1
|
Subbarayan R, Murugan Girija D, Raja STK, Krishnamoorthy A, Srinivasan D, Shrestha R, Srivastava N, Ranga Rao S. Conditioned medium-enriched umbilical cord mesenchymal stem cells: a potential therapeutic strategy for spinal cord injury, unveiling transcriptomic and secretomic insights. Mol Biol Rep 2024; 51:570. [PMID: 38658405 DOI: 10.1007/s11033-024-09503-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2024] [Accepted: 04/02/2024] [Indexed: 04/26/2024]
Abstract
INTRODUCTION Spinal cord injury (SCI) leads to significant destruction of nerve tissue, causing the degeneration of axons and the formation of cystic cavities. This study aimed to examine the characteristics of human umbilical cord-derived mesenchymal stem cells (HUCMSCs) cultured in a serum-free conditioned medium (CM) and assess their effectiveness in a well-established hemitransection SCI model. MATERIALS AND METHODS In this study, HUCMSCs cultured medium was collected and characterized by measuring IL-10 and identifying proteomics using mass spectroscopy. This collected serum-free CM was further used in the experiments to culture and characterize the HUMSCs. Later, neuronal cells derived from CM-enriched HUCMSC were tested sequentially using an injectable caffeic acid-bioconjugated gelatin (CBG), which was further transplanted in a hemitransection SCI model. In vitro, characterization of CM-enriched HUCMSCs and differentiated neuronal cells was performed using flow cytometry, immunofluorescence, electron microscopy, and post-transplant analysis using immunohistology analysis, qPCR, in vivo bioluminescence imaging, and behavioral analysis using an infrared actimeter. RESULTS The cells that were cultured in the conditioned media produced a pro-inflammatory cytokine called IL-10. Upon examining the secretome of the conditioned media, the Kruppel-like family of KRAB and zinc-finger proteins (C2H2 and C4) were found to be activated. Transcriptome analysis also revealed an increased expression of ELK-1, HOXD8, OTX2, YY1, STAT1, ETV7, and PATZ1 in the conditioned media. Furthermore, the expression of Human Stem-101 confirmed proliferation during the first 3 weeks after transplantation, along with the migration of CBG-UCNSC cells within the transplanted area. The gene analysis showed increased expression of Nestin, NeuN, Calb-2, Msi1, and Msi2. The group that received CBG-UCNSC therapy showed a smooth recovery by the end of week 2, with most rats regaining their walking abilities similar to those before the spinal cord injury by week 5. CONCLUSIONS In conclusion, the CBG-UCNSC method effectively preserved the integrity of the transplanted neuronal-like cells and improved locomotor function. Thus, CM-enriched cells can potentially reduce biosafety risks associated with animal content, making them a promising option for clinical applications in treating spinal cord injuries.
Collapse
Affiliation(s)
- Rajasekaran Subbarayan
- Centre for Advanced Biotherapeutics and Regenerative Medicine, Research-FAHS, Chettinad Hospital and Research Institute, Chettinad Academy of Research and Education, Kelambakkam, 603013, India.
| | | | | | | | - Dhasarathdev Srinivasan
- Centre for Advanced Biotherapeutics and Regenerative Medicine, Research-FAHS, Chettinad Hospital and Research Institute, Chettinad Academy of Research and Education, Kelambakkam, 603013, India
| | | | | | - Suresh Ranga Rao
- Department of Engineering Design, Indian Institute of Technology Madras, Chennai, India
| |
Collapse
|
2
|
Kamte YS, Chandwani MN, London NM, Potosnak CE, Leak RK, O'Donnell LA. Perturbations in neural stem cell function during a neurotropic viral infection in juvenile mice. J Neurochem 2023; 166:809-829. [PMID: 37530081 DOI: 10.1111/jnc.15914] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Revised: 06/25/2023] [Accepted: 06/28/2023] [Indexed: 08/03/2023]
Abstract
Viral infections of the central nervous system (CNS) often cause worse neurological outcomes in younger hosts. Throughout childhood, the brain undergoes extensive development and refinement to produce functional neural networks. Network function is maintained partly with the help of neural stem cells (NSCs) that replace neuronal and glia subtypes in the two neurogenic niches of the brain (the hippocampus and subventricular zone). Accumulating evidence suggests that viruses disrupt NSC function in adulthood and infancy, but the in vivo impact of childhood infections on acute and long-term NSC function is unknown. Using a juvenile mouse model of measles virus (MeV) infection, where only mature neurons in the brain are infected, we defined the effects of the antiviral immune response on NSCs from juvenile to adult stages of life. We found that (a) virus persists in the brains of survivors despite an anti-viral immune response; (b) NSC numbers decrease dramatically during early infection, but ultimately stabilize in adult survivors; (c) infection is associated with mild apoptosis throughout the juvenile brain, but NSC proliferation is unchanged; (d) the loss of NSC numbers is dependent upon the stage of NSC differentiation; and (e) immature neurons increase early during infection, concurrent with depletion of NSC pools. Collectively, we show that NSCs are exquisitely sensitive to the inflammatory microenvironment created during neuron-restricted MeV infection in juveniles, responding with an early loss of NSCs but increased neurogenesis. These studies provide insight into potential cellular mechanisms associated with long-term neurological deficits in survivors of childhood CNS infections.
Collapse
Affiliation(s)
- Yashika S Kamte
- School of Pharmacy and the Graduate School of Pharmaceutical Sciences, Duquesne University, Pittsburgh, Pennsylvania, USA
| | - Manisha N Chandwani
- School of Pharmacy and the Graduate School of Pharmaceutical Sciences, Duquesne University, Pittsburgh, Pennsylvania, USA
| | - Natalie M London
- School of Pharmacy and the Graduate School of Pharmaceutical Sciences, Duquesne University, Pittsburgh, Pennsylvania, USA
| | - Chloe E Potosnak
- School of Pharmacy and the Graduate School of Pharmaceutical Sciences, Duquesne University, Pittsburgh, Pennsylvania, USA
| | - Rehana K Leak
- School of Pharmacy and the Graduate School of Pharmaceutical Sciences, Duquesne University, Pittsburgh, Pennsylvania, USA
| | - Lauren A O'Donnell
- School of Pharmacy and the Graduate School of Pharmaceutical Sciences, Duquesne University, Pittsburgh, Pennsylvania, USA
| |
Collapse
|
3
|
Bertoldo JB, Müller S, Hüttelmaier S. RNA-binding proteins in cancer drug discovery. Drug Discov Today 2023; 28:103580. [PMID: 37031812 DOI: 10.1016/j.drudis.2023.103580] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Revised: 03/25/2023] [Accepted: 03/29/2023] [Indexed: 04/11/2023]
Abstract
RNA-binding proteins (RBPs) are crucial players in tumorigenesis and, hence, promising targets in cancer drug discovery. However, they are largely regarded as 'undruggable', because of the often noncatalytic and complex interactions between protein and RNA, which limit the discovery of specific inhibitors. Nonetheless, over the past 10 years, drug discovery efforts have uncovered RBP inhibitors with clinical relevance, highlighting the disruption of RNA-protein networks as a promising avenue for cancer therapeutics. In this review, we discuss the role of structurally distinct RBPs in cancer, and the mechanisms of RBP-directed small-molecule inhibitors (SMOIs) focusing on drug-protein interactions, binding surfaces, potency, and translational potential. Additionally, we underline the limitations of RBP-targeting drug discovery assays and comment on future trends in the field.
Collapse
Affiliation(s)
- Jean B Bertoldo
- Children's Cancer Institute, Lowy Cancer Research Centre, UNSW Sydney, Sydney, NSW, Australia; School of Clinical Medicine, UNSW Sydney, Sydney, NSW, Australia
| | - Simon Müller
- Institute for Molecular Medicine, Faculty of Medicine, Martin-Luther University of Halle-Wittenberg, Halle (Saale), Germany; New York Genome Center, New York, NY, USA; Department of Biology, New York University, New York, NY, USA
| | - Stefan Hüttelmaier
- Institute for Molecular Medicine, Faculty of Medicine, Martin-Luther University of Halle-Wittenberg, Halle (Saale), Germany.
| |
Collapse
|
4
|
Polat B, Wohlleben G, Kosmala R, Lisowski D, Mantel F, Lewitzki V, Löhr M, Blum R, Herud P, Flentje M, Monoranu CM. Differences in stem cell marker and osteopontin expression in primary and recurrent glioblastoma. Cancer Cell Int 2022; 22:87. [PMID: 35183162 PMCID: PMC8858483 DOI: 10.1186/s12935-022-02510-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Accepted: 02/02/2022] [Indexed: 12/23/2022] Open
Abstract
Background Despite of a multimodal approach, recurrences can hardly be prevented in glioblastoma. This may be in part due to so called glioma stem cells. However, there is no established marker to identify these stem cells. Methods Paired samples from glioma patients were analyzed by immunohistochemistry for expression of the following stem cell markers: CD133, Musashi, Nanog, Nestin, octamer-binding transcription factor 4 (Oct4), and sex determining region Y-box 2 (Sox2). In addition, the expression of osteopontin (OPN) was investigated. The relative number of positively stained cells was determined. By means of Kaplan–Meier analysis, a possible association with overall survival by marker expression was investigated. Results Sixty tissue samples from 30 patients (17 male, 13 female) were available for analysis. For Nestin, Musashi and OPN a significant increase was seen. There was also an increase (not significant) for CD133 and Oct4. Patients with mutated Isocitrate Dehydrogenase-1/2 (IDH-1/2) status had a reduced expression for CD133 and Nestin in their recurrent tumors. Significant correlations were seen for CD133 and Nanog between OPN in the primary and recurrent tumor and between CD133 and Nestin in recurrent tumors. By confocal imaging we could demonstrate a co-expression of CD133 and Nestin within recurrent glioma cells. Patients with high CD133 expression had a worse prognosis (22.6 vs 41.1 months, p = 0.013). A similar trend was seen for elevated Nestin levels (24.9 vs 41.1 months, p = 0.08). Conclusions Most of the evaluated markers showed an increased expression in their recurrent tumor. CD133 and Nestin were associated with survival and are candidate markers for further clinical investigation. Supplementary Information The online version contains supplementary material available at 10.1186/s12935-022-02510-4.
Collapse
|
5
|
Yang M, Ma J, Chu Z, Cao X, Lu K, Shi X, Tong L, Yan C, Liu H, Wang X, Xiao S, Yang Z. Musashi1 inhibit the release of Newcastle disease viruses through preventing apoptosis of DF-1 cells. Poult Sci 2021; 100:101105. [PMID: 34062443 PMCID: PMC8173301 DOI: 10.1016/j.psj.2021.101105] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2020] [Revised: 02/19/2021] [Accepted: 02/27/2021] [Indexed: 12/22/2022] Open
Abstract
The efficient proliferation of Newcastle disease virus (NDV) depends on its inhibition of host cell innate immunity. V protein acts as a nonstructural protein which plays a significant role in virus replication, whereas its function remains to be further explored. In this study, Musashi RNA binding protein 1 (MSI1) was selected and its interaction with V protein was further verified by Co-immunoprecipitation (Co-IP) and Immuno-colocalization test. Through the transfection of pCMV-HA-MSI1 in DF-1 cells, the overexpression of MSI1 reduced virus particles in the cell supernatant but not reduced mRNA and virus protein in cells pellet, which suggests that MSI1may act as a new antiviral molecule by inhibiting viral release. Cell early apoptosis was detected by flow cytometry (FCM), the result shows that overexpression of MSI1 inhibit cell apoptosis, implying MSI1 Inhibit virus release may through this way. Taken together, MSI1 and NDV V protein has a detectable interaction, and may block apoptosis to inhibit the release of NDV. However, this is the first report about the interaction between MSI1 and V protein of NDV that can inhibit the NDV replicated.
Collapse
Affiliation(s)
- Mengqing Yang
- College of Veterinary Medicine, Northwest A & F University, Yangling, Shaanxi 712100, China
| | - Jiangang Ma
- College of Veterinary Medicine, Northwest A & F University, Yangling, Shaanxi 712100, China
| | - Zhili Chu
- School of Basic Medical Sciences, Xinxiang Medical University, Xinxiang, Henan 453003, China
| | - Xuhong Cao
- College of Veterinary Medicine, Northwest A & F University, Yangling, Shaanxi 712100, China
| | - Kejia Lu
- College of Veterinary Medicine, Northwest A & F University, Yangling, Shaanxi 712100, China
| | - Xiaolei Shi
- College of Veterinary Medicine, Northwest A & F University, Yangling, Shaanxi 712100, China
| | - Lina Tong
- College of Veterinary Medicine, Northwest A & F University, Yangling, Shaanxi 712100, China
| | - Chuanqi Yan
- Bureau of Agriculture and Rural Affairs of Huangdao, Qingdao, Shandong 266400, China
| | - Haijin Liu
- College of Veterinary Medicine, Northwest A & F University, Yangling, Shaanxi 712100, China
| | - Xinglong Wang
- College of Veterinary Medicine, Northwest A & F University, Yangling, Shaanxi 712100, China
| | - Sa Xiao
- College of Veterinary Medicine, Northwest A & F University, Yangling, Shaanxi 712100, China
| | - Zengqi Yang
- College of Veterinary Medicine, Northwest A & F University, Yangling, Shaanxi 712100, China.
| |
Collapse
|
6
|
Forouzanfar M, Lachinani L, Dormiani K, Nasr-Esfahani MH, Gure AO, Ghaedi K. Intracellular functions of RNA-binding protein, Musashi1, in stem and cancer cells. Stem Cell Res Ther 2020; 11:193. [PMID: 32448364 PMCID: PMC7245930 DOI: 10.1186/s13287-020-01703-w] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Revised: 03/31/2020] [Accepted: 05/05/2020] [Indexed: 12/13/2022] Open
Abstract
RNA-binding protein, musashi1 (MSI1), is a main protein in asymmetric cell division of the sensory organ precursor cells, whereas its expression is reported to be upregulated in cancers. This protein is a critical element in proliferation of stem and cancer stem cells, which acts through Wnt and Notch signaling pathways. Moreover, MSI1 modulates malignancy and chemoresistance of lung cancer cells via activating the Akt signaling. Due to the main role of MSI1 in metastasis and cancer development, MSI1 would be an appropriate candidate for cancer therapy. Downregulation of MSI1 inhibits proliferation of cancer stem cells and reduces the growth of solid tumors in several cancers. On the other hand, MSI1 expression is regulated by microRNAs in such a way that several different tumor suppressor miRNAs negatively regulate oncogenic MSI1 and inhibit migration and tumor metastasis. The aim of this review is summarizing the role of MSI1 in stem cell proliferation and cancer promotion.
Collapse
Affiliation(s)
- Mahboobeh Forouzanfar
- Department of Cell and Molecular Biology and Microbiology, Faculty of Biological Science and Technology, University of Isfahan, Hezar Jerib Ave., Azadi Square, Isfahan, P.O. Code 81746, Iran
| | - Liana Lachinani
- Department of Molecular Biotechnology, Cell Science Research Center, Royan Institute for Biotechnology, ACECR, Isfahan, P.O. Code 816513-1378, Iran
| | - Kianoush Dormiani
- Department of Molecular Biotechnology, Cell Science Research Center, Royan Institute for Biotechnology, ACECR, Isfahan, P.O. Code 816513-1378, Iran.
| | - Mohammad Hossein Nasr-Esfahani
- Department of Molecular Biotechnology, Cell Science Research Center, Royan Institute for Biotechnology, ACECR, Isfahan, P.O. Code 816513-1378, Iran. .,Department of Cellular Biotechnology, Cell Science Research Center, Royan Institute for Biotechnology, ACECR, Isfahan, Iran.
| | - Ali Osmay Gure
- Department of Molecular Biology and Genetics, Faculty of Science, Bilkent University, Ankara, Turkey
| | - Kamran Ghaedi
- Department of Cell and Molecular Biology and Microbiology, Faculty of Biological Science and Technology, University of Isfahan, Hezar Jerib Ave., Azadi Square, Isfahan, P.O. Code 81746, Iran. .,Department of Cellular Biotechnology, Cell Science Research Center, Royan Institute for Biotechnology, ACECR, Isfahan, Iran.
| |
Collapse
|
7
|
Doll CA, Yergert KM, Appel BH. The RNA binding protein fragile X mental retardation protein promotes myelin sheath growth. Glia 2019; 68:495-508. [PMID: 31626382 DOI: 10.1002/glia.23731] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Revised: 09/20/2019] [Accepted: 09/22/2019] [Indexed: 12/13/2022]
Abstract
During development, oligodendrocytes in the central nervous system extend a multitude of processes that wrap axons with myelin. The highly polarized oligodendrocytes generate myelin sheaths on many different axons, which are far removed from the cell body. Neurons use RNA binding proteins to transport, stabilize, and locally translate mRNA in distal domains of neurons. Local synthesis of synaptic proteins during neurodevelopment facilitates the rapid structural and functional changes underlying neural plasticity and avoids extensive protein transport. We hypothesize that RNA binding proteins also regulate local mRNA regulation in oligodendrocytes to promote myelin sheath growth. Fragile X mental retardation protein (FMRP), an RNA binding protein that plays essential roles in the growth and maturation of neurons, is also expressed in oligodendrocytes. To determine whether oligodendrocytes require FMRP for myelin sheath development, we examined fmr1-/- mutant zebrafish and drove FMR1 expression specifically in oligodendrocytes. We found oligodendrocytes in fmr1-/- mutants developed myelin sheaths of diminished length, a phenotype that can be autonomously rescued in oligodendrocytes with FMR1 expression. Myelin basic protein (Mbp), an essential myelin protein, was reduced in myelin tracts of fmr1-/- mutants, but loss of FMRP function did not impact the localization of mbpa transcript in myelin. Finally, expression of FMR1-I304N, a missense allele that abrogates FMRP association with ribosomes, failed to rescue fmr1-/- mutant sheath growth and induced short myelin sheaths in oligodendrocytes of wild-type larvae. Taken together, these data suggest that FMRP promotes sheath growth through local regulation of translation.
Collapse
Affiliation(s)
- Caleb A Doll
- Department of Pediatrics, University of Colorado School of Medicine, Aurora, Colorado
| | - Katie M Yergert
- Department of Pediatrics, University of Colorado School of Medicine, Aurora, Colorado
| | - Bruce H Appel
- Department of Pediatrics, University of Colorado School of Medicine, Aurora, Colorado
| |
Collapse
|
8
|
Xiao R, Yu Y, Shen S, Liu F, Kuang R. Musashi1 promotes tumor metastasis and is a prognostic marker for renal carcinoma. INTERNATIONAL JOURNAL OF CLINICAL AND EXPERIMENTAL PATHOLOGY 2019; 12:313-319. [PMID: 31933747 PMCID: PMC6944027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 05/29/2017] [Accepted: 07/14/2017] [Indexed: 06/10/2023]
Abstract
BACKGROUND Musashi1 (MSI1) has been reported to be involved in cancer development and progression. The biologic role of MSI1 in renal cell carcinoma (RCC), however, remains unknown. METHODS Expression of MSI1 in normal kidney cells and kidney cancer cells were measured by real-time PCR. In addition, MSI1 expression in 20 paired kidney cancer and non-cancerous tissues were quantified using real-time PCR. Furthermore, the expression of MSI1 in 115 kidney cancer samples was detected to analyze the correlations between MSI1 expression and the clinicopathological features of RCC patients. The biological function of MSI1 on tumor cell invasion and migration were explored through wound healing and transwell migration assays. RESULTS MSI1 was significantly upregulated in renal cancer cells and tissues compared with normal kidney cells and tissues. High levels of MSI1 were positively associated with tumor stage (P=0.002) and distant metastasis (P=0.013) of RCC patients. Patients with higher MSI1 expression had a significantly poorer overall and recurrence-free survival time (P=0.019 and P=0.012, respectively) than patients with low MSI1 expression. Multivariate analysis showed that MSI1 overexpression was an independent prognostic indicator (P=0.009 and P=0.015, respectively) for the survival of RCC patients. Ablation of MSI1 inhibited the invasion and metastasis of renal cancer cells. CONCLUSION Our results suggest that MSI1 expression is upregulated in RCC, and that MSI1 plays an important role in promoting cell invasion and metastasis of RCC.
Collapse
Affiliation(s)
- Ruihai Xiao
- Department of Urology, The Second Affiliated Hospital of Nanchang University Nanchang, Jiangxi Province, People's Republic of China
| | - Yi Yu
- Department of Urology, The Second Affiliated Hospital of Nanchang University Nanchang, Jiangxi Province, People's Republic of China
| | - Shaochen Shen
- Department of Urology, The Second Affiliated Hospital of Nanchang University Nanchang, Jiangxi Province, People's Republic of China
| | - Fei Liu
- Department of Urology, The Second Affiliated Hospital of Nanchang University Nanchang, Jiangxi Province, People's Republic of China
| | - Renrui Kuang
- Department of Urology, The Second Affiliated Hospital of Nanchang University Nanchang, Jiangxi Province, People's Republic of China
| |
Collapse
|
9
|
RNA regulation went wrong in neurodevelopmental disorders: The example of Msi/Elavl RNA binding proteins. Int J Dev Neurosci 2016; 55:124-130. [PMID: 26796049 DOI: 10.1016/j.ijdevneu.2016.01.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2015] [Revised: 01/06/2016] [Accepted: 01/07/2016] [Indexed: 11/20/2022] Open
Abstract
RNA regulation participates in many aspects of brain development. There is substantial evidence that RNA dysregulation is critical in the pathogenesis of neurodevelopmental disorders, neurological diseases, and cancer. Several gene families encode RNA-binding proteins (RNABPs) that bind directly to RNA and orchestrate the post-transcriptional regulation of gene expression, including pre-mRNA splicing, stability, and poly(A) site usage. Among neural RNABPs, the Elavl and Msi families are the focus of neuronal development research owing to their hierarchical expression pattern: Msi1 is expressed in neural progenitor/stem cells, Elavl2 is expressed in early neuronal progenitors to mature neurons, and Elavl3/4 expression begins slightly later, during cortical neuron development. Traditional biochemical analyses provide mechanistic insight into RNA regulation by these RNABPs, and Drosophila and mouse genetic studies support a relationship between these RNABPs and several neurodevelopmental disorders. In addition, a recent cohort analysis of the human genome shows that genetic mutations and SNPs in these RNABPs are associated with various neurological disorders. Newly emerged technologies assess transcriptome-wide RNA-protein interactions in vivo. These technologies, combined with classical genetics methods, provide new insight into Elavl and Msi, not only with respect to their neurodevelopmental functions, but also their roles in several diseases. We review recent discoveries related to the two RNABP families in brain development and disease.
Collapse
|
10
|
Msi1 promotes tumor growth and cell proliferation by targeting cell cycle checkpoint proteins p21, p27 and p53 in cervical carcinomas. Oncotarget 2015; 5:10870-85. [PMID: 25362645 PMCID: PMC4279416 DOI: 10.18632/oncotarget.2539] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2014] [Accepted: 09/28/2014] [Indexed: 01/08/2023] Open
Abstract
Musashi RNA-binding protein1 (Msi1), a member of the RNA-binding protein family, has been reported to be a diagnostic marker and potential therapeutic target in some cancers, its function in cervical cancer remains unknown. In this study, we found Msi1 was highly expressed in cervical cancer tissues, and over-expressing Msi1 in cervical cancer cells enhanced tumor formation and cell proliferation and accelerated cells into the S phase. Whereas, down-regulating Msi1 by shRNA in cervical cancer cells inhibited tumor formation and cell proliferation and slowed cell into the S phase, suggesting that Msi1 might act as cell cycle regulator. Immunohistochemistry assay showed the negative correlation between Msi1 and p21, p27 and p53, suggesting that Msi1 might regulate these cycle regulators in cervical cancer. Moreover, the expression of the p21, p27 and p53 proteins were down-regulated in Msi1 overexpressing cervical cancer cells and up-regulated in shMsi1 cervical cancer cells. Luciferase assays and RNA-protein binding assays confirmed that Msi1 could bind to the mRNA 3′UTRs of p21, p27 and p53 and suppress the translation of these proteins. Our findings provide new evidence that Msi1 might promote cell proliferation by accelerating the cell cycle by directly targeting p21, p27 and p53.
Collapse
|
11
|
Zearfoss NR, Deveau LM, Clingman CC, Schmidt E, Johnson ES, Massi F, Ryder SP. A conserved three-nucleotide core motif defines Musashi RNA binding specificity. J Biol Chem 2014; 289:35530-41. [PMID: 25368328 DOI: 10.1074/jbc.m114.597112] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Musashi (MSI) family proteins control cell proliferation and differentiation in many biological systems. They are overexpressed in tumors of several origins, and their expression level correlates with poor prognosis. MSI proteins control gene expression by binding RNA and regulating its translation. They contain two RNA recognition motif (RRM) domains, which recognize a defined sequence element. The relative contribution of each nucleotide to the binding affinity and specificity is unknown. We analyzed the binding specificity of three MSI family RRM domains using a quantitative fluorescence anisotropy assay. We found that the core element driving recognition is the sequence UAG. Nucleotides outside of this motif have a limited contribution to binding free energy. For mouse MSI1, recognition is determined by the first of the two RRM domains. The second RRM adds affinity but does not contribute to binding specificity. In contrast, the recognition element for Drosophila MSI is more extensive than the mouse homolog, suggesting functional divergence. The short nature of the binding determinant suggests that protein-RNA affinity alone is insufficient to drive target selection by MSI family proteins.
Collapse
Affiliation(s)
- N Ruth Zearfoss
- From the Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, Massachusetts 01605
| | - Laura M Deveau
- From the Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, Massachusetts 01605
| | - Carina C Clingman
- From the Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, Massachusetts 01605
| | - Eric Schmidt
- From the Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, Massachusetts 01605
| | - Emily S Johnson
- From the Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, Massachusetts 01605
| | - Francesca Massi
- From the Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, Massachusetts 01605
| | - Sean P Ryder
- From the Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, Massachusetts 01605
| |
Collapse
|
12
|
Clingman CC, Deveau LM, Hay SA, Genga RM, Shandilya SMD, Massi F, Ryder SP. Allosteric inhibition of a stem cell RNA-binding protein by an intermediary metabolite. eLife 2014; 3. [PMID: 24935936 PMCID: PMC4094780 DOI: 10.7554/elife.02848] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2014] [Accepted: 06/15/2014] [Indexed: 01/22/2023] Open
Abstract
Gene expression and metabolism are coupled at numerous levels. Cells must sense and respond to nutrients in their environment, and specialized cells must synthesize metabolic products required for their function. Pluripotent stem cells have the ability to differentiate into a wide variety of specialized cells. How metabolic state contributes to stem cell differentiation is not understood. In this study, we show that RNA-binding by the stem cell translation regulator Musashi-1 (MSI1) is allosterically inhibited by 18-22 carbon ω-9 monounsaturated fatty acids. The fatty acid binds to the N-terminal RNA Recognition Motif (RRM) and induces a conformational change that prevents RNA association. Musashi proteins are critical for development of the brain, blood, and epithelium. We identify stearoyl-CoA desaturase-1 as a MSI1 target, revealing a feedback loop between ω-9 fatty acid biosynthesis and MSI1 activity. We propose that other RRM proteins could act as metabolite sensors to couple gene expression changes to physiological state.
Collapse
Affiliation(s)
- Carina C Clingman
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, United States
| | - Laura M Deveau
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, United States
| | - Samantha A Hay
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, United States
| | - Ryan M Genga
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, United States
| | - Shivender M D Shandilya
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, United States
| | - Francesca Massi
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, United States
| | - Sean P Ryder
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, United States
| |
Collapse
|
13
|
Xapelli S, Agasse F, Grade S, Bernardino L, Ribeiro FF, Schitine CS, Heimann AS, Ferro ES, Sebastião AM, De Melo Reis RA, Malva JO. Modulation of subventricular zone oligodendrogenesis: a role for hemopressin? Front Cell Neurosci 2014; 8:59. [PMID: 24578683 PMCID: PMC3936357 DOI: 10.3389/fncel.2014.00059] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2013] [Accepted: 02/07/2014] [Indexed: 11/13/2022] Open
Abstract
Neural stem cells (NSCs) from the subventricular zone (SVZ) have been indicated as a source of new oligodendrocytes to use in regenerative medicine for myelin pathologies. Indeed, NSCs are multipotent cells that can self-renew and differentiate into all neural cell types of the central nervous system. In normal conditions, SVZ cells are poorly oligodendrogenic, nevertheless their oligodendrogenic potential is boosted following demyelination. Importantly, progressive restriction into the oligodendrocyte fate is specified by extrinsic and intrinsic factors, endocannabinoids being one of these factors. Although a role for endocannabinoids in oligodendrogenesis has already been foreseen, selective agonists and antagonists of cannabinoids receptors produce severe adverse side effects. Herein, we show that hemopressin (Hp), a modulator of CB1 receptors, increased oligodendroglial differentiation in SVZ neural stem/progenitor cell cultures derived from neonatal mice. The original results presented in this work suggest that Hp and derivates may be of potential interest for the development of future strategies to treat demyelinating diseases.
Collapse
Affiliation(s)
- Sara Xapelli
- Center for Neuroscience and Cell Biology of Coimbra, University of Coimbra Coimbra, Portugal ; Institute of Pharmacology and Neurosciences, Faculty of Medicine, University of Lisbon Lisboa, Portugal ; Unit of Neurosciences, Institute of Molecular Medicine, University of Lisbon Lisboa, Portugal
| | - Fabienne Agasse
- Center for Neuroscience and Cell Biology of Coimbra, University of Coimbra Coimbra, Portugal
| | - Sofia Grade
- Center for Neuroscience and Cell Biology of Coimbra, University of Coimbra Coimbra, Portugal ; Institute for Stem Cell Research, Helmholtz Centre Munich, German Research Centre for Environmental Health Neuherberg, Germany ; Department of Physiological Genomics, Faculty of Medicine, Ludwig-Maximilians University of Munich Munich, Germany
| | - Liliana Bernardino
- Center for Neuroscience and Cell Biology of Coimbra, University of Coimbra Coimbra, Portugal ; Health Sciences Research Center, University of Beira Interior Covilhã, Portugal
| | - Filipa F Ribeiro
- Institute of Pharmacology and Neurosciences, Faculty of Medicine, University of Lisbon Lisboa, Portugal ; Unit of Neurosciences, Institute of Molecular Medicine, University of Lisbon Lisboa, Portugal
| | - Clarissa S Schitine
- Neurochemistry Laboratory, Biophysics Institute Carlos Chagas Filho, Federal University of Rio de Janeiro Rio de Janeiro, Brazil
| | | | - Emer S Ferro
- Departamento de Biologia Celular e do Desenvolvimento, Instituto de Ciências Biomédicas São Paulo, Brazil
| | - Ana M Sebastião
- Institute of Pharmacology and Neurosciences, Faculty of Medicine, University of Lisbon Lisboa, Portugal ; Unit of Neurosciences, Institute of Molecular Medicine, University of Lisbon Lisboa, Portugal
| | - Ricardo A De Melo Reis
- Neurochemistry Laboratory, Biophysics Institute Carlos Chagas Filho, Federal University of Rio de Janeiro Rio de Janeiro, Brazil
| | - João O Malva
- Center for Neuroscience and Cell Biology of Coimbra, University of Coimbra Coimbra, Portugal ; Center of Investigation in Environment, Genetics and Oncobiology, Institute for Biomedical Imaging and Life Sciences, Faculty of Medicine, University of Coimbra Coimbra, Portugal
| |
Collapse
|
14
|
Franklin RJM, Gallo V. The translational biology of remyelination: past, present, and future. Glia 2014; 62:1905-15. [PMID: 24446279 DOI: 10.1002/glia.22622] [Citation(s) in RCA: 126] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2013] [Revised: 11/07/2013] [Accepted: 12/10/2013] [Indexed: 01/01/2023]
Abstract
Amongst neurological diseases, multiple sclerosis (MS) presents an attractive target for regenerative medicine. This is because the primary pathology, the loss of myelin-forming oligodendrocytes, can be followed by a spontaneous and efficient regenerative process called remyelination. While cell transplantation approaches have been explored as a means of replacing lost oligodendrocytes, more recently therapeutic approaches that target the endogenous regenerative process have been favored. This is in large part due to our increasing understanding of (1) the cell types within the adult brain that are able to generate new oligodendrocytes, (2) the mechanisms and pathways by which this achieved, and (3) an emerging awareness of the reasons why remyelination efficiency eventually fails. Here we review some of these advances and also highlight areas where questions remain to be answered in both the biology and translational potential of this important regenerative process.
Collapse
Affiliation(s)
- Robin J M Franklin
- Wellcome Trust-MRC Cambridge Stem Cell Institute and Department of Veterinary Medicine, University of Cambridge, Cambridge, CB3 0ES, United Kingdom
| | | |
Collapse
|
15
|
Dobson NR, Moore RT, Tobin JE, Armstrong RC. Leukemia/lymphoma-related factor regulates oligodendrocyte lineage cell differentiation in developing white matter. Glia 2012; 60:1378-90. [PMID: 22615173 DOI: 10.1002/glia.22356] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2012] [Accepted: 04/25/2012] [Indexed: 11/10/2022]
Abstract
Leukemia/lymphoma-related factor (LRF) is a zinc-finger transcription factor that regulates differentiation and oncogenesis in multiple tissues and cell lineages. The potential role for LRF in cells of the CNS has not been examined to date. This study shows prominent nuclear expression of LRF in diverse neuronal populations and in oligodendrocytes. We focused on examining the function of LRF during the transition from oligodendrocyte progenitor (OP) to mature oligodendrocyte that is associated with myelination in the postnatal spinal cord. During spinal cord myelination, LRF is expressed in only a minority of OP cells whereas most mature oligodendrocytes exhibited nuclear LRF immunoreactivity. Mice with floxed alleles of the Zbtb7a gene, which encodes for LRF protein, were used for in vivo analysis of LRF function. Lentiviral driven Cre recombinase inactivation of LRF at postnatal day 7 reduced the proportion of OP cells that differentiated into mature oligodendrocytes by postnatal day 28. Astrocyte populations were not altered by LRF deletion in the same tissues. These results indicate that LRF deletion reduces differentiation within the oligodendrocyte lineage and does not alter OP lineage choice. In vitro analysis confirmed a specific effect of LRF on OP differentiation. In neonatal OP cultures, RNA interference targeting LRF inhibited OP differentiation while LRF transduction was sufficient to induce differentiation into oligodendrocytes. These results support a critical role for LRF in transcriptional control of differentiation in oligodendrocyte lineage cells during developmental myelination in the CNS.
Collapse
Affiliation(s)
- Nicole R Dobson
- Department of Pediatrics, Uniformed Services University of Health Sciences, Bethesda, MD 20814, USA
| | | | | | | |
Collapse
|
16
|
Li D, Peng X, Yan D, Tang H, Huang F, Yang Y, Peng Z. Msi-1 is a predictor of survival and a novel therapeutic target in colon cancer. Ann Surg Oncol 2011; 18:2074-83. [PMID: 21442350 DOI: 10.1245/s10434-011-1567-9] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2010] [Indexed: 01/29/2023]
Abstract
BACKGROUND Musashi1 (Msi-1), a neural RNA-binding protein, plays an important role in regulating cell differentiation in precursor cells. Recently, aberrant expression of Msi-1 has been detected in several malignancies. However, its role in the progression of colon cancer is largely unknown. MATERIALS AND METHODS We used Western blotting to examine Msi-1 protein expression in 8 cases of primary colon cancer lesions and paired normal colonic mucosa. Msi-1 expression and clinicopathological significance were determined by immunohistochemical staining in a tissue microarray (TMA) containing 203 cases of primary colon cancer paired with noncancerous tissue and 66 lymph node metastasis (LNM) tissues. RNAi was used to analyze the biological function of Msi-1 in vitro. RESULTS LNM tissue exhibited a striking increase in Msi-1 expression when compared with primary colon cancer and adjacent normal mucosa (87.9% vs. 64.5% vs. 16.7%, P < .001). Overexpression of Msi-1 was associated with higher clinical stage, T stage, lymph node metastasis, presence of distant metastasis, and Ki-67 positivity. Msi-1 served as an independent prognostic marker whose expression levels correlated with poorer metastasis-free survival (MFS) (HR 5.4; P < .001) and poorer overall survival (OS) (HR 3.8; P < .001). Msi-1 silencing significantly inhibited proliferation ability and attenuated the migration and invasion activity of colon cancer cells. CONCLUSIONS Our study provides the basis to explore the use of Msi-1 as a novel prognostic biomarker in colon cancer patients. Aberrant overexpression of Msi-1 during metastasis of colon cancer also suggests that it is a potential therapeutic target.
Collapse
Affiliation(s)
- Dawei Li
- Department of General Surgery, Shanghai Jiaotong University, Shanghai, People's Republic of China
| | | | | | | | | | | | | |
Collapse
|
17
|
Nikpour P, Baygi ME, Steinhoff C, Hader C, Luca AC, Mowla SJ, Schulz WA. The RNA binding protein Musashi1 regulates apoptosis, gene expression and stress granule formation in urothelial carcinoma cells. J Cell Mol Med 2010; 15:1210-24. [PMID: 20477901 PMCID: PMC3822633 DOI: 10.1111/j.1582-4934.2010.01090.x] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The RNA-binding protein Musashi1 (MSI1) is a marker of progenitor cells in the nervous system functioning as a translational repressor. We detected MSI1 mRNA in several bladder carcinoma cell lines, but not in cultured normal uroepithelial cells, whereas the paralogous MSI2 gene was broadly expressed. Knockdown of MSI1 expression by siRNA induced apoptosis and a severe decline in cell numbers in 5637 bladder carcinoma cells. Microarray analysis of gene expression changes after MSI1 knockdown significantly up-regulated 735 genes, but down-regulated only 31. Up-regulated mRNAs contained a highly significantly greater number and density of Musashi binding sites. Therefore, a much larger set of mRNAs may be regulated by Musashi1, which may affect not only their translation, but also their turnover. The study confirmed p21CIP1 and Numb proteins as targets of Musashi1, suggesting additionally p27KIP1 in cell-cycle regulation and Jagged-1 in Notch signalling. A significant number of up-regulated genes encoded components of stress granules (SGs), an organelle involved in translational regulation and mRNA turnover, and impacting on apoptosis. Accordingly, heat shock induced SG formation was augmented by Musashi1 down-regulation. Our data show that ectopic MSI1 expression may contribute to tumorigenesis in selected bladder cancers through multiple mechanisms and reveal a previously unrecognized function of Musashi1 in the regulation of SG formation.
Collapse
Affiliation(s)
- Parvaneh Nikpour
- Department of Genetics, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran
| | | | | | | | | | | | | |
Collapse
|
18
|
de Sousa Abreu R, Sanchez-Diaz PC, Vogel C, Burns SC, Ko D, Burton TL, Vo DT, Chennasamudaram S, Le SY, Shapiro BA, Penalva LOF. Genomic analyses of musashi1 downstream targets show a strong association with cancer-related processes. J Biol Chem 2009; 284:12125-35. [PMID: 19258308 DOI: 10.1074/jbc.m809605200] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Musashi1 (Msi1) is a highly conserved RNA-binding protein with pivotal functions in stem cell maintenance, nervous system development, and tumorigenesis. Despite its importance, only three direct mRNA targets have been characterized so far: m-numb, CDKN1A, and c-mos. Msi1 has been shown to affect their translation by binding to short elements located in the 3'-untranslated region. To better understand Msi1 functions, we initially performed an RIP-Chip analysis in HEK293T cells; this method consists of isolation of specific RNA-protein complexes followed by identification of the RNA component via microarrays. A group of 64 mRNAs was found to be enriched in the Msi1-associated population compared with controls. These genes belong to two main functional categories pertinent to tumorigenesis: 1) cell cycle, cell proliferation, cell differentiation, and apoptosis and 2) protein modification (including ubiquitination and ubiquitin cycle). To corroborate our findings, we examined the impact of Msi1 expression on both mRNA (transcriptomic) and protein (proteomic) expression levels. Genes whose mRNA levels were affected by Msi1 expression have a Gene Ontology distribution similar to RIP-Chip results, reinforcing Msi1 participation in cancer-related processes. The proteomics study revealed that Msi1 can have either positive or negative effects on gene expression of its direct targets. In summary, our results indicate that Msi1 affects a network of genes and could function as a master regulator during development and tumor formation.
Collapse
Affiliation(s)
- Raquel de Sousa Abreu
- Children's Cancer Research Institute, University of Texas Health Science Center at San Antonio, Department of Cellular and Structural Biology, San Antonio, TX 78229-390, USA
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
19
|
Oligodendrocyte differentiation and implantation: new insights for remyelinating cell therapy. Curr Opin Neurol 2008; 21:607-14. [PMID: 18769257 DOI: 10.1097/wco.0b013e32830f1e50] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
PURPOSE OF REVIEW Recent research on oligodendrocyte development has yielded new insights on the involvement of morphogens and differentiation factors in oligodendrogenesis. This knowledge has improved strategies to control neural stem cell-derived oligodendrocyte differentiation and functional maturation in vitro. In this review, we highlight the current knowledge on oligodendrocyte differentiation and discuss the novel possibilities of neural stem cell-derived oligodendrocytes for graft-based remyelination therapy, for example, for multiple sclerosis. RECENT FINDINGS Detailed insight into the cellular and molecular processes of embryonic and adult oligodendrogenesis has extended considerably in the past 2 years. Application of extrinsic factors and manipulation of intrinsic factors in neural stem cells have yielded convincing oligodendrocyte differentiation strategies. In addition, the recent groundbreaking developments regarding induced pluripotent stem cells generated from easily accessible somatic cells seem to offer an almost inexhaustible source for transplantable, autologous neural stem cells. Moreover, new approaches to optimize the implantation site for oligodendrocyte survival and functionality have improved the feasibility of stem cell-based oligodendrocyte replacement therapy. SUMMARY Loss of myelin in demyelinating diseases is only partly restored by endogenous oligodendrocyte precursor cells. Application of optimally functional, neural stem cell-derived oligodendrocyte precursors at the lesion site has become a realistic therapeutic approach to promote the remyelination process.
Collapse
|
20
|
Sanchez-Diaz PC, Burton TL, Burns SC, Hung JY, Penalva LOF. Musashi1 modulates cell proliferation genes in the medulloblastoma cell line Daoy. BMC Cancer 2008; 8:280. [PMID: 18826648 PMCID: PMC2572071 DOI: 10.1186/1471-2407-8-280] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2008] [Accepted: 09/30/2008] [Indexed: 01/12/2023] Open
Abstract
BACKGROUND Musashi1 (Msi1) is an RNA binding protein with a central role during nervous system development and stem cell maintenance. High levels of Msi1 have been reported in several malignancies including brain tumors thereby associating Msi1 and cancer. METHODS We used the human medulloblastoma cell line Daoy as model system in this study to knock down the expression of Msi1 and determine the effects upon soft agar growth and neurophere formation. Quantitative RT-PCR was conducted to evaluate the expression of cell proliferation, differentiation and survival genes in Msi1 depleted Daoy cells. RESULTS We observed that MSI1 expression was elevated in Daoy cells cultured as neurospheres compared to those grown as monolayer. These data indicated that Msi1 might be involved in regulating proliferation in cancer cells. Here we show that shRNA mediated Msi1 depletion in Daoy cells notably impaired their ability to form colonies in soft agar and to grow as neurospheres in culture. Moreover, differential expression of a group of Notch, Hedgehog and Wnt pathway related genes including MYCN, FOS, NOTCH2, SMO, CDKN1A, CCND2, CCND1, and DKK1, was also found in the Msi1 knockdown, demonstrating that Msi1 modulated the expression of a subset of cell proliferation, differentiation and survival genes in Daoy. CONCLUSION Our data suggested that Msi1 may promote cancer cell proliferation and survival as its loss seems to have a detrimental effect in the maintenance of medulloblastoma cancer cells. In this regard, Msi1 might be a positive regulator of tumor progression and a potential target for therapy.
Collapse
Affiliation(s)
- Patricia C Sanchez-Diaz
- Greehey Children's Cancer Research Institute, University of Texas Health Science Center at San Antonio, TX, USA.
| | | | | | | | | |
Collapse
|
21
|
Post-transcriptional regulation of myelin formation. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2008; 1779:486-94. [PMID: 18590840 DOI: 10.1016/j.bbagrm.2008.06.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2008] [Revised: 05/15/2008] [Accepted: 06/03/2008] [Indexed: 12/21/2022]
Abstract
Myelin is a specialized structure of the nervous system that both enhances electrical conductance and protects neurons from degeneration. In the central nervous system, extensively polarized oligodendrocytes form myelin by wrapping cellular processes in a spiral pattern around neuronal axons. Myelin formation requires the oligodendrocyte to regulate gene expression in response to changes in its extracellular environment. Because these changes occur at a distance from the cell body, post-transcriptional control of gene expression allows the cell to fine-tune its response. Here, we review the RNA-binding proteins that control myelin formation in the brain, highlighting the molecular mechanisms by which they control gene expression and drawing parallels from studies in other cell types.
Collapse
|