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Luc Xerri

Publications and source records attributed to Luc Xerri.

At least 19 recordsLinked to original sources
PubMed2006

FGFR1 and WT1 are markers of human prostate cancer progression.

BACKGROUND: Androgen-independent prostate adenocarcinomas are responsible for about 6% of overall cancer deaths in men. METHODS: We used DNA microarrays to identify genes related to the transition between androgen-dependent and androgen-independent stages in the LuCaP 23.1 xenograft model of prostate adenocarcinoma. The expression of the proteins encoded by these genes was then assessed by immunohistochemistry on tissue microarrays (TMA) including human prostate carcinoma samples issued from 85 patients who had undergone radical prostatectomy. RESULTS: FGFR1, TACC1 and WT1 gene expression levels were associated with the androgen-independent stage in xenografts and human prostate carcinoma samples. MART1 protein expression was correlated with pT2 tumor stages. CONCLUSION: Our results suggest that each of these four genes may play a role, or at least reflect a stage of prostate carcinoma growth/development/progression.

Adenocarcinoma↗
PubMed2006

Prognosis and gene expression profiling of 20q13-amplified breast cancers.

PURPOSE: Amplification of chromosomal region 20q13 occurs in breast cancer but remains poorly characterized. EXPERIMENTAL DESIGN: To establish the frequency of 20q13 amplification and select the amplified cases to be studied, we used fluorescence in situ hybridization of bacterial artificial chromosome probes for three 20q13 loci (MYBL2, STK6, ZNF217) on sections of tissue microarrays containing 466 primary carcinoma samples. We used Affymetryx whole-genome DNA microarrays to establish the gene expression profiles of 20q13-amplified tumors and quantitative reverse transcription-PCR to validate the results. RESULTS: We found 36 (8%) 20q13-amplified samples. They were distributed in two types: type 1 tumors showed ZNF217 amplification only, whereas type 2 tumors showed amplification at two or three loci. Examination of the histoclinical features of the amplified tumors showed two strikingly opposite data. First, type 1 tumors were more frequently lymph node-negative tumors but were paradoxically associated with a poor prognosis. Second, type 2 tumors were more frequently lymph node-positive tumors but were paradoxically associated with a good prognosis. Type 1 and type 2 showed different gene expression profiles. No 20q13 gene could be associated with type 1 amplification, whereas several 20q13 genes were overexpressed in type 2 tumors. CONCLUSIONS: Our results suggest that amplified tumors of types 1 and 2 are two distinct entities resulting from two different mechanisms and associated to different prognosis.

Breast Neoplasms↗
PubMed2006

[The consortium of Biological Resource Centres (BRC) and tumour cell and tissue banks in the Marseilles metropolitan area].

The goal of this presentation is to describe current and future aspects of the operations within the consortium of Biological Resource Centres (BRC) and Tumour cell and tissue banks of the Marseilles metropolitan area. The consortium was created in year 2001, through the association of several tissue and cell banks that were operating for many years in Marseilles. Existing collections are not exclusively collections of tumour cells or tissues; however, the two tumour cell and tissue banks located at the Regional Cancer Research Centre and at the University Hospital account for a very significant proportion of the collections. Our collective work leads to the recognition and funding of the consortium by Inserm, through the "Collections 2003" grant. The consortium objectives are to define a common scientific strategy, to share professional practices in the logistics and database management of the banks, to establish a quality management program, and to build a common catalogue that describes existing biological resources. Through these efforts, the ultimate goal is to adopt rules that define BRC, as defined by the Organization for Economic Co-operation and Development (OECD).

France↗
PubMed2005

"Sugar" tumor of the pancreas: a rare entity that is diagnosable on preoperative fine-needle biopsies.

This study is the second to report a pancreatic "sugar" tumor (ST) case. This ST was incidentally discovered in a 31-year-old woman using computed tomography scan (CT scan) for work-up of a hepatic focal nodular hyperplasia. Both CT scan and endoluminal ultrasonography (EUS) features evoked a 15-mm large benign endocrine tumor. Pathological examination of EUS-guided fine-needle aspiration biopsies could not confirm this diagnosis. Laparoscopic corporeo-caudal pancreatectomy was performed. The tumor was intrapancreatic, well circumscribed, and organized in sheets of epithelioid cells. The tumor cells expressed HMB-45 but did not express epithelial or endocrine immunohistochemical markers. These histophenotypic features are those of an extra pulmonary ST, which belong to the PEComa family of tumors. Retrospective examination of preoperative biopsies evidenced the same histophenotypic features. This observation highlights that STs should be considered in preoperative differential diagnosis of pancreas tumors, since they may be treated by limited surgical resection.

Adult↗
PubMed2005

Gene expression profiling identifies molecular subtypes of inflammatory breast cancer.

Breast cancer is a heterogeneous disease. Comprehensive gene expression profiles obtained using DNA microarrays have revealed previously indistinguishable subtypes of noninflammatory breast cancer (NIBC) related to different features of mammary epithelial biology and significantly associated with survival. Inflammatory breast cancer (IBC) is a rare, particular, and aggressive form of disease. Here we have investigated whether the five molecular subtypes described for NIBC (luminal A and B, basal, ERBB2 overexpressing, and normal breast-like) were also present in IBC. We monitored the RNA expression of approximately 8,000 genes in 83 breast tissue samples including 37 IBC, 44 NIBC, and 2 normal breast samples. Hierarchical clustering identified the five subtypes of breast cancer in both NIBC and IBC samples. These subtypes were highly similar to those defined in previous studies and associated with similar histoclinical features. The robustness of this classification was confirmed by the use of both alternative gene set and analysis method, and the results were corroborated at the protein level. Furthermore, we show that the differences in gene expression between NIBC and IBC and between IBC with and without pathologic complete response that we have recently reported persist in each subtype. Our results show that the expression signatures defining molecular subtypes of NIBC are also present in IBC. Obtained using different patient series and different microarray platforms, they reinforce confidence in the expression-based molecular taxonomy but also give evidence for its universality in breast cancer, independently of a specific clinical form.

Adenocarcinoma↗
PubMed2005

Typical medullary breast carcinomas have a basal/myoepithelial phenotype.

Medullary breast cancer (MBC) is a rare, diagnostically difficult, pathological subtype. Despite being high grade, it has a good prognosis. MBC patients have an excess of BRCA1 germ-line mutation and reliable identification of MBC could help to identify patients at risk of carrying germline BRCA1 mutations or in whom chemotherapy could be avoided. The aim of this study was therefore to improve diagnosis by establishing an MBC protein expression profile using immunohistochemistry (IHC) on tissue-microarrays (TMA). Using a series of 779 breast carcinomas ('EC' set), diagnosed initially as MBC, a double-reading session was carried out by several pathologists on all of the histological material to establish the diagnosis as firmly as possible using a 'medullary score'. Only MBCs with high scores, i.e. typical MBC (TMBC) (n=44) and non-TMBC grade III with no or low scores (n=160), were included in the IHC study. To validate the results obtained on this first set, a control series of TMBC (n=17) and non-MBC grade III cases (n=140) ('IPC' set) was studied. The expression of 18 proteins was studied in the 61 TMBCs and 300 grade III cases from the two sets. The global intra-observer concordance of the first reading for the diagnosis of TMBC was 94%, with almost perfect kappa (kappa) of 0.815. TMBC was characterized by a high degree of basal/myoepithelial differentiation. In multivariate analysis with logistic regression, TMBC was defined by the association of P-cadherin (R=2.29), MIB1 > 50 (R=3.80), ERBB2 negativity (R=2.24) and p53 positivity (RR=1.45).

Breast Neoplasms↗
PubMed2005

[Plasmablastic lymphoma in a patient with HIV infection: an unusual case located in the skin].

We report the case of a plasmablastic lymphoma involving the skin in a 45 year-old HIV-positive patient. Plasmablastic lymphoma was first described in 1997 and is considered to be a diffuse large B-cell lymphoma with a unique immunophenotype and a predilection for the oral cavity. In this case, the tumor was revealed by multiple purple cutaneous nodules predominantly localized on the trunk and proximal parts of the limbs. A skin biopsy led to the diagnosis of plasmablastic lymphoma in view of the presence of a dense nodular infiltrate invading the dermis and subcutaneous fat composed of large cells that expressed neither the leucocyte common antigen nor the B- and T-cell antigens CD20 and CD3, but which showed a strong immunostaining with plasma cell marker VS38c. Most of the cells expressed Kappa light chain of immunoglobulins, they did not express Lambda light chain. In situ hybridization with EBER probe revealed detection of Epstein Barr virus in about 15 % of tumor cells. The clinical course was aggressive and rapidly fatal. Despite one cycle chemotherapy the patient died four months after presentation. HIV-associated plasmablastic lymphoma is a poor prognosis malignancy that may resist typing due to the lack of expression of commonly used lymphoid markers.

Fatal Outcome↗
PubMed2005

[A tumor-like lymphocytis mastitis].

A 44-year-old woman presenting with an inflammatory and palpable firm breast lump underwent surgical excision. Intraoperative frozen section analysis showed an extensive lesion consisting of ducts with intraluminal "necrosis". In addition, a very dense stromal inflammation was observed around these ducts, suggesting an invasive ductal carcinoma with predominant intraductal proliferation. However, on paraffin sections, epithelial cells close to the lymphocytic infiltrate were rare, subatrophic, without any neoplastic feature. The density and architecture of the lymphocytic infiltrate mimicked a breast lymphoma. However, immunochemistry and molecular biology investigation favored the diagnosis of a tumor-like lymphocytic mastitis. Although extremely rare, this particular form of lymphocytic mastitis, a diagnostic pitfall particularly during peroperative examination, should be recognized by pathologists.

Adult↗
PubMed2005

Identification of TCL1A as an immunohistochemical marker of adverse outcome in diffuse large B-cell lymphomas.

We used a combination of DNA-microarray and tissue-microarray (TMA) analyses to identify markers that could be routinely used to predict the outcome of diffuse large-B-cell lymphoma (DLCL) patients. Gene expression profiling was performed using DNA-microarrays on 52 tumour biopsy samples [31 DLCL and 21 follicular lymphomas (FL)] from 48 patients (28 DLCL and 20 FL). T-cell leukemia/lymphoma-1A (TCL1A) mRNA overexpression was correlated with relapse in DLCL patients. TMA analysis was applied on a distinct series of 36 formalin-fixed, paraffin-embedded DLCL samples and showed that TCL1A immunoexpression was correlated with either higher relapse (p=0.02) or lower 5-year overall survival (p=0.009) rates. Moreover, the prognostic value of TCL1A was independent from IPI in our series. Our data suggest that TCL1A immunodetection is an independent marker of adverse outcome that could be used in routine settings for the management of DLCL patients.

Adult↗
PubMed2005

Dual lympho-myeloproliferative disorder in a patient with t(8;22) with BCR-FGFR1 gene fusion.

The case of a patient presenting with a myeloproliferative disorder (MPD) characterized by a t(8;22) (p12;q11) translocation was investigated. The rearrangement resulted in the production of BCR-FGFR1 and FGFR1-BCR chimeric transcripts after in-frame fusions of BCR exon 4 with FGFR1 exon 9 and FGFR1 exon 8 with BCR exon 5, respectively. The four previously reported patients with such translocation presented with an atypical chronic myeloid leukemia (CML) without Philadelphia chromosome. In addition to a myeloproliferation, the patient had a B cell proliferation. The phenotypic characterization of the lymphoid cells in the bone marrow showed a continuum of maturation from blast B cells to polyclonal lymphocytes. In the blood, B cells showed a complete polyclonal maturation. The BCR-FGFR1 gene fusion was detected by dual-color fluorescence in situ hybridization in both CD19- and CD19+ populations. In contrast to the other FGFR1-MPDs that show myeloid and T cell proliferation, we propose that this t(8;22) MPD is a myeloid and B cell disease, and potentially a novel type of hematological disease. Although the FGFR1-MPD is rare, its study provides interesting clues to the understanding of hematopoietic stem cell biology and oncogene activation.

Aged↗
PubMed2004

Identification of new classes among acute myelogenous leukaemias with normal karyotype using gene expression profiling.

Conventional cytogenetic analysis currently stratifies acute myelogenous leukaemia (AML) into prognostically relevant groups. However, approximately 50% of adult AMLs have normal cytogenetics (NC-AMLs), and represent a heterogeneous and poorly understood group. We analysed gene expression in 55 AML samples including 53 cases from adult patients with NC-AML (n = 36), trisomy 8, t(15;17), t(8;21), t(11;19), 7q deletion, and two cell lines using 9000-gene DNA microarrays. Global hierarchical clustering showed that NC-AMLs are a heterogeneous group. Supervised analysis distinguished two subgroups of NC-AML: one subgroup constituted a homogeneous NC cluster ('pure NC-AML'), and the other NC-AMLs were close to the AML cases with translocations ('translocation like'). Gene expression signatures were also derived for patients with trisomy 8, as well as FLT3 and MLL gene duplications. Importantly, samples from 24 NC-AML patients who could be evaluated for clinical outcome were analysed. In all, 43 genes that discriminated two classes of patients with significantly different prognosis were identified. The poor prognosis class contained a majority of 'pure NC-AMLs', whereas the 'translocation-like' AMLs were in the good prognosis class. Discriminator genes included genes involved in drug resistance (TOP2B), protein transport (MTX2, SLC35A2), and cell signalling (MAPK1, PRKAB2). Our results demonstrate the transcriptional heterogeneity of NC-AMLs, and suggest the existence of 'translocation-like' NC-AMLs and of a gene expression signature that may predict response to chemotherapy.

DNA-Binding Proteins↗
PubMed2004

DNAM-1 and PVR regulate monocyte migration through endothelial junctions.

DNAX accessory molecule 1 (DNAM-1; CD226) is a transmembrane glycoprotein involved in T cell and natural killer (NK) cell cytotoxicity. We demonstrated recently that DNAM-1 triggers NK cell-mediated killing of tumor cells upon engagement by its two ligands, poliovirus receptor (PVR; CD155) and Nectin-2 (CD112). In the present paper, we show that PVR and Nectin-2 are expressed at cell junctions on primary vascular endothelial cells. Moreover, the specific binding of a soluble DNAM-1-Fc molecule was detected at endothelial junctions. This binding was almost completely abrogated by anti-PVR monoclonal antibodies (mAbs), but not modified by anti-Nectin-2 mAbs, which demonstrates that PVR is the major DNAM-1 ligand on endothelial cells. Because DNAM-1 is highly expressed on leukocytes, we investigated the role of the DNAM-1-PVR interaction during the monocyte transendothelial migration process. In vitro, both anti-DNAM-1 and anti-PVR mAbs strongly blocked the transmigration of monocytes through the endothelium. Moreover, after anti-DNAM-1 or anti-PVR mAb treatment, monocytes were arrested at the apical surface of the endothelium over intercellular junctions, which strongly suggests that the DNAM-1-PVR interaction occurs during the diapedesis step. Altogether, our results demonstrate that DNAM-1 regulates monocyte extravasation via its interaction with PVR expressed at endothelial junctions on normal cells.

Antigens, Differentiation, T-Lymphocyte↗
PubMed2004

Intensive sequential chemotherapy with hematopoietic growth factor support for non-Hodgkin lymphoma in patients infected with the human immunodeficiency virus.

BACKGROUND: Optimal treatment of human immunodeficiency virus (HIV)-associated non-Hodgkin lymphoma (NHL) has yet to be defined, because chemotherapy could exacerbate immunodeficiency, with subsequent adverse effects for patients. METHODS: The authors investigated the feasibility of an intensive chemotherapy regimen for HIV-associated NHL. Thirty-eight patients were treated with a first course of cyclophosphamide (Cy), vincristine, and prednisone; followed by 3 courses of high-dose Cy (2000 mg/m2), doxorubicin (Doxo; 50 mg/m2), vincristine, and prednisone (modified high-dose CHOP); 1 course of high-dose methotrexate (MTX; 8000 mg/m2); and 1 course of high-dose cytarabine (8000 mg/m2). Radiotherapy was added to the treatment regimen for patients with bulky disease or residual tumor. Chemotherapy was administered in conjunction with granulocyte-colony-stimulating factor and antiretroviral therapy. RESULTS: Patients received 91.5%, 93%, 66%, and 63% of the scheduled doses of Cy, Doxo, MTX, and cytarabine, respectively. The complete response rate was 60.5%, with a total response rate of 79%. The 40-month overall survival rate was 43%, the disease-free survival rate was 65%, and the recurrence-free survival rate was 39%. Both an International Prognostic Index score of 0 or 1 and Burkitt-type histology had positive effects on survival, whereas CD4-positive lymphocyte counts, viral burden, and previous highly active antiretroviral therapy did not. CD4-positive T lymphocyte levels decreased from 0.197 +/- 0.156 x10(9)/L before treatment to 0.152 +/- 0.1 x10(9)/L at 6 months after the end of treatment. A decrease in viral load, from 380,000 +/- 785,000 copies/mL before treatment to 25,000 +/- 43,000 copies/mL at 6 months after the end of treatment, also was observed. CONCLUSIONS: The results of the current study indicate that intensive chemotherapy is effective and tolerable for patients with HIV-associated NHL.

Adult↗
PubMed2004

Gene expression profiling in anaplastic large cell lymphoma and Hodgkin's disease.

Recent efforts have been made to isolate molecular targets that could explain different outcome between histological subtypes of lymphomas and to understand the molecular mechanisms underlying oncogenic events. Using the SSH technique, we compared the transcriptome of 2 cases of ALK+ and ALK- anaplastic large cell lymphoma (ALCL) and of 2 cases of classical Hodgkin's lymphoma (cHL) with opposite behavior. Regarding ALCL, we showed that ALK-positive tumors overexpressed genes involved in different signaling pathways such as activation or signaling of T-cells, regulation of apoptosis, phospholipase Cgamma and phosphatidyl inositol-3 Kinase. In addition, the characterization of a specific molecular signature may be of clinical relevance since ALK+ tumors generally have a better prognosis than ALK- ones. Similar problems of differential prognosis is observed in cases of cHL, which in addition, may be morphologically and immunologically indistinguishable. Therefore, we applied the same SSH technique to 2 cHL samples from patients with favorable and poor outcome, respectively. Forty-four cDNAs were significantly overexpressed in the poor outcome case. In addition to the defender against death cell 1 (DAD1) gene, overexpressed clones corresponded mostly to expressed sequence tags (ESTs). Interestingly, the present study identifies new genes which may be involved in the pathogenesis and/or clinical outcome of cHL and deserve further investigations.

Gene Expression Profiling↗
PubMed2004

Bone marrow histological patterns can predict survival of patients with grade 1 or 2 follicular lymphoma: a study from the Groupe d'Etude des Lymphomes Folliculaires.

The influence of bone marrow biopsy (BMB) histology on prognosis and management of follicular lymphomas (FL) remains controversial. A total of 390 patients with grade 1 or 2 FL were prospectively included in the multicentric Groupe d'Etude des Lymphomes Folliculaires trial and their BMB reviewed in order (i) to quantify the ratio of lymphomatous foci (LFo) area to that of BMB size (LFo/BMB), (ii) to determine the BMB patterns for a practical grading of marrow infiltration, (iii) to assess the intra- and inter-observer reproducibility of this grading and (iv) to analyse this grading on event-free (EFS) and overall survival (OS), using univariate and multivariate analyses. A total of 267 patients (68%) had BMB involvement, with inter- and intra-observer reproducibility for classifying the patterns of involvement of 91 and 96%, respectively. Uni- and multivariate analyses demonstrated the adverse influence of (i) a ratio of LFo/BMB > or = 0.1, i.e. three or four nodules/medullary space or > or = 1 nodule + foci of diffuse involvement on EFS (P = 0.03) and (ii) two different histological patterns in the same BMB on EFS (P = 0.004) and OS (P = 0.001). This latter finding was only significant in patients with a high tumour burden and remained significant in multivariate analysis. These results indicate that BMB histology can predict survival of FL patients with a high tumour burden, and may help in defining their treatment.

Adolescent↗
PubMed2003

LAT regulates gammadelta T cell homeostasis and differentiation.

LAT (linker for activation of T cells) is essential for T cell receptor signaling. Mice homozygous for a mutation of the three C-terminal LAT tyrosine residues showed a block in alphabeta T cell development and a partially impaired gammadelta T cell development. Without intentional immunization, they accumulated gammadelta T cells in the spleen and lymph nodes that chronically produced T helper type 2 cytokines in large amounts, and caused the maturation of plasma cells secreting immunoglobulin E (IgE) and IgG1. These effects are very similar to that triggered in the alphabeta lineage by a mutation involving a distinct LAT tyrosine. Thus, LAT is an essential regulator of T cell homeostasis and terminal differentiation.

Adaptor Proteins, Signal Transducing↗
PubMed2003

FOP-FGFR1 tyrosine kinase, the product of a t(6;8) translocation, induces a fatal myeloproliferative disease in mice.

Constitutive activation of aberrant fibroblast growth factor receptor 1 (FGFR1) kinase as a consequence of gene fusion such as FOP-FGFR1 associated with t(6; 8)(q27;p11-12) translocation, is the hallmark of an atypical aggressive stem cell myeloproliferative disorder (MPD) in humans. In this study, we show that expression of FOP-FGFR1 in primary bone marrow cells induced by retroviral transduction generates a MPD in mice. Constitutive FOP-FGFR1 kinase activity was both essential and sufficient to cause a chronic myeloproliferative syndrome in the murine bone marrow transplantation model. In contrast to the human disorder, lymphoproliferation and progression to acute phase were not observed. Lymphoid symptoms, however, appeared when onset of the disease was delayed as the result of mutation of FOP-FGFR1 at tyrosine 511, the phospholipase C gamma (PLCgamma) binding site.

Animals↗