DDRE-38. MAGMAS INHIBITION IN MEDULLOBLASTOMA CELL CULTURES AND PATIENT-DERIVED XENOGRAFT MODELS: POTENTIAL THERAPEUTIC IMPLICATIONS

2021 ◽  
Vol 23 (Supplement_6) ◽  
pp. vi82-vi82
Author(s):  
Clay Hoerig ◽  
Ashley Plant-Fox ◽  
Javier Lepe ◽  
Christopher Douglas ◽  
Naomi Lomeli ◽  
...  
Keyword(s):  
Cell Lines ◽  
Cell Cultures ◽  
Primary Cultures ◽  
Common Type ◽  
Prognostic Features ◽  
Medulloblastoma Cell ◽  
Patient Derived Xenograft ◽  
Xenograft Models ◽  
Medulloblastoma Cell Lines

Abstract BACKGROUND Brain tumors are the second most common type of pediatric cancer and are the leading cause of all cancer-related deaths in children. Medulloblastoma (MB) is the most common type of malignant pediatric brain tumor and has a five-year overall survival ranging from 40-75%, depending on the patient’s age and other prognostic features. There are current anti-cancer therapies against medulloblastoma, but the treatment of recurrent disease remains a challenge. Magmas (mitochondria-associated protein involved in granulocyte-macrophage colony-stimulating factor signal transduction) overexpression has been reported in multiple types of metabolically active tissue and cancer cells, including prostate cancer, pituitary adenoma, and glioma. Limited data suggest that specific subgroups of medulloblastoma may also overexpress Magmas. This study aims to examine whether Magmas inhibition by compound “BT#9” could be beneficial for the treatment of medulloblastoma. METHODS We studied the ability of a Magmas inhibitor (BT#9) as a therapeutic agent in stable medulloblastoma cell lines (DAOY and D283) and patient-derived primary cultures with MTT assays, migration assays, and invasion assays. RESULTS Similar to the adult GBM studies, Magmas inhibition by BT9 had significant cytotoxic effects, causing both decreased cell proliferation and blocked cell migration in medulloblastoma cell lines DAOY and D283. IC50s determined for each during different time points demonstrated an average range of less than 3μM compared to the average range seen in adult glioblastoma cell cultures (< 10 μM). These findings suggest that the inhibition of Magmas warrants further investigation as a potential therapeutic target to optimize clinical outcomes in medulloblastoma. Our future studies will include the determination of IC50s for primary cell cultures and in vitro testing with patient-derived xenograft models.

scholarly journals Mevalonate Prevents Lovastatin-Induced Apoptosis in Medulloblastoma Cell Lines

1999 ◽  
Vol 26 (4) ◽  
pp. 305-310 ◽  
Author(s):  
Wei Wang ◽  
Robert J.B. Macaulay
Keyword(s):  
Cell Lines ◽  
Mevalonate Pathway ◽  
Critical Duration ◽  
Northern Analysis ◽  
Hmg Coa Reductase ◽  
Medulloblastoma Cell ◽  
Induced Apoptosis ◽  
Coa Reductase ◽  
Medulloblastoma Cell Lines

Background:3-hydroxy-3-methylglutaryl coenzyme A reductase (HMG-CoA reductase) is a key rate-limiting enzyme in the mevalonate pathway, which generates precursors for cholesterol biosynthesis and the production of non-steroidal mevalonate derivatives that are involved in a number of growth-regulatory processes. We have reported that lovastatin, a competitive inhibitor of HMG-CoA reductase, not only inhibits medulloblastoma proliferationin vitro, but also induces near-complete cell death via apoptosis. The present study explores some of the pathways which may be involved in lovastatin-induced apoptosis.Methods:Medulloblastoma cell lines were exposedin vitroto lovastatin with or without mevalonate, and document the effects using morphology, flow cytometry, DNA electrophoresis and Northern analysis.Results:1) Mevalonate prevents apoptosis when co-incubated with lovastatin, or when administered to lovastatin-pretreated cells. 2) Mevalonate restores the lovastatin-arrested cell cycle, allowing S phase entry. 3) Mevalonate does not prevent lovastatin-induced apoptosis after a critical duration of lovastatin pretreatment. For cell lines Daoy and UW228 this was 24 hours, and for D283 Med and D341 Med it was 48 hours. 4) Increases in HMG-CoA reductase mRNA levels induced by lovastatin are abrogated by co-incubation with lovastatin and mevalonate.Conclusion:These results confirm that lovastatin inhibition of this enzyme results in blockage of the mevalonate pathway, and that such a block is a critical step in the mechanism of lovastatin-induced apoptosis.

scholarly journals Characterization of G-CSF receptor expression in medulloblastoma

2020 ◽  
Vol 2 (1) ◽  
Author(s):  
Megan Rose Paul ◽  
Yuchen Huo ◽  
Andrea Liu ◽  
Jacqueline Lesperance ◽  
Alexandra Garancher ◽  
...  
Keyword(s):  
Flow Cytometry ◽  
Cell Lines ◽  
Growth Rates ◽  
Expression Profiles ◽  
Gene Expression Profiles ◽  
Receptor Expression ◽  
Medulloblastoma Cell ◽  
Potential Marker ◽  
Medulloblastoma Cell Lines

Abstract Background Identifying mechanisms of medulloblastoma recurrence is a key to improving patient survival, and targeting treatment-resistant subpopulations within tumors could reduce disease recurrence. Expression of the granulocyte colony-stimulating factor receptor (G-CSF-R, CD114) is a potential marker of cancer stem cells, and therefore we hypothesized that a subpopulation of medulloblastoma cells would also express CD114 and would demonstrate chemoresistance and responsiveness to G-CSF. Methods Prevalence of CD114-positive (CD114+) cells in medulloblastoma cell lines, patient-derived xenograft (PDX) tumors, and primary patient tumor samples were assessed by flow cytometry. Growth rates, chemoresistance, and responses to G-CSF of CD114+ and CD114-negative (CD114−) cells were characterized in vitro using continuous live cell imaging and flow cytometry. Gene expression profiles were compared between CD114+ and CD114− medulloblastoma cells using quantitative RT-PCR. Results CD114+ cells were identifiable in medulloblastoma cell lines, PDX tumors, and primary patient tumors and have slower growth rates than CD114− or mixed populations. G-CSF accelerates the growth of CD114+ cells, and CD114+ cells are more chemoresistant. The CD114+ population is enriched when G-CSF treatment follows chemotherapy. The CD114+ population also has higher expression of the CSF3R, NRP-1, TWIST1, and MYCN genes. Conclusions Our data demonstrate that a subpopulation of CD114+ medulloblastoma cells exists in cell lines and tumors, which may evade traditional chemotherapy and respond to exogenous G-CSF. These properties invite further investigation into the role of G-CSF in medulloblastoma therapy and methods to specifically target these cells.

scholarly journals Cell-Cycle Gene Expression in Lovastatin-Induced Medulloblastoma Apoptosis

2003 ◽  
Vol 30 (4) ◽  
pp. 349-357 ◽  
Author(s):  
Wei Wang ◽  
Robert J.B. Macaulay
Keyword(s):  
Gene Expression ◽  
Cell Cycle ◽  
Cell Lines ◽  
Hmg Coa Reductase ◽  
Medulloblastoma Cell ◽  
Coa Reductase ◽  
Lovastatin Treatment ◽  
Medulloblastoma Cell Lines ◽  
Gene Mrna

Background:3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase is a key rate-limiting enzyme in the mevalonate pathway, which generates precursors both for cholesterol biosynthesis and for the production of nonsteroidal mevalonate derivatives that are involved in a number of growth-regulatory processes. We have reported that lovastatin, a competitive inhibitor of HMG-CoA reductase, not only inhibits medulloblastoma proliferation in vitro, but also induces near-complete cell death via apoptosis. The mechanism of this phenomenon is unclear. Possible involvement of changes in expression of certain cell-cycle related genes led us to study some of them in more detail.Methods:Medulloblastoma cell lines were exposed in vitro to lovastatin, and the effects of gene expression changes were studied using RT-PCR, antisense oligonucleotide, DNA electrophoresis and Western blotting analysis.Results:1) Levels of total Ras gene mRNA and individual Ras gene mRNA are stable in lovastatin treatment in all examined medulloblastoma cell lines. 2) Blocking c-myc gene over-expression does not enhance medulloblastoma cell sensitivity to lovastatin. 3) Following lovastatin treatment, p16 expression exhibits no change, but pronounced increases of p27KIP1 protein are observed in all examined cell lines. Lovastatin induces pronounced increases of p21WAF1 protein only in Daoy and UW228, but not in D283 Med and D341 Med. 4) Following lovastatin treatment, increased p53 protein is detected only in D341 Med, and bax protein is unchanged in all cell lines.Conclusion:Lovastatin-induced growth inhibition and apoptosis in medulloblastoma are not dependent on the regulation of Ras and c-myc gene expression, but may be mediated by p27KIP1 gene expression. Lovastatin-induced apoptosis in medulloblastoma is probably p53 independent, but p53 and p21WAF1 gene expression may also mediate anti-proliferative effects of lovastatin on specific medulloblastoma cell lines.

Hepatoma Cell Cultures as In Vitro Models for the Hepatotoxicity of Xenobiotics

1988 ◽  
Vol 16 (1) ◽  
pp. 32-37
Author(s):  
Margherita Ferro ◽  
Anna Maria Bassi ◽  
Giorgio Nanni
Keyword(s):  
Cell Lines ◽  
Cell Cultures ◽  
Membrane Lipids ◽  
Hepatoma Cell ◽  
Positive Control ◽  
In Vitro Models ◽  
Low Concentrations ◽  
Formation Efficiency ◽  
Dose Dependent

Two hepatoma cell cultures were examined as in vitro models to be used in genotoxicity and cytotoxicity tests without the addition of bioactivating enzymes. The MH1C1, and HTC hepatoma lines were used in this study to establish their sensitivity to a number of xenobiotics, namely, cyclophosphamide (CP), the classical positive control in bioactivation tests; benzaldehyde (BA), a short-chain aldehyde; and 4-hydroxynonenal (HNE), a major toxic end-product of the peroxidative degradation of cell membrane lipids. As a first approach, we compared the following cytotoxicity tests: release of lactate dehydrogenase (LDH), and colony formation efficiency (CF). Colony-forming cells were exposed to the drugs according to different procedures, before or after the anchorage phase. The leakage of LDH into the medium following exposure of both cell lines to HNE, CP and BA for up to 24 hours was found not to be a good index of cytotoxicity. A better indicator of cytotoxicity was CF, as evaluated by exposure of the cells 24 hours after seeding. The effects were detectable at very low concentrations, corresponding to 10, 90 and 100μM for HNE, CP and BA, respectively. The impairment of CF efficiency was dose-dependent and time-dependent, and several differences between the two cell lines were observed.

Inhibition of Aurora Kinase A enhances chemosensitivity of medulloblastoma cell lines

2010 ◽  
Vol 55 (1) ◽  
pp. 35-41 ◽  
Author(s):  
Ayman El-Sheikh ◽  
Rong Fan ◽  
Diane Birks ◽  
Andrew Donson ◽  
Nicholas K Foreman ◽  
...  
Keyword(s):  
Cell Lines ◽  
Aurora Kinase ◽  
Aurora Kinase A ◽  
Medulloblastoma Cell ◽  
Kinase A ◽  
Medulloblastoma Cell Lines

Phenotypic Analysis of Four Human Medulloblastoma Cell Lines and Transplantable Xenografts

1989 ◽  
Vol 48 (1) ◽  
pp. 48-68 ◽  
Author(s):  
Xuanmin He ◽  
Stephen X. Skapek ◽  
Carol J. Wikstrand ◽  
Henry S. Friedman ◽  
John Q. Trojanowski ◽  
...  
Keyword(s):  
Cell Lines ◽  
Phenotypic Analysis ◽  
Medulloblastoma Cell ◽  
Human Medulloblastoma ◽  
Medulloblastoma Cell Lines

scholarly journals Therapeutic evaluation of palbociclib and its compatibility with other chemotherapies for primary and recurrent nasopharyngeal carcinoma

2020 ◽  
Author(s):  
zhichao xue ◽  
Vivian Wai Yan Lui ◽  
Yongshu Li ◽  
Jia Lin ◽  
Chanping You ◽  
...  
Keyword(s):  
Cell Death ◽  
Nasopharyngeal Carcinoma ◽  
Cell Lines ◽  
Chemotherapeutic Drugs ◽  
Induce Cell Cycle Arrest ◽  
Ki 67 ◽  
Concurrent Treatment ◽  
Xenograft Models

Abstract Background: Recent genomic analyses revealed that druggable molecule targets were detectable in approximately 6% of patients with nasopharyngeal carcinoma (NPC). However, a dependency on dysregulated CDK4/6–cyclinD1 pathway signaling is an essential event in the pathogenesis of NPC. In this study, we aimed to evaluate the therapeutic efficacy of a specific CDK4/6 inhibitor, palbociclib, and its compatibility with other chemotherapeutic drugs for the treatment of NPC by using newly established xenograft models and cell lines derived from primary, recurrent, and metastatic NPC. Methods: We evaluated the efficacies of palbociclib monotherapy and concurrent treatment with palbociclib and cisplatin or suberanilohydroxamic acid (SAHA) in NPC cell lines and xenograft models. RNA sequencing was then used to profile the drug response–related pathways. Palbociclib-resistant NPC cell lines were established to determine the potential use of cisplatin as a second-line treatment after the development of palbociclib resistance. We further examined the efficacy of palbociclib treatment against cisplatin-resistant NPC cells. Results: In NPC cells, palbociclib monotherapy was confirmed to induce cell cycle arrest in the G1 phase in vitro . Palbociclib monotherapy also had significant inhibitory effects in all six tested NPC tumor models in vivo , as indicated by substantial reductions in the total tumor volumes and in Ki-67 proliferation marker expression. In NPC cells, concurrent palbociclib treatment mitigated the cytotoxic effect of cisplatin in vitro . Notably, concurrent treatment with palbociclib and SAHA synergistically promoted NPC cell death both in vitro and in vivo . This combination also further inhibited tumor growth by inducing autophagy-associated cell death. NPC cell lines with induced palbociclib or cisplatin resistance remained sensitive to treatment with cisplatin or palbociclib, respectively. Conclusions: Our study findings provide essential support for the use of palbociclib as an alternative therapy for NPC and increase awareness of the effective timing of palbociclib administration with other chemotherapeutic drugs. Our results provide a foundation for the design of first-in-human clinical trials of palbociclib regimens in patients with NPC.

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