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Borovski T, Vellinga TT, Laoukili J, Santo EE, Fatrai S, van Schelven S, Verheem A, Marvin DL, Ubink I, Borel Rinkes IHM, Kranenburg O. Inhibition of RAF1 kinase activity restores apicobasal polarity and impairs tumour growth in human colorectal cancer. Gut 2017; 66:1106-1115. [PMID: 27670374 DOI: 10.1136/gutjnl-2016-311547] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2016] [Accepted: 08/30/2016] [Indexed: 12/08/2022]
Abstract
BACKGROUND AND AIM Colorectal cancer (CRC) remains one of the leading causes of cancer-related death. Novel therapeutics are urgently needed, especially for tumours with activating mutations in KRAS (∼40%). Here we investigated the role of RAF1 in CRC, as a potential, novel target. METHODS Colonosphere cultures were established from human tumour specimens obtained from patients who underwent colon or liver resection for primary or metastatic adenocarcinoma. The role of RAF1 was tested by generating knockdowns (KDs) using three independent shRNA constructs or by using RAF1-kinase inhibitor GW5074. Clone-initiating and tumour-initiating capacities were assessed by single-cell cloning and injecting CRC cells into immune-deficient mice. Expression of tight junction (TJ) proteins, localisation of polarity proteins and activation of MEK-ERK pathway was analysed by western blot, immunohistochemistry and immunofluorescence. RESULTS KD or pharmacological inhibition of RAF1 significantly decreased clone-forming and tumour-forming capacity of all CRC cultures tested, including KRAS-mutants. This was not due to cytotoxicity but, at least in part, to differentiation of tumour cells into goblet-like cells. Inhibition of RAF1-kinase activity restored apicobasal polarity and the formation of TJs in vitro and in vivo, without reducing MEK-ERK phosphorylation. MEK-inhibition failed to restore polarity and TJs. Moreover, RAF1-impaired tumours were characterised by normalised tissue architecture. CONCLUSIONS RAF1 plays a critical role in maintaining the transformed phenotype of CRC cells, including those with mutated KRAS. The effects of RAF1 are kinase-dependent, but MEK-independent. Despite the lack of activating mutations in RAF1, its kinase domain is an attractive therapeutic target for CRC.
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Affiliation(s)
- Tijana Borovski
- Cancer Center, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Thomas T Vellinga
- Cancer Center, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Jamila Laoukili
- Cancer Center, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Evan E Santo
- Department of Pathology and Laboratory Medicine, Weill Cornell Medical College, New York City, New York, USA
| | - Szabolcs Fatrai
- Department of Hematology, Erasmus Medical Center, Rotterdam, The Netherlands
| | | | - Andre Verheem
- Cancer Center, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Dieuwke L Marvin
- Cancer Center, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Inge Ubink
- Cancer Center, University Medical Center Utrecht, Utrecht, The Netherlands
| | | | - Onno Kranenburg
- Cancer Center, University Medical Center Utrecht, Utrecht, The Netherlands
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Fessler E, Borovski T, Medema JP. Endothelial cells induce cancer stem cell features in differentiated glioblastoma cells via bFGF. Mol Cancer 2015; 14:157. [PMID: 26282129 PMCID: PMC4539660 DOI: 10.1186/s12943-015-0420-3] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2015] [Accepted: 07/23/2015] [Indexed: 12/19/2022] Open
Abstract
Background Glioblastoma multiforme (GBM) is a rapidly growing malignant brain tumor, which has been reported to be organized in a hierarchical fashion with cancer stem cells (CSCs) at the apex. Recent studies demonstrate that this hierarchy does not follow a one-way route but can be reverted with more differentiated cells giving rise to cells possessing CSC features. We investigated the role of tumor microvascular endothelial cells (tMVECs) in reverting differentiated glioblastoma cells to CSC-like cells. Methods We made use of primary GBM lines and tMVECs. To ensure differentiation, CSC-enriched cultures were forced into differentiation using several stimuli and cultures consisting solely of differentiated cells were obtained by sorting on the oligodendrocyte marker O4. Reversion to the CSC state was assessed phenotypically by CSC marker expression and functionally by evaluating clonogenic and multilineage differentiation potential. Results Conditioned medium of tMVECs was able to replenish the CSC pool by phenotypically and functionally reverting differentiated GBM cells to the CSC state. Basic fibroblast growth factor (bFGF), secreted by tMVECs, recapitulated the effects of the conditioned medium in inducing re-expression of CSC markers and increasing neurosphere formation ability of differentiated GBM cells. Conclusions Our findings demonstrate that the CSC-based hierarchy displays a high level of plasticity showing that differentiated GBM cells can acquire CSC features when placed in the right environment. These results point to the need to intersect the elaborate network of tMVECs and GBM CSCs for efficient elimination of GBM CSCs. Electronic supplementary material The online version of this article (doi:10.1186/s12943-015-0420-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Evelyn Fessler
- Laboratory for Experimental Oncology and Radiobiology (LEXOR), Center for Experimental Molecular Medicine (CEMM), Academic Medical Center (AMC), University of Amsterdam, Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands.
| | - Tijana Borovski
- Laboratory for Experimental Oncology and Radiobiology (LEXOR), Center for Experimental Molecular Medicine (CEMM), Academic Medical Center (AMC), University of Amsterdam, Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands. .,Present address: Department of Surgery, University Medical Center (UMC) Utrecht, Utrecht, The Netherlands.
| | - Jan Paul Medema
- Laboratory for Experimental Oncology and Radiobiology (LEXOR), Center for Experimental Molecular Medicine (CEMM), Academic Medical Center (AMC), University of Amsterdam, Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands.
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Vellinga TT, Borovski T, de Boer VCJ, Fatrai S, van Schelven S, Trumpi K, Verheem A, Snoeren N, Emmink BL, Koster J, Rinkes IHMB, Kranenburg O. SIRT1/PGC1α-Dependent Increase in Oxidative Phosphorylation Supports Chemotherapy Resistance of Colon Cancer. Clin Cancer Res 2015; 21:2870-9. [PMID: 25779952 DOI: 10.1158/1078-0432.ccr-14-2290] [Citation(s) in RCA: 132] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2014] [Accepted: 02/27/2015] [Indexed: 11/16/2022]
Abstract
PURPOSE Chemotherapy treatment of metastatic colon cancer ultimately fails due to development of drug resistance. Identification of chemotherapy-induced changes in tumor biology may provide insight into drug resistance mechanisms. EXPERIMENTAL DESIGN We studied gene expression differences between groups of liver metastases that were exposed to preoperative chemotherapy or not. Multiple patient-derived colonosphere cultures were used to assess how chemotherapy alters energy metabolism by measuring mitochondrial biomass, oxygen consumption, and lactate production. Genetically manipulated colonosphere-initiated tumors were used to assess how altered energy metabolism affects chemotherapy efficacy. RESULTS Gene ontology and pathway enrichment analysis revealed significant upregulation of genes involved in oxidative phosphorylation (OXPHOS) and mitochondrial biogenesis in metastases that were exposed to chemotherapy. This suggested chemotherapy induces a shift in tumor metabolism from glycolysis towards OXPHOS. Indeed, chemotreatment of patient-derived colonosphere cultures resulted in an increase of mitochondrial biomass, increased expression of respiratory chain enzymes, and higher rates of oxygen consumption. This was mediated by the histone deacetylase sirtuin-1 (SIRT1) and its substrate, the transcriptional coactivator PGC1α. Knockdown of SIRT1 or PGC1α prevented chemotherapy-induced OXPHOS and significantly sensitized patient-derived colonospheres as well as tumor xenografts to chemotherapy. CONCLUSIONS Chemotherapy of colorectal tumors induces a SIRT1/PGC1α-dependent increase in OXPHOS that promotes tumor survival during treatment. This phenomenon is also observed in chemotherapy-exposed resected liver metastases, strongly suggesting that chemotherapy induces long-lasting changes in tumor metabolism that potentially interfere with drug efficacy. In conclusion, we propose a novel mechanism of chemotherapy resistance that may be clinically relevant and therapeutically exploitable.
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Affiliation(s)
- Thomas T Vellinga
- Department of Surgery, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Tijana Borovski
- Department of Surgery, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Vincent C J de Boer
- Department of Clinical Chemistry, Laboratory Genetic Metabolic Diseases, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
| | - Szabolcs Fatrai
- Department of Surgery, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Susanne van Schelven
- Department of Surgery, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Kari Trumpi
- Department of Surgery, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Andre Verheem
- Department of Surgery, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Nikol Snoeren
- Department of Surgery, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Benjamin L Emmink
- Department of Surgery, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Jan Koster
- Department of Oncogenomics, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
| | | | - Onno Kranenburg
- Department of Surgery, University Medical Center Utrecht, Utrecht, the Netherlands.
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Vellinga TT, Boer VCD, Borovski T, Trumpi K, Fatrai S, Kranenburg O, Rinkes IHB, Hagendoorn J. Abstract 3351: Survival of colorectal cancer cells following chemotherapy relies on a SIRT1-dependent increase in oxidative phosphorylation. Cancer Res 2014. [DOI: 10.1158/1538-7445.am2014-3351] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Background: Altered energy metabolism is one of the hallmarks of cancer. Tumor cells reprogram their energy metabolism to meet the demands of uncontrolled cell division. During tumorigenesis the vast majority of cancer cells become highly glycolytic (Warburg effect) accompanied by a decrease in oxidative metabolism. Chemotherapy is likely to affect the energy metabolism of tumor cells, but how specific drugs affect specific metabolic pathways is only beginning to be addressed.
Methods: the effects of cytotoxic agents on energy metabolism were assessed by flow cytometric uptake of Mitotracker®, the ratio of mitochondrial and nuclear DNA on qRT-PCR, western blotting for protein levels of the different complexes of the respiratory chain and oxygen consumption rate by the Seahorse Extracellular Flux Analyzer. Cell death was analyzed by flow cytometric uptake of Propidium Iodide, Nicoletti assay and protein levels of caspases 3 and 8.
Results: Gene expression analysis was performed on 119 resected liver metastases of colorectal tumors. Of all clinical variables tested, neoadjuvant chemotherapy was most prominently associated with changes in gene expression. Gene ontology and pathway analysis tools revealed that many of the chemotherapy-associated genes were involved in the regulation of oxidative phosphorylation (OxPhos). To test whether chemotherapy affects OxPhos patient derived colorectal spheroids were treated with the standard cytotoxic agents oxaliplatin and 5-fluorouracil. Chemotherapy strongly increases mitochondrial load, oxygen consumption rate and mitochondrial ATP synthesis.
In line with these results chemo-treated tumor cells displayed a higher ratio of mitochondrial-to-nuclear DNA and expression of respiratory complex components was strongly increased following chemotherapy. Chemotherapy strongly induced expression of the histone deacetylase SIRT1, which has been implicated in mitochondrial biogenesis. Inhibition (by either nicotinamide, EX-527, Tenovin-6) or knockdown of SIRT1 prevented the chemotherapy-induced increase in oxidative phosphorylation. Moreover, SIRT1 knockdown greatly reduced tumor cell survival and clonogenic capacity following removal of chemotherapy.
Conclusion: Chemotherapy induces an increase in oxidative phosphorylation via SIRT1 and this is required for tumor cell survival following drug removal. Since DNA repair requires ATP, mitochondrial biogenesis may be part of the tumor cell response to DNA-damaging agents. Post-chemotherapy targeting of SIRT1 (or OxPhos enzymes) may be an interesting novel approach to increase chemotherapy efficacy.
Citation Format: Thomas T. Vellinga, Vincent C. de Boer, Tijana Borovski, Kari Trumpi, Szabolcs Fatrai, Onno Kranenburg, Inne H.M. Borel Rinkes, Jeroen Hagendoorn. Survival of colorectal cancer cells following chemotherapy relies on a SIRT1-dependent increase in oxidative phosphorylation. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 3351. doi:10.1158/1538-7445.AM2014-3351
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Affiliation(s)
| | | | | | - Kari Trumpi
- 1University Medical Centre Utrecht, Utrecht, Netherlands
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Bergs JWJ, Krawczyk PM, Borovski T, ten Cate R, Rodermond HM, Stap J, Medema JP, Haveman J, Essers J, van Bree C, Stalpers LJA, Kanaar R, Aten JA, Franken NAP. Inhibition of homologous recombination by hyperthermia shunts early double strand break repair to non-homologous end-joining. DNA Repair (Amst) 2012; 12:38-45. [PMID: 23237939 DOI: 10.1016/j.dnarep.2012.10.008] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2011] [Revised: 10/11/2012] [Accepted: 10/12/2012] [Indexed: 02/02/2023]
Abstract
In S and G2 phase mammalian cells DNA double strand breaks (DSBs) can potentially be repaired by homologous recombination (HR) or non-homologous end-joining (NHEJ). Results of several studies suggest that these two mechanistically distinct repair pathways can compete for DNA ends. Because HR and NHEJ differ with respect to error susceptibility, generation of chromosome rearrangements, which are potentially carcinogenic products of DSB repair, may depend on the pathway choice. To investigate this hypothesis, the influence of HR and NHEJ inhibition on the frequencies of chromosome aberrations in G2 phase cells was investigated. SW-1573 and RKO cells were treated with mild (41 °C) hyperthermia in order to disable HR and/or NU7441/cisplatin to inactivate NHEJ and frequencies of chromosomal fragments (resulting from unrepaired DSBs) and translocations (products of erroneous DSB rejoining) were studied using premature chromosome condensation (PCC) combined with fluorescence in situ hybridization (FISH). It is shown here that temporary inhibition of HR by hyperthermia results in increased frequency of ionizing-radiation (IR)-induced chromosomal translocations and that this effect is abrogated by NU7441- or cisplatin-mediated inhibition of NHEJ. The results suggest that in the absence of HR, DSB repair is shifted to the error-prone NHEJ pathway resulting in increased frequencies of chromosomal rearrangements. These results might be of consequence for clinical cancer treatment approaches that aim at inhibition of one or more DSB repair pathways.
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Affiliation(s)
- Judith W J Bergs
- Laboratory for Experimental Oncology and Radiobiology (LEXOR), Center for Experimental Molecular Medicine, Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, P.O. Box 22700, 1100 DE Amsterdam, The Netherlands
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Krawczyk PM, Borovski T, Stap J, Cijsouw T, ten Cate R, Medema JP, Kanaar R, Franken NAP, Aten JA. Chromatin mobility is increased at sites of DNA double-strand breaks. J Cell Sci 2012; 125:2127-33. [PMID: 22328517 DOI: 10.1242/jcs.089847] [Citation(s) in RCA: 109] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
DNA double-strand breaks (DSBs) can efficiently kill cancer cells, but they can also produce unwanted chromosome rearrangements when DNA ends from different DSBs are erroneously joined. Movement of DSB-containing chromatin domains might facilitate these DSB interactions and promote the formation of chromosome rearrangements. Therefore, we analyzed the mobility of chromatin domains containing DSBs, marked by the fluorescently tagged DSB marker 53BP1, in living mammalian cells and compared it with the mobility of undamaged chromatin on a time-scale relevant for DSB repair. We found that chromatin domains containing DSBs are substantially more mobile than intact chromatin, and are capable of roaming a more than twofold larger area of the cell nucleus. Moreover, this increased DSB mobility, but not the mobility of undamaged chromatin, can be reduced by agents that affect higher-order chromatin organization.
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Affiliation(s)
- P M Krawczyk
- van Leeuwenhoek Centre for Advanced Microscopy-AMC, Department of Cell Biology & Histology, University of Amsterdam, Amsterdam, The Netherlands.
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Abstract
Tumors are being increasingly perceived as abnormal organs that, in many respects, recapitulate the outgrowth and differentiation patterns of normal tissues. In line with this idea is the observation that only a small fraction of tumor cells is capable of initiating a new tumor. Because of the features that these cells share with somatic stem cells, they have been termed cancer stem cells (CSC). Normal stem cells reside in a "stem cell niche" that maintains them in a stem-like state. Recent data suggest that CSCs also rely on a similar niche, dubbed the "CSC niche," which controls their self-renewal and differentiation. Moreover, CSCs can be generated by the microenvironment through induction of CSC features in more differentiated tumor cells. In addition to a role in CSC maintenance, the microenvironment is hypothesized to be involved in metastasis by induction of the epithelial-mesenchymal transition, leading to dissemination and invasion of tumor cells. The localization of secondary tumors also seems to be orchestrated by the microenvironment, which is suggested to form a premetastatic niche. Thus, the microenvironment seems to be of crucial importance for primary tumor growth as well as metastasis formation. Combined with its role in the protection of CSCs against genotoxic insults, these data strongly put forward the niche as an important target for novel therapies.
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Affiliation(s)
- Tijana Borovski
- Laboratory for Experimental Oncology and Radiobiology, Center for Experimental Molecular Medicine, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
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Vermeulen L, De Sousa E Melo F, van der Heijden M, Cameron K, de Jong JH, Borovski T, Tuynman JB, Todaro M, Merz C, Rodermond H, Sprick MR, Kemper K, Richel DJ, Stassi G, Medema JP. Wnt activity defines colon cancer stem cells and is regulated by the microenvironment. Nat Cell Biol 2010; 12:468-76. [DOI: 10.1038/ncb2048] [Citation(s) in RCA: 1412] [Impact Index Per Article: 100.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2010] [Accepted: 03/26/2010] [Indexed: 11/09/2022]
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Sottoriva A, Verhoeff JJC, Borovski T, McWeeney SK, Naumov L, Medema JP, Sloot PMA, Vermeulen L. Cancer stem cell tumor model reveals invasive morphology and increased phenotypical heterogeneity. Cancer Res 2010; 70:46-56. [PMID: 20048071 DOI: 10.1158/0008-5472.can-09-3663] [Citation(s) in RCA: 140] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The recently developed concept of cancer stem cells (CSC) sheds new light on various aspects of tumor growth and progression. Here, we present a mathematical model of malignancies to investigate how a hierarchical organized cancer cell population affects the fundamental properties of solid malignancies. We establish that tumors modeled in a CSC context more faithfully resemble human malignancies and show invasive behavior, whereas tumors without a CSC hierarchy do not. These findings are corroborated by in vitro studies. In addition, we provide evidence that the CSC model is accompanied by highly altered evolutionary dynamics compared with the ones predicted to exist in a stochastic, nonhierarchical tumor model. Our main findings indicate that the CSC model allows for significantly higher tumor heterogeneity, which may affect therapy resistance. Moreover, we show that therapy which fails to target the CSC population is not only unsuccessful in curing the patient, but also promotes malignant features in the recurring tumor. These include rapid expansion, increased invasion, and enhanced heterogeneity.
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Affiliation(s)
- Andrea Sottoriva
- Computational Science, Faculty of Science, University of Amsterdam, Amsterdam, the Netherlands
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Borovski T, Verhoeff JJC, ten Cate R, Cameron K, de Vries NA, van Tellingen O, Richel DJ, van Furth WR, Medema JP, Sprick MR. Tumor microvasculature supports proliferation and expansion of glioma-propagating cells. Int J Cancer 2009; 125:1222-30. [PMID: 19431144 DOI: 10.1002/ijc.24408] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Glioblastoma multiforme (GBM) is the most common and aggressive primary brain tumor. The identification of 'cancer stem cells' (CSC) has shed new light on the potential mechanism of therapy resistance of these tumors. Because these cells appear to be more resistant to conventional treatments, they are thought to drive tumor regrowth after therapy. Therefore, novel therapeutic approaches that target these cells are needed. Tumor cells interact with their microenvironment. It has been reported that close contact between CSCs and tumor microvascular endothelium in GBM is important for CSCs to preserve their undifferentiated state and self-renewal ability. However, our understanding of this interaction is still rudimentary. This is in part due to a lack of suitable in vitro models that accurately represent the in vivo situation. Therefore, we set up a co-culture system consisting of primary brain tumor microvascular endothelial cells (tMVECs) and glioma propagating cells (GPCs) derived from biopsies of GBM patients. We found that tMVECs support the growth of GPCs resulting in higher proliferation rates comparing to GPCs cultured alone. This effect was dependent on direct contact between the 2 cell types. In contrast to GPCs, the FCS-cultured cell line U87 was stimulated by culturing on tMVEC-derived ECM alone, suggesting that both cell types interact different with their microenvironment. Together, these results demonstrate the feasibility and utility of our system to model the interaction of GPCs with their microenvironment. Identification of molecules that mediate this interaction could provide novel targets for directed therapy for GBM.
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Abstract
The CSC compartment represents the subpopulation of tumor cells with clonogenic potential and the ability to initiate new tumors. Besides self renewal, one of their main features is their ability to differentiate into the variety of cells within the tumor. The question remains whether this potential resides within the single CSC or whether many different CSCs are necessary to generate a heterogeneous population of tumor cells. There is an increasing amount of evidence showing that a single CSC indeed has the potential to reconstitute the complete tumor phenotype. This is likely to be a general phenomenon and it has been demonstrated in many tumors so far. Here we show that single GBM CSCs have multilineage potential, although not exclusively. Furthermore, our results show that CSCs originating from same tumor are not necessarily uniform in respect to their differentiation potential.
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Affiliation(s)
- Tijana Borovski
- Laboratory for Experimental Oncology and Radiobiology, LEXOR, CEMM, AMC UvA, Amsterdam, The Netherlands
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