Search results for "Homeobox"
showing 10 items of 117 documents
De novo t(12;17)(p13.3;q21.3) translocation with a breakpoint near the 5' end of the HOXB gene cluster in a patient with developmental delay and skel…
2007
A boy with severe mental retardation, funnel chest, bell-shaped thorax, and hexadactyly of both feet was found to have a balanced de novo t(12;17)(p13.3;q21.3) translocation. FISH with BAC clones and long-range PCR products assessed in the human genome sequence localized the breakpoint on chromosome 17q21.3 to a 21-kb segment that lies <30 kb upstream of the HOXB gene cluster and immediately adjacent to the 3′ end of the TTLL6 gene. The breakpoint on chromosome 12 occurred within telomeric hexamer repeats and, therefore, is not likely to affect gene function directly. We propose that juxtaposition of the HOXB cluster to a repetitive DNA domain and/or separation from required cis-regulatory …
Gene expression during early embryogenesis of sea urchin: The histone and homeobox genes
1997
Transcriptional regulators are thought to play a key role in cell fate determination and territorial specification in sea urchin. Our goals are to clone transcription factors for studying embryonic development. One approach has been to use promoter binding and gene transfer technology to investigate the mechanisms of transcriptional activation and repression of the early H2A histone gene. By this analysis we identified a transcriptional activator, the MBF-1, that binds to the modulator element of the H2A gene and enhances the activity of the H2A promoter. However, the enhancer activity of the modulator and its interaction with MBF-1 also occurs at the gastrula stage when the early histone g…
Gene Expression and Epigenetic Signatures of Germ Cell-Derived Pluripotent Stem Cells and Embryonic Stem Cells
2012
Germ cell-derived Pluripotent Stem Cells (gPSCs) are pluripotent stem cells that originate from Spermatogonial Stem Cells (SSCs) of the testis. Several reports in the last few years have shown that it is possible to isolate and enrich the SSC population by different approaches and even reprogram these in vivo multipotent cells to gPSCs in vitro. As these cells could be an alternative to circumvent the ethical objections regarding the use of Embryonic Stem Cells (ESCs) for therapeutic approaches, these SSC-derived gPSCs were characterized in several studies comparatively to the gold standard of pluripotency, the ESCs. The results provide great promise that gPSCs can be of importance for pra…
Gene expression of stem cells at different stages of ontological human development.
2013
Abstract Objectives To compare multipotent mesenchymal stem cells (MSCs) obtained from chorionic villi (CV), amniotic fluid (AF) and placenta, with regard to their phenotype and gene expression, in order to understand if MSCs derived from different extra-embryonic tissues, at different stages of human ontological development, present distinct stemness characteristics. Study design MSCs obtained from 30 samples of CV, 30 of AF and 10 placentas (obtained from elective caesarean sections) were compared. MSCs at second confluence cultures were characterized by immunophenotypic analysis with flow cytometry using FACS CANTO II. The expression of the genes Oct-4 (Octamer-binding transcription fact…
MYC Activates Stem-like Cell Potential in Hepatocarcinoma by a p53-Dependent Mechanism
2014
Activation of c-MYC is an oncogenic hallmark of many cancers including liver cancer, and is associated with a variety of adverse prognostic characteristics. Despite a causative role during malignant transformation and progression in hepatocarcinogenesis, consequences of c-MYC activation for the biology of hepatic cancer stem cells (CSCs) are undefined. Here, distinct levels of c-MYC over-expression were established by using two dose-dependent tetracycline inducible systems in 4 hepatoma cell lines with different p53 mutational status. The CSCs were evaluated using side-population approach as well as standard in vitro and in vivo assays. Functional repression of p53 was achieved by lentivira…
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…
Genome Stability in Embryonic Stem Cells
2011
Paola Rebuzzini1, Maurizio Zuccotti2*, Carlo Alberto Redi1,3 and Silvia Garagna1,4,5* 1Laboratorio di Biologia dello Sviluppo, Dipartimento di Biologia Animale, Universita degli Studi di Pavia, Via Ferrata 9, 27100 Pavia, 2Sezione di Istologia ed Embriologia, Dipartimento di Medicina Sperimentale, Universita degli Studi di Parma, Via Volturno 39, 43100 Parma 3Fondazione I.R.C.C.S. Policlinico San Matteo, Piazzale Golgi, 19, 27100 Pavia 4Centro di Ricerca Interdipartimentale di Ingegneria Tissutale, Universita degli Studi di Pavia, Via Ferrata 1, 27100 Pavia 5Centro di Eccellenza in Biologia Applicata, Universita degli Studi di Pavia, Via Ferrata 9, 27100 Pavia Italy
Zfp819, a novel KRAB-zinc finger protein, interacts with KAP1 and functions in genomic integrity maintenance of mouse embryonic stem cells
2013
AbstractPluripotency is maintained by both known and unknown transcriptional regulatory networks. In the present study, we have identified Zfp819, a KRAB-zinc finger protein, as a novel pluripotency-related factor and characterized its role in pluripotent stem cells. We show that Zfp819 is expressed highly in various types of pluripotent stem cells but not in their differentiated counterparts. We identified the presence of non-canonical nuclear localization signals in particular zinc finger motifs and identified them as responsible for the nuclear localization of Zfp819. Analysis of the Zfp819 promoter region revealed the presence of a transcriptionally active chromatin signature. Moreover,…