Project description:Glioblastoma multiforme is the most common and most aggressive type of primary brain tumor. The brain-infiltrative character of glioblastoma makes complete surgical removal of the tumor impossible and neither radiation nor current chemotherapy provide cure. Recent evidence shows that glioblastoma multiforme consists of heterogeneous cell populations which differ in tumor-forming potential. Enriched tumor-initiating capacity has been linked to poorly differentiated glioblastoma cells sharing features with neural stem cells. Thus, these cells are important targets for new therapeutic strategies. We aim to identify novel targets controlling maintenance and differentiation in glioblastoma-initiating cells through high throughput screening. To this end, we utilized libraries of small chemical compounds and small interference RNAs in combination with automated imaging and data analysis. Patient-derived glioblastoma cells were expanded and characterized using neural stem cell conditions. In culture, the cells showed low differentiation but expression of neural stem cell markers such as Nestin and Sox2. Upon intracranial injection into SCID mice these cells gave rise to tumors displaying the hallmarks of the human disease. Differentiation of glioblastoma-initiating cells (for example elicited through bone morphogenetic protein, BMP) was associated with strong morphological changes. Hence, cellular morphology, as well as markers specific for differentiation or death were used as screen readout. Lentiviral RNA interference-based screening yielded several gene knockdowns leading to ‘forced’ differentiation of glioblastoma-initiating cells. For example, knockdown of TRRAP (transformation/transcription domain associated protein) led to strongly increased differentiation and loss of proliferative and self-renewing capacity in these cells. TRRAP is an adapter protein implicated in oncogenic transformation through c-MYC transcription activation, also participating in chromatin remodeling and DNA repair. Glioblastoma-initiating cells with reduced TRRAP displayed increased apoptosis upon treatment with the genotoxic agent temozolomide. In vivo, Trapp knockdown cells were not able to give rise to glioblastoma upon transplantation into the brain of SCID mice. Together, these findings support a crucial role for TRRAP in maintenance and tumorigenicity of glioblastoma-initiating cells and might offer future therapeutic options. Two treatments compared to control: two different shRNA sequences for TRRAP were compared to a control shRNA sequence in their effects on global transcription in brain tumor initiating cells
Project description:The paper describes a model of glioblastoma.
Created by COPASI 4.25 (Build 207)
This model is described in the article:
Modeling the Treatment of Glioblastoma Multiforme and Cancer Stem Cells with Ordinary Differential Equations
Kristen Abernathy and Jeremy Burke BMC
Computational and Mathematical Methods in Medicine Volume 2016, Article ID 1239861, 11 pages
Abstract:
Despite improvements in cancer therapy and treatments, tumor recurrence is a common event in cancer patients. One explanation of recurrence is that cancer therapy focuses on treatment of tumor cells and does not eradicate cancer stem cells (CSCs). CSCs are postulated to behave similar to normal stem cells in that their role is to maintain homeostasis. That is, when the population of tumor cells is reduced or depleted by treatment, CSCs will repopulate the tumor, causing recurrence. In this paper, we study the application of the CSC Hypothesis to the treatment of glioblastoma multiforme by immunotherapy. We extend the work of Kogan et al. (2008) to incorporate the dynamics of CSCs, prove the existence of a recurrence state, and provide an analysis of possible cancerous states and their dependence on treatment levels.
To cite BioModels Database, please use: BioModels Database: An enhanced, curated and annotated resource for published quantitative kinetic models .
To the extent possible under law, all copyright and related or neighbouring rights to this encoded model have been dedicated to the public domain worldwide.
Please refer to CC0 Public Domain Dedication for more information.
Project description:Glioblastoma multiforme is the most common and most aggressive type of primary brain tumor. The brain-infiltrative character of glioblastoma makes complete surgical removal of the tumor impossible and neither radiation nor current chemotherapy provide cure. Recent evidence shows that glioblastoma multiforme consists of heterogeneous cell populations which differ in tumor-forming potential. Enriched tumor-initiating capacity has been linked to poorly differentiated glioblastoma cells sharing features with neural stem cells. Thus, these cells are important targets for new therapeutic strategies. We aim to identify novel targets controlling maintenance and differentiation in glioblastoma-initiating cells through high throughput screening. To this end, we utilized libraries of small chemical compounds and small interference RNAs in combination with automated imaging and data analysis. Patient-derived glioblastoma cells were expanded and characterized using neural stem cell conditions. In culture, the cells showed low differentiation but expression of neural stem cell markers such as Nestin and Sox2. Upon intracranial injection into SCID mice these cells gave rise to tumors displaying the hallmarks of the human disease. Differentiation of glioblastoma-initiating cells (for example elicited through bone morphogenetic protein, BMP) was associated with strong morphological changes. Hence, cellular morphology, as well as markers specific for differentiation or death were used as screen readout. Lentiviral RNA interference-based screening yielded several gene knockdowns leading to ‘forced’ differentiation of glioblastoma-initiating cells. For example, knockdown of TRRAP (transformation/transcription domain associated protein) led to strongly increased differentiation and loss of proliferative and self-renewing capacity in these cells. TRRAP is an adapter protein implicated in oncogenic transformation through c-MYC transcription activation, also participating in chromatin remodeling and DNA repair. Glioblastoma-initiating cells with reduced TRRAP displayed increased apoptosis upon treatment with the genotoxic agent temozolomide. In vivo, Trapp knockdown cells were not able to give rise to glioblastoma upon transplantation into the brain of SCID mice. Together, these findings support a crucial role for TRRAP in maintenance and tumorigenicity of glioblastoma-initiating cells and might offer future therapeutic options.
Project description:Brain tumor neurospheres (BTCSs) are cancer cells with neural stem cell-like properties found in the fatal brain tumor glioblastoma multiforme (GBM). These cells account for less than 1% of total tumor cells, are poorly differentiated and are believed to be involved in tumor induction, progression, treatment resistance and relapse. Specific miRNAs play important roles in modulating the proliferation and differentiation of neural stem cells, therefore, we aimed to identify miRNAs controlling differentiation in GBM-BTSCs through high throughput screening miRNA array profiling. We compared the miRNA expression profiles at the neurosphere state and upon 4 and 14days of differentiation by using LIMMA, finding 21 differentially expressed miRNAs : hsa-miR-103, hsa-miR-106a, hsa-miR-106b, hsa-miR-15b, hsa-miR-17, hsa-miR-19a, hsa-miR-20a, hsa-miR-25, hsa-miR-301a and hsa-miR-93 were found up-regulated upon differentiation, while hsa-miR-100, hsa-miR-1259, hsa-miR-21, hsa-miR-22, hsa-miR-221, hsa-miR-222, hsa-miR-23b, hsa-miR-27a, hsa-miR-27b, hsa-miR-29a and hsa-miR-29b were down-regulated. Expression of 11 of the 21 miRNAs was examined by qPCR and 7 of them were validated: hsa-miR-21, hsa-miR-29a, hsa-miR-29b, hsa-miR-221 and hsa-miR-222 increased their expression upon differentiation, while hsa-miR-93 and hsa-miR-106a were inhibited. Functional studies demonstrated that miR-21 over-expression induced the expression of glial and/or neuronal cell markers in the neurospheres, possibly due to SPRY1 targeting by miR-21 in these cells, while miR-221 and miR-222 inhibition at the differentiated state reduced the expression of those differentiation markers. On the other hand, miR-29a and miR-29b targeted MCL1 in the GBM neurospheres and increased apoptotic cell death. Gene expression in differentiated cells relative to neurospheres in four different glioblastoma cultures
Project description:Glioblastoma multiforme is one of the most devastating cancers and presents unique challenges to therapy due to its aggressive behaviour. Cancer stem cells have been described to be the only cell population with tumorogenic capacity in glioblastoma. Therefore, effective therapeutic strategies targeting these cells may be beneficial. We have established different cultures of glioblastoma stem cells (GSCs) derived from surgical specimens and found that, after induction of differentiation, NFκB was activated, which allows intermediate tumor precursor cells to remain cycling. We also showed that blockade of NFκB signaling in differentiating GSCs by different genetic strategies or treatment with small molecule inhibitors, promoted replication arrest, progression to a mature phenotype, mainly neuronal cells, and senescence. This effect was partly mediated by downregulation of the NFκB target gene cyclin D1. Furthermore, intravenous treatment of immunodeficient mice bearing human GSC-derived tumors with a novel small-molecule inhibitor of the NFκB pathway induced senescence of tumor cells but no ultraestructural alterations of the brain parenchymal cells were detected. These findings reveal that activation of NFκB may keep differentiating GSCs from acquiring a mature postmitotic phenotype, thus allowing cell proliferation, and support the rationale for therapeutic strategies aimed at promoting premature senescence in GSCs undergoing differentiation. Gene expression in differentiated cells relative to stem cells in three different glioblastoma cultures
Project description:MicroRNAs are short non-coding RNA molecules playing regulatory roles in animals and plants by repressing translation or cleaving RNA transcripts. The specific modulation of several microRNAs has been recently associated to some forms of human cancer, suggesting that these short molecules can represent a new class of genes involved in oncogenesis. In our study, we examined by microarray the global expression levels of 245 microRNAs in glioblastoma multiforme (GBM), the most frequent and malignant of primary brain tumors. The analysis of both glioblastoma tissues and glioblastoma cell lines allowed us to identify a group of microRNAs whose expression is significantly altered in this tumor. The most interesting results came from miR-221, strongly upregulated in glioblastoma and a set of brain-enriched miRNAs, miR-128, miR-181a, miR-181b, miR-181c, which are down-regulated in glioblastoma.
Project description:Brain tumor neurospheres (BTCSs) are cancer cells with neural stem cell-like properties found in the fatal brain tumor glioblastoma multiforme (GBM). These cells account for less than 1% of total tumor cells, are poorly differentiated and are believed to be involved in tumor induction, progression, treatment resistance and relapse. Specific miRNAs play important roles in modulating the proliferation and differentiation of neural stem cells, therefore, we aimed to identify miRNAs controlling differentiation in GBM-BTSCs through high throughput screening miRNA array profiling. We compared the miRNA expression profiles at the neurosphere state and upon 4 and 14 days of differentiation by using LIMMA, finding 21 differentially expressed miRNAs : hsa-miR-103, hsa-miR-106a, hsa-miR-106b, hsa-miR-15b, hsa-miR-17, hsa-miR-19a, hsa-miR-20a, hsa-miR-25, hsa-miR-301a and hsa-miR-93 were found up-regulated upon differentiation, while hsa-miR-100, hsa-miR-1259, hsa-miR-21, hsa-miR-22, hsa-miR-221, hsa-miR-222, hsa-miR-23b, hsa-miR-27a, hsa-miR-27b, hsa-miR-29a and hsa-miR-29b were down-regulated. Expression of 11 of the 21 miRNAs was examined by qPCR and 7 of them were validated: hsa-miR-21, hsa-miR-29a, hsa-miR-29b, hsa-miR-221 and hsa-miR-222 increased their expression upon differentiation, while hsa-miR-93 and hsa-miR-106a were inhibited. Functional studies demonstrated that miR-21 over-expression induced the expression of glial and/or neuronal cell markers in the neurospheres, possibly due to SPRY1 targeting by miR-21 in these cells, while miR-221 and miR-222 inhibition at the differentiated state reduced the expression of those differentiation markers. On the other hand, miR-29a and miR-29b targeted MCL1 in the GBM neurospheres and increased apoptotic cell death. Five GBM cell lines at the neurosphere state or after 4 or 14 days of differentiation
Project description:Glioblastoma multiforme (GBM), a grade IV astrocytoma, is the most common and aggressive brain tumor in adults, characterized by being highly infiltrative, angiogenic, and resistant to chemotherapy and radiotherapy. In previous works, has been determined that progesterone P4 increases proliferation, migration and invasion of cells derived from human GBMs through the interaction with its intracellular receptor (PR). In breast cancer, there exist evidence that P4 regulates the expression of miRNAs with tumor suppressor or oncogenic action, via the classical PR. The signature of miRNAs affected by P4 treatment in cells derived from human GBMs has not been determined. Therefore, we studied the effect of P4 on miRNAs expression pattern in U251 cells derived from a human GBM.
Project description:Brain tumor neurospheres (BTCSs) are cancer cells with neural stem cell-like properties found in the fatal brain tumor glioblastoma multiforme (GBM). These cells account for less than 1% of total tumor cells, are poorly differentiated and are believed to be involved in tumor induction, progression, treatment resistance and relapse. Specific miRNAs play important roles in modulating the proliferation and differentiation of neural stem cells, therefore, we aimed to identify miRNAs controlling differentiation in GBM-BTSCs through high throughput screening miRNA array profiling. We compared the miRNA expression profiles at the neurosphere state and upon 4 and 14 days of differentiation by using LIMMA, finding 21 differentially expressed miRNAs : hsa-miR-103, hsa-miR-106a, hsa-miR-106b, hsa-miR-15b, hsa-miR-17, hsa-miR-19a, hsa-miR-20a, hsa-miR-25, hsa-miR-301a and hsa-miR-93 were found up-regulated upon differentiation, while hsa-miR-100, hsa-miR-1259, hsa-miR-21, hsa-miR-22, hsa-miR-221, hsa-miR-222, hsa-miR-23b, hsa-miR-27a, hsa-miR-27b, hsa-miR-29a and hsa-miR-29b were down-regulated. Expression of 11 of the 21 miRNAs was examined by qPCR and 7 of them were validated: hsa-miR-21, hsa-miR-29a, hsa-miR-29b, hsa-miR-221 and hsa-miR-222 increased their expression upon differentiation, while hsa-miR-93 and hsa-miR-106a were inhibited. Functional studies demonstrated that miR-21 over-expression induced the expression of glial and/or neuronal cell markers in the neurospheres, possibly due to SPRY1 targeting by miR-21 in these cells, while miR-221 and miR-222 inhibition at the differentiated state reduced the expression of those differentiation markers. On the other hand, miR-29a and miR-29b targeted MCL1 in the GBM neurospheres and increased apoptotic cell death.