Search results for " STEM"
showing 10 items of 2170 documents
Isolation and characterization of Oct-4+/HLA-G+ mesenchymal stem cells from human umbilical cord matrix: differentiation potential and detection of n…
2008
The presence of multipotent cells in several adult and embryo-related tissues opened new paths for their use in regenerative medicine. Extraembryonic tissues such as umbilical cord are considered a promising source of stem cells, potentially useful in therapy. The characterization of cells from the umbilical cord matrix (Wharton''s Jelly) and amniotic membrane revealed the presence of a population of mesenchymal-like cells, sharing a set of core-markers expressed by "mesenchymal stem cells". Several reports enlightened the differentiation capabilities of these cells, even if at times the lack of an extensive characterization of surface markers and immune co-stimulators expression revealed h…
Analysis of NO synthase expression in neuronal, astroglial and fibroblast-like derivatives differen-tiating from PCC7-Mzl embryonic carcinoma cells
1999
We studied the expression of the NO synthase isoforms in an in vitro model of neural development using RT-PCR, Western blot and immu- nohistochemistry. Murine PCC7-Mzl cells (Jostock et al., Eur. J. Cell Biol. 76, 63–76,1998) differentiate in the presence of all-trans retinoic acid and dibutyryl cAMP along the neural pathway into neuron-like, fibroblast-like and astroglia-like cells. Undifferentiated cells showed immunofluorescent staining for neuronal-type NOSI and endothelial- type NOS III. This expression pattern was retained in those cells differ entiating into neurofilament- and tau protein-positive neuronal cells. Thymocyte alloantigen (Thyl.2/CD 90.2)-positive Fibroblasts, appearing …
Mutant p53 gain of function can be at the root of dedifferentiation of human osteosarcoma MG63 cells into 3AB-OS cancer stem cells
2014
Osteosarcoma is a highly metastatic tumor affecting adolescents, for which there is no second-line chemotherapy. As suggested for most tumors, its capability to overgrow is probably driven by cancer stem cells (CSCs), and finding new targets to kill CSCs may be critical for improving patient survival. TP53 is the most frequently mutated tumor suppressor gene in cancers and mutant p53 protein (mutp53) can acquire gain of function (GOF) strongly contributing to malignancy. Studies thus far have not shown p53-GOF in osteosarcoma. Here, we investigated TP53 gene status/role in 3AB-OS cells-a highly aggressive CSC line previously selected from human osteosarcoma MG63 cells-to evaluate its involv…
An Analysis of the Immunomodulatory Properties of Human Spheroids from Adipose-Derived Stem Cells
2023
Aims Current methods to induce tolerance following allotransplantation or in autoimmunity carry significant morbidity, and research is very active in investigating alternative methods which could minimize toxicity. Spheroids from adipose stem cells (SASCs) are increasingly gaining interest, they hold a great proliferative and differentiating potential. An immunomodulatory effect has not been investigated on SASCs yet. In this study, we analysed the immunomodulatory properties of SASCs and compared them to ADSCs. Main methods Adipose stem cells (SASCs and ADSCs) and peripheral blood mononuclear cells (PBMCs) were collected from healthy individuals. We analysed the cytokine production and pro…
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…