Resistance to growth inhibition by transforming growth factor—β in malignant glioma cells with functional receptors

1998 ◽  
Vol 88 (3) ◽  
pp. 529-534 ◽  
Author(s):  
Shiro Isoe ◽  
Hirofumi Naganuma ◽  
Shin Nakano ◽  
Atsushi Sasaki ◽  
Eiji Satoh ◽  
...  
Keyword(s):  
Growth Inhibition ◽  
Malignant Glioma ◽  
Cell Lines ◽  
Glioma Cell ◽  
Glioma Cells ◽  
Content Type ◽  
Glioma Cell Lines ◽  
Malignant Glioma Cells ◽  
Tgf Β1 ◽  
Fine Print

Object. The aim of this study was to investigate the mechanism by which malignant glioma cells escape from growth inhibition mediated by transforming growth factor-β (TGF-β), a ubiquitous cytokine that inhibits cell proliferation by causing growth arrest in the G1 phase of the cell cycle. Methods. The authors measured the response of eight malignant glioma cell lines to the growth-inhibiting activity of TGF-β in vitro and the expression of TGF-β Types I and II receptors in malignant glioma cells. The effect of TGF-β on the expression of a p27Kip1 cyclin-dependent kinase inhibitor was also investigated to assess the downstream signal transmission from TGF-β receptors. All malignant glioma cell lines were insensitive to growth inhibition by TGF-β1 and TGF-β2. Analyses of TGF-β receptors by means of affinity labeling in which 125I-TGF-β1 was used showed that six glioma lines had both TGF-β Types I and II receptors on their cell surfaces, whereas two lines had very small amounts of TGF-β Type I and/or Type II receptors. Northern blot analysis showed that all tumor lines expressed variable levels of messenger RNAs for both TGF-β Types I and II receptors. Flow cytometric analyses revealed that treatment of malignant glioma cells with TGF-β1 significantly downregulated the expression of p27Kip1 protein in all malignant glioma cell lines except one. Conclusions. The authors suggest that most malignant glioma cells express TGF-β Types I and II receptors, which can transmit some signals downstream and that the loss of response to TGF-β growth inhibition may not be caused by an abnormality of the TGF-β receptors.

Differential effects of vincristine and phenytoin on the proliferation, migration, and invasion of human glioma cell lines

1995 ◽  
Vol 82 (6) ◽  
pp. 1035-1043 ◽  
Author(s):  
Jörg-Christian Tonn ◽  
Hans Kristian Haugland ◽  
Jaakko Saraste ◽  
Klaus Roosen ◽  
Ole Didrik Laerum
Keyword(s):  
Cell Lines ◽  
Glioma Cell ◽  
Glioma Cells ◽  
Migration And Invasion ◽  
Human Glioma ◽  
Human Glioma Cells ◽  
Content Type ◽  
Glioma Cell Lines ◽  
Dose Dependent ◽  
Fine Print

✓ The aim of this study was to investigate the antimigratory and antiinvasive potential of vincristine sulfate (VCR) on human glioma cells and to analyze whether phenytoin (5,5-diphenylhydantoin; DPH) might act synergistically with VCR. Vincristine affects the cytoplasmic microtubules; DPH has been reported to enhance VCR cytotoxicity in murine cells. In two human glioma cell lines, GaMG and D-37MG, we found VCR to reduce monolayer growth and colony formation in a dose-dependent fashion at concentrations of 10 ng/ml and above. Phenytoin increased the cytotoxic and cystostatic effects of VCR in monolayer cells but not in spheroids. Multicellular spheroids were used to investigate directional migration. A coculture system of GaMG and D-37MG spheroids with fetal rat brain aggregates was used to analyze and quantify tumor cell invasion. A dose-dependent inhibition of migration and invasion by VCR was observed in both cell lines without further enhancement by DPH. Immunofluorescence microscopy with antibodies against α-tubulin revealed dose-dependent morphological alterations in the microtubules when the cells were exposed to VCR but not after incubation with DPH. Based on the combination of standardized in vitro model systems currently in use and the present data, the authors strongly suggest that VCR inhibits migration and invasion of human glioma cells. This is not altered by DPH, which inhibits cell proliferation in combination with VCR.

Growth inhibition of human malignant glioma cells induced by the PI3-K—specific inhibitor

2003 ◽  
Vol 98 (1) ◽  
pp. 154-161 ◽  
Author(s):  
Takashi Shingu ◽  
Kazuo Yamada ◽  
Nobumasa Hara ◽  
Kouzo Moritake ◽  
Harumi Osago ◽  
...  
Keyword(s):  
Growth Inhibition ◽  
Malignant Glioma ◽  
Cell Lines ◽  
Akt Pathway ◽  
Content Type ◽  
Phosphorylated Akt ◽  
Human Malignant Glioma ◽  
The Status ◽  
Malignant Glioma Cells ◽  
Fine Print

Object. The phosphatase and tensin homolog deleted from chromosome 10 (PTEN) functions as a tumor suppressor by negatively regulating the growth/survival signals of the phosphatidylinositol 3-kinase (PI3-K)/Akt pathway. The PI3-K/Akt pathway in PTEN-deficient tumors may be one of the key targets for anticancer therapy. The authors examined the effects of the PI3-K inhibitor 2-(4-morpholinyl)-8-phenylchromone (LY294002) on human malignant glioma cells, and compared these effects on PTEN-deficient cells with those on PTEN—wild-type (PTEN-wt) cells. Methods. Using human malignant glioma cell lines, including the PTEN-deficient cells A172 and U87MG and the PTEN-wt cells LN18 and LN229, the effects of LY294002 on cell growth, apoptosis, and chemotherapeutic agent—induced cytotoxicity were evaluated. The LY294002 inhibited the growth of U87MG cells associated with reduced phosphatidylinositol 3,4,5,-trisphosphate and phosphorylated Akt, and also induced growth inhibition in three other cell lines. Although LY294002 caused apoptosis in all four cell lines, apoptosis seemed to contribute to only a small portion of growth inhibition induced by LY294002. There was no link between the status of PTEN and the median inhibitory concentration values for LY294002 or between the gene status and the extent of LY294002-induced apoptosis. The LY294002 significantly augmented the cytotoxicity induced by etoposide in PTEN-deficient cells, but not in PTEN-wt cells. Enhancement of 1,3-bis(2-chloroethyl)-1-nitrosourea— and cisplatin-induced cytotoxicity by LY294002 was not linked to the status of PTEN. No marked difference in the amounts of phosphorylated Akt was found between PTEN-deficient and PTEN-wt cells. Conclusions. The findings show that PI3-K is a possible target for therapy in patients with gliomas, and PI3-K inhibitors in combination with chemotherapeutic agents could be potent therapeutic modalities for patients with malignant gliomas.

Isolation and characterization of human malignant glioma cells from histologically normal brain

1997 ◽  
Vol 86 (3) ◽  
pp. 525-531 ◽  
Author(s):  
Daniel L. Silbergeld ◽  
Michael R. Chicoine
Keyword(s):  
Malignant Glioma ◽  
Cell Lines ◽  
Growth Rates ◽  
Glioma Cells ◽  
Normal Brain ◽  
Content Type ◽  
Human Malignant Glioma ◽  
Malignant Glioma Cells ◽  
Fine Print ◽  
Neuropathological Evaluation

✓ Brain invasion prevents complete surgical extirpation of malignant gliomas; however, invasive cells from distant, histologically normal brain previously have not been isolated, cultured, and characterized. To evaluate invasive human malignant glioma cells, the authors established cultures from gross tumor and histologically normal brain. Three men and one woman, with a mean age of 67 years, underwent two frontal and two temporal lobectomies for tumors, which yielded specimens of both gross tumor and histologically normal brain. Each specimen was acquired a minimum of 4 cm from the gross tumor. The specimens were split: a portion was sent for neuropathological evaluation (three glioblastomas multiforme and one oligodendroglioma) and a portion was used to establish cell lines. Morphologically, the specimens of gross tumor and histologically normal brain were identical in three of the four cell culture pairs. Histochemical staining characteristics were consistent both within each pair and when compared with the specimens sent for neuropathological evaluation. Cultures demonstrated anchorage-independent growth in soft agarose and neoplastic karyotypes. Growth rates in culture were greater for histologically normal brain than for gross tumor in three of the four culture pairs. Although the observed increases in growth rates of histologically normal brain cultures do not correlate with in vivo behavior, these findings corroborate the previously reported stem cell potential of invasive glioma cells. Using the radial dish assay, no significant differences in motility between cultures of gross tumor and histologically normal brain were found. In summary, tumor cells were cultured from histologically normal brain acquired from a distance greater than 4 cm from the gross tumor, indicating the relative insensitivity of standard histopathological identification of invasive glioma cells (and hence the inadequacy of frozen-section evaluation of resection margins). Cell lines derived from gross tumor and histologically normal brain were usually histologically identical and demonstrated equivalent motility, but had different growth rates.

Antiproliferative effect of trapidil, a platelet-derived growth factor antagonist, on a glioma cell line in vitro

1990 ◽  
Vol 73 (3) ◽  
pp. 436-440 ◽  
Author(s):  
Jun-ichi Kuratsu ◽  
Yukitaka Ushio
Keyword(s):  
Growth Factor ◽  
Cell Lines ◽  
Glioma Cell ◽  
Glioma Cells ◽  
Inhibitory Effect ◽  
Platelet Derived Growth Factor ◽  
Content Type ◽  
Glioma Cell Lines ◽  
Fine Print

✓ Platelet-derived growth factor (PDGF) is produced by glioma cells. However, there is heterogeneity among glioma cell lines in the production of PDGF. It has been demonstrated that U251MG cells produce a PDGF-like molecule while U105MG cells do not. Trapidil, a specific antagonist of PDGF, competes for receptor binding with PDGF. Therefore, the inhibitory effect of trapidil on the proliferation of glioma cells was investigated in vitro using two glioma cell lines. At 100 µg/ml, trapidil significantly inhibited the proliferation of U251MG cells (which produce the PDGF-like molecule). At the same trapidil concentration, the proliferation of U105MG cells (which do not produce the PDGF-like molecule) was not inhibited. The inhibitory effect of trapidil was remarkable on Days 3 and 4 of culture. After 4 days of incubation, the proliferation of U251MG cells was 46% of the control preparation. Trapidil enhanced the antitumor effect of 3-((4-amino-2-methyl-5-pyrimidinyl)ethyl)-1-(2-chloroethyl)-1-nitro-sourea (ACNU) against U251MG cells. The enhancing effect was highest on Days 4 and 6 of culture. After 6 days of incubation in the presence of 100 µg/ml trapidil and 1 µg/ml ACNU, the proliferation of U251MG cells was 18% of the control preparation. These findings suggest that trapidil interrupts the autocrine loop at the PDGF and PDGF-receptor level and that combination therapy with trapidil and ACNU may be useful in the treatment of glioma.

Participation of an abnormality in the transforming growth factor–β signaling pathway in resistance of malignant glioma cells to growth inhibition induced by that factor

2006 ◽  
Vol 105 (1) ◽  
pp. 119-128 ◽  
Author(s):  
Lei Zhang ◽  
Eiji Sato ◽  
Kenichi Amagasaki ◽  
Atsuhito Nakao ◽  
Hirofumi Naganuma
Keyword(s):  
Growth Inhibition ◽  
Malignant Glioma ◽  
Cell Line ◽  
Cell Lines ◽  
A549 Cell ◽  
Glioma Cell ◽  
Nuclear Translocation ◽  
A549 Cell Line ◽  
Glioma Cell Lines ◽  
Malignant Glioma Cells

Object Malignant glioma cells secrete and activate transforming growth factor–β (TGFβ) and are resistant to growth inhibition by that factor. Nevertheless, the mechanism underlying this effect remains poorly understood. In this study, the mechanism of the resistance to growth inhibition induced by TGFβ was investigated. Methods The authors examined the expression of downstream components of the TGFβ receptor, including Smad2, Smad3, Smad4, and Smad7, and the effect of TGFβ1 treatment on the phosphorylation of Smad2 and the nuclear translocation of Smad2 and Smad3 by using 10 glioma cell lines and the A549 cell line, which is sensitive to TGFβ-mediated growth inhibition. The expression of two transcriptional corepressor proteins, SnoN and Ski, and the effect of TGFβ1 treatment on the expression of the SnoN protein and the cell cycle regulators p21, p15, cyclin-dependent kinase–4 (CDK4), and cyclin D1 were also examined. Expression of the Smad2 and Smad3 proteins was lower in the glioma cell lines than in the A549 cell line and in normal astrocytes. In particular, Smad3 expression was low or very low in nine of the 10 malignant glioma cell lines. Expression of Smad4 was low in four glioma cell lines, and expression of the Smad7 protein was similar when compared with protein expression in the A549 cell line and in normal astrocytes. The levels of Smad2 phosphorylation after TGFβ1 treatment were lower in glioma cell lines than in the A549 cell line, except for one glioma cell line. Seven of the 10 glioma cell lines exhibited lower levels of nuclear translocation of Smad2 and Smad3, and two cell lines that expressed very low levels of Smad3 protein showed no nuclear translocation. All glioma cell lines expressed the SnoN protein and its expression was unaltered by treatment with TGFβ1. Three glioma cell lines expressed high levels of the Ski protein. The expression of the p21cip1, p15INK4B, CDK4, and cyclin D1 proteins was not altered by TGFβ1 treatment, except in one cell line that displayed a slight increase in p21 protein. Overall, the expression of the Smad2 and Smad3 proteins was low in the glioma cell lines, the phosphorylation and nuclear translocation of Smad2 and Smad3 were impaired, and the TGFβ receptor signal did not affect the expression of the SnoN, p21, p15, cyclin D1, and CDK4 proteins. Conclusions These results suggest that the ability to resist TGFβ-mediated growth inhibition in malignant glioma cells is due to abnormalities in the TGFβ signaling pathway.

Induction of reactive oxygen intermediates—dependent programmed cell death in human malignant ex vivo glioma cells and inhibition of the vascular endothelial growth factor production by taurolidine

2005 ◽  
Vol 102 (6) ◽  
pp. 1055-1068 ◽  
Author(s):  
Roksana Rodak ◽  
Hisashi Kubota ◽  
Hideyuki Ishihara ◽  
Hans-Pietro Eugster ◽  
Dilek Könü ◽  
...  
Keyword(s):  
Vascular Endothelial Growth Factor ◽  
Cell Death ◽  
Cell Lines ◽  
Glioma Cell ◽  
Ex Vivo ◽  
Vascular Endothelial ◽  
Content Type ◽  
Glioma Cell Lines ◽  
Endothelial Growth Factor ◽  
Fine Print

Object. Taurolidine, a derivative of the amino acid taurin, was recently found to display a potent antineoplastic effect both in vitro and in vivo. The authors therefore initiated studies to assess the potential antineoplastic activity of taurolidine in human glioma cell lines and in ex vivo malignant cell cultures. They also studied the mechanisms that induce cell death and the impact of taurolidine on tumor-derived vascular endothelial growth factor (VEGF) production. Methods. Cytotoxicity and clonogenic assays were performed using crystal violet staining. In the cytotoxicity assay 100% of glioma cell lines (eight of eight) and 74% of ex vivo glioma cultures (14 of 19) demonstrated sensitivity to taurolidine, with a mean median effective concentration (EC50) of 51 ± 28 µg/ml and 56 ± 23 µg/ml, respectively. Colony formation was inhibited by taurolidine, with a mean EC50 of 7 ± 3 µg/ml for the cell lines and a mean EC50 of 3.5 ± 1.7 µg/ml for the ex vivo glioma cultures. On observing this high activity of taurolidine in both assays, the authors decided to evaluate its cell death mechanisms. Fragmentation of DNA, externalization of phosphatidylserine, activation of poly(adenosine diphosphate—ribose) polymerase, loss of the mitochondrial membrane potential followed by a release of apoptosis-inducing factor, and typical apoptotic features were found after taurolidine treatment. Cell death was preceded by the generation of reactive O2 intermediates, which was abrogated by N-acetylcysteine but not by benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone. Moreover, taurolidine also induced suppression of VEGF production on the protein and messenger RNA level, as shown by an enzyme-linked immunosorbent assay and by reverse transcription—polymerase chain reaction. Conclusions. Given all these findings, taurolidine may be a promising new agent in the treatment of malignant gliomas; it displays a combination of antineoplastic and antiangiogenic activities, inducing tumor cell apoptosis and inhibiting tumor-derived VEGF production.

Molecular determinants of glioma cell migration and invasion

2001 ◽  
Vol 94 (6) ◽  
pp. 978-984 ◽  
Author(s):  
Christine Wild-Bode ◽  
Michael Weller ◽  
Wolfgang Wick
Keyword(s):  
Cell Lines ◽  
Cell Invasion ◽  
Glioma Cell ◽  
Growth Patterns ◽  
Migration And Invasion ◽  
Integrin Expression ◽  
Content Type ◽  
Expression Levels ◽  
Glioma Cell Lines ◽  
Fine Print

Object. Migration and invasion are important prerequisites for the infiltrative and destructive growth patterns of malignant gliomas. Infiltrative growth prevents complete tumor resection and causes significant neurological morbidity and mortality. Methods. The authors assessed the expression of matrix metalloproteinases (MMPs) at messenger RNA and protein levels, MMP-2 and MMP-9 activities, and expression levels of a panel of anti- and proapoptotic proteins of the BCL-2 family. They then correlated their findings with αVβ3 integrin expression and the migratory and invasive potentials in 12 human malignant glioma cell lines. Multiple MMPs were expressed by most cell lines. The levels of MMP-2 and MMP-3 and the activities of MMP-2 and MMP-9 correlated with tumor cell invasion. Migration and invasion were also correlated. Although the expression levels of αVβ3 integrin did not predict migration or invasion, a neutralizing αVβ3 integrin antibody inhibited migration and invasion selectively in cell lines that contained a high level of αVβ3 integrin expression, thus indicating the important role of αVβ3 integrin for migration and invasion in this subset of cell lines. An expression pattern of BCL-2 family proteins that favor resistance to apoptosis was associated with enhanced migration, invasion, and MMP activity. Wild-type p53 cell lines migrated farther than mutant p53 cell lines. Conclusions. Activities of MMP-2 and MMP-9 are the best predictors of glioma cell invasion. The αVβ3 integrin mediates migration and invasion in a subset of glioma cell lines, but these processes do not depend on αVβ3 integrin expression. Antiapoptotic BCL-2 family protein expression is a predictor of efficient migration and invasion.

Interaction between p53 and p16 expressed by adenoviral vectors in human malignant glioma cell lines

2002 ◽  
Vol 97 (1) ◽  
pp. 143-150 ◽  
Author(s):  
Seung-Ki Kim ◽  
Kyu-Chang Wang ◽  
Byung-Kyu Cho ◽  
Hyun-Tai Chung ◽  
Young-Yim Kim ◽  
...  
Keyword(s):  
Cell Lines ◽  
Western Blotting ◽  
Glioma Cell ◽  
Malignant Gliomas ◽  
G1 Arrest ◽  
Moderate Degree ◽  
Wild Type ◽  
Content Type ◽  
Glioma Cell Lines ◽  
Fine Print

Object. Multiple gene replacements have been examined as a potential treatment modality for malignant gliomas. Nevertheless, no reports are available that detail the synergy, additivity, or antagonism of multiple genes. The aim of this study was to assess the interaction between p53 and p16 genes in the growth of glioma cell lines. Methods. The human glioma cell lines U87MG and U373MG were transduced using an adenoviral vector with Ad-p53, Ad-p16, or both. Western blotting was performed to determine the expression of the protein products of the transduced p53 and p16 genes. To establish whether the combination of Ad-p53 and Ad-p16 would be beneficial, the effects of gene combinations at the median inhibitory concentration level were analyzed using the isobologram method. Annexin assays and cell cycle analyses were performed on the transduced cells. Western blotting demonstrated the expression of p53 and p16 in transduced cells. Simultaneous exposure to Ad-p53 and Ad-p16 produced additive effects in both glioma cell lines. Experimental data points in U373MG lay near the Mode I line, indicating that the vectors had a different mode of action. The restoration of normal p53-encoded protein in the mutant cell lines induced apoptosis, whereas in the wild-type p53 cell lines, the overexpression of wild-type p53 resulted in a moderate degree of apoptosis and G1 arrest. Furthermore, Ad-p16 induced more marked G1 arrest than Ad-p53 in cells with wild-type p53. Conclusions. The results show that interaction between Ad-p53 and Ad-p16 is additive, regardless of p53 gene status.

Enhanced radiosensitivity of malignant glioma cells after adenoviral p53 transduction

1999 ◽  
Vol 91 (6) ◽  
pp. 997-1004 ◽  
Author(s):  
William C. Broaddus ◽  
Yue Liu ◽  
Laura L. Steele ◽  
George T. Gillies ◽  
Peck-Sun Lin ◽  
...  
Keyword(s):  
Malignant Glioma ◽  
Glioma Cells ◽  
Terminal Deoxynucleotidyl Transferase ◽  
Wild Type ◽  
Content Type ◽  
Cranial Radiation ◽  
Adenoviral Transduction ◽  
Wild Type P53 ◽  
Malignant Glioma Cells ◽  
Fine Print

Object. The goal of this study was to determine whether adenoviral vector—mediated expression of human wildtype p53 can enhance the radiosensitivity of malignant glioma cells that express native wild-type p53.The p53 gene is thought to function abnormally in the majority of malignant gliomas, although it has been demonstrated to be mutated in only approximately 30%. This has led to studies in which adenoviral transduction with wild-type human p53 has been investigated in an attempt to slow tumor cell growth. Recent studies suggest that reconstitution of wild-type p53 can render cells more susceptible to radiation-mediated death, primarily by p53-mediated apoptosis.Methods. Rat RT2 glioma cells were analyzed for native p53 status by reverse transcriptase—polymerase chain reaction and sequence analysis and for p53 expression by Western blot analysis. Clonogenic survival and the terminal deoxynucleotidyl transferase—mediated deoxyuridine triphosphate nick-end labeling assay were used to characterize RT2 cell radiosensitivity and apoptosis, respectively, with and without prior transduction with p53-containing and control adenoviral vectors. Animal survival length was monitored after intracerebral implantation with transduced and nontransduced RT2 cells, with and without cranial radiation.The RT2 cells were demonstrated to express native rat wild-type p53 and to markedly overexpress human p53 following adenoviral p53 transduction. The combination of p53 transduction followed by radiation resulted in marked decreases in RT2 cell survival and increases in apoptosis at radiation doses from 2 to 6 Gy. Animals receiving cranial radiation after intracerebral implantation with RT2 cells previously transduced with p53 survived significantly longer than control animals (p < 0.01).Conclusions. The ability to enhance the radiosensitivity of malignant glioma cells that express wild-type p53 by using adenoviral transduction to induce overexpression of p53 offers hope for this approach as a therapeutic strategy, not only in human gliomas that express mutant p53, but also in those that express wild-type p53.

Motility factor produced by malignant glioma cells: role in tumor invasion

1990 ◽  
Vol 73 (6) ◽  
pp. 881-888 ◽  
Author(s):  
Takanori Ohnishi ◽  
Norio Arita ◽  
Toru Hayakawa ◽  
Shuichi Izumoto ◽  
Takuyu Taki ◽  
...  
Keyword(s):  
Cell Migration ◽  
Malignant Glioma ◽  
Tumor Invasion ◽  
Cytochalasin B ◽  
Glioma Cells ◽  
Actin Microfilaments ◽  
Content Type ◽  
Motility Factor ◽  
Malignant Glioma Cells ◽  
Fine Print

✓ To better understand the cellular mechanism of tumor invasion, the production of a cell motility-stimulating factor by malignant glioma cells was studied in vitro. Serum-free conditioned media from cultures of rat C6 and human T98G cell lines contained a factor that stimulated the locomotion of the producer cells. This factor was termed the “glioma-derived motility factor.” The glioma-derived motility factor is a heat-labile protein with a molecular weight greater than 10 kD and has relative stability to acid. The factor showed not only chemotactic activity but also chemokinetic (stimulated random locomotion) activity in the two types of glioma cells studied. Although glioma-derived motility factors in conditioned media obtained from two different cell origins are likely to be the same, chemokinetic migration of T98G cells to their conditioned medium was much stronger than that of C6 cells to theirs. Coincubation of cells with cytochalasin B, which disrupts the assembly of cellular actin microfilaments, almost completely inhibited the cell migration stimulated by glioma-derived motility factor. Cytochalasin B also induced marked alterations in cell morphology, including cell retraction and arborization, while the drug did not affect cell attachment to culture dishes. These results indicate that glioma cells produce a motility factor which may play a role particularly when tumor cells are detached and migrate away from the original tumor mass, thus promoting tumor invasion. Also, glioma cell migration stimulated by the motility factor requires the normal organization of cytoskeletons such as actin microfilaments.

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