Elodie Vauleon

Comparison of tumor response by Response Evaluation Criteria in Solid Tumors (RECIST) and modified RECIST in patients treated with sorafenib for hepatocellular carcinoma

A significant improvement in overall survival (OS) was demonstrated in patients with advanced hepatocellular carcinoma (HCC) who received sorafenib (Sor) in the Sorafenib HCC Assessment Randomized Protocol (SHARP) study, in contrast to a response rate (RR) of 2% assessed according to Response Evaluation Criteria in Solid Tumors (RECIST). Modified RECIST (mRECIST) were developed to assess the response in patients with HCC, based on measurement of viable tumor with arterial enhancement on a computed tomography (CT) scan. In the current study, mRECIST were evaluated and were compared with RECIST in patients who received Sor for advanced HCC.

DNA methylation in glioblastoma: impact on gene expression and clinical outcome

BackgroundChanges in promoter DNA methylation pattern of genes involved in key biological pathways have been reported in glioblastoma. Genome-wide assessments of DNA methylation levels are now required to decipher the epigenetic events involved in the aggressive phenotype of glioblastoma, and to guide new treatment strategies.ResultsWe performed a whole-genome integrative analysis of methylation and gene expression profiles in 40 newly diagnosed glioblastoma patients. We also screened for associations between the level of methylation of CpG sites and overall survival in a cohort of 50 patients uniformly treated by surgery, radiotherapy and chemotherapy with concomitant and adjuvant temozolomide (STUPP protocol). The methylation analysis identified 616 CpG sites differentially methylated between glioblastoma and control brain, a quarter of which was differentially expressed in a concordant way. Thirteen of the genes with concordant CpG sites displayed an inverse correlation between promoter methylation and expression level in glioblastomas: B3GNT5, FABP7, ZNF217, BST2, OAS1, SLC13A5, GSTM5, ME1, UBXD3, TSPYL5, FAAH, C7orf13, and C3orf14. Survival analysis identified six CpG sites associated with overall survival. SOX10 promoter methylation status (two CpG sites) stratified patients similarly to MGMT status, but with a higher Area Under the Curve (0.78 vs. 0.71, p- value < 5e-04). The methylation status of the FNDC3B, TBX3, DGKI, and FSD1 promoters identified patients with MGMT-methylated tumors that did not respond to STUPP treatment (p- value < 1e-04).ConclusionsThis study provides the first genome-wide integrative analysis of DNA methylation and gene expression profiles obtained from the same GBM cohort. We also present a methylome-based survival analysis for one of the largest uniformly treated GBM cohort ever studied, for more than 27,000 CpG sites. We have identified genes whose expression may be tightly regulated by epigenetic mechanisms and markers that may guide treatment decisions.

Distinct effects of human glioblastoma immunoregulatory molecules programmed cell death ligand-1 (PDL-1) and indoleamine 2,3-dioxygenase (IDO) on tumour-specific T cell functions.

Immunotherapy is a promising new treatment for patients suffering from glioma, in particular glioblastoma multiforme (GBM). However, tumour cells use different mechanisms to escape the immune responses induced by the treatment. As many other tumours, gliomas express or secrete several immunosuppressive molecules that regulate immune cell functions. In this study, we first analysed FasL, HLA-G, IDO, PDL-1 and TGF-beta1, -beta2 and -beta3 expression by transcriptomic microarray analysis in a series of 20 GBM samples and found respectively 15%, 60%, 85%, 30%, 70%, 80% and 35% of positive specimens. mRNA expression was then confirmed in 10 GBM primary cell lines and 2 immortalised cell lines U251 and U87MG. Furthermore, the protein expression of PDL-1, IDO activity and TGF-beta2 secretion were found on most of the untreated GBM primary cell lines. Remarkably, treatment with IFN-gamma increased the PDL-1 cell surface expression and the IDO activity, but reduced the TGF-beta2 secretion of GBM cell lines. We finally analysed the immunosuppressive effects of IDO, PDL-1 and TGF-beta1-3 by measuring IFN-gamma production and cell cytotoxicity activity of tumour antigen-specific T cells. PDL-1 partially affected the IFN-gamma production of antigen-specific T cells in response to GBM primary cell lines, and IDO inhibited lymphocyte proliferation induced by lectins. None of these molecules directly affected the T cell cytotoxicity function. Due to the functional role of PDL-1 and IDO molecules expressed by GBM cells, one could expect that blocking these molecules in the immunotherapy strategies would reinforce the efficiency of these treatments of GBM patients.

Contrast enhancement in 1p/19q-codeleted anaplastic oligodendrogliomas is associated with 9p loss, genomic instability, and angiogenic gene expression

BACKGROUND The aim of this study was to correlate MRI features and molecular characteristics in anaplastic oligodendrogliomas (AOs). METHODS The MRI characteristics of 50 AO patients enrolled in the French national network for high-grade oligodendroglial tumors were analyzed. The genomic profiles and IDH mutational statuses were assessed using high-resolution single-nucleotide polymorphism arrays and direct sequencing, respectively. The gene expression profiles of 25 1p/19q-codeleted AOs were studied on Affymetrix expression arrays. RESULTS Most of the cases were frontal lobe contrast-enhanced tumors (52%), but the radiological presentations of these cases were heterogeneous, ranging from low-grade glioma-like aspects (26%) to glioblastoma-like aspects (22%). The 1p/19q codeletion (n = 39) was associated with locations in the frontal lobe (P = .001), with heterogeneous intratumoral signal intensities (P = .003) and with no or nonmeasurable contrast enhancements (P = .01). The IDH wild-type AOs (n = 7) more frequently displayed ringlike contrast enhancements (P = .03) and were more frequently located outside of the frontal lobe (P = .01). However, no specific imaging pattern could be identified for the 1p/19q-codeleted AO or the IDH-mutated AO. Within the 1p/19q-codeleted AO, the contrast enhancement was associated with larger tumor volumes (P = .001), chromosome 9p loss and CDKN2A loss (P = .006), genomic instability (P = .03), and angiogenesis-related gene expression (P < .001), particularly for vascular endothelial growth factor A and angiopoietin 2. CONCLUSION In AOs, the 1p/19q codeletion and the IDH mutation are associated with preferential (but not with specific) imaging characteristics. Within 1p/19q-codeleted AO, imaging heterogeneity is related to additional molecular alterations, especially chromosome 9p loss, which is associated with contrast enhancement and larger tumor volume.

Human Glioblastoma Stem-Like Cells are More Sensitive to Allogeneic NK and T Cell-Mediated Killing Compared with Serum-Cultured Glioblastoma Cells.

Glioblastoma multiforme (GBM) is the most dramatic primary brain cancer with a very poor prognosis because of inevitable disease recurrence. The median overall survival is less than 1 year after diagnosis. Cancer stem cells have recently been disclosed in GBM. GBM stem‐like cells (GSCs) exhibit resistance to radio/chemotherapeutic treatments and are therefore considered to play an important role in disease recurrence. GSCs are thus appealing targets for new treatments for GBM patients. In this study, we show that GBM cells with stem cell characteristics are resistant to lysis mediated by resting natural killer (NK) cells because of the expression of MHC class I molecules. However, GSCs are killed by lectin‐activated NK cells. Furthermore, in experiments using the therapeutic antibody CetuximAb, we show that GSCs are sensitive to antibody‐mediated cytotoxicity. We confirm the sensitivity of GSC to cytotoxicity carried out by IL2‐activated NK cells and tumor‐specific T cells. More importantly, we show that GSCs are more sensitive to NK and T cell‐mediated lysis relatively to their corresponding serum‐cultured GBM cells obtained from the same initial tumor specimen. Altogether, these results demonstrate the sensitivity of GSC to immune cell cytotoxicity and, therefore, strongly suggest that GSCs are suitable target cells for immunotherapy of GBM patients.

Survival and prognostic factors in a series of adults with medulloblastomas.

OBJECT In this article, the authors report their experience in the management of adult patients with medulloblastoma at their institution to identify prognostic factors important for survival and disease control. METHODS Between 1977 and 2005, 27 patients who were >or=16 years old and had medulloblastoma were treated consecutively. There were 16 women and 11 men with a median age of 21 years (range 16-54 years). Gross-total resection was performed in 21 patients, subtotal (>or=90%) in 2, incomplete in 1, and biopsy in 3 patients. Six patients had the desmoplastic variant, and 21 patients presented with classic medulloblastoma. Staging according to the Chang classification showed 4 patients with tumors invading the brainstem (2 with Stage T3b and 2 with Stage T4), 3 patients with metastases (2 with Stage M2 and 1 with Stage M3), and 1 patient in whom the stage was unknown (Stage MX) who died 10 days postoperatively. Twenty patients were assigned to the standard-risk group and 7 to the high-risk group. All patients except the one whose status was classified as Stage MX underwent craniospinal radiotherapy at our institution. Seven patients received chemotherapy before radiotherapy. RESULTS The 5- and 10-year overall survival rates for the present study were 81 and 62%, respectively. The median overall survival time was 17.7 years. The 5- and 10-year event-free survival rates were 72 and 57%, respectively. The median event-free survival time was 17.9 years. Univariate analysis showed that survival was significantly correlated with sex (women had a better prognosis than men) and M stage (patients without metastases had a better outcome). Patient age, duration of symptoms, Karnofsky Performance Scale score at presentation, hydrocephalus, tumor location, brainstem invasion, extent of resection, histological subtype, preradiotherapy chemotherapy, risk group, and period of presentation were not significant variables. Multivariate analysis identified sex and M stage as well as the period of presentation as independent prognostic factors for overall and event-free survival times. Eleven patients suffered tumor recurrence within a median time of 4.2 years. The posterior fossa was not the most common site of recurrence, and delayed recurrence was not rare. All patients in whom the tumor recurred have died despite aggressive treatments. The median survival time after diagnosis of recurrence was 2.5 years. Questionnaires on quality of life and cognition showed high scores in favor of limited negative effects in the perception of mental and physical health after treatment. The authors observed 1 supposed second malignancy (thyroid carcinoma) and no evidence of pituitary dysfunction. CONCLUSIONS Long-term survival is possible in adults treated for medulloblastoma. Although rare, metastasis seeding at presentation is a poor prognostic factor. The possibility of delayed recurrence necessitates close follow-up of all patients. Tumor recurrences should be treated with aggressive therapies as some patients may have sustained response. Adjuvant chemotherapy should be given to high-risk patients, but its role in reducing recurrences, particularly distant ones, remains unclear in the standard-risk group.

Mechanisms of immunomodulation in human glioblastoma

Glioblastoma multiforme (GBM), WHO grade IV astrocytoma, is the most dramatic primary brain cancer with a very poor prognosis due to inevitable disease recurrence. Less than 10% of GBM patients are still alive 5 years after diagnosis despite a multimodal treatment with surgical resection of the tumor, radiation therapy and chemotherapy. Cellular immunotherapy in gliomas, one of the promising new therapies, has shown convincing results in some patients with induction of antitumor immune responses and prolonged survival. In particular, several patients treated with dendritic cell vaccinations have demonstrated systemic antigen-specific cytotoxicity and intratumor infiltration of cytotoxic T cells. However, this is not always correlated with clinical improvement because GBM cells have multiple mechanisms that lead to suppression of the patients antitumor immune responses. This article will focus on some aspects of the systemic immunosuppression observed in GBM patients as well as the multiple mechanisms of local immunoresistance developed by GBM.

SNP Array Analysis Reveals Novel Genomic Abnormalities Including Copy Neutral Loss of Heterozygosity in Anaplastic Oligodendrogliomas

Anaplastic oligodendrogliomas (AOD) are rare glial tumors in adults with relative homogeneous clinical, radiological and histological features at the time of diagnosis but dramatically various clinical courses. Studies have identified several molecular abnormalities with clinical or biological relevance to AOD (e.g. t(1;19)(q10;p10), IDH1, IDH2, CIC and FUBP1 mutations). To better characterize the clinical and biological behavior of this tumor type, the creation of a national multicentric network, named “Prise en charge des OLigodendrogliomes Anaplasiques (POLA),” has been supported by the Institut National du Cancer (InCA). Newly diagnosed and centrally validated AOD patients and their related biological material (tumor and blood samples) were prospectively included in the POLA clinical database and tissue bank, respectively. At the molecular level, we have conducted a high-resolution single nucleotide polymorphism array analysis, which included 83 patients. Despite a careful central pathological review, AOD have been found to exhibit heterogeneous genomic features. A total of 82% of the tumors exhibited a 1p/19q-co-deletion, while 18% harbor a distinct chromosome pattern. Novel focal abnormalities, including homozygously deleted, amplified and disrupted regions, have been identified. Recurring copy neutral losses of heterozygosity (CNLOH) inducing the modulation of gene expression have also been discovered. CNLOH in the CDKN2A locus was associated with protein silencing in 1/3 of the cases. In addition, FUBP1 homozygous deletion was detected in one case suggesting a putative tumor suppressor role of FUBP1 in AOD. Our study showed that the genomic and pathological analyses of AOD are synergistic in detecting relevant clinical and biological subgroups of AOD.

Integrated multi-omics analysis of oligodendroglial tumours identifies three subgroups of 1p/19q co-deleted gliomas

Oligodendroglial tumours (OT) are a heterogeneous group of gliomas. Three molecular subgroups are currently distinguished on the basis of the IDH mutation and 1p/19q co-deletion. Here we present an integrated analysis of the transcriptome, genome and methylome of 156 OT. Not only does our multi-omics classification match the current classification but also reveals three subgroups within 1p/19q co-deleted tumours, associated with specific expression patterns of nervous system cell types: oligodendrocyte, oligodendrocyte precursor cell (OPC) and neuronal lineage. We confirm the validity of these three subgroups using public datasets. Importantly, the OPC-like group is associated with more aggressive clinical and molecular patterns, including MYC activation. We show that the MYC activation occurs through various alterations, including MYC genomic gain, MAX genomic loss, MYC hypomethylation and microRNA-34b/c down-regulation. In the lower grade glioma TCGA dataset, the OPC-like group is associated with a poorer outcome independently of histological grade. Our study reveals previously unrecognized heterogeneity among 1p/19q co-deleted tumours.

Immune genes are associated with human glioblastoma pathology and patient survival

BackgroundGlioblastoma (GBM) is the most common and lethal primary brain tumor in adults. Several recent transcriptomic studies in GBM have identified different signatures involving immune genes associated with GBM pathology, overall survival (OS) or response to treatment.MethodsIn order to clarify the immune signatures found in GBM, we performed a co-expression network analysis that grouped 791 immune-associated genes (IA genes) in large clusters using a combined dataset of 161 GBM specimens from published databases. We next studied IA genes associated with patient survival using 3 different statistical methods. We then developed a 6-IA gene risk predictor which stratified patients into two groups with statistically significantly different survivals. We validated this risk predictor on two other Affymetrix data series, on a local Agilent data series, and using RT-Q-PCR on a local series of GBM patients treated by standard chemo-radiation therapy.ResultsThe co-expression network analysis of the immune genes disclosed 6 powerful modules identifying innate immune system and natural killer cells, myeloid cells and cytokine signatures. Two of these modules were significantly enriched in genes associated with OS. We also found 108 IA genes linked to the immune system significantly associated with OS in GBM patients. The 6-IA gene risk predictor successfully distinguished two groups of GBM patients with significantly different survival (OS low risk: 22.3 months versus high risk: 7.3 months; p < 0.001). Patients with significantly different OS could even be identified among those with known good prognosis (methylated MGMT promoter-bearing tumor) using Agilent (OS 25 versus 8.1 months; p < 0.01) and RT-PCR (OS 21.8 versus 13.9 months; p < 0.05) technologies. Interestingly, the 6-IA gene risk could also distinguish proneural GBM subtypes.ConclusionsThis study demonstrates the immune signatures found in previous GBM genomic analyses and suggests the involvement of immune cells in GBM biology. The robust 6-IA gene risk predictor should be helpful in establishing prognosis in GBM patients, in particular in those with a proneural GBM subtype, and even in the well-known good prognosis group of patients with methylated MGMT promoter-bearing tumors.