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1.
Bull Cancer ; 108(9): 798-805, 2021 Sep.
Article de Anglais | MEDLINE | ID: mdl-34140154

RÉSUMÉ

INTRODUCTION: Apoptosis deregulation have been associated to tumorigenesis process and was highlighted as a prominent hallmark of cancer. Several mutations have been reported in several forms of Blood cancer. However, it has never been investigated in familial aggregations of hematological malignancies. METHODS: In this study, we performed a mutational analysis by sequencing the entire coding regions in four key apoptotic genes FAS, FASLG, CASP8 and CASP10 in 92 independent families belonging to French and Tunisian populations and diagnosed with several forms of familial hematological malignancies. RESULTS: We report 15 genetic variations among which 7 were previously reported in several form of cancers and have a potential effect on gene expression. Particularly, the CASP8 variants p.Asp302His and p.Lys337Lys were detected in 15% and 10% of our group of patients respectively and were previously reported in association to breast cancer and to breast cancer susceptibility. DISCUSSION: In this study, we do not report the underlining deleterious mutations in familial hematological malignancies, but we describe some variants with potential risk of developing blood cancer. To gain further insights on the association between apoptosis pathway deregulation and familial hematological malignancies, more apoptotic genes should be investigated.


Sujet(s)
Apoptose/génétique , Caspase 10/génétique , Caspase 8/génétique , Ligand de Fas/génétique , Tumeurs hématologiques/génétique , Antigènes CD95/génétique , Allèles , Études transversales , Analyse de mutations d'ADN/méthodes , Famille , France , Prédisposition génétique à une maladie , Humains , Introns , Mutation faux-sens , Perforine/génétique , Tunisie
2.
Invest Ophthalmol Vis Sci ; 60(6): 1943-1952, 2019 05 01.
Article de Anglais | MEDLINE | ID: mdl-31050722

RÉSUMÉ

Purpose: Ocular angiogenesis, including retinopathy of prematurity, diabetic retinopathy, and exudative age-related macular degeneration, are closely related to oxidative stress. Many reports have shown that the cellular protective mechanism against oxidative stress and inflammatory response has nuclear factor-erythroid 2-related factor-2 (Nrf2) activity. The aim of this study was to investigate the effectiveness and mechanism of Nrf2 activation in treating the ocular diseases with abnormal vessels. Methods: The effects of Nrf2 activators, bardoxolone methyl (BARD) and RS9, were evaluated against vascular endothelial growth factor (VEGF)-induced cell migration in human retinal microvascular endothelial cells (HRMECs). We measured the expression of the Nrf2 target genes, Ho-1 and Nqo-1 mRNA, in mouse retinas after a single injection of BARD and RS9. The effects and mechanisms of RS9 against retinal angiogenesis were evaluated using an oxygen-induced retinopathy (OIR) model in mice. Moreover, the effect of RS9 against choroidal neovascularization (CNV) was evaluated in a laser-induced CNV monkey model. Results: Both BARD and RS9 decreased VEGF-induced cell migration, and significantly increased Ho-1 mRNA expression; however, only RS9 significantly increased Nqo-1 mRNA. RS9 decreased retinal neovascularization through suppressing VEGF expression and increasing Nrf2, HO-1, platelet-derived growth factor receptor (PDGFR)-ß, and tight junction proteins in OIR murine retinas. Furthermore, RS9 showed a tendency toward decreasing CNV lesions, and improved vascular leakage in a CNV monkey model. Conclusions: These data indicate that a Nrf2 activator might be a candidate for treatment of ocular diseases characterized by pathophysiological angiogenesis and hyperpermeability.


Sujet(s)
Néovascularisation choroïdienne/traitement médicamenteux , Facteur-2 apparenté à NF-E2/métabolisme , Acide oléanolique/analogues et dérivés , Néovascularisation rétinienne/traitement médicamenteux , Vaisseaux rétiniens/métabolisme , Triterpènes/pharmacologie , Animaux , Perméabilité des membranes cellulaires/effets des médicaments et des substances chimiques , Mouvement cellulaire/effets des médicaments et des substances chimiques , Prolifération cellulaire/effets des médicaments et des substances chimiques , Cellules cultivées , Néovascularisation choroïdienne/métabolisme , Néovascularisation choroïdienne/anatomopathologie , Modèles animaux de maladie humaine , Cellules endothéliales/effets des médicaments et des substances chimiques , Cellules endothéliales/métabolisme , Cellules endothéliales/anatomopathologie , Angiographie fluorescéinique , Fond de l'oeil , Humains , Immunotransfert , Macaca fascicularis , Mâle , Souris , Souris de lignée C57BL , Facteur-2 apparenté à NF-E2/effets des médicaments et des substances chimiques , Acide oléanolique/pharmacologie , Néovascularisation rétinienne/métabolisme , Néovascularisation rétinienne/anatomopathologie , Vaisseaux rétiniens/anatomopathologie , Tomographie par cohérence optique
3.
Exp Eye Res ; 162: 110-115, 2017 09.
Article de Anglais | MEDLINE | ID: mdl-28739100

RÉSUMÉ

A shift or displacement of the retinal blood vessels (RBVs) with neuroretinal rim thinning indicates the progression of glaucomatous optic neuropathy. In chronic open angle glaucoma, individuals with RBV positional shifts exhibit more rapid visual field loss than those without RBV shifts. The retinal vessels reportedly move onto the optic nerve head (ONH) in response to glaucoma damage, suggesting that RBVs are pulled toward the ONH in response to increased cupping. Whether this phenomenon only applies to RVBs located in the vicinity or inside the ONH or, more generally, to RBVs also located far from the ONH, however, is unclear. The aim of this study was to evaluate the movement of RBVs located relatively far from the ONH edge after increasing intraocular pressure (IOP) in an experimental monkey model of glaucoma. Fundus photographs were obtained in 17 monkeys. High IOP was induced in the monkeys by laser photocoagulation burns applied uniformly with 360° irradiation around the trabecular meshwork of the left eye. The right eye was left intact and used as a non-treated control. Considering the circadian rhythm of IOP, it was measured in both eyes of each animal at around the same time-points. Then, fundus photographs were obtained. Using Image J image analysis software, an examiner (N.E.) measured the fundus photographs at two time-points, i.e. before laser treatment (time 1) and the last fundus photography after IOP elevation (time 2). The following parameters were measured (in pixels): 1) vertical diameter of the ONH (DD), 2) distance from the ONH edge to the first bifurcation point of the superior branch of the central retinal vein (UV), 3) distance from the ONH edge to the first bifurcation point of the inferior branch of the central retinal vein (LV), 4) ONH area, and 5) surface area of the cup of the ONH. We calculated the ratios of UV to DD (UV/DD), LV to DD (LV/DD), and the cup area to disc area ratio (C/D). The mean UV/DD at time 1 (0.656 ± 0.233) was decreased at time 2 (0.542 ± 0.192) (p < 0.01), and the mean LV/DD at time 1 (0.642 ± 0.151) was decreased at time 2 (0.534 ± 0.171) (p < 0.01). The mean C/D at time 1 (0.303 ± 0.035) was increased at time 2 (0.556 ± 0.110) (p < 0.01). The mean IOP at time 1 was 19.8 ± 2.5 and that at time 2 was 54.2 ± 15.8. The amount and rate of the change in LV/DD and C/D between time 1 and time 2 were significantly correlated (r = -0.654 and -0.536, p = 0.004 and 0.026, respectively). Therefore, in an experimental monkey model of glaucoma, RBVs located relatively far from the ONH were pulled toward the ONH as cupping increased.


Sujet(s)
Glaucome/physiopathologie , Pression intraoculaire/physiologie , Papille optique/vascularisation , Vaisseaux rétiniens/physiopathologie , Animaux , Modèles animaux de maladie humaine , Glaucome/diagnostic , Glaucome/étiologie , Haplorhini , Mâle , Vaisseaux rétiniens/imagerie diagnostique
4.
Ophthalmic Res ; 58(2): 99-106, 2017.
Article de Anglais | MEDLINE | ID: mdl-28564657

RÉSUMÉ

AIMS: We investigated the relationship between elevated intraocular pressure (IOP) and changes in global and peripapillary sector retinal nerve fiber layer (RNFL) thickness around the optic nerve head (ONH) in the laser-induced ocular hypertension monkey model. METHODS: To induce high IOP, green laser photocoagulation burns were applied around the trabecular meshwork of 1 eye from each of 12 cynomolgus monkeys. The animals had been acclimated to IOP measurement under conscious conditions for more than 2 months, and IOP was chronologically measured. RNFL thickness was measured for 6 peripapillary sectors and global area using spectral-domain optical coherence tomography. RESULTS: After model induction, marked IOP elevation and enlarged optic disk cupping were observed. Thinning of the RNFL associated with elevated IOP was observed around the ONH from 6 until 9 weeks after laser treatment, and the degree of reduction in RNFL thickness varied between the peripapillary sectors. Correlations between cumulative IOP elevation and RNFL thickness reduction were statistically significant for the temporal-superior (p = 0.024), nasal-inferior (p = 0.044), and temporal (p = 0.049) sectors, and global RNFL (p = 0.018). CONCLUSIONS: These results suggest that this model reflected the pathology of clinical glaucoma in terms of the specific pattern of RNFL thinning around the ONH.


Sujet(s)
Pression intraoculaire/physiologie , Neurofibres/anatomopathologie , Hypertension oculaire/physiopathologie , Papille optique/anatomopathologie , Cellules ganglionnaires rétiniennes/anatomopathologie , Tomographie par cohérence optique/méthodes , Animaux , Modèles animaux de maladie humaine , Lasers/effets indésirables , Macaca fascicularis , Mâle , Hypertension oculaire/diagnostic
5.
AAPS PharmSciTech ; 18(6): 2368-2377, 2017 Aug.
Article de Anglais | MEDLINE | ID: mdl-28127720

RÉSUMÉ

The closed-die compaction behaviour of D-mannitol granules has been simulated by the discrete element method (DEM) to investigate the granule rearrangement and fracture behaviour during compaction which affects the compactibility of the tablet. The D-mannitol granules produced in a fluidized bed were modelled as agglomerates of primary particles connected by linear spring bonds. The validity of the model granule used in the DEM simulation was demonstrated by comparing to the experimental results of a uniaxial compression test. During uniaxial compression, the numerical results of the force-displacement curve corresponded reasonably well to the experimental data. The closed-die compaction of the modelled granules was carried out to investigate the rearrangement and fracture behaviours of the granule at different upper platen velocities. The forces during closed-die compaction calculated by DEM fluctuated in the low-pressure region due to the rearrangement of granules. A Heckel analysis showed that the force fluctuation occurred at the initial bending region of the Heckel plot, which represents the granule rearrangement and fracture. Furthermore, the upper platen velocity affected the trend of compaction forces, which can lead to compaction failure due to capping. These results could contribute to designing the appropriate granules during closed-die compaction.


Sujet(s)
Comprimés , Technologie pharmaceutique , Mannitol/composition chimique , Pression , Comprimés/composition chimique
6.
Fam Cancer ; 15(4): 497-506, 2016 10.
Article de Anglais | MEDLINE | ID: mdl-26833043

RÉSUMÉ

Ovarian neoplasms secondary to germline BRCA mutations had been described to have a more favourable survival. There is only few data concerning the prognosis of non mutated patients presenting clinical features evocative of BRCA alterations. We retrospectively collected data from patients treated in our institution for an invasive ovarian carcinoma between 1995 and 2011. Patients considered at high risk of BRCA mutation were tested for BRCA1/2 germline mutations. We described clinical, pathological and therapeutic features and compared prognosis of BRCA mutation carriers and non-mutated patients. Out of 617 ovarian cancer patients, we identified 104 patients who were considered at high risk of mutation. The 33 mutated patients were more likely to present a personal (33 vs. 10 %, p = 0.003) or a family (42 vs. 24 %, p = 0.06) history of breast/ovarian cancers. BRCA1/2 mutation carriers and wild type patients displayed similar prognosis: median progression-free survival (PFS) of 20.9 versus 37.7 months (p = 0.21); median overall survival (OS) of 151.2 versus 122.5 months (p = 0.52). Personal history of breast cancer increased both PFS [HR = 0.45 (95CI 0.25-0.81)] and OS [HR = 0.35 (95CI 0.16-0.75)]. In multivariate analysis, this parameter was an independent prognostic feature, whereas the identification of a BRCA1/2 mutation was not. In our cohort, all patients at high risk of BRCA mutation share a similar prognosis, whatever is their germline mutation status. Prognosis seems to be more influenced by clinical history than by germline mutations identification. If it is confirmed in larger and independent series, this result suggests that the hypothesis of other BRCA pathway alterations (BRCAness phenotype) deserves to be deeply explored.


Sujet(s)
Protéine BRCA1/génétique , Protéine BRCA2/génétique , Mutation , Tumeurs de l'ovaire/génétique , Tumeurs de l'ovaire/mortalité , Adulte , Tumeurs du sein/génétique , Survie sans rechute , Femelle , Mutation germinale , Humains , Adulte d'âge moyen , Tumeurs de l'ovaire/anatomopathologie , Tumeurs de l'ovaire/thérapie , Pronostic
7.
PLoS One ; 9(8): e104302, 2014.
Article de Anglais | MEDLINE | ID: mdl-25144364

RÉSUMÉ

BACKGROUND: Breast cancer stem cells (BCSCs) have been recognized as playing a major role in various aspects of breast cancer biology. To identify specific biomarkers of BCSCs, we have performed comparative proteomics of BCSC-enriched and mature cancer cell populations from the human breast cancer cell line (BCL), BrCA-MZ-01. METHODS: ALDEFLUOR assay was used to sort BCSC-enriched (ALDH+) and mature cancer (ALDH-) cell populations. Total proteins were extracted from both fractions and subjected to 2-Dimensional Difference In-Gel Electrophoresis (2-D DIGE). Differentially-expressed spots were excised and proteins were gel-extracted, digested and identified using MALDI-TOF MS. RESULTS: 2-D DIGE identified poly(ADP-ribose) polymerase 1 (PARP1) as overexpressed in ALDH+ cells from BrCA-MZ-01. This observation was confirmed by western blot and extended to four additional human BCLs. ALDH+ cells from BRCA1-mutated HCC1937, which had the highest level of PARP1 overexpression, displayed resistance to olaparib, a specific PARP1 inhibitor. CONCLUSION: An unbiased proteomic approach identified PARP1 as upregulated in ALDH+, BCSC-enriched cells from various human BCLs, which may contribute to clinical resistance to PARP inhibitors.


Sujet(s)
Antinéoplasiques/pharmacologie , Tumeurs du sein/enzymologie , Cellules souches tumorales/enzymologie , Phtalazines/pharmacologie , Pipérazines/pharmacologie , Poly(ADP-ribose) polymerases/métabolisme , Lignée cellulaire tumorale , Survie cellulaire/effets des médicaments et des substances chimiques , Électrophorèse bidimensionnelle sur gel , Régulation de l'expression des gènes tumoraux/effets des médicaments et des substances chimiques , Humains , Inhibiteurs de poly(ADP-ribose) polymérases , Spectrométrie de masse MALDI
8.
Genet Test Mol Biomarkers ; 18(5): 299-305, 2014 May.
Article de Anglais | MEDLINE | ID: mdl-24620857

RÉSUMÉ

Sanger DNA sequencing is a robust and flexible technology and should have a crucial role in clinical practice for a long time. Nevertheless, in routine application of DNA sequencing, we are regularly confronted with sequence data quality problems. Surprisingly, we found that the definition of sequence quality is fuzzy and too empirical for many clinical applications. There are few studies or guidelines that directly address quality issues for Sanger sequencing in clinical situations. In addition, these use several combined parameters to ensure the sequence quality; this is too complicated to apply for daily use. Our heuristic analysis of nearly 46,000 sequence traces demonstrated that a combination of three basic parameters (average quality value, average sequence intensity, and electropherogram profile) was necessary and sufficient to determine accurately the quality of any sequence, even when deletions, insertions, and/or repeat sequence regions were present in a sequence trace. Therefore, we propose a simple and practical method with a diagram and decision making table for sequence quality determination in clinical sequencing.


Sujet(s)
Analyse de séquence d'ADN/normes , Recommandations comme sujet , Humains , Réaction de polymérisation en chaîne
9.
Gen Physiol Biophys ; 33(2): 145-55, 2014.
Article de Anglais | MEDLINE | ID: mdl-24448372

RÉSUMÉ

Human plasma contains wide variety of bioactive proteins that have proved essential in therapeutic discovery. However many human plasma proteins remain orphans with unknown biological functions. Evidences suggest that some plasma components target the respiratory system. In the present study we adapted heparin affinity chromatography to fractionate human plasma for functional bioassay. Fractions from pooled human plasma yielded particular plasma fractions with strong cough suppressing effects. Purification yielded a fraction that was finally identified as an activated blood coagulation factor fXIa using liquid chromatography-tandem mass spectrometry (LC-MS/MS) and matrix-assisted laser desorption ionization/time-of-flight mass spectrometry (MALDI/TOF-MS). The fraction almost completely suppressed coughs induced by either chemical or mechanical stimulation applied to larynx or bifurcation of guinea-pig trachea. Cough suppressing effect of the fraction and commercially available fXIa were one million times stronger than codeine and codeine only partially suppressed the mechanically triggered coughing in animal model. Recent reviews highlighted prominent shortcomings of current available antitussives, including narcotic opioids such as codeine and their unpleasant or intolerable side effects. Therefore, safer and more effective cough suppressants would be welcome, and present findings indicate that fXIa in human plasma as a very promising, new therapeutic candidate for effective antitussive action.


Sujet(s)
Antitussifs/sang , Antitussifs/pharmacologie , Toux/traitement médicamenteux , Animaux , Antitussifs/isolement et purification , Antitussifs/métabolisme , Dosage biologique , Analyse chimique du sang , Capsaïcine/pharmacologie , Chromatographie d'affinité , Codéine/pharmacologie , Toux/induit chimiquement , Découverte de médicament , Facteur XIa/isolement et purification , Facteur XIa/métabolisme , Facteur XIa/pharmacologie , Cochons d'Inde , Héparine/métabolisme , Mâle , Phénomènes mécaniques
10.
Inflamm Bowel Dis ; 19(11): 2315-25, 2013 Oct.
Article de Anglais | MEDLINE | ID: mdl-23949622

RÉSUMÉ

BACKGROUND: Vanin-1 is an epithelial pantetheinase, which regulates intestinal inflammation in mouse. We investigated whether human VNN1 levels could be associated to the susceptibility to inflammatory bowel diseases (IBD) and explored the participation of PPARg to these processes. METHODS: We studied VNN1 expression in colon biopsies from IBD patients. We investigated polymorphisms in the regulatory regions of the VNN1 gene and examined their genetic association with the disease. Functional relevance of these single-nucleotide polymorphisms (SNPs) was assayed, and we tested PPARg in nuclear complexes associated with specific VNN1 polymorphic sequences. In mouse, we examined Vanin-1 expression in gut and feces during dextran sulfate sodium-induced colitis and assayed the effect of PPARg on Vanin-1 regulation. RESULTS: VNN1 is expressed by enterocytes and is upregulated in IBD. Three SNPs are statistically associated to IBD. The regions containing these SNPs specifically bind nuclear complexes and are correlated with the VNN1 transcript abundance in colon in an allele-dependent manner. One rare SNP is associated to severe ulcerative colitis with strong VNN1 and dropped PPARg levels. PPARg is involved in nuclear complexes that bound to VNN1 regulatory sites. Similarly, Vanin-1 is tightly regulated in the mouse gut in normal and colitis conditions and PPARg regulates its expression. CONCLUSIONS: VNN1 is a marker for IBD. Polymorphic positions in the VNN1 locus are direct targets for nuclear factors that might regulate the level of VNN1 in colon, and this could be linked to IBD susceptibility. It is hoped that modulating locally VNN1 expression or activity can be exploited to develop future therapeutic strategies against IBD.


Sujet(s)
Amidohydrolases/génétique , Prédisposition aux maladies , Maladies inflammatoires intestinales/génétique , Polymorphisme de nucléotide simple/génétique , Séquences d'acides nucléiques régulatrices/génétique , Amidohydrolases/métabolisme , Animaux , Technique de Western , Études cas-témoins , Test de retard de migration électrophorétique , Technique d'immunofluorescence , Protéines liées au GPI/génétique , Protéines liées au GPI/métabolisme , Tube digestif/métabolisme , Tube digestif/anatomopathologie , Humains , Techniques immunoenzymatiques , Maladies inflammatoires intestinales/anatomopathologie , Souris , ARN messager/génétique , Réaction de polymérisation en chaine en temps réel , RT-PCR , Analyse sur puce à tissus
11.
Pathobiology ; 80(5): 219-27, 2013.
Article de Anglais | MEDLINE | ID: mdl-23614934

RÉSUMÉ

Family structure, lack of reliable information, cost, and delay are usual concerns when deciding to perform BRCA analyses. Testing breast cancer tissues with four antibodies (MS110, lys27H3, vimentin, and KI67) in addition to grade evaluation enabled us to rapidly select patients for genetic testing identification. We constituted an initial breast cancer tissue microarray, considered as a learning set, comprising 27 BRCA1 and 81 sporadic tumors. A second independent validation set of 28 BRCA1 tumors was matched to 28 sporadic tumors using the same original conditions. We investigated morphological parameters and 21 markers by immunohistochemistry. A logistic regression model was used to select the minimal number of markers providing the best model to predict BRCA1 status. The model was applied to the validation set to estimate specificity and sensibility. In the initial set, univariate analyses identified 11 markers significantly associated with BRCA1 status. Then, the best multivariate model comprised only grade 3, MS110, Lys27H3, vimentin, and KI67. When applied to the validation set, BRCA1 tumors were correctly classified with a sensitivity of 83% and a specificity of 81%. The performance of this model was superior when compared to other profiles. This study offers a new rapid and cost-effective method for the prescreening of patients at high risk of being BRCA1 mutation carriers, to guide genetic testing, and finally to provide appropriate preventive measures, advice, and treatments including targeted therapy to patients and their families.


Sujet(s)
Protéine BRCA1/génétique , Tumeurs du sein/diagnostic , Mutation germinale , Histone/analyse , Antigène KI-67/analyse , Vimentine/analyse , Protéine BRCA1/analyse , Tumeurs du sein/composition chimique , Tumeurs du sein/génétique , Tumeurs du sein/anatomopathologie , Analyse de mutations d'ADN , Femelle , Prédisposition génétique à une maladie , Dépistage génétique , Humains , Immunohistochimie , Modèles logistiques , Lysine , Analyse multifactorielle , Grading des tumeurs , Sélection de patients , Phénotype , Valeur prédictive des tests , Pronostic , Reproductibilité des résultats , Analyse sur puce à tissus
12.
Brain Res ; 1513: 135-42, 2013 Jun 04.
Article de Anglais | MEDLINE | ID: mdl-23548603

RÉSUMÉ

We previously reported that tipepidine, a centrally acting non-narcotic antitussive, has an antidepressant-like effect in normal and imipramine treatment-resistant depression model rats. Recently, mapping the induction of c-fos-like immunoreactivity (FLI) in the rat brain showed FLI-positive neurons in several brain areas after acute administration of different classes of antidepressants. Here, the effect of a single injection of an antidepressive dose of tipepidine on FLI was studied in seven areas of the rat brain including the central nucleus of the amygdala (CeA) and the nucleus accumbens (NAc). Desipramine was also used for comparison. Rats were anesthetized and perfused 2h after injection with tipepidine (20 and 40mg/kg, i.p.), desipramine (10mg/kg, i.p.), or saline. Then, immunostaining of FLI-positive neurons in brain slices was performed with conventional methods. A single injection of tipepidine increased FLI-positive neurons in the CeA, similar to preexisting antidepressants, and induced the characteristic pattern of an increase in FLI-positive neurons in six other brain areas including the NAc, an effect that was different from other antidepressants. In addition, a single injection of desipramine (10mg/kg) or tipepidine (20mg/kg) decreased the immobility time in the forced swimming test to a similar extent. The results obtained from the previous behavioral study and the current immunohistochemical study suggest that tipepidine may be a novel antidepressant.


Sujet(s)
Antidépresseurs/pharmacologie , Encéphale/effets des médicaments et des substances chimiques , Encéphale/métabolisme , Régulation de l'expression des gènes/effets des médicaments et des substances chimiques , Pipéridines/pharmacologie , Protéines proto-oncogènes c-fos/métabolisme , Animaux , Encéphale/anatomie et histologie , Désipramine/pharmacologie , Relation dose-effet des médicaments , Mâle , Rats , Rat Wistar , Natation
13.
BMC Neurol ; 11: 9, 2011 Jan 24.
Article de Anglais | MEDLINE | ID: mdl-21255467

RÉSUMÉ

BACKGROUND: Schwannomatosis is a disease characterized by multiple non-vestibular schwannomas. Although biallelic NF2 mutations are found in schwannomas, no germ line event is detected in schwannomatosis patients. In contrast, germline mutations of the SMARCB1 (INI1) tumor suppressor gene were described in familial and sporadic schwannomatosis patients. METHODS: To delineate the SMARCB1 gene contribution, the nine coding exons were sequenced in a series of 56 patients affected with a variable number of non-vestibular schwannomas. RESULTS: Nine variants scattered along the sequence of SMARCB1 were identified. Five of them were classified as deleterious. All five patients carrying a SMARCB1 mutation had more multiple schwannomas, corresponding to 10.2% of patients with schwannomatosis. They were also diagnosed before 35 years of age. CONCLUSIONS: These results suggest that patients with schwannomas have a significant probability of carrying a SMARCB1 mutation. Combined with data available from other studies, they confirm the clinical indications for genetic screening of the SMARCB1 gene.


Sujet(s)
Protéines chromosomiques nonhistones/génétique , Protéines de liaison à l'ADN/génétique , Mutation germinale/génétique , Facteurs de transcription/génétique , Adolescent , Adulte , Sujet âgé , Enfant , Enfant d'âge préscolaire , Exons/génétique , Femelle , Prédisposition génétique à une maladie , Humains , Mâle , Adulte d'âge moyen , Neurinome/génétique , Neurofibromatoses/génétique , Protéine SMARCB1 , Analyse de séquence d'ADN/méthodes , Tumeurs cutanées/génétique
14.
J Med Genet ; 47(10): 721-2, 2010 Oct.
Article de Anglais | MEDLINE | ID: mdl-20685668

RÉSUMÉ

Heterozygous APC germline alteration is responsible for familial adenomatous polyposis, a colon cancer predisposition with almost complete penetrance. Point mutations generally lead to truncated proteins or no protein at all. They mainly involve exon 3 to codon 1700 (exon 15). The work presented here delineates precisely the APC mutation spectrum from 15 years of systematic molecular screening which identified 863 independent alterations in the French population.


Sujet(s)
Protéine de la polypose adénomateuse colique/génétique , Polypose adénomateuse colique/génétique , Analyse de mutations d'ADN/méthodes , Mutation germinale , Hybridation génomique comparative , France , Gènes APC , Prédisposition génétique à une maladie , Dépistage génétique , Humains , Séquençage par oligonucléotides en batterie , Mutation ponctuelle , Analyse de séquence d'ADN
15.
Genes Chromosomes Cancer ; 49(6): 560-8, 2010 Jun.
Article de Anglais | MEDLINE | ID: mdl-20232483

RÉSUMÉ

Desmoid tumors are fibroblastic/myofibroblastic proliferations. Previous studies reported that CTNNB1 mutations were detected in 84% and that mutations of the APC gene were found in several cases of sporadic desmoid tumors lacking CTNNB1 mutations. Forty tumors were analyzed by comparative genomic hybridization (CGH). Karyotype and fluorescence in situ hybridization revealed a nonrandom occurrence of trisomy 8 associated with an increased risk of recurrence. We report the first molecular characterization including a large series of patients. We performed array CGH on frozen samples of 194 tumors, and we screened for APC mutations in patients without CNNTB1 mutation. A high frequency of genomically normal tumors was observed. Four relevant and recurrent alterations (loss of 6q, loss of 5q, gain of 20q, and gain of Chromosome 8) were found in 40 out of 46 tumors with chromosomal changes. Gain of Chromosomes 8 and 20 was not associated with an increased risk of recurrence. Cases with loss of 5q had a minimal common region in 5q22.5 including the APC locus. Alterations of APC, including loss of the entire locus, and CTNNB1 mutation could explain the tumorigenesis in 89% of sporadic desmoids tumors and desmoids tumors occurring in the context of Gardner's syndrome. A better understanding of the pathogenetic pathways in the initiation and progression of desmoid tumors requires studies of 8q and 20q gains, as well as of 6q and 5q losses, and study of the Wnt/beta-catenin pathway.


Sujet(s)
Tumeurs de l'abdomen/génétique , Fibromatose agressive/génétique , Tumeurs de l'abdomen/diagnostic , Tumeurs de l'abdomen/anatomopathologie , Adolescent , Adulte , Sujet âgé , Sujet âgé de 80 ans ou plus , Loi du khi-deux , Enfant , Enfant d'âge préscolaire , Hybridation génomique comparative/méthodes , Femelle , Fibromatose agressive/diagnostic , Fibromatose agressive/anatomopathologie , Humains , Hybridation fluorescente in situ , Nourrisson , Nouveau-né , Estimation de Kaplan-Meier , Caryotypage , Mâle , Adulte d'âge moyen , Séquençage par oligonucléotides en batterie/méthodes , Réaction de polymérisation en chaîne , Grossesse , Analyse de séquence d'ADN/méthodes , bêta-Caténine/génétique
16.
Hum Mutat ; 30(6): 867-75, 2009 Jun.
Article de Anglais | MEDLINE | ID: mdl-19224586

RÉSUMÉ

Several techniques have been developed to screen mismatch repair (MMR) genes for deleterious mutations. Until now, two different techniques were required to screen for both point mutations and large rearrangements. For the first time, we propose a new approach, called "quantitative PCR (qPCR) high-resolution melting (HRM) curve analysis (qPCR-HRM)," which combines qPCR and HRM to obtain a rapid and cost-effective method suitable for testing a large series of samples. We designed PCR amplicons to scan the MLH1 gene using qPCR HRM. Seventy-six patients were fully scanned in replicate, including 14 wild-type patients and 62 patients with known mutations (57 point mutations and five rearrangements). To validate the detected mutations, we used sequencing and/or hybridization on a dedicated MLH1 array-comparative genomic hybridization (array-CGH). All point mutations and rearrangements detected by denaturing high-performance liquid chromatography (dHPLC)+multiplex ligation-dependent probe amplification (MLPA) were successfully detected by qPCR HRM. Three large rearrangements were characterized with the dedicated MLH1 array-CGH. One variant was detected with qPCR HRM in a wild-type patient and was located within the reverse primer. One variant was not detected with qPCR HRM or with dHPLC due to its proximity to a T-stretch. With qPCR HRM, prescreening for point mutations and large rearrangements are performed in one tube and in one step with a single machine, without the need for any automated sequencer in the prescreening process. In replicate, its reagent cost, sensitivity, and specificity are comparable to those of dHPLC+MLPA techniques. However, qPCR HRM outperformed the other techniques in terms of its rapidity and amount of data provided.


Sujet(s)
Protéines adaptatrices de la transduction du signal/génétique , Tumeurs colorectales héréditaires sans polypose/génétique , Analyse de mutations d'ADN/méthodes , Mutation germinale/génétique , Protéines nucléaires/génétique , Dénaturation d'acide nucléique , Mutation ponctuelle/génétique , Réaction de polymérisation en chaîne/méthodes , Amorces ADN/métabolisme , Exons/génétique , Réarrangement des gènes , Humains , Protéine-1 homologue de MutL , Hybridation d'acides nucléiques , Normes de référence
17.
Oncol Rep ; 16(1): 97-101, 2006 Jul.
Article de Anglais | MEDLINE | ID: mdl-16786129

RÉSUMÉ

Gastrointestinal stromal tumours (GISTs) are the most common mesenchymal tumours of the gastrointestinal tract. Most of them have an activating mutation of KIT or PDGFRalpha tyrosine-kinase receptors. Imatinib is a selective tyrosine-kinase inhibitor of ABL, KIT and PDGFR, and provides a clinical benefit in about 85% of patients with advanced GIST. Unfortunately, secondary resistance following initial responses occurs in most of the cases, and molecular mechanisms are poorly understood. We sequenced KIT and PGDFRalpha exons from one patient with GIST before and after the development of imatinib resistance. We identified, in addition to a primary mutation in exon 9, a secondary mutation in KIT exon 13 (first kinase domain) in the resistant sample. We demonstrate for the first time the feasibility of sequencing such samples removed by non-surgical biopsies during imatinib therapy. Such a approach, far less invasive than surgery and combined with sequencing, will likely help in better tailoring the treatment of advanced GISTs and understanding the mechanisms of resistance and response to imatinib.


Sujet(s)
Antinéoplasiques/pharmacologie , Résistance aux médicaments antinéoplasiques , Tumeurs gastro-intestinales/génétique , Mutation , Pipérazines/pharmacologie , Protéines proto-oncogènes c-kit/génétique , Pyrimidines/pharmacologie , Benzamides , Biopsie , Exons , Femelle , Humains , Mésilate d'imatinib , Adulte d'âge moyen , Récepteur au PDGF bêta/génétique , Analyse de séquence d'ADN , Cellules stromales/métabolisme
19.
Int J Oncol ; 21(5): 989-96, 2002 Nov.
Article de Anglais | MEDLINE | ID: mdl-12370745

RÉSUMÉ

Alterations of chromosomal region 8p11-21 are very frequent in human cancers, and especially in breast cancer; yet, most of the genes involved have not been identified. We performed laser capture microdissection in a series of 52 consecutive breast tumor samples to obtain pure tumor cells without surrounding normal breast. To determine genomic subregions in which some of the cancer genes may be located, we conducted a search for loss of heterozygosity (LOH) at 13 microsatellite markers from this region. Two-thirds of the tumors showed LOH at least at one marker. Microdissection of pure tumor samples was helpful to precisely define four LOH subregions. No LOH was observed in the corresponding peritumoral tissues. We studied by immunohistochemistry (IHC) on tissue-microarrays the expression in the same tumors, of the protein product of three potential tumor genes lying close to or within the subregions of LOH. In most samples, the TACC1 gene product was downregulated in tumor cells as compared to normal cells. Our results show that the centromeric portion of chromosome arm 8p is frequently altered in breast tumor cells.


Sujet(s)
Tumeurs du sein/génétique , Chromosomes humains de la paire 8 , Perte d'hétérozygotie , Répétitions microsatellites , Tumeurs du sein/composition chimique , Femelle , Protéines foetales/analyse , Marqueurs génétiques , Humains , Immunohistochimie , Protéines associées aux microtubules/analyse , Adulte d'âge moyen , Neuréguline-1/analyse , Protéines nucléaires/analyse
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