombopag induced an inhibition of proliferation on all of the ovarian, lung and breast solid tumor cell lines tested. The IC50 ranged from 3.7 to 49.7 ug/mL (see table below). The Cmax of ITP patients treated with 75 mg eltrombopag is 11.4 ug/mL, demonstrating that these concentrations are clinically achievable. There was no enhancement of proliferation at any concentration of eltrombopag, consistent with the very low or undetectable level of MPL expression on samples of tumors from patients with these diseases. MPL was expressed at very low or undetectable levels in these tumor cell lines with the exception of the lung cancer line, NCI-H510. However, western blot analyses showed no detectable TpoR protein expression regardless of the higher levels of MPL mRNA in NCI-H510 cells. Erythropoietin receptor (EPOR) mRNA was expressed at low-to-moderate levels, while ERBB2 and IGF1R were expressed at higher levels in these cell lines. Microarray analysis showed undetectable MPL mRNA levels in all 118 samples from patients with breast cancer and 52% of the NSCLC samples, the remaining NSCLC samples expressed low levels of MPL. In contrast, EPOR was expressed in 75–100% of the breast cancer, and NSCLC samples. ERBB2 was expressed in 97–100% of the samples and IGF1R was expressed in 54–100% of the samples. When 40 other tumor samples each from subjects with ovarian, lung and breast cancer were examined by qRT-PCR, MPL mRNA levels were also very low or undetectable. EPOR, ERBB2, and IGF1R expression levels varied according to tumor type, but were greater than MPL levels. Conclusions: In summary, similar to its effects on leukemia and lymphoma cell lines, all of the nine lung, ovarian, breast or prostate tumor cell lines demonstrated decreased proliferation in response to eltrombopag. The undetectable or very low levels of expression of MPL mRNA in tumors of patients with lung, ovarian, breast or prostate cancer supports the proliferation results. Disclosures: Erickson-Miller: GlaxoSmithKline: Employment, Equity Ownership, Patents & Royalties, Research Funding. Kirchner:GlaxoSmithKline: Employment. Pillarisetti:GSK: Employment, Equity Ownership, Patents & Royalties. Ottesen:GSK: Employment, Equity Ownership. Mostafa Kamel:GSK: Employment, Equity Ownership. Liu:GSK: Employment, Equity Ownership. Martin:GSK: Employment, Equity Ownership. Messam:GSK: Employment, Equity Ownership.


2018 ◽  
Vol 2018 ◽  
pp. 1-11
Author(s):  
Wen Song ◽  
Zhenling Wang ◽  
Pengcheng Kan ◽  
Zhuolin Ma ◽  
Yaru Wang ◽  
...  

Background. BCL6 was a critical prooncogene of human B-cell lymphomas which promoted tumor progress and contributed to malignant behavior in several kinds of cancers. This study was to detect the expression of BCL6 and its biological effect on glioma. Methods. RT-PCR and Western blot were used to detect the expression of BCL6 mRNA and protein in tissues and glioblastoma cell lines. The expression of BCL6 was knockdown in two glioblastoma cell lines (U87 and U251) using BCL6 shRNA. The CCK8, colony-formation, flow cytometry, Transwell, and wound-healing assays were used to evaluate the malignant phenotypic change of glioblastoma cells. Results. The expression of BCL6 was higher in glioma tissues and glioblastoma cell lines than normal tissues. Knockdown of BCL6 expression reduced the proliferation, migration, and invasion of glioblastoma cells. Moreover, knockdown of BCL6 changed expression of proteins related to malignant behaviors of glioblastoma cells. The suppression of BCL6 could increase chemosensitivity of U87 and U251 to temozolomide. Downregulation of BCL6 levels suppressed the expression of BCL2, cyclin D1, MMP2, and MMP9 proteins as well as two classic signaling pathway proteins p-AKT and p-ERK. Simultaneously, BAX and p21 protein levels were upregulated along with knockdown of BCL6. Conclusions. Our results indicated that BCL6 may be a tumor oncogene involved in the progression of glioma via affecting AKT and MAPK signaling pathways.


2020 ◽  
Vol 2 (1) ◽  
Author(s):  
Ian F Parney ◽  
Michael P Gustafson ◽  
Mary Solseth ◽  
Peggy Bulur ◽  
Timothy E Peterson ◽  
...  

Abstract Background Glioblastoma, the most common primary malignant brain tumor, is nearly universally fatal by 5 years. Dendritic cell vaccines are promising but often limited clinically by antigen choice, dendritic cell potency, and/or manufacturing yield. We optimized vaccine manufacture, generating potent mature autologous dendritic cells pulsed with allogeneic glioblastoma lysates. Methods Platelet lysate-based supplement was used to establish human glioblastoma cell lines. Phenotype and genotype were assessed. An improved culture technique to generate mature dendritic cells from glioblastoma patients’ monocytes was developed. The ability of T cells stimulated with autologous dendritic cells pulsed with allogeneic glioblastoma cell lysate to kill HLA-A2-matched glioblastoma cells was assessed. Results Glioblastoma cell lines established with platelet lysate supplement grew faster and expressed more stem-like markers than lines grown in neural stem cell media or in the presence of serum. They expressed a variety of glioma-associated antigens and had genomic abnormalities characteristic of glioblastoma stable up to 15 doublings. Unlike standard culture techniques, our optimized technique produced high levels of mature dendritic cells from glioblastoma patients’ monocytes. Autologous T cells stimulated with mature dendritic cells pulsed with allogeneic glioblastoma cell line lysate briskly killed HLA-A2-matched glioblastoma cells. Conclusions Our glioblastoma culture method provides a renewable source for a broad spectrum glioblastoma neoantigens while our dendritic cell culture technique results in more mature dendritic cells in glioblastoma patients than standard techniques. This broadly applicable strategy could be easily integrated into patient care.


2006 ◽  
Vol 81 (3) ◽  
pp. 1479-1491 ◽  
Author(s):  
Guido Wollmann ◽  
Michael D. Robek ◽  
Anthony N. van den Pol

ABSTRACT With little improvement in the poor prognosis for humans with high-grade glioma brain tumors, alternative therapeutic strategies are needed. As such, selective replication-competent oncolytic viruses may be useful as a potential treatment modality. Here we test the hypothesis that defects in the interferon (IFN) pathway could be exploited to enhance the selective oncolytic profile of vesicular stomatitis virus (VSV) in glioblastoma cells. Two green fluorescent protein-expressing VSV strains, recombinant VSV and the glioma-adapted recombinant VSV-rp30a, were used to study infection of a variety of human glioblastoma cell lines compared to a panel of control cells, including normal human astrocytes, oligodendrocyte precursor cells, and primary explant cultures from human brain tissue. Infection rate, cell viability, viral replication, and IFN-α/β-related gene expression were compared in the absence and presence of IFN-α or polyriboinosinic polyribocytidylic acid [poly(I:C)], a synthetic inducer of the IFN-α/β pathway. Both VSV strains caused rapid and total infection and death of all tumor cell lines tested. To a lesser degree, normal cells were also subject to VSV infection. In contrast, IFN-α or poly(I:C) completely attenuated the infection of all primary control brain cells, whereas most glioblastoma cell lines treated with IFN-α or poly(I:C) showed little or no sign of protection and were killed by VSV. Together, our results demonstrate that activation of the interferon pathway protects normal human brain cells from VSV infection while maintaining the vulnerability of human glioblastoma cells to viral destruction.


2021 ◽  
Vol 11 ◽  
Author(s):  
Bo Yuan ◽  
Kang Xu ◽  
Ryota Shimada ◽  
JingZhe Li ◽  
Hideki Hayashi ◽  
...  

Glioblastoma is a fatal primary malignant brain tumor, and the 5-year survival rate of treated glioblastoma patients still remains <5%. Considering the sustained development of metastasis, tumor recurrence, and drug resistance, there is an urgent need for the novel therapeutic approaches to combat glioblastoma. Trivalent arsenic derivative (arsenite, AsIII) with remarkable clinical efficacy in leukemia has been shown to exert cytocidal effect against glioblastoma cells. Gamabufotalin, an active bufadienolide compound, also shows selective cytocidal effect against glioblastoma cells, and has been suggested to serve as a promising adjuvant therapeutic agent to potentiate therapeutic effect of conventional anticancer drugs. In order to gain novel insight into therapeutic approaches against glioblastoma, the cytotoxicity of AsIII and gamabufotalin was explored in the human glioblastoma cell lines U-87 and U-251. In comparison with U-251 cells, U-87 cells were highly susceptible to the two drugs, alone or in combination. More importantly, clinically achieved concentrations of AsIII combined with gamabufotalin exhibited synergistic cytotoxicity against U-87 cells, whereas showed much less cytotoxicity to human normal peripheral blood mononuclear cells. G2/M cell cycle arrest was induced by each single drug, and further augmented by their combination in U-87 cells. Downregulation of the expression levels of cdc25C, Cyclin B1, cdc2, and survivin was observed in U-87 cells treated with the combined regimen and occurred in parallel with G2/M arrest. Concomitantly, lactate dehydrogenase leakage was also observed. Intriguingly, SB203580, a specific inhibitor of p38 MAPK, intensified the cytotoxicity of the combined regimen in U-87 cells, whereas wortmannin, a potent autophagy inhibitor, significantly rescued the cells. Collectively, G2/M arrest, necrosis and autophagy appeared to cooperatively contribute to the synergistic cytotoxicity of AsIII and gamabufotalin. Given that p38 MAPK serves an essential role in promoting glioblastoma cell survival, developing a possible strategy composed of AsIII, gamabufotalin, and a p38 MAPK inhibitor may provide novel insight into approaches designed to combat glioblastoma.


Author(s):  
Jiesi Zhou ◽  
Krista Vincent ◽  
Scott Findlay ◽  
Daniel Choi ◽  
Roseline Godbout ◽  
...  

Glioblastoma is the most common and malignant brain tumor with a median overall survival of 20.5 months. There is an urgent need to develop novel therapeutic strategies. Using a glioblastoma TCGA dataset, we have determined that high NSUN5 mRNA expression is strongly associated with poor survival in glioblastoma patients. NSUN5 is a ribosomal RNA (rRNA) cytosine methyltransferase. Human NSUN5 is located in chromosome 7 and is completely deleted in the Williams-Beurren syndrome, a complex neurodevelopmental disorder. However, RNA targets of NSUN5 in mammals and its role in cancer are unknown. The objective of this project is to determine whether elevated NSUN5 changes rRNA methylation pattern and thereby leads to pro-tumorigenic translational reprogramming and pro-tumorigenic phenotypes in glioblastoma. Western blotting showed that NSUN5 is expressed in 7 out of 9 established glioblastoma cell lines and in 8 out of 12 primary patient-derived glioblastoma cell lines. Bisulfite sequencing confirmed that NSUN5 methylates C3782 of human 28S rRNA in glioblastoma cells. Functionally, overexpression of NSUN5 increases, whereas NSUN5 knockout decreases global protein synthesis and sphere formation in glioblastoma cells. More importantly, mice bearing intracranial NSUN5-expressing U87 tumors survived for a shorter time than mice bearing tumors derived from U87 control cells. Our results suggest that NSUN5 methylates 28S rRNA and may enhance cancer stem cell phenotypes and tumor formation and/or progression in glioblastoma. Experiments are ongoing to determine whether NSUN5 promotes tumor formation and/or progression through translational reprogramming in glioblastoma. This study may help identify novel therapeutic targets for glioblastoma.


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