Publications by authors named "Mischael Dehoux"

Melanomas remain associated with dismal prognosis because they are naturally resistant to apoptosis and they markedly metastasize. Up-regulated expression of sodium pump alpha sub-units has previously been demonstrated when comparing metastatic to non-metastatic melanomas. Our previous data revealed that impairing sodium pump alpha1 activity by means of selective ligands, that are cardiotonic steroids, markedly impairs cell migration and kills apoptosis-resistant cancer cells.

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Narciclasine (1) is a plant growth regulator that has been previously demonstrated to be proapoptotic to cancer cells at high concentrations (> or = 1 microM). Data generated in the present study show that narciclasine displays potent antitumor effects in apoptosis-resistant as well as in apoptosis-sensitive cancer cells by impairing the organization of the actin cytoskeleton in cancer cells at concentrations that are not cytotoxic (IC(50) values of 30-90 nM). The current study further revealed that any chemical modification to the narciclasine backbone generally led to compounds of variable stability, weaker activity, or even the complete loss of antiproliferative effects in vitro.

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Purpose: The aims of the present work were to investigate the in vitro and in vivo antiangiogenic effects of chronic temozolomide treatment on various glioma models and to demonstrate whether bevacizumab (Avastin) increased the therapeutic benefits contributed by temozolomide in glioma.

Experimental Design: The expression levels of various antiangiogenic factors in four glioma cell lines were evaluated after chronic in vitro treatment with temozolomide by Western blot. Proliferation and migration assays were performed on human endothelial cells incubated with supernatants of glioma cells treated with and without temozolomide.

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Several naphthalimides have been evaluated clinically as potential anticancer agents. UNBS3157, a naphthalimide that belongs to the same class as amonafide, was designed to avoid the specific activating metabolism that induces amonafide's hematotoxicity. The current study shows that UNBS3157 rapidly and irreversibly hydrolyzes to UNBS5162 without generating amonafide.

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Myofibrillar protein loss occurring in catabolic situations is considered to be mediated by the release of proinflammatory cytokines and associated with a decrease in circulating and muscle levels of insulin-like growth factor I (IGF-I). In this paper, we investigated whether the C(2)C(12) myotube atrophy caused in vitro by TNF-alpha/IFN-gamma cytokines might be reversed by exogenous IGF-I. Our results showed that, despite the presence of TNF-alpha/IFN-gamma, IGF-I retained its full ability to induce the phosphorylation of Akt, Foxo3a, and GSK-3beta (respectively, 16-fold, 9-fold, and 2-fold) together with a decrease in atrogin-1 mRNA (-39%, P < 0.

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Purpose: We hypothesized that creatine supplementation would facilitate muscle anabolism by increasing the expression of growth factors and the phosphorylation of anabolic signaling molecules; we therefore tested the responses of mRNA for IGF-I and IGF-II and the phosphorylation state of components of anabolic signaling pathways p70(s6k) and 4E-BP1 to a bout of high-intensity resistance exercise after 5 d of creatine supplementation.

Methods: In a double-blind cross-over design, muscle biopsies were taken from the m. vastus lateralis at rest and 3 and 24 h postexercise in subjects who had taken creatine or placebo for 5 d (21 g x d(-1)).

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In catabolic conditions, atrogin-1/MAFbx, a muscle-specific ubiquitin-ligase required for muscle atrophy, is increased, and concentrations of IGF-I, a growth factor known to have antiproteolytic action, are reduced. To define the relationship between the decline in IGF-I and the induction of atrogin-1/MAFbx, we studied the effect of IGF-I replacement on atrogin-1/MAFbx mRNA in rats fasted for 51 h and in rats made diabetic with streptozotocin (STZ). Fasting produced a 5.

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Addition of creatine to the differentiation medium of C(2)C(12) cells leads to hypertrophy of the myotubes. To investigate the implication of insulin-like growth factor I (IGF-I) and myogenic regulatory factors (MRFs) in this hypertrophy, their mRNA levels were assessed during the first 72 h of differentiation. Creatine significantly increased the IGF-I mRNA level over the whole investigated period of time, whereas the MRF mRNA levels were only augmented at precise moments, suggesting a general activation mechanism for IGF-I and a specifically regulated mechanism for MRF transcription.

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MafBx and Murf are two new rat E3 ubiquitin ligases induced in muscle atrophy. Our goal was to investigate whether lipopolysaccharide (LPS) injection, a model of muscle catabolism, is associated with increased expression of MafBx and Murf. LPS (750 microg/100 g body weight) induces MafBx and Murf mRNA (respectively, 23-fold and 33-fold after 12 h; P<0.

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