Aspects moléculaires du cancer du sein triple négatif et les implications thérapeutiques
COLLIGNON, Joëlle ; Struman, Ingrid ; Tabruyn, Sébastien et al
in Revue Médicale de Liège (2011), 66(5-6), 393-396Detailed reference viewed: 144 (26 ULg)
Systematic chromosomal aberrations found in murine bone marrow-derived mesenchymal stem cells.
Josse, Claire ; ; Niessen, Neville-Andrew et al
in Stem Cells & Development (2010), 19(8), 1167-1173
Mesenchymal stem cells (MSCs) are studied as a cellular source for the treatment of various diseases. In this work, we isolated and cultivated murine bone marrow-derived MSCs. After a first observation of ... [more ▼]
Mesenchymal stem cells (MSCs) are studied as a cellular source for the treatment of various diseases. In this work, we isolated and cultivated murine bone marrow-derived MSCs. After a first observation of a solid tumour in a mouse injected with these cells, we systematically explored their chromosomal stability. We observed in all the cytogenetically analysed cases gross chromosomal alterations every time the MSCs went through the senescence crisis while the lymphocytes from the same animals showed a normal chromosome count. This observation was confirmed in different mouse strains, with different culture protocols, and even in short-term cultures after an hematopoietic cell negative immunodepletion performed in order to accelerate the isolation procedure. Therefore, we conclude that murine MSCs display high chromosomal instability, can generate tumours, and that care must be taken before using them for the evaluation of MSC therapeutic potential. [less ▲]Detailed reference viewed: 51 (15 ULg)
The umbilical cord matrix is a better source of mesenchymal stem cells (MSC) than the umbilical cord blood.
Zeddou, Mustapha ; Briquet, Alexandra ; Relic, Biserka et al
in Cell Biology International (2010), 34(7), 693-701
Many studies have drawn attention to the emerging role of MSC (mesenchymal stem cells) as a promising population supporting new clinical concepts in cellular therapy. However, the sources from which these ... [more ▼]
Many studies have drawn attention to the emerging role of MSC (mesenchymal stem cells) as a promising population supporting new clinical concepts in cellular therapy. However, the sources from which these cells can be isolated are still under discussion. Whereas BM (bone marrow) is presented as the main source of MSC, despite the invasive procedure related to this source, the possibility of isolating sufficient numbers of these cells from UCB (umbilical cord blood) remains controversial. Here, we present the results of experiments aimed at isolating MSC from UCB, BM and UCM (umbilical cord matrix) using different methods of isolation and various culture media that summarize the main procedures and criteria reported in the literature. Whereas isolation of MSC were successful from BM (10:10) and (UCM) (8:8), only one cord blood sample (1:15) gave rise to MSC using various culture media [DMEM (Dulbecco's modified Eagle's medium) +5% platelet lysate, DMEM+10% FBS (fetal bovine serum), DMEM+10% human UCB serum, MSCGM] and different isolation methods [plastic adherence of total MNC (mononuclear cells), CD3+/CD19+/CD14+/CD38+-depleted MNC and CD133+- or LNGFR+-enriched MNC]. MSC from UCM and BM were able to differentiate into adipocytes, osteocytes and hepatocytes. The expansion potential was highest for MSC from UCM. The two cell populations had CD90+/CD73+/CD105+ phenotype with the additional expression of SSEA4 and LNGFR for BM MSC. These results clearly exclude UCB from the list of MSC sources for clinical use and propose instead UCM as a rich, non-invasive and abundant source of MSC. [less ▲]Detailed reference viewed: 62 (15 ULg)
Oligodendrocyte development and myelinogenesis are not impaired by high concentrations of phenylalanine or its metabolites.
; ; et al
in Journal of Inherited Metabolic Disease (2010), 33(2), 113-20
Phenylketonuria (PKU) is a metabolic genetic disease characterized by deficient phenylalanine hydroxylase (PAH) enzymatic activity. Brain hypomyelination has been reported in untreated patients, but its ... [more ▼]
Phenylketonuria (PKU) is a metabolic genetic disease characterized by deficient phenylalanine hydroxylase (PAH) enzymatic activity. Brain hypomyelination has been reported in untreated patients, but its mechanism remains unclear. We therefore investigated the influence of phenylalanine (Phe), phenylpyruvate (PP), and phenylacetate (PA) on oligodendrocytes. We first showed in a mouse model of PKU that the number of oligodendrocytes is not different in corpus callosum sections from adult mutants or from control brains. Then, using enriched oligodendroglial cultures, we detected no cytotoxic effect of high concentrations of Phe, PP, or PA. Finally, we analyzed the impact of Phe, PP, and PA on the myelination process in myelinating cocultures using both an in vitro index of myelination, based on activation of the myelin basic protein (MBP) promoter, and the direct quantification of myelin sheaths by both optical measurement and a bioinformatics method. None of these parameters was affected by the increased levels of Phe or its derivatives. Taken together, our data demonstrate that high levels of Phe, such as in PKU, are unlikely to directly induce brain hypomyelination, suggesting involvement of alternative mechanisms in this myelination defect. [less ▲]Detailed reference viewed: 29 (7 ULg)
Impairment of mitochondrial functions abolishes NF-kappaB activation by an oxidative stress
Josse, Claire ; Legrand-Poels, Sylvie ; et al
in Free Radical Biology & Medicine (1998)Detailed reference viewed: 5 (0 ULg)