Publications (39)222.85 Total impact
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Article: Molecular guided therapy for advanced pancreatic cancer patients with PI3K activated mutation: vision or illusion?
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ABSTRACT: Despite a modern validated regimen of chemotherapy, advanced pancreatic adenocarcinoma remains the fourth most common cause of cancer-related death worldwide. The phosphoinositide 3-kinase pathway (PI3K)/Akt/mammalian target of rapamycin (mTOR) is a major signaling pathway that may be activated in advanced pancreatic cancer. To highlight the potential interest of this targetable pathway in selected advanced pancreatic cancer patients, we report herein a patient with an activated PI3K mutation who was treated in a phase I trial evaluating a treatment combination including an mTOR inhibitor.OncoTargets and Therapy 01/2013; 6:95-7. · 1.26 Impact Factor -
Article: The challenge to bring personalized cancer medicine from clinical trials into routine clinical practice: the case of the Institut Gustave Roussy.
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ABSTRACT: Research with high throughput technologies has propitiated the segmentation of different types of tumors into very small subgroups characterized by the presence of very rare molecular alterations. The identification of these subgroups and the apparition of new agents targeting these infrequent alterations are already affecting the way in which clinical trials are being conducted with an increased need to identify those patients harboring specific molecular alterations. In this review we describe some of the currently ongoing and future studies at the Institut Gustave Roussy that aim for the identification of potential therapeutic targets for cancer patients with the incorporation of high throughput technologies into daily practice including aCGH, next generation sequencing and the creation of a software that allows for target identification specific for each tumor. The initial intention is to enrich clinical trials with cancer patients carrying certain molecular alterations in order to increase the possibility of demonstrating benefit from a targeted agent. Mid and long term aims are to facilitate and speed up the process of drug development as well as to implement the concept of personalized medicine.Molecular oncology 03/2012; 6(2):204-10. · 4.10 Impact Factor -
Article: Biomarker discovery, development, and implementation in France: a report from the French National Cancer Institute and cooperative groups.
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ABSTRACT: Biomarkers are increasingly changing the medical practice in oncology. One of the major challenges in the field of personalized medicine or biologically adapted therapies is to ensure a rapid and extensive implementation of emerging biomarkers as soon as proof of their medical usefulness is obtained. A special program has been developed in France to facilitate the assessment and use of biomarkers. The French National Cancer Institute has set up a total of 28 laboratories in public hospitals to perform biomarker testing for clinical use. This program is enabling all patients who present with cancer to receive free testing for biomarkers, such as K-Ras, epidermal growth factor receptor, c-Kit, and Braf mutations. Funding for these laboratories comes from the French Ministry of Health. The future of these laboratories includes the development of DNA arrays and multiplex technologies for clinical use. Toward that end, the French National Cancer Institute is financing several large clinical trials that several large clinical trials are currently evaluating the feasibility and medical utility of DNA arrays and next-generation sequencing in the context of academic centers. The programs are being run by cooperative groups.Clinical Cancer Research 03/2012; 18(6):1555-60. · 7.74 Impact Factor -
Article: Skin tumors induced by sorafenib; paradoxic RAS-RAF pathway activation and oncogenic mutations of HRAS, TP53, and TGFBR1.
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ABSTRACT: The emergence of skin tumors in patients treated with sorafenib or with more recent BRAF inhibitors is an intriguing and potentially serious event. We carried out a clinical, pathologic, and molecular study of skin lesions occurring in patients receiving sorafenib. Thirty-one skin lesions from patients receiving sorafenib were characterized clinically and pathologically. DNA extracted from the lesions was screened for mutation hot spots of HRAS, NRAS, KiRAS, TP53, EGFR, BRAF, AKT1, PI3KCA, TGFBR1, and PTEN. Biological effect of sorafenib was studied in vivo in normal skin specimen and in vitro on cultured keratinocytes. We observed a continuous spectrum of lesions: from benign to more inflammatory and proliferative lesions, all seemingly initiated in the hair follicles. Eight oncogenic HRAS, TGFBR1, and TP53 mutations were found in 2 benign lesions, 3 keratoacanthomas (KA) and 3 KA-like squamous cell carcinoma (SCC). Six of them correspond to the typical UV signature. Treatment with sorafenib led to an increased keratinocyte proliferation and a tendency toward increased mitogen-activated protein kinase (MAPK) pathway activation in normal skin. Sorafenib induced BRAF-CRAF dimerization in cultured keratinocytes and activated CRAF with a dose-dependent effect on MAP-kinase pathway activation and on keratinocyte proliferation. Sorafenib induces keratinocyte proliferation in vivo and a time- and dose-dependent activation of the MAP kinase pathway in vitro. It is associated with a spectrum of lesions ranging from benign follicular cystic lesions to KA-like SCC. Additional and potentially preexisting somatic genetic events, like UV-induced mutations, might influence the evolution of benign lesions to more proliferative and malignant tumors.Clinical Cancer Research 11/2011; 18(1):263-72. · 7.74 Impact Factor -
Article: Molecular Characteristics of ERCC1-Negative versus ERCC1-Positive Tumors in Resected NSCLC.
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ABSTRACT: Excision repair cross-complementation group 1 (ERCC1) is a protein involved in repair of DNA platinum adducts and stalled DNA replication forks. We and others have previously shown the influence of ERCC1 expression upon survival rates and benefit of cisplatin-based chemotherapy in patients with resected non-small-cell lung cancer (NSCLC). However, little is known about the molecular characteristics of ERCC1-positive and ERCC1-negative tumors. We took advantage of a cohort of 91 patients with resected NSCLC, for which we had matched frozen and paraffin-embedded samples to explore the comparative molecular portraits of ERCC1-positive and ERCC1-negative tumors of NSCLC. We carried out a global molecular analysis including assessment of ERCC1 expression levels by using both immunohistochemistry (IHC) and quantitative reverse transcriptase PCR (qRT-PCR), genomic instability, global gene and miRNA expression, and sequencing of selected key genes involved in lung carcinogenesis. ERCC1 protein and mRNA expression were significantly correlated. However, we observed several cases with clear discrepancies. We noted that ERCC1-negative tumors had a higher rate of genomic abnormalities versus ERCC1-positive tumors. ERCC1-positive tumors seemed to share a common DNA damage response (DDR) phenotype with the overexpression of seven genes linked to DDR. The miRNA expression analysis identified miR-375 as significantly underexpressed in ERCC1-positive tumors. Our data show inconsistencies in ERCC1 expression between IHC and qRT-PCR readouts. Furthermore, ERCC1 status is not linked to specific mutational patterns or frequencies. Finally, ERCC1-negative tumors have a high rate of genomic aberrations that could consequently influence prognosis in patients with resected NSCLC.Clinical Cancer Research 08/2011; 17(17):5562-72. · 7.74 Impact Factor -
Article: Implications of personalized medicine--perspective from a cancer center.
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ABSTRACT: Three advances are dramatically changing the landscape of oncology. First, hundreds of drugs are available that inhibit targets involved in oncogenesis. Second, efforts to reclassify malignant diseases are expanding the number of orphan molecular diseases. Third, the implementation of high-throughput technologies will allow risk of relapse prediction and drug sensitivity. Patients predicted to relapse will be referred to comprehensive cancer centers where new drugs will be tested. It is anticipated that a high number of small, biology-driven clinical trials will report high sensitivity to targeted agents in rare biologically defined diseases. Drug registration and biomarker analysis needs to be revisited to avoid large phase III trials with control arms. The use of high-throughput technologies will lead to the development of virtual cells. These considerations highlight the need for developing a consortium of comprehensive cancer centers to run clinical trials in rare, molecularly-defined populations, and implement high-throughput technologies for daily practice.Nature Reviews Clinical Oncology 03/2011; 8(3):177-83. · 11.96 Impact Factor -
Article: Atypical teratoid rhabdoid tumor mimicking beta-catenin-positive nodular medulloblastoma.
Acta Neuropathologica 03/2011; 121(3):429-30. · 9.32 Impact Factor -
Article: Identification of soluble candidate biomarkers of therapeutic response to sunitinib in medullary thyroid carcinoma in preclinical models.
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ABSTRACT: Medullary thyroid carcinoma (MTC), an aggressive rare tumor due to activating mutations in the proto-oncogene RET, requires new therapeutic strategies. Sunitinib, a potent inhibitor of RET, VEGF receptor (VEGFR)-1, VEGFR-2, VEGFR-3, and platelet-derived growth factor receptor (PDGFR)α/β, has been reported as clinically effective in some patients with advanced MTC. In this study, we examine molecular mechanisms of action of sunitinib and identify candidate soluble biomarkers of response. Both in vitro and in vivo assays, using the human TT RET(C634W) MTC cell line, were done to assess the activity of sunitinib. Kinetic microarray studies were used to analyze molecular pathways modified by sunitinib and to identify candidate biomarkers that were subsequently investigated in the serum of patients. Sunitinib displayed antiproliferative and antiangiogenic activities and inhibited RET autophosphorylation and activation of downstream signaling pathways. We showed that sunitinib treatment induced major changes in the expression of genes involved in tissue invasion and metastasis including vimentin (VIM), urokinase plasminogen (PLAU), tenascin-C (TN-C), SPARC, and CD44. Analyzing downregulated genes, we identified those encoding secreted proteins and, among them, interleukin (IL)-8 was found to be modulated in the serum of xenografted mice under sunitinib treatment. Furthermore, we demonstrated that metastatic MTC patients presented increased serum levels of IL-8 and TGF-β2. Experimental models confirm the clinical efficacy of sunitinib observed in a few studies. Molecular pathways revealed by genomic signatures underline the impact of sunitinib on tissue invasion. Selected soluble candidate biomarkers could be of value for monitoring sunitinib response in metastatic MTC patients.Clinical Cancer Research 02/2011; 17(7):2044-54. · 7.74 Impact Factor -
Article: Gene expression signature discriminates sporadic from post-radiotherapy-induced thyroid tumors.
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ABSTRACT: Both external and internal exposure to ionizing radiation are strong risk factors for the development of thyroid tumors. Until now, the diagnosis of radiation-induced thyroid tumors has been deduced from a network of arguments taken together with the individual history of radiation exposure. Neither the histological features nor the genetic alterations observed in these tumors have been shown to be specific fingerprints of an exposure to radiation. The aim of our work is to define ionizing radiation-related molecular specificities in a series of secondary thyroid tumors developed in the radiation field of patients treated by radiotherapy. To identify molecular markers that could represent a radiation-induction signature, we compared 25K microarray transcriptome profiles of a learning set of 28 thyroid tumors, which comprised 14 follicular thyroid adenomas (FTA) and 14 papillary thyroid carcinomas (PTC), either sporadic or consecutive to external radiotherapy in childhood. We identified a signature composed of 322 genes which discriminates radiation-induced tumors (FTA and PTC) from their sporadic counterparts. The robustness of this signature was further confirmed by blind case-by-case classification of an independent set of 29 tumors (16 FTA and 13 PTC). After the histology code break by the clinicians, 26/29 tumors were well classified regarding tumor etiology, 1 was undetermined, and 2 were misclassified. Our results help shed light on radiation-induced thyroid carcinogenesis, since specific molecular pathways are deregulated in radiation-induced tumors.Endocrine Related Cancer 01/2011; 18(1):193-206. · 4.36 Impact Factor -
Article: Persistent disease and recurrence in differentiated thyroid cancer patients with undetectable postoperative stimulated thyroglobulin level.
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ABSTRACT: (131)I is given in differentiated thyroid cancer (DTC) without taking into account thyroglobulin (Tg) levels at the time of ablation, whereas 6-18 months later it is a major criterion for cure. This single-center retrospective study assessed the frequency and risk factors for persistent disease on postablation whole body scan (WBS) and postoperative neck ultrasonography (n-US) and for recurrent disease during the subsequent follow-up, in patients with DTC and undetectable TSH-stimulated Tg level (TSH-Tg) in the absence of Tg antibodies (TgAb) at the time of ablation. Among 1031 patients ablated, 242 (23%) consecutive patients were included. Persistent disease occurred in eight cases (3%) (seven abnormal WBS and one abnormal n-US), all with initial neck lymph node metastases (N1). N1 was a major risk factor for persistent disease. Among 203 patients with normal WBS and a follow-up over 6 months, TSH-Tg 6-18 months after ablation was undetectable in the absence of TgAb in 173 patients, undetectable with TgAb in 1 patient and equal to 1.2 ng/ml in 1 patient. n-US was normal in 152 patients and falsely positive in 3 patients. After a mean follow-up of 4 years, recurrence occurred in two cases (1%), both with aggressive histological variants. The only risk factor for recurrence was an aggressive histological variant (P = 0.03). In conclusion, undetectable postoperative TSH-Tg in the absence of TgAb at the time of ablation is frequent. In these patients, repeating TSH-Tg 6-18 months after ablation is not useful. (131)I ablation could be avoided in the absence of N1 and aggressive histological variant.Endocrine Related Cancer 12/2010; 18(2):R29-40. · 4.36 Impact Factor -
Article: Differential gene expression profiles of invasive and non-invasive non-functioning pituitary adenomas based on microarray analysis.
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ABSTRACT: Non-functioning pituitary adenomas (NFPAs) may be locally invasive. Markers of invasiveness are needed to guide patient management and particularly the use of adjuvant radiotherapy. To examine whether invasive NFPAs display a specific gene expression profile relative to non-invasive tumors, we selected 40 NFPAs (38 of the gonadotroph type) and classified them as invasive (n=22) or non-invasive (n=18) on the basis of magnetic resonance imaging and surgical findings. We then performed pangenomic analysis with the 44k Agilent human whole genome expression oligonucleotide microarray in order to identify genes with differential expression between invasive and non-invasive NFPAs. Candidate genes were then tested in qRT-PCR. Prediction class analysis showed that the expression of 346 genes differed between invasive and non-invasive NFPAs (P<0.001), of which 233 genes were up-regulated and 113 genes were down-regulated in invasive tumors. On the basis of Ingenuity networks and the degree of up- or down-regulation in invasive versus non-invasive tumors, 35 genes were selected for expression quantification by qRT-PCR. Overexpression of only four genes was confirmed, namely IGFBP5 (P=0.02), MYO5A (P=0.04), FLT3 (P=0.01), and NFE2L1 (P=0.02). At the protein level, only myosin 5A (MYO5A) immunostaining was stronger in invasive than in non-invasive NFPAs. Molecular signature allows to differentiate 'grossly' invasive from non-invasive NFPAs. The product of one of these genes, MYO5A, may be a useful marker of tumor invasiveness.Endocrine Related Cancer 03/2010; 17(2):361-71. · 4.36 Impact Factor -
Article: Portrait of ependymoma recurrence in children: biomarkers of tumor progression identified by dual-color microarray-based gene expression analysis.
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ABSTRACT: Children with ependymoma may experience a relapse in up to 50% of cases depending on the extent of resection. Key biological events associated with recurrence are unknown. To discover the biology behind the recurrence of ependymomas, we performed CGHarray and a dual-color gene expression microarray analysis of 17 tumors at diagnosis co-hybridized with the corresponding 27 first or subsequent relapses from the same patient. As treatment and location had only limited influence on specific gene expression changes at relapse, we established a common signature for relapse. Eighty-seven genes showed an absolute fold change ≥2 in at least 50% of relapses and were defined as the gene expression signature of ependymoma recurrence. The most frequently upregulated genes are involved in the kinetochore (ASPM, KIF11) or in neural development (CD133, Wnt and Notch pathways). Metallothionein (MT) genes were downregulated in up to 80% of the recurrences. Quantitative PCR for ASPM, KIF11 and MT3 plus immunohistochemistry for ASPM and MT3 confirmed the microarray results. Immunohistochemistry on an independent series of 24 tumor pairs at diagnosis and at relapse confirmed the decrease of MT3 expression at recurrence in 17/24 tumor pairs (p = 0.002). Conversely, ASPM expression was more frequently positive at relapse (87.5% vs 37.5%, p = 0.03). Loss or deletion of the MT genes cluster was never observed at relapse. Promoter sequencing after bisulfite treatment of DNA from primary tumors and recurrences as well as treatment of short-term ependymoma cells cultures with a demethylating agent showed that methylation was not involved in MT3 downregulation. However, in vitro treatment with a histone deacetylase inhibitor or zinc restored MT3 expression. The most frequent molecular events associated with ependymoma recurrence were over-expression of kinetochore proteins and down-regulation of metallothioneins. Metallothionein-3 expression is epigenetically controlled and can be restored in vitro by histone deacetylase inhibitors.PLoS ONE 01/2010; 5(9):e12932. · 4.09 Impact Factor -
Article: Genomic aberrations in lung adenocarcinoma in never smokers.
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ABSTRACT: Lung cancer in never smokers would rank as the seventh most common cause of cancer death worldwide. We performed high-resolution array comparative genomic hybridization analysis of lung adenocarcinoma in sixty never smokers and identified fourteen new minimal common regions (MCR) of gain or loss, of which five contained a single gene (MOCS2, NSUN3, KHDRBS2, SNTG1 and ST18). One larger MCR of gain contained NSD1. One focal amplification and nine gains contained FUS. NSD1 and FUS are oncogenes hitherto not known to be associated with lung cancer. FISH showed that the amplicon containing FUS was joined to the next telomeric amplicon at 16p11.2. FUS was over-expressed in 10 tumors with gain of 16p11.2 compared to 30 tumors without that gain. Other cancer genes present in aberrations included ARNT, BCL9, CDK4, CDKN2B, EGFR, ERBB2, MDM2, MDM4, MET, MYC and KRAS. Unsupervised hierarchical clustering with adjustment for false-discovery rate revealed clusters differing by the level and pattern of aberrations and displaying particular tumor characteristics. One cluster was strongly associated with gain of MYC. Another cluster was characterized by extensive losses containing tumor suppressor genes of which RB1 and WRN. Tumors in that cluster frequently harbored a central scar-like fibrosis. A third cluster was associated with gains on 7p and 7q, containing ETV1 and BRAF, and displayed the highest rate of EGFR mutations. SNP array analysis validated copy-number aberrations and revealed that RB1 and WRN were altered by recurrent copy-neutral loss of heterozygosity. The present study has uncovered new aberrations containing cancer genes. The oncogene FUS is a candidate gene in the 16p region that is frequently gained in never smokers. Multiple genetic pathways defined by gains of MYC, deletions of RB1 and WRN or gains on 7p and 7q are involved in lung adenocarcinoma in never smokers.PLoS ONE 01/2010; 5(12):e15145. · 4.09 Impact Factor -
Article: Aggressive inherited and sporadic medullary thyroid carcinomas display similar oncogenic pathways.
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ABSTRACT: RET oncogene mutations are found in familial medullary thyroid carcinomas (MTC) and in one-third of sporadic cases. Oncogenic mechanisms involved in non-RET mutated sporadic MTC remain unclear. To study alterations associated with the development of both inherited and sporadic MTC, pangenomic DNA microarrays were used to analyze the transcriptome of 13 MTCs (four familial and nine sporadic). By using an ANOVA test, a list of 173 gene sequences with at least a twofold change expression was obtained. A subset of differentially expressed genes was controlled by real-time quantitative PCR and immunohistochemistry on a larger collection of MTCs. The expression pattern of those genes allowed us to distinguish two groups of sporadic tumors. The first group displays an expression profile similar to that expressed by inherited RET634 tumors. The second presents an expression profile close to that displayed by inherited RET918 tumors and includes tumors from patients with distant metastases. It is characterized by the overexpression of genes involved in proliferation and invasion (PTN, ESM1, and CEACAM6) or matrix remodeling (COL1A1, COL1A2, and FAP). Interestingly, RET918 tumors showed overexpression of the PTN gene, encoding pleiotrophin, a protein associated with metastasis. Using a MTC cell line, silencing of RET induced the inhibition of PTN gene expression. Overall, our results suggest that familial MTC and sporadic MTC could activate similar oncogenic pathways.Endocrine Related Cancer 09/2009; 16(4):1261-72. · 4.36 Impact Factor -
Article: Intracellular expression of reactive oxygen species-generating NADPH oxidase NOX4 in normal and cancer thyroid tissues.
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ABSTRACT: NADPH oxidase 4 (NOX4) belongs to the NOX family that generates reactive oxygen species (ROS). Function and tissue distribution of NOX4 have not yet been entirely clarified. To date, in the thyroid gland, only DUOX1/2 NOX systems have been described. NOX4 mRNA expression, as shown by real-time PCR, was present in normal thyroid tissue, regulated by TSH and significantly increased in differentiated cancer tissues. TSH increased the protein level of NOX4 in human thyroid primary culture and NOX4-dependent ROS generation. NOX4 immunostaining was detected in normal and pathologic thyroid tissues. In normal thyroid tissue, staining was heterogeneous and mostly found in activated columnar thyrocytes but absent in quiescent flat cells. Papillary and follicular thyroid carcinomas displayed more homogeneous staining. The p22(phox) protein that forms a heterodimeric enzyme complex with NOX4 displayed an identical cellular expression pattern and was also positively regulated by TSH. ROS may have various biological effects, depending on the site of production. Intracellular NOX4-p22(phox) localization suggests a role in cytoplasmic redox signaling, in contrast to the DUOX localization at the apical membrane that corresponds to an extracellular H(2)O(2) production. Increased NOX4-p22(phox) in cancer might be related to a higher proliferation rate and tumor progression but a role in the development of tumors has to be further studied and established in the future.Endocrine Related Cancer 09/2009; 17(1):27-37. · 4.36 Impact Factor -
Article: Candidate genes on chromosome 9q33-34 involved in the progression of childhood ependymomas.
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ABSTRACT: The molecular pathogenesis of pediatric ependymoma remains unclear. Our study was designed to identify genetic changes implicated in ependymoma progression. We characterized 59 ependymoma samples (33 at diagnosis and 26 at relapse) using array-comparative genomic hybridization (aCGH). Specific chromosomal imbalances were confirmed by fluorescent in situ hybridization, and candidate genes were assessed by real-time quantitative polymerase chain reaction (qPCR), immunohistochemistry, sequencing, and in vitro functional studies. aCGH analysis revealed a significant increase in genomic imbalances on relapse compared with diagnosis, such as gain of 9qter and 1q (54% v 21% and 12% v 0%, respectively) and loss of 6q (27% v 6%). Supervised tumor classification showed that gain of 9qter was associated with tumor recurrence, age older than 3 years, and posterior fossa location. Using a candidate-gene strategy, we found an overexpression of two potential oncogenes at the locus 9qter: Tenascin-C and Notch1. Moreover, Notch pathway analysis (qPCR) revealed overexpression of Notch ligands, receptors, and target genes (Hes-1, Hey2, and c-Myc), and downregulation of Notch repressor Fbxw7. We confirmed by immunohistochemistry the overexpression of Tenascin-C and Hes-1. We detected Notch1 missense mutations in 8.3% of the tumors (only in the posterior fossa location and in case of 9q33-34 gain). Furthermore, inhibition of Notch pathway with a gamma-secretase inhibitor impaired the growth of ependymoma stem cell cultures. The activation of the Notch pathway and Tenascin-C seem to be important events in ependymoma progression and may represent future targets for therapy. We report, to our knowledge for the first time, recurrent oncogenic mutations in pediatric posterior fossa ependymomas.Journal of Clinical Oncology 04/2009; 27(11):1884-92. · 18.37 Impact Factor -
Article: Fine-needle aspiration for nucleic acid-ased molecular analyses in breast cancer.
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ABSTRACT: With the widespread development of genomic analysis, an accurate and quick method for obtaining high-quality nucleic acids is needed. The objective of the current study was to evaluate the quality and potential use of material obtained from fine-needle aspiration cytology (FNAC). Ultrasound- or palpation-guided FNAC was performed in 124 consecutive patients who had nodular breast lesions. The authors evaluated the amount of messenger RNA (mRNA) obtained, its quality through the RNA Integrity (RIN) score, and the factors that influenced both. For malignant lesions, the authors attempted to correlate estrogen receptor 1 (ESR1) and HER-2 (c-erb-B2) mRNA expression measured by real-time quantitative polymerase chain reaction with estrogen receptor and HER-2 detection obtained by immunohistochemistry (IHC) and/or fluorescent in situ hybridization (FISH) on the surgical specimen. The amount of mRNA obtained was >1 microg in 89.5% of 124 samples (43 benign lesions and 81 adenocarcinomas). Overall, 59.3% of samples yielded >1 microg RNA with a RIN score >6. The most significant predictors of quality and quantity of mRNA were the cytopathologist who sampled the tumors and a diagnosis of cancer versus benign lesion. The median ESR1 expression level, which was expressed as the polymerase chain reaction cycle threshold (CT) level minus the average 18S value (dct), was 17.7 dct in patients with estrogen receptor-negative tumors and 11.1 dct in patients with estrogen receptor-positive tumors. The median HER-2 expression level was 15.1 dct in patients with HER-2-negative tumors and 10.7 dct in patients with HER-2-positive tumors. mRNA expression was concordant with the IHC/FISH evaluation in 90.3% of patients for estrogen receptor status and in 98.5% of patients for HER-2 status. In 70% of cases, FNAC of breast lesions in well trained hands allowed the extraction of mRNA suitable for gene expression analysis.Cancer 02/2009; 117(1):32-9. · 4.77 Impact Factor -
Article: Exonic expression profiling of breast cancer and benign lesions: a retrospective analysis.
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ABSTRACT: Gene-expression arrays have generated molecular predictors of relapse and drug sensitivity in breast cancer. We aimed to identify exons differently expressed in malignant and benign breast lesions and to generate a molecular classifier for breast-cancer diagnosis. 165 breast samples were obtained by fine-needle aspiration. Complementary DNA was hybridised on splice array. A nearest centroid prediction rule was developed to classify lesions as malignant or benign on a training set, and its performance was assessed on an independent validation set. A two-way ANOVA model identified probe sets with differential expression in malignant and benign lesions while adjusting for scan dates. 120 breast cancers and 45 benign lesions were included in the study. A molecular classifier for breast-cancer diagnosis with 1228 probe sets was generated from the training set (n=94). This signature accurately classified all samples (100% accuracy, 95% CI 96-100%). In the validation set (n=71), the molecular predictor accurately classified 68 of 71 tumours (96%, 88-99%). When the 165 samples were taken into account, 37 858 exon probe sets (5.4%) and 3733 genes (7.0%) were differently expressed in malignant and benign lesions (threshold: adjusted p<0.05). Genes involved in spliceosome assembly were significantly overexpressed in malignant disease (permutation p=0.002). In the same population of 165 samples, 956 exon probe sets presented both higher intensity and higher splice index in breast cancer than in benign lesions, although located on unchanged genes. Many exons are differently expressed by breast cancer and benign lesions, and alternative transcripts contribute to the molecular characteristics of breast malignancy. Development of molecular classifiers for breast-cancer diagnosis with fine-needle aspiration should be possible.The lancet oncology 02/2009; 10(4):381-90. · 14.47 Impact Factor -
Article: Mutational status of EGFR, BRAF, PI3KCA and JAK2 genes in endocrine tumors.
International Journal of Cancer 10/2008; 124(3):751-3. · 5.44 Impact Factor -
Article: EGFR tyrosine kinase inhibition radiosensitizes and induces apoptosis in malignant glioma and childhood ependymoma xenografts.
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ABSTRACT: Malignant gliomas and childhood ependymomas have a high rate of treatment failure. Epidermal growth factor receptor (EGFR) activation has been implicated in the tumorigenesis and radioresistance of many cancers, including brain tumors. Therefore, combining EGFR targeting with irradiation is a potentially attractive therapeutic option. We evaluated the tyrosine kinase inhibitor gefitinib for its antitumor activity and potential to radio-sensitize in vivo in two xenograft models: an EGFR amplified glioma and an EGFR expressing ependymoma, both derived from primary tumors. When administered at 100 mg/kg for 5 consecutive days, gefitinib-induced partial tumor regression in all treated EGFR amplified IGRG88 glioma xenografts. The addition of 1 Gy of irradiation prior to gefitinib administration resulted in 5 complete and 4 partial regressions for the 9 treated tumors as well as a significant tumor growth delay of 33 days for the combined treatment compared to 19 days for each therapy alone, suggesting additive antitumor activity. Tumor regression was associated with inhibition of AKT and MAPK pathways by gefitinib. In contrast, the ependymoma IGREP83 was sensitive to irradiation, but remained resistant to gefitinib. Combined treatment was associated with inhibition of radiation-induced MAPK phosphorylation and significant induction of apoptotic cell death though radiation-induced AKT phosphorylation was maintained. Depending on the scheduling of both therapies, a trend towards superior antitumor activity was observed with combined treatment. Thus, EGFR targeting through tyrosine kinase inhibition appears to be a promising new approach in the treatment of EGFR-driven glioma, particularly in combination with radiation therapy.International Journal of Cancer 08/2008; 123(1):209-16. · 5.44 Impact Factor
Top co-authors
Top Journals
Institutions
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2005–2007
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Institut de Cancérologie Gustave Roussy
Villejuif, Ile-de-France, France -
Sapienza University of Rome
Roma, Latium, Italy
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2002–2005
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Universita' degli Studi "Magna Græcia" di Catanzaro
Catanzaro, Calabria, Italy
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2004
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French National Centre for Scientific Research
Lyon, Rhone-Alpes, France
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