Your browser doesn't support javascript.
loading
Montrer: 20 | 50 | 100
Résultats 1 - 20 de 41
Filtrer
1.
J Neurooncol ; 2024 Jun 27.
Article de Anglais | MEDLINE | ID: mdl-38937309

RÉSUMÉ

PURPOSE: Diffuse midline gliomas (DMG) with H3K27 alterations (H3K27M-DMG) are a highly aggressive form of brain cancer. In rare cases, H3K27 mutations have been observed in diffuse non-midline gliomas (DNMG). It is currently unclear how these tumors should be classified. Herein, we analyze the characteristics of DNMG with H3K27M mutations. METHODS: We reviewed the clinical, radiological and histological characteristics of all patients with an H3K27M mutated diffuse glioma diagnosed in our institution, between 2016 and 2023, to identify cases with a non-midline location. We then performed a molecular characterization (DNA methylation profiling, whole genome and transcriptome sequencing or targeted sequencing) of patients with an H3K27M-mutant DNMG and reviewed previously reported cases. RESULTS: Among 51 patients (18 children and 33 adults) diagnosed with an H3K27M diffuse glioma, we identified two patients (4%) who had a non-midline location. Including our two patients, 39 patients were reported in the literature with an H3K27M-mutant DNMG. Tumors were most frequently located in the temporal lobe (48%), affected adolescents and adults, and were associated with a poor outcome (median overall survival was 10.3 months (0.1-84)). Median age at diagnosis was 19.1 years. Tumors frequently harbored TP53 mutations (74%), ATRX mutations (71%) and PDGFRA mutations or amplifications (44%). In DNA methylation analysis, H3K27M-mutant DNMG clustered within or close to the reference group of H3K27M-mutant DMG. Compared to their midline counterpart, non-midline gliomas with H3K27M mutations seemed more frequently associated with PDGFRA alterations. CONCLUSION: DNMG with H3K27M mutations share many similarities with their midline counterpart, suggesting that they correspond to a rare anatomical presentation of these tumors. This is of paramount importance, as they may benefit from new therapeutic approaches such as ONC201.

2.
Int J Mol Sci ; 24(21)2023 Oct 27.
Article de Anglais | MEDLINE | ID: mdl-37958668

RÉSUMÉ

Targeting EGFR alterations, particularly the L858R (Exon 21) mutation and Exon 19 deletion (del19), has significantly improved the survival of lung cancer patients. From now on, the issue is to shorten the time to treatment. Here, we challenge two well-known rapid strategies for EGFR testing: the cartridge-based platform Idylla™ (Biocartis) and a digital droplet PCR (ddPCR) approach (ID_Solution). To thoroughly investigate each testing performance, we selected a highly comprehensive cohort of 39 unique del19 (in comparison, the cbioportal contains 40 unique del19), and 9 samples bearing unique polymorphisms in exon 19. Additional L858R (N = 24), L861Q (N = 1), del19 (N = 63), and WT samples (N = 34) were used to determine clear technical and biological cutoffs. A total of 122 DNA samples extracted from formaldehyde-fixed samples was used as input. No false positive results were reported for either of the technologies, as long as careful droplet selection (ddPCR) was ensured for two polymorphisms. ddPCR demonstrated higher sensitivity in detecting unique del19 (92.3%, 36/39) compared to Idylla (67.7%, 21/31). However, considering the prevalence of del19 and L858R in the lung cancer population, the adjusted theranostic values were similar (96.51% and 95.26%, respectively). ddPCR performs better for small specimens and low tumoral content, but in other situations, Idylla is an alternative (especially if a molecular platform is absent).


Sujet(s)
Carcinome pulmonaire non à petites cellules , Tumeurs du poumon , Humains , Carcinome pulmonaire non à petites cellules/génétique , Récepteurs ErbB/génétique , Tumeurs du poumon/diagnostic , Tumeurs du poumon/génétique , Techniques de diagnostic moléculaire , Mutation , Réaction de polymérisation en chaîne/méthodes , Médecine de précision
3.
Am J Surg Pathol ; 47(1): 131-144, 2023 01 01.
Article de Anglais | MEDLINE | ID: mdl-36418240

RÉSUMÉ

Adult tumors diagnosed as cerebellar glioblastoma (cGBM) are rare and their optimal classification remains to be determined. The aim of this study was to identify subgroups of cGBM based on targeted molecular analysis. cGBM diagnosed between 2003 and 2017 were identified from the French Brain Tumor Database and reviewed according to the WHO 2021 classification. The following molecular alterations were studied: IDH1/2 , H3F3A , FGFR1 , BRAF , TERT promoter mutations, EGFR amplification, MGMT promoter methylation, and alternative lengthening of telomere status. DNA methylation profile was assessed in a subset of cases. Eighty-three cGBM were included and could be classified into 6 mutually exclusive subgroups associated with median age at diagnosis (MA) and prognosis: TERT -mutant and/or EGFR -amplified tumors (n=22, 26.5%, MA=62 y, median overall survival [OS]=4 mo), H3K27M-mutant tumors (n=15, 18.1%, MA=48 y, median OS=8 mo), mitogen-activated protein kinases (MAPK) pathway-activated tumors ( FGFR1 , BRAF mutation, or occurring in neurofibromatosis type I patients, n=15, 18.1%, MA=48 y, median OS=57 mo), radiation-associated tumors (n=5, 6%, MA=47 y, median OS=5 mo), IDH-mutant tumors (n=1), and unclassified tumors (n=25, 30.1%, MA=63 y, median OS=17 mo). Most MAPK pathway-activated tumors corresponded to high-grade astrocytomas with piloid features based on DNA methylation profiling. In multivariate analysis, MAPK pathway-activating alterations, ATRX loss of expression, and alternative lengthening of telomere positivity were independently associated with a better outcome and TERT / EGFR alterations with a worse outcome. cGBM display an important intertumoral heterogeneity. Targeted molecular analysis enables to classify the majority of tumors diagnosed as cGBM into mutually exclusive and clinically relevant subgroups. The presence of MAPK pathway alterations is associated with a much better prognosis.


Sujet(s)
Tumeurs du cerveau , Glioblastome , Tumeurs sous-tentorielles , Adulte , Humains , Tumeurs du cerveau/diagnostic , Tumeurs du cerveau/génétique , Tumeurs du cerveau/anatomopathologie , Récepteurs ErbB/génétique , Glioblastome/diagnostic , Glioblastome/génétique , Isocitrate dehydrogenases/génétique , Mutation , Pronostic , Protéines proto-oncogènes B-raf/génétique
4.
J Neurooncol ; 157(3): 511-521, 2022 May.
Article de Anglais | MEDLINE | ID: mdl-35364762

RÉSUMÉ

BACKGROUND: Molecular glioblastomas (i.e. without the histological but with the molecular characteristics of IDH-wild-type glioblastoma) frequently lack contrast enhancement, which can wrongly lead to suspect a lower-grade glioma. Herein, we aimed to assess the diagnostic value of gyriform infiltration as an imaging marker for molecular glioblastomas. METHODS: Two independent investigators reviewed the MRI scans from patients with newly diagnosed gliomas for the presence of a gyriform infiltration defined as an elective cortical hypersignal on MRI FLAIR sequence. Diagnostic test performance of this sign for the diagnosis of molecular glioblastoma were calculated. RESULTS: A total of 426 patients were included, corresponding to 31 molecular glioblastoma, 294 IDH-wild-type glioblastoma, 50 IDH-mutant astrocytoma, and 51 IDH-mutant 1p19q-codeleted oligodendroglioma. A gyriform infiltration was observed in 16/31 (52%) molecular glioblastoma, 40/294 (14%) IDH-wild-type glioblastoma, and none of the IDH-mutant glioma. All the 56 gyriform-infiltration-positive tumors were IDH-wild-type and all but two had a TERT promoter mutation. The inter-rater agreement was good (κ = 0.69, p < 0.001). The sensitivity, specificity, positive predictive value and negative predictive value of the presence of a gyriform infiltration for the diagnosis of molecular glioblastoma were 52%, 90%, 29%, 96%, respectively. The median overall survival was better for gyriform-infiltration-negative patients compared to gyriform-infiltration-positive patients in the whole series and in patients with non-enhancing lesions (n = 95) (25.6 vs 16.9 months, p = 0.005 and 20.2 months vs not reached, p < 0.001). CONCLUSION: Gyriform infiltration is a specific imaging marker of molecular glioblastomas that can help distinguishing these tumors from IDH-mutant lower-grade gliomas.


Sujet(s)
Tumeurs du cerveau , Glioblastome , Gliome , Marqueurs biologiques , Tumeurs du cerveau/imagerie diagnostique , Tumeurs du cerveau/génétique , Glioblastome/imagerie diagnostique , Glioblastome/génétique , Gliome/anatomopathologie , Humains , Isocitrate dehydrogenases/génétique , Mutation
5.
Eur Urol Focus ; 8(3): 769-776, 2022 05.
Article de Anglais | MEDLINE | ID: mdl-33931361

RÉSUMÉ

BACKGROUND: Superselective clamping of tumor-targeted arteries aims to eliminate ischemia of the remnant kidney while keeping tumor bed bloodless during excision. OBJECTIVE: To evaluate the impact of superselective clamping on long-term renal function, compared with renal artery early unclamping. DESIGN, SETTING, AND PARTICIPANTS: A randomized monocentric single-blind trial (1:1) was conducted from February 2018 to August 2019. Patients with a single renal tumor were candidates for a robot-assisted partial nephrectomy (RAPN) in a referral center. EMERALD (NCT03679572) was powered to include 50 patients with an interim analysis after 30 cases. INTERVENTION: Superselective RAPN (SS-RAPN) with near-infrared fluorescence (NIRF) or conventional RAPN with renal artery early unclamping. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The primary endpoint was the percent change of estimated glomerular filtration rate (eGFR) in the operated kidney after 6 mo (combination of eGFR and relative function on 99mTc-DMSA scintigraphy). Secondary endpoints assessed feasibility and safety of the technique. RESULTS AND LIMITATIONS: Relative eGFR reduction in the operated kidney at 6 mo did not differ significantly (-21.4% vs -23.4%, p=0.66). This absence of difference remained after adjusting on percentage of kidney volume preserved, which was an independent predictor of functional preservation. There were no significant differences in terms of blood loss, change in hemoglobin, postoperative complications, transfusion, and conversion to radical nephrectomy (two vs zero) or to open surgery (one vs zero). Despite a good accrual, the steering committee interrupted the trial after the interim analysis for futility given the absence of trend in favor of SS-RAPN. CONCLUSIONS: SS-RAPN using NIRF does not provide better renal function preservation than renal artery clamping, questioning the interest of this technique at a higher risk of bleeding. PATIENT SUMMARY: In this randomized controlled trial, superselective clamping of tumor feeding arteries did not show any advantage in terms of long-term renal function compared with conventional artery clamping.


Sujet(s)
Interventions chirurgicales robotisées , Robotique , Constriction , Humains , Ischémie/prévention et contrôle , Ischémie/chirurgie , Rein/vascularisation , Rein/physiologie , Rein/chirurgie , Néphrectomie/effets indésirables , Néphrectomie/méthodes , Artère rénale/chirurgie , Études rétrospectives , Interventions chirurgicales robotisées/effets indésirables , Interventions chirurgicales robotisées/méthodes , Méthode en simple aveugle , Résultat thérapeutique
6.
Neurooncol Adv ; 3(1): vdab061, 2021.
Article de Anglais | MEDLINE | ID: mdl-34056608

RÉSUMÉ

BACKGROUND: Diffuse hemispheric gliomas, H3 G34-mutant (DHG H3G34-mutant) constitute a distinct type of aggressive brain tumors. Although initially described in children, they can also affect adults. The aims of this study were to describe the characteristics of DHG H3G34-mutant in adults and to compare them to those of established types of adult WHO grade IV gliomas. METHODS: The characteristics of 17 adult DHG H3G34-mutant, 32 H3.3 K27M-mutant diffuse midline gliomas (DMG), 100 IDH-wildtype, and 36 IDH-mutant glioblastomas were retrospectively analyzed. RESULTS: Median age at diagnosis in adult DHG H3G34-mutant was 25 years (range: 19-33). All tumors were hemispheric. For 9 patients (56%), absent or faint contrast enhancement initially suggested another diagnosis than a high-grade glioma, and diffusion-weighted imaging seemed retrospectively more helpful to suspect an aggressive tumor than MR-spectroscopy and perfusion MRI. All cases were IDH-wildtype. Most cases were immunonegative for ATRX (93%) and Olig2 (100%) and exhibited MGMT promoter methylation (82%). The clinical and radiological presentations of adult DHG H3G34-mutant were different from those of established types of adult grade IV gliomas. Median overall survival of adult DHG H3G34-mutant was 12.4 months compared to 19.6 months (P = .56), 11.7 months (P = .45), and 50.5 months (P = .006) in H3.3 K27M-mutant DMG, IDH-wildtype, and IDH-mutant glioblastomas, respectively. CONCLUSIONS: Adult DHG H3G34-mutant are associated with distinct characteristics compared to those of established types of adult WHO grade IV gliomas. This study supports considering these tumors as a new type of WHO grade IV glioma in future classifications.

8.
World J Urol ; 39(7): 2775-2781, 2021 Jul.
Article de Anglais | MEDLINE | ID: mdl-33175210

RÉSUMÉ

PURPOSE: Living donor nephrectomy is a high-stake procedure involving healthy individuals, therefore every effort should be made to define each patient's individualized risk and improve potential donors' information. The aim of this study was to evaluate the interest of the Mayo adhesive probability (MAP) score, an imaging-based score initially designed to estimate the risk of adherent perinephric fat in partial nephrectomy, to predict intra- and postoperative complications of living donor nephrectomy. MATERIALS AND METHODS: We retrospectively reviewed the imaging, clinical, and follow-up data of 452 kidney donors who underwent laparoscopic donor nephrectomy in two academic centers. RESULTS: Imaging and follow-up data were available for 307 kidney donors, among which 44 (14%) had a high MAP score (≥ 3). Intraoperative difficulties were encountered in 50 patients (16%), including difficult dissection (n = 35) and bleeding (n = 17). Conversion to open surgery was required for 13 patients (4.2%). On multivariate analysis, a MAP score ≥ 3 was significantly associated with the risk of intraoperative difficulty [OR 14.12 (5.58-35.7), p < 0.001] or conversion to open surgery [OR 18.96 (3.42-105.14), p = 0.0042]. Postoperative complications were noted in 99 patients (32%), including 12 patients (3.9%) with Clavien-Dindo grade III-IV complications. On multivariate analysis, a high MAP score was also associated with the risk of postoperative complications [OR 2.55 (1.20-5.40), p = 0.01]. CONCLUSIONS: In this retrospective bicentric study, a high MAP score was associated with the risk of intra- and postoperative complications of laparoscopic donor nephrectomy. The MAP score appears of interest in the living donor evaluation process to help improve donors' information and outcomes.


Sujet(s)
Laparoscopie , Néphrectomie/effets indésirables , Néphrectomie/méthodes , Prélèvement d'organes et de tissus/méthodes , Adulte , Femelle , Humains , Complications peropératoires , Mâle , Adulte d'âge moyen , Complications postopératoires , Études rétrospectives
9.
J Neuropathol Exp Neurol ; 79(9): 1011-1014, 2020 09 01.
Article de Anglais | MEDLINE | ID: mdl-32770176

RÉSUMÉ

Pleomorphic xanthoastrocytoma (PXA) is classified as an astrocytic glioma occurring most often in children or young adults. Molecular alterations in PXA are not fully known, especially those associated with tumor progression. We describe a patient with several relapses of a PXA. The tumor showed an acquired ATRX loss through tumor evolution. We tested alternative lengthening of telomeres (ALT) with the C-circle test. While the test was negative in the first tumor, a high circle activity was detected in the last relapse, suggesting an acquired ALT phenotype. Our data not only confirm previous findings of the possible occurrence of ATRX mutations in PXA but also suggest that this alteration is linked to PXA progression. In small biopsies, tumors with ATRX loss, without IDH or histone mutation, pathologists should consider the diagnosis of PXA, especially if associated with BRAF V600E mutation, CDKN2A deletion, and ALT.


Sujet(s)
Astrocytome/génétique , Tumeurs du cerveau/génétique , Récidive tumorale locale/génétique , Homéostasie des télomères/génétique , Protéine nucléaire liée à l'X/génétique , Astrocytome/anatomopathologie , Tumeurs du cerveau/anatomopathologie , Évolution de la maladie , Femelle , Humains , Mutation , Récidive tumorale locale/anatomopathologie , Phénotype , Jeune adulte
10.
Neurosurgery ; 87(4): E513-E519, 2020 09 15.
Article de Anglais | MEDLINE | ID: mdl-32107549

RÉSUMÉ

BACKGROUND: Biopsies in patients with a suspected glioma are occasionally nondiagnostic. OBJECTIVE: To explore the utility of molecular testing in this setting by determining whether IDH1 and TERT promoter (pTERT) mutations could be detected in nondiagnostic biopsies from glioma patients. METHODS: Using SNaPshot polymerase chain reaction, we retrospectively assessed IDH1 and pTERT mutation status in nondiagnostic biopsies from 28 glioma patients. RESULTS: The nondiagnostic biopsy (needle biopsy n = 25, open or endoscopic biopsy n = 3) consisted of slight glial cell hypercellularity, hemorrhage, and/or necrosis. After another biopsy (n = 23) or a subsequent surgical resection (n = 5) the diagnosis was an IDH1-wildtype (WT) pTERT-mutant glioma (glioblastoma n = 16, astrocytoma n = 4), an IDH1-mutant pTERT-mutant oligodendroglioma (n = 1), an IDH1-mutant pTERT-WT astrocytoma (n = 1), and an IDH1-WT pTERT-WT glioblastoma (n = 6). An IDH1 mutation was identified in the nondiagnostic biopsies of the 2 IDH-mutant gliomas, and a pTERT mutation in the nondiagnostic biopsies of 16 out of the 21 of pTERT mutant-gliomas (76%). Overall, an IDH1 and/or a pTERT mutation were detected in 17 out of 28 (61%) of nondiagnostic biopsies. Retrospective analysis of the nondiagnostic biopsies based on these results and on imaging characteristics suggested that a new biopsy could have been avoided in 6 patients in whom a diagnosis of "molecular glioblastoma" could have been done with a high level of confidence. CONCLUSION: In the present series, IDH1 and pTERT mutations could be detected in a high proportion of nondiagnostic biopsies from glioma patients. Molecular testing may facilitate the interpretation of nondiagnostic biopsies in patients with a suspected glioma.


Sujet(s)
Tumeurs du cerveau/génétique , Gliome/génétique , Isocitrate dehydrogenases/génétique , Mutation/génétique , Régions promotrices (génétique)/génétique , Telomerase/génétique , Adulte , Sujet âgé , Sujet âgé de 80 ans ou plus , Biopsie , Tumeurs du cerveau/anatomopathologie , Femelle , Gliome/anatomopathologie , Humains , Mâle , Adulte d'âge moyen , Études rétrospectives
11.
Oncogene ; 39(15): 3056-3074, 2020 04.
Article de Anglais | MEDLINE | ID: mdl-32066881

RÉSUMÉ

The Bcl-xL apoptosis inhibitor plays a major role in vertebrate development. In addition to its effect on apoptosis, Bcl-xL is also involved in cell migration and mitochondrial metabolism. These effects may favour the onset and dissemination of metastasis. However, the underlying molecular mechanisms remain to be fully understood. Here we focus on the control of cell migration by Bcl-xL in the context of breast cancer cells. We show that Bcl-xL silencing led to migration defects in Hs578T and MDA-MB231 cells. These defects were rescued by re-expressing mitochondria-addressed, but not endoplasmic reticulum-addressed, Bcl-xL. The use of BH3 mimetics, such as ABT-737 and WEHI-539 confirmed that the effect of Bcl-xL on migration did not depend on interactions with BH3-containing death accelerators such as Bax or BH3-only proteins. In contrast, the use of a BH4 peptide that disrupts the Bcl-xL/VDAC1 complex supports that Bcl-xL by acting on VDAC1 permeability contributes to cell migration through the promotion of reactive oxygen species production by the electron transport chain. Collectively our data highlight the key role of Bcl-xL at the interface between cell metabolism, cell death, and cell migration, thus exposing the VDAC1/Bcl-xL interaction as a promising target for anti-tumour therapy in the context of metastatic breast cancer.


Sujet(s)
Tumeurs du sein/anatomopathologie , Mitochondries/métabolisme , Espèces réactives de l'oxygène/métabolisme , Protéine bcl-X/métabolisme , Acide 4,4'-diisothiocyano-stilbène-2,2'-disulfonique/pharmacologie , Acide 4,4'-diisothiocyano-stilbène-2,2'-disulfonique/usage thérapeutique , Animaux , Antinéoplasiques/pharmacologie , Antinéoplasiques/usage thérapeutique , Apoptose/effets des médicaments et des substances chimiques , Apoptose/génétique , Dérivés du biphényle/pharmacologie , Dérivés du biphényle/usage thérapeutique , Région mammaire/anatomopathologie , Tumeurs du sein/traitement médicamenteux , Lignée cellulaire tumorale , Mouvement cellulaire/effets des médicaments et des substances chimiques , Mouvement cellulaire/génétique , Modèles animaux de maladie humaine , Femelle , Techniques de knock-down de gènes , Humains , Métastase lymphatique/anatomopathologie , Mitochondries/effets des médicaments et des substances chimiques , Invasion tumorale/génétique , Invasion tumorale/anatomopathologie , Invasion tumorale/prévention et contrôle , Nitrophénols/pharmacologie , Nitrophénols/usage thérapeutique , Pipérazines/pharmacologie , Pipérazines/usage thérapeutique , Liaison aux protéines/effets des médicaments et des substances chimiques , Petit ARN interférent/métabolisme , Sulfonamides/pharmacologie , Sulfonamides/usage thérapeutique , Canal anionique-1 voltage-dépendant/antagonistes et inhibiteurs , Canal anionique-1 voltage-dépendant/métabolisme , Tests d'activité antitumorale sur modèle de xénogreffe , Danio zébré , Protéine bcl-X/antagonistes et inhibiteurs , Protéine bcl-X/génétique
12.
Acta Neuropathol Commun ; 7(1): 175, 2019 11 09.
Article de Anglais | MEDLINE | ID: mdl-31706351

RÉSUMÉ

All cancer cells need to maintain functional telomeres to sustain continuous cell division and proliferation. In human diffuse gliomas, functional telomeres are maintained due either to reactivation of telomerase expression, the main pathway in most cancer types, or to activation of a mechanism called the alternative lengthening of telomeres (ALT). The presence of IDH1/2 mutations (IDH-mutant) together with loss of ATRX expression (ATRX-lost) are frequently associated with ALT in diffuse gliomas. However, detection of ALT, and a fortiori its quantification, are rarely, if ever, measured in neuropathology laboratories. We measured the level of ALT activity using the previously described quantitative "C-circle" assay and analyzed it in a well characterized cohort of 104 IDH-mutant and ATRX-lost adult diffuse gliomas. We report that in IDH-mutant ATRX-lost anaplastic astrocytomas, the intensity of ALT was inversely correlated with age (p < 0.001), the younger the patient, the higher the intensity of ALT. Strikingly, glioblastomas having progressed from anaplastic astrocytomas did not exhibit this correlation. ALT activity level in the tumor did not depend on telomere length in healthy tissue cells from the same patient. In summary, we have uncovered the existence, in anaplastic astrocytomas but not in glioblastomas with the same IDH and ATRX mutations, of a correlation between patient age and the level of activity of ALT, a telomerase-independent pathway of telomere maintenance.


Sujet(s)
Astrocytome/métabolisme , Tumeurs du cerveau/métabolisme , Isocitrate dehydrogenases/physiologie , Homéostasie des télomères/physiologie , Protéine nucléaire liée à l'X/biosynthèse , Adulte , Sujet âgé , Astrocytome/génétique , Astrocytome/anatomopathologie , Tumeurs du cerveau/génétique , Tumeurs du cerveau/anatomopathologie , Études de cohortes , Femelle , Régulation de l'expression des gènes tumoraux , Humains , Mâle , Adulte d'âge moyen , Mutation/physiologie , Protéine nucléaire liée à l'X/génétique
13.
Int J Mol Sci ; 20(19)2019 Oct 08.
Article de Anglais | MEDLINE | ID: mdl-31597307

RÉSUMÉ

Senescence is defined as a stress-induced durable cell cycle arrest. We herein revisit the origin of two of these stresses, namely mitochondrial metabolic compromise, associated with reactive oxygen species (ROS) production, and replicative senescence, activated by extreme telomere shortening. We discuss how replication stress-induced DNA damage of telomeric DNA (telDNA) and mitochondrial DNA (mtDNA) can be considered a common origin of senescence in vitro, with consequences on ageing in vivo. Unexpectedly, mtDNA and telDNA share common features indicative of a high degree of replicative stress, such as G-quadruplexes, D-loops, RNA:DNA heteroduplexes, epigenetic marks, or supercoiling. To avoid these stresses, both compartments use similar enzymatic strategies involving, for instance, endonucleases, topoisomerases, helicases, or primases. Surprisingly, many of these replication helpers are active at both telDNA and mtDNA (e.g., RNAse H1, FEN1, DNA2, RecQ helicases, Top2α, Top2ß, TOP3A, DNMT1/3a/3b, SIRT1). In addition, specialized telomeric proteins, such as TERT (telomerase reverse transcriptase) and TERC (telomerase RNA component), or TIN2 (shelterin complex), shuttle from telomeres to mitochondria, and, by doing so, modulate mitochondrial metabolism and the production of ROS, in a feedback manner. Hence, mitochondria and telomeres use common weapons and cooperate to resist/prevent replication stresses, otherwise producing common consequences, namely senescence and ageing.


Sujet(s)
Réplication de l'ADN , ADN mitochondrial/génétique , Stress physiologique/génétique , Télomère/génétique , Vieillissement/génétique , Animaux , Vieillissement de la cellule/génétique , Altération de l'ADN , Épigenèse génétique , Humains , Mitochondries/génétique , Mitochondries/métabolisme , Stress oxydatif , Homéostasie des télomères , Raccourcissement des télomères
14.
Mol Diagn Ther ; 23(4): 537-545, 2019 08.
Article de Anglais | MEDLINE | ID: mdl-31087282

RÉSUMÉ

BACKGROUND AND OBJECTIVE: Genomic duplications and fusion involving BRAF and KIAA1549 that create fusion proteins with constitutive B-RAF kinase activity are a hallmark of pilocytic astrocytomas (PAs). The detection of KIAA1549-BRAF fusion transcripts is of paramount importance to classify these tumors and to identify patients who could benefit from BRAF inhibitors. In a clinical setting, the available material for molecular analysis from these pediatric tumors is often limited to formalin-fixed paraffin-embedded (FFPE) tissue. The aim of the present study was to develop a new method to detect the three most frequent KIAA1549-BRAF fusion transcripts, 15-9, 16-11, and 16-9, where numbers refer to the exons fused together, using a FFPE-compatible multiplex quantitative reverse transcription polymerase chain reaction (qRT-PCR). METHODS: We compared performance of the assay to a reference singleplex method on a collection of 46 FFPE PAs. RESULTS: The results showed that both methods are comparable. The multiplex method had an overall 97% sensitivity and 100% specificity compared to the singleplex method, and agreement between the two techniques was almost perfect (Cohen's kappa: 0.97). There was no evidence of a significant difference between the qRT-PCR efficiencies of the multiplex technique and of the singleplex assay for all fusion transcripts and for GAPDH, the latter used as a reference gene. The multiplex method consumed four times less complementary DNA (cDNA), cost less, and required half the hands-on technical time. CONCLUSION: The results show that it could be beneficial to implement the multiplex method in a clinical setting, where samples presenting low quantity of degraded RNA are not unusual.


Sujet(s)
Astrocytome/génétique , Réaction de polymérisation en chaine multiplex , Protéines de fusion oncogènes/génétique , Réaction de polymérisation en chaine en temps réel , Adolescent , Astrocytome/diagnostic , Biopsie , Analyse coût-bénéfice , Femelle , Fréquence d'allèle , Humains , Mâle , Réaction de polymérisation en chaine multiplex/méthodes , Grading des tumeurs , Inclusion en paraffine , Réaction de polymérisation en chaine en temps réel/méthodes , Reproductibilité des résultats
15.
Neurosurgery ; 85(3): E448-E456, 2019 09 01.
Article de Anglais | MEDLINE | ID: mdl-30407589

RÉSUMÉ

BACKGROUND: Adult IDH-wildtype astrocytomas with TERT promoter mutations (TERTp) are associated with a poor prognosis. OBJECTIVE: To analyze the radiological presentation and natural history of adult IDH-wildtype astrocytomas with TERTp. METHODS: We retrospectively reviewed the characteristics of 40 IDH-wildtype TERTp-mutant astrocytomas (grade II n = 19, grade III n = 21) and compared them to those of 114 IDH-mutant lower grade gliomas (LGG), of 92 IDH-wildtype TERTp-mutant glioblastomas, and of 15 IDH-wildtype TERTp-wildtype astrocytomas. RESULTS: Most cases of IDH-wildtype TERTp-mutant astrocytomas occurred in patients aged >50 yr (88%) and presented as infiltrative lesions without contrast enhancement (73%) that were localized in the temporal and/or insular lobes (37.5%) or corresponded to a gliomatosis cerebri (43%). Thalamic involvement (33%) and extension to the brainstem (27%) were frequently observed, as was gyriform infiltration (33%). This radiological presentation was different from that of IDH-mutant LGG, IDH-wildtype TERTp-mutant glioblastomas, and IDH-wildtype TERTp-wildtype astrocytomas. Tumor evolution before treatment initiation was assessable in 17 cases. Ten cases demonstrated a rapid growth characterized by the apparition of a ring-like contrast enhancement and/or a median velocity of diametric expansion (VDE) ≥8 mm/yr but 7 cases displayed a slow growth (VDE <8 mm/yr) that could last several years before anaplastic transformation. Median overall survival of IDH-wildtype TERTp-mutant astrocytomas was 27 mo. CONCLUSION: IDH-wildtype TERTp-mutant astrocytomas typically present as nonenhancing temporo-insular infiltrative lesions or as gliomatosis cerebri in patients aged >50 yr. In the absence of treatment, although rapid tumor growth is frequent, an initial falsely reassuring, slow growth can be observed.


Sujet(s)
Tumeurs du cerveau/génétique , Tumeurs du cerveau/anatomopathologie , Gliome/génétique , Gliome/anatomopathologie , Adulte , Sujet âgé , Évolution de la maladie , Femelle , Humains , Isocitrate dehydrogenases/génétique , Adulte d'âge moyen , Mutation , Régions promotrices (génétique) , Études rétrospectives , Telomerase/génétique
17.
J Trauma Acute Care Surg ; 84(6): 951-955, 2018 06.
Article de Anglais | MEDLINE | ID: mdl-29462089

RÉSUMÉ

BACKGROUND: To evaluate the management and long-term renal function with DMSA scintigraphy in pediatric severe traumatic kidney injury grade IV and V at the trauma center of Grenoble Teaching Hospital. METHODS: This is a single-center observational retrospective study between 2004 and 2014. All children younger than 15 years and managed at the Grenoble teaching Hospital for a severe trauma kidney injury grade IV or V were included. The trauma grade was radiologically diagnosed on arrival at hospital, using the classification of the American Association for Surgery of Trauma. The management followed the algorithm in effect in the establishment. The assessment of the renal function was performed by a DMSA scintigraphy after at least 6 months from the injury. RESULTS: Twenty-one children were managed for a severe renal trauma (16 IV and 5 V). The diagnosis was initially made by an ultrasonography (eight cases) or a computed tomography scan (13 cases). A child with a severe renal trauma IV underwent nephrectomy on day 6 of the trauma. Eleven children needed a therapeutic procedure (three embolizations, four double J stents, one arterial stent, one peritoneal lavage for a splenic hemoperitoneum, four pleural drainages). A DMSA scintigraphy was performed in 15 patients to assess the function of the injured kidney: 11 of 16 severe renal trauma IV with an average of 39.4%, and 17% in 4 of 5 severe renal trauma V analyzed. CONCLUSION: Among the 21 children managed for a severe kidney trauma injury IV or V, 11 required a therapeutic procedure, one of them a nephrectomy. The DMSA scintigraphy performed after at least 6 months from the trauma found an injured renal function at 39.4% in 11 of 16 severe renal trauma IV analyzed, and 17% in 4 of 5 severe renal trauma V analyzed, which confirms the currently conservative management. LEVEL OF EVIDENCE: Type of study: original article, retrospective observational study, level IV.


Sujet(s)
Atteinte rénale aigüe/imagerie diagnostique , Atteinte rénale aigüe/physiopathologie , Atteinte rénale aigüe/thérapie , Tomographie par émission monophotonique , Adolescent , Enfant , Femelle , Humains , Score de gravité des lésions traumatiques , Tests de la fonction rénale , Mâle , Radiopharmaceutiques , Études rétrospectives , Succimer de technétium (99mTc) , Tomodensitométrie , Résultat thérapeutique
18.
Int. braz. j. urol ; 44(1): 53-62, Jan.-Feb. 2018. tab
Article de Anglais | LILACS | ID: biblio-892939

RÉSUMÉ

ABSTRACT Introduction Super-selective clamping of tumor-specific segmental arteries was developed to eliminate ischemia of the remnant kidney while limiting hemorrhage during partial nephrectomy. The objective is to evaluate the benefice of super-selective clamping on renal functional outcome, compared to early-unclamping of the renal artery. Materials and Methods From March 2015 to July 2016, data from 30 patients undergoing super-selective robot-assisted PN (RAPN) for a solitary tumor by a single surgeon were prospectively collected. Tumor devascularization was assessed using indocyanine green near-infrared fluorescence. A matched-pair analysis with a retrospective cohort undergoing early-unclamping was conducted, adjusting on tumor complexity and preoperative eGFR. Perioperative, oncologic and functional outcomes using DMSA-renal scintigraphy were assessed. Multivariate analysis was performed to identify predictors of postoperative renal function and de novo chronic kidney disease (CKD). Results Super-selective RAPN was successful in 23/30 patients (76.7%), 5 requiring secondary main artery clamping due to persistent tumor fluorescence. Matched-pair analysis showed similar operating time, blood loss, positives margins and complication rates. Super-selective clamping was associated with an improved eGFR variation at discharge (p=0.002), 1-month (p=0.01) and 6-month post-op (-2%vs-16% p=0.001). It also led to a better relative function on scintigraphy (46%vs40% p=0.04) and homolateral eGFR (p=0.04), and fewer upstaging to CKD stage ≥3 (p=0.03). On multivariate analysis, super-selective clamping was a predictor of postoperative renal function. Conclusion Super-selective RAPN leads to an improved preservation of renal function and a reduced risk of de novo CKD stage≥3, while keeping the benefit of main artery clamping on perioperative outcomes.


Sujet(s)
Humains , Mâle , Femelle , Sujet âgé , Artère rénale , Interventions chirurgicales robotisées/méthodes , Ischémie/prévention et contrôle , Tumeurs du rein/chirurgie , Tumeurs du rein/vascularisation , Néphrectomie/méthodes , Soins postopératoires , Études rétrospectives , Résultat thérapeutique , Interventions chirurgicales mini-invasives , Constriction , Spectroscopie proche infrarouge , Adulte d'âge moyen
19.
J Neurooncol ; 136(3): 555-563, 2018 Feb.
Article de Anglais | MEDLINE | ID: mdl-29196927

RÉSUMÉ

Adult cerebellar glioblastomas (cGBM) are rare and their characteristics remain to be fully described. We analyzed the characteristics of 17 adult patients with cGBM and compared them to a series of 103 patients presenting a supra-tentorial glioblastoma (stGBM). The mean age at GBMc diagnosis was 53.4 years (range 28-77). A history of neurofibromatosis type I was noted in 3 patients. cGBM were hemispheric in 10 patients (58.8%), only vermian in 4 patients (23.5%), and both vermian and hemispheric in 3 patients (17.7%). A H3 K27M mutation was identified in 3/14 patients, a TERT promoter mutation in 3/14 patients and a methylated MGMT promoter in 3/14 patients. None of the patients (0/14) harbored an EGFR amplification, an IDH or a BRAF mutation. Association with neurofibromatosis type I and H3K27M mutations were mutually exclusive. Compared with stGBM, cGBM occurred in younger patients (53.4 vs. 63.2, p = 0.02), were more frequently associated with neurofibromatosis type I (18 vs. 1%, p = 0.009) and with a H3 K27M mutation (21 vs. 3%, p = 0.02). They also tended to have a more frequent multifocal presentation at diagnosis (21 vs. 4.3%, p = 0.06), more frequently resulted in leptomeningeal or intra-axial metastasis (44.5 vs. 5%, p = 0.002) and were associated with a shorter median overall survival (5.9 vs. 14.2 months, p = 0.004). The present study suggests that adult cGBM differ from their supra-tentorial counterpart and constitute a heterogeneous group of IDH wild-type gliomas with at least two subgroups, one associated with H3K27M mutations and the other with neurofibromatosis type I.


Sujet(s)
Tumeurs du cervelet/épidémiologie , Glioblastome/épidémiologie , Adulte , Facteurs âges , Sujet âgé , Tumeurs du cervelet/génétique , Femelle , Études de suivi , Glioblastome/génétique , Humains , Mâle , Adulte d'âge moyen , Mutation , Neurofibromatose de type 1/épidémiologie , Études rétrospectives , Tumeurs sus-tentorielles/épidémiologie , Tumeurs sus-tentorielles/génétique
20.
Int Braz J Urol ; 44(1): 53-62, 2018.
Article de Anglais | MEDLINE | ID: mdl-29144626

RÉSUMÉ

INTRODUCTION: Super-selective clamping of tumor-specific segmental arteries was developed to eliminate ischemia of the remnant kidney while limiting hemorrhage during partial nephrectomy. The objective is to evaluate the benefice of super-selective clamping on renal functional outcome, compared to early-unclamping of the renal artery. MATERIALS AND METHODS: From March 2015 to July 2016, data from 30 patients undergoing super-selective robot-assisted PN (RAPN) for a solitary tumor by a single surgeon were prospectively collected. Tumor devascularization was assessed using indocyanine green near-infrared fluorescence. A matched-pair analysis with a retrospective cohort undergoing early-unclamping was conducted, adjusting on tumor complexity and preoperative eGFR. Perioperative, oncologic and functional outcomes using DMSA-renal scintigraphy were assessed. Multivariate analysis was performed to identify predictors of postoperative renal function and de novo chronic kidney disease (CKD). RESULTS: Super-selective RAPN was successful in 23/30 patients (76.7%), 5 requiring secondary main artery clamping due to persistent tumor fluorescence. Matched-pair analysis showed similar operating time, blood loss, positives margins and complication rates. Super-selective clamping was associated with an improved eGFR variation at discharge (p=0.002), 1-month (p=0.01) and 6-month post-op (-2%vs-16% p=0.001). It also led to a better relative function on scintigraphy (46%vs40% p=0.04) and homolateral eGFR (p=0.04), and fewer upstaging to CKD stage ≥3 (p=0.03). On multivariate analysis, super-selective clamping was a predictor of postoperative renal function. CONCLUSION: Super-selective RAPN leads to an improved preservation of renal function and a reduced risk of de novo CKD stage≥3, while keeping the benefit of main artery clamping on perioperative outcomes.


Sujet(s)
Ischémie/prévention et contrôle , Tumeurs du rein/vascularisation , Tumeurs du rein/chirurgie , Néphrectomie/méthodes , Artère rénale , Interventions chirurgicales robotisées/méthodes , Sujet âgé , Constriction , Femelle , Humains , Mâle , Adulte d'âge moyen , Interventions chirurgicales mini-invasives , Soins postopératoires , Études rétrospectives , Spectroscopie proche infrarouge , Résultat thérapeutique
SÉLECTION CITATIONS
DÉTAIL DE RECHERCHE
...