Search results for "SOX2"
showing 10 items of 48 documents
3D bioprinting of tissue units with mesenchymal stem cells, retaining their proliferative and differentiating potential, in polyphosphate-containing …
2021
Abstract The three-dimensional (3D)-printing processes reach increasing recognition as important fabrication techniques to meet the growing demands in tissue engineering. However, it is imperative to fabricate 3D tissue units, which contain cells that have the property to be regeneratively active. In most bio-inks, a metabolic energy-providing component is missing. Here a formulation of a bio-ink is described, which is enriched with polyphosphate (polyP), a metabolic energy providing physiological polymer. The bio-ink composed of a scaffold (N,O-carboxymethyl chitosan), a hydrogel (alginate) and a cell adhesion matrix (gelatin) as well as polyP substantially increases the viability and the …
A quest for initiating cells of head and neck cancer and their treatment.
2010
The biology of head and neck squamous cell carcinomas (HNSCC) and other cancers have been related to cancer stem-like cells (CSC). Specific markers, which vary considerably depending on tumor type or tissue of origin, characterize CSC. CSC are cancer initiating, sustaining and mostly quiescent. Compared to bulk tumors, CSC are less sensitive to chemo- and radiotherapy and may have low immunogenicity. Therapeutic targeting of CSC may improve clinical outcome. HNSCC has two main etiologies: human papillomavirus, a virus infecting epithelial stem cells, and tobacco and alcohol abuse. Here, current knowledge of HNSCC-CSC biology is reviewed and parallels to CSC of other origin are drawn where n…
Lineage-reprogramming of Pericyte-derived Cells of the Adult Human Brain into Induced Neurons
2014
Direct lineage-reprogramming of non-neuronal cells into induced neurons (iNs) may provide insights into the molecular mechanisms underlying neurogenesis and enable new strategies for in vitro modeling or repairing the diseased brain. Identifying brain-resident non-neuronal cell types amenable to direct conversion into iNs might allow for launching such an approach in situ, i.e. within the damaged brain tissue. Here we describe a protocol developed in the attempt of identifying cells derived from the adult human brain that fulfill this premise. This protocol involves: (1) the culturing of human cells from the cerebral cortex obtained from adult human brain biopsies; (2) the in vitro expansio…
Cyclin-dependent kinase inhibitor p21 controls adult neural stem cell expansion by regulating Sox2 gene expression.
2012
Summary In the adult brain, continual neurogenesis of olfactory neurons is sustained by the existence of neural stem cells (NSCs) in the subependymal niche. Elimination of the cyclin-dependent kinase inhibitor 1A (p21) leads to premature exhaustion of the subependymal NSC pool, suggesting a relationship between cell cycle control and long-term self-renewal, but the molecular mechanisms underlying NSC maintenance by p21 remain unexplored. Here we identify a function of p21 in the direct regulation of the expression of pluripotency factor Sox2, a key regulator of the specification and maintenance of neural progenitors. We observe that p21 directly binds a Sox2 enhancer and negatively regulate…
Sox2-Mediated Conversion of NG2 Glia into Induced Neurons in the Injured Adult Cerebral Cortex
2014
Summary The adult cerebral cortex lacks the capacity to replace degenerated neurons following traumatic injury. Conversion of nonneuronal cells into induced neurons has been proposed as an innovative strategy toward brain repair. Here, we show that retrovirus-mediated expression of the transcription factors Sox2 and Ascl1, but strikingly also Sox2 alone, can induce the conversion of genetically fate-mapped NG2 glia into induced doublecortin (DCX)+ neurons in the adult mouse cerebral cortex following stab wound injury in vivo. In contrast, lentiviral expression of Sox2 in the unlesioned cortex failed to convert oligodendroglial and astroglial cells into DCX+ cells. Neurons induced following …
Human adult periodontal ligament-derived cells integrate and differentiate after implantation into the adult mammalian brain.
2013
Previous studies suggest that neural crest (NC)-derived stem cells may reside in NC derivatives including the human periodontal ligament (hPDL). The isolation and manipulation of autologous NC-derived cells could be an accessible source of adult neural stem cells for their use in cell replacement and gene transfer to the diseased central nervous system. In this study, we examined the expression of NC markers and neural differentiation potential of hPDL-derived cells both in vitro and in vivo. In vitro we found that hPDL-derived cells expressed stem cell markers (Oct3/4, Nestin, Sox2, and Musashi-1) and a subset of NC cell markers (Slug, p75(NTR), Twist, and Sox9). hPDL-derived cells differe…
Reversible neural stem cell niche dysfunction in a model of multiple sclerosis
2011
Objective The subventricular zone (SVZ) of the brain constitutes a niche for neural stem and progenitor cells that can initiate repair after central nervous system (CNS) injury. In a relapsing-remitting model of experimental autoimmune encephalomyelitis (EAE), the neural stem cells (NSCs) become activated and initiate regeneration during acute disease, but lose this ability during the chronic phases of disease. We hypothesized that chronic microglia activation contributes to the failure of the NSC repair potential in the SVZ. Methods Using bromodeoxyuridine injections at different time points during EAE, we quantified the number of proliferating and differentiating progenitors, and evaluate…
Abstract 3056: Lung tumor spheres as in vitro platform for testing new therapeutic strategies against cancer stem cells
2018
Abstract Background: Treatment resistance is related to cancer stem cells (CSCs), a highly tumorigenic subpopulation of cells capable of growing and forming tumor spheres under non-adherent conditions. This study aimed to isolate and characterise CSCs from resected non-small cell lung cancer (NSCLC) patients' tumor-tissue and cell lines like tumor spheres and to use them as an in vitro platform for drug screening. Methods: The study was performed on tumour cells from 8 resected NSCLC patients and 12 NSCLC cell lines grown in monolayer and as spheres. The expression of 60 genes, including CSC-markers, pluripotency inducers, cell cycle regulators and components of the Notch, Wnt and Hedgehog …
Abstract 3354: Characterization of lung tumorspheres by gene expression and flow cytometry: differential expression in CSC-related markers and signal…
2016
Abstract Chemoresistance, progression and metastasis have made of lung cancer the first cause of cancer mortality. These features were linked to a subpopulation of cells, named cancer stem cells (CSCs), which remain largely unknown. The aim of this study was to isolate and characterize CSCs from lung cancer cell-lines and tumor-tissue from resectable non-small cell lung cancer (NSCLC). Methods: Tumor cells from resected NSCLC and cell lines (H1650, H1993, A549, and PC9) were grown in monolayer and as spheroids. RTqPCR was performed to analyze the mRNA expression of CSCs-related genes: CSC-markers (EPCAM1, ALDH1A1, CD166, ABCG2, CD44, CD133); pluripotency genes (KLF4, OCT4, NANOG, SOX2, MYC,…
Efficient Reprogramming of Human Fibroblasts and Blood-Derived Endothelial Progenitor Cells Using Nonmodified RNA for Reprogramming and Immune Evasion
2015
mRNA reprogramming results in the generation of genetically stable induced pluripotent stem (iPS) cells while avoiding the risks of genomic integration. Previously published mRNA reprogramming protocols have proven to be inconsistent and time-consuming and mainly restricted to fibroblasts, thereby demonstrating the need for a simple but reproducible protocol applicable to various cell types. So far there have been no published reports using mRNA to reprogram any cell type derived from human blood. Nonmodified synthetic mRNAs are immunogenic and activate cellular defense mechanisms, which can lead to cell death and inhibit mRNA translation upon repetitive transfection. Hence, to overcome RNA…