35 research outputs found
Discrimination between two different grades of human glioma based on blood vessel infrared spectral imaging
Gliomas are brain tumours classified into four grades with increasing malignancy from I to IV. The development and the progression of malignant glioma largely depend on the tumour vascularization. Due to their tissue heterogeneity, glioma cases can be difficult to classify into a specific grade using the gold standard of histological observation, hence the need to base classification on a quantitative and reliable analytical method for accurately grading the disease. Previous works focused specifically on vascularization study by Fourier transform infrared (FTIR) spectroscopy, proving this method to be a way forward to detect biochemical changes in the tumour tissue not detectable by visual techniques. In this project, we employed FTIR imaging using a focal plane array (FPA) detector and globar source to analyse large areas of glioma tumour tissue sections via molecular fingerprinting in view of helping to define markers of the tumour grade. Unsupervised multivariate analysis (hierarchical cluster analysis and principal component analysis) of blood vessel spectral data, retrieved from the FPA images, revealed the fine structure of the borderline between two areas identified by a pathologist as grades III and IV. Spectroscopic indicators are found capable of discriminating different areas in the tumour tissue and are proposed as biomolecular markers for potential future use of grading gliomas. Graphical Abstract Infrared imaging of glioma blood vessels provides a means to revise the pathologists' line of demarcation separating grade III (GIII) from grade IV (GIV) parts
Long-term outcomes of CLIPPERS (chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids) in a consecutive series of 12 patients.
BACKGROUND: Chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS) is a central nervous system inflammatory disease.
OBJECTIVE: To describe the disease course of CLIPPERS.
DESIGN: A nationwide study was implemented to collect clinical, magnetic resonance imaging, cerebrospinal fluid, and brain biopsy specimen characteristics of patients with CLIPPERS.
SETTING: Academic research.
PATIENTS: Twelve patients with CLIPPERS.
MAIN OUTCOME MEASURES: The therapeutic management of CLIPPERS was evaluated.
RESULTS: Among 12 patients, 42 relapses were analyzed. Relapses lasted a mean duration of 2.5 months, manifested frequent cerebellar ataxia and diplopia, and were associated with a mean Expanded Disability Status Scale (EDSS) score of 4. Besides typical findings of CLIPPERS, magnetic resonance imaging showed brainstem mass effect in 5 patients, extensive myelitis in 3 patients, and closed ring enhancement in 1 patient. Inconstant oligoclonal bands were found on cerebrospinal fluid investigation in 4 patients, with an increased T-cell ratio of CD4 to CD8. Among 7 available brain biopsy specimens, staining was positive for perivascular CD4 T lymphocytes in 5 samples. Thirty-eight of 42 relapses were treated with pulse corticosteroid therapy, which led to improvement, with a mean residual EDSS score of 1.9 (range, 0-7). In 1 patient with untreated relapses, scores on the EDSS progressively increased to a score of 10 at death. Among 5 patients without long-term corticosteroid therapy, the mean annualized relapse rate was 0.5 (range, 0.25-2.8). Among 7 patients taking oral corticosteroids, no relapses occurred in those whose daily dose was 20 mg or higher. No progressive course of CLIPPERS was observed. Four patients with a final EDSS score of 4 or higher had experienced previous severe relapses (EDSS score, ≥5) and brainstem and spinal cord atrophy.
CONCLUSIONS: CLIPPERS is a relapsing-remitting disorder without progressive forms. Long-term disability is correlated with the severity of previous relapses. Further studies are needed to confirm that prolonged corticosteroid therapy prevents further relapses.journal article2012 Julimporte
Study of erlotinib-induced responses in glioblastoma cell lines
Le glioblastome (GBM), tumeur de plus haut grade du système nerveux central (OMS grade 4) a un pronostic très sombre, quelque soit le traitement, lié à une résistance à l’apoptose. L’erlotinib (Tarceva®, OSI 774) est un inhibiteur de la tyrosine kinase du récepteur au facteur de croissance épithélial (EGFR). L’hyper-expression et l’amplification du gène de l’EGFR dans 40 à 60% des GBM, fourni un rationnel pour utiliser l’erlotinib. Nous avons montré sur U87-MG et DBTRG-05MG, deux lignées de GBM, l’absence d’apoptose avec l’erlotinib, liée soit à un déficit en pro-caspase 3, soit à une accumulation d’αB-crystalline bloquant l’activation de la caspase-3. L’absence d’apoptose dévie alors la cellule vers l’autophagie. L’inhibition de l’autophagie par ARN interférents ou par la chloroquine permet d’obtenir une synergie avec l’erlotinib en induisant la mort des cellules tumorales à des doses acceptables.Les GBM ont composition cellulaire hétérogène, avec un petit nombre d’éléments appelés cellules souches cancéreuses (CSC). Douées d’auto-renouvellement, elles participent à la propagation tumorale et à la résistance aux traitements. Nous avons testé l’erlotinib sur trois lignées issues de GBM humains, ayant deux modes de croissance distincts selon les conditions de milieu: en neurosphères (NS) et de type adhérent. Erlotinib a un effet inhibiteur minime sur les trois lignées adhérentes, alors que l’effet est significatif sur les lignées NS, traduisant l’importance de la voie d’EGFR pour les NS. Dans les lignées en NS, l’erlotinib est efficace sur les cellules progénitrices, mais n’a pas d’action ni sur les cellules initiatrices de NS, ni sur les cellules différenciées. L’auto-renouvellement des NS n’est pas non plus altéré. L’association cyclopamine, inhibiteur pharmacologique de la voie de Hedgehog, -erlotinib est synergique en bloquant la croissance et l’initiation des NS, laissant présager une efficacité sur les CSC. Les résultats obtenus sur ces différents modèles permettent d’une part de préciser certains mécanismes de résistance des cellules de GBM, et aussi d’orienter les indications et le choix des traitements susceptibles d’être les plus efficaces.Glioblastoma (GBM) is the most common primary central nervous system tumor in adults and the prognosis remains dismal, any treatment used. Epidermal Growth Factor Receptor (EGFR) is amplified, overexpressed, and/or mutated in GBM, making it a rational for therapy. Erlotinib, an EGFR kinase inhibitor is strongly associated with clinical response in several cancers. We showed for U87-MG and DBTRG-05MG, two human GBM cell lines, that erlotinib can’t trigger apoptosis, related either to accumulation of αB-crystallin capable to impair caspase 3 cleavage, or to constitutive deficit for procaspase 3 in DBTRG-05MG. Apoptosis deficit switches the cell to autophagic process. Inhibition of autophagy with RNA interference or chloroquine resulted in sensitization of U87 and allowed a synergistic effect with erlotinib at therapeutic doses.Moreover, GBM showed a heterogeneous cell composition with cancer stem cells, progenitors and more differentiated cells. In this study, we test erlotinib in vitro on other GBM models: three cell lines established from surgically resected GBM specimens, grown along two features adherent and neurospheres. On the three differentiated adhering cell lines, erlotinib had only a moderate activity. Conversely, on neurosphere forming cell lines, erlotinib induced a strong inhibition of cell growth related to the EGFR amplification and EGFR expression. A short erlotinib exposure induced cell death primarily in nestin-positive cells; however it was found without effect on neurosphere initiating activity and self renewal. These results suggest that EGFR pathway activation is essential for the proliferation of GBM progenitor cells but dispensable for stem-like cancer cells self–renewal. As Hedgehog pathway is known to be activated in neural stem cells, we assayed the Hedgehog pathway inhibitor cyclopamine in association with erlotinib. While each drug separately was without effect on sphere initiation, their combination led to a 25 fold decrease in the sphere number (p=0.0004).These in vitro models are convenient to investigate resistance mechanisms in GBM. Furthermore, they focus on the necessity to exploit drug combinations for greatest efficiency
Study of erlotinib-induced responses in glioblastoma cell lines
Le glioblastome (GBM), tumeur de plus haut grade du système nerveux central (OMS grade 4) a un pronostic très sombre, quelque soit le traitement, lié à une résistance à l’apoptose. L’erlotinib (Tarceva®, OSI 774) est un inhibiteur de la tyrosine kinase du récepteur au facteur de croissance épithélial (EGFR). L’hyper-expression et l’amplification du gène de l’EGFR dans 40 à 60% des GBM, fourni un rationnel pour utiliser l’erlotinib. Nous avons montré sur U87-MG et DBTRG-05MG, deux lignées de GBM, l’absence d’apoptose avec l’erlotinib, liée soit à un déficit en pro-caspase 3, soit à une accumulation d’αB-crystalline bloquant l’activation de la caspase-3. L’absence d’apoptose dévie alors la cellule vers l’autophagie. L’inhibition de l’autophagie par ARN interférents ou par la chloroquine permet d’obtenir une synergie avec l’erlotinib en induisant la mort des cellules tumorales à des doses acceptables.Les GBM ont composition cellulaire hétérogène, avec un petit nombre d’éléments appelés cellules souches cancéreuses (CSC). Douées d’auto-renouvellement, elles participent à la propagation tumorale et à la résistance aux traitements. Nous avons testé l’erlotinib sur trois lignées issues de GBM humains, ayant deux modes de croissance distincts selon les conditions de milieu: en neurosphères (NS) et de type adhérent. Erlotinib a un effet inhibiteur minime sur les trois lignées adhérentes, alors que l’effet est significatif sur les lignées NS, traduisant l’importance de la voie d’EGFR pour les NS. Dans les lignées en NS, l’erlotinib est efficace sur les cellules progénitrices, mais n’a pas d’action ni sur les cellules initiatrices de NS, ni sur les cellules différenciées. L’auto-renouvellement des NS n’est pas non plus altéré. L’association cyclopamine, inhibiteur pharmacologique de la voie de Hedgehog, -erlotinib est synergique en bloquant la croissance et l’initiation des NS, laissant présager une efficacité sur les CSC. Les résultats obtenus sur ces différents modèles permettent d’une part de préciser certains mécanismes de résistance des cellules de GBM, et aussi d’orienter les indications et le choix des traitements susceptibles d’être les plus efficaces.Glioblastoma (GBM) is the most common primary central nervous system tumor in adults and the prognosis remains dismal, any treatment used. Epidermal Growth Factor Receptor (EGFR) is amplified, overexpressed, and/or mutated in GBM, making it a rational for therapy. Erlotinib, an EGFR kinase inhibitor is strongly associated with clinical response in several cancers. We showed for U87-MG and DBTRG-05MG, two human GBM cell lines, that erlotinib can’t trigger apoptosis, related either to accumulation of αB-crystallin capable to impair caspase 3 cleavage, or to constitutive deficit for procaspase 3 in DBTRG-05MG. Apoptosis deficit switches the cell to autophagic process. Inhibition of autophagy with RNA interference or chloroquine resulted in sensitization of U87 and allowed a synergistic effect with erlotinib at therapeutic doses.Moreover, GBM showed a heterogeneous cell composition with cancer stem cells, progenitors and more differentiated cells. In this study, we test erlotinib in vitro on other GBM models: three cell lines established from surgically resected GBM specimens, grown along two features adherent and neurospheres. On the three differentiated adhering cell lines, erlotinib had only a moderate activity. Conversely, on neurosphere forming cell lines, erlotinib induced a strong inhibition of cell growth related to the EGFR amplification and EGFR expression. A short erlotinib exposure induced cell death primarily in nestin-positive cells; however it was found without effect on neurosphere initiating activity and self renewal. These results suggest that EGFR pathway activation is essential for the proliferation of GBM progenitor cells but dispensable for stem-like cancer cells self–renewal. As Hedgehog pathway is known to be activated in neural stem cells, we assayed the Hedgehog pathway inhibitor cyclopamine in association with erlotinib. While each drug separately was without effect on sphere initiation, their combination led to a 25 fold decrease in the sphere number (p=0.0004).These in vitro models are convenient to investigate resistance mechanisms in GBM. Furthermore, they focus on the necessity to exploit drug combinations for greatest efficiency
Pasireotide-LAR in acromegaly patients treated with a combination therapy: a real-life study
Purpose Little data are available regarding the safety and efficacy of switching to Pasireotide-LAR monotherapy in acromegaly patients with partial resistance to first-generation somatostatin agonists (1gSRL) who require combination treatment with cabergoline or pegvisomant. Method In this monocentric prospective study within a tertiary university hospital, 15 consecutive acromegalic adults partially resistant to 1gSRL treated with octreotide LAR or lanreotide SR, and cabergoline ( n = 4, 3.5 mg/week) or pegvisomant ( n = 11, median dose 100 mg/week), were switched to Pasireotide-LAR (8 with 40 mg/month; 7 with 60 mg/month). Immunohistochemical expression level of SSTR5 and the granulation pattern of nine somatotroph adenomas were retrospectively determined to test for a correlation with the therapeutic efficacy of Pasireotide-LAR. Results Median IGF-1 concentration at the first evaluation (median 3 months) was similar to baseline (1.0 vs 1.1 ULN). 11/15 patients had IGF-1 levels ≤1.3 ULN before and after the switch but individual changes were variable. Hyperglycemia was frequent and greater in diabetic patients. 7/15 patients stopped Pasireotide-LAR due to lack of control of IGF-1 or intolerance. 8/15 patients received Pasireotide-LAR for a median of 29 months with IGF-1 levels ≤1.3 ULN and acceptable glucose tolerance (median HbA1c 6.1%). Two patients required initiation of oral antidiabetic treatment. The intensity of SSTR5 expression and the granulation pattern of adenomas were of limited value for the prediction of Pasireotide-LAR effectiveness. Conclusion Pasireotide-LAR may represent a suitable therapeutic alternative in a subset of acromegalic patients requiring combination therapy involving a 1gSR
1-D laser beam shaping using an adjustable binary diffractive optical element
International audienc
Cyclopamine cooperates with EGFR inhibition to deplete stem-like cancer cells in glioblastoma-derived spheroid cultures
International audienc
1-D laser beam shaping using an adjustable binary diffractive optical element
International audienc
Inflammatory Myofibroblastic Tumour of the Skull Base
Inflammatory myofibroblastic tumors (IMTs) are rare benign clinical and pathological entities. IMTs have been described in the lungs, abdomen, retroperitoneum, and extremities but rarely in the head and neck region. A 38-year-old man presented with headache, right exophthalmia, and right 6th nerve palsy. A CT scan revealed enlargement of the right cavernous sinus and osteolytic lesions of the right sphenoid and clivus. MR imaging showed a large tumor of the skull base which was invading the sella turcica, right cavernous sinus, and sphenoidal sinus. A biopsy was performed and revealed an IMT. Corticosteroids were given for 3 months but were inefficient. In the framework of our pluridisciplinary consultation, fractionated conformal radiotherapy (FRT) was indicated at a low dose; 20 Gy in 10 fractions of 2 Gy over 12 days were delivered. Clinical response was complete 3 months after FRT. Radiological response was subtotal 6 months after FRT. Two years later, the patient is well
Autophagy inhibition cooperates with erlotinib to induce glioblastoma cell death.
International audienceGliomas are the most common malignant primary brain tumors in adults. The median survival never exceeds 12 months, owing to inherent resistance to both radio and chemotherapies. Epidermal Growth Factor Receptor (EGFR) is amplified, overexpressed, and/or mutated in glioblastomas (GBM), making it a rational for therapy. Erlotinib, an EGFR kinase inhibitor is strongly associated with clinical response in several cancers. Inhibition of cell proliferation and induction of apoptosis by erlotinib were investigated in U87-MG and DBTRG-05MG, two human glioblastoma cell lines. The expression of several apoptosis-related proteins was investigated in these cell lines and in tumoral tissue from glioblastomas. Both cell lines expressed wild-type EGFR but were deficient for PTEN. Erlotinib induced a marked accumulation of the BIM protein, but the activation of caspase-3 machinery was missing, regardless of the decrease in XIAP. Moreover, in U87-MG, erlotinib promoted accumulation of αB-crystallin a small heat shock protein capable to impair caspase activation. DBTRG-05MG was found deficient for procaspase 3 and constitutively overexpressed αB-crystallin. Similarly, deficiencies in PTEN and procaspase 3 were constantly found in samples from glioblastoma samples, while αB-crystallin expression was inconsistent. In cell lines, high concentrations of erlotinib induced cell death through a caspase independent process and an autophagic process was evidenced in U87-MG. Inhibition of autophagy induced a marked increase in the death-inducing activity of erlotinib. These results confirm that glioblastoma cell lines exhibit several anti-apoptotic mechanisms, and underline that EGFR targeted therapy must be associated to other inhibitors to achieve an antitumoral effect