Author
Jean-Luc Villeval
Other affiliations: Millennium Pharmaceuticals, University of Paris, Université Paris-Saclay ...read more
Bio: Jean-Luc Villeval is an academic researcher from Institut Gustave Roussy. The author has contributed to research in topics: Haematopoiesis & Myelofibrosis. The author has an hindex of 43, co-authored 117 publications receiving 10773 citations. Previous affiliations of Jean-Luc Villeval include Millennium Pharmaceuticals & University of Paris.
Papers published on a yearly basis
Papers
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TL;DR: A clonal and recurrent mutation in the JH2 pseudo-kinase domain of the Janus kinase 2 (JAK2) gene in most (> 80%) polycythaemia vera patients leads to constitutive tyrosine phosphorylation activity that promotes cytokine hypersensitivity and induces erythrocytosis in a mouse model.
Abstract: Myeloproliferative disorders are clonal haematopoietic stem cell malignancies characterized by independency or hypersensitivity of haematopoietic progenitors to numerous cytokines(1,2). The molecular basis of most myeloproliferative disorders is unknown. On the basis of the model of chronic myeloid leukaemia, it is expected that a constitutive tyrosine kinase activity could be at the origin of these diseases. Polycythaemia vera is an acquired myeloproliferative disorder, characterized by the presence of polycythaemia diversely associated with thrombocytosis, leukocytosis and splenomegaly(3). Polycythaemia vera progenitors are hypersensitive to erythropoietin and other cytokines(4,5). Here, we describe a clonal and recurrent mutation in the JH2 pseudo-kinase domain of the Janus kinase 2 (JAK2) gene in most (>80%) polycythaemia vera patients. The mutation, a valine-to-phenylalanine substitution at amino acid position 617, leads to constitutive tyrosine phosphorylation activity that promotes cytokine hypersensitivity and induces erythrocytosis in a mouse model. As this mutation is also found in other myeloproliferative disorders, this unique mutation will permit a new molecular classification of these disorders and novel therapeutical approaches.
3,326 citations
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TL;DR: The sustained correction of X-linked severe combined immunodeficiency disease by ex vivo, retrovirally mediated transfer of the γc gene into CD34+ cells in four of five patients with the disease has been reported.
Abstract: To the Editor: We recently reported (April 18 issue)1 the sustained correction of X-linked severe combined immunodeficiency disease by ex vivo, retrovirally mediated transfer of the γc gene into CD34+ cells in four of five patients with the disease. These results have since been confirmed in four additional patients with typical X-linked severe combined immunodeficiency. Of the first four successfully treated patients, three continue to do well up to 3.6 years after gene therapy, whereas a serious adverse event occurred in the fourth patient. At a routine checkup 30 months after gene therapy, lymphocytosis consisting of a monoclonal population . . .
1,869 citations
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TL;DR: The absolute number of circulating progenitor cells of granulocyte-macrophage, erythroid, and megakaryocyte lineages showed a dose-related increase up to 100-fold after four days of treatment with rG-CSF and often remained elevated two days after the cessation of therapy and in most patients was slightly decreased.
595 citations
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TL;DR: It is demonstrated that JAK2(V617F) is sufficient for polycythemia and fibrosis development and offers an in vivo model to assess novel therapeutic approaches for Jak2( V617F)-positive pathologies.
446 citations
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TL;DR: The genes encoding human and mouse GPVI were identified and functional evidence demonstrating the identity of the recombinant protein with GPVI was shown, and it was demonstrated that the soluble protein blocks Cvx and collagen-induced platelet aggregation and that GPVI expression is restricted to megakaryocytes and platelets.
256 citations
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TL;DR: The classification of myeloid neoplasms and acute leukemia is highlighted with the aim of familiarizing hematologists, clinical scientists, and hematopathologists not only with the major changes in the classification but also with the rationale for those changes.
4,274 citations
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French Institute of Health and Medical Research1, University of Freiburg2, Hospital Research Foundation3, Medical Research Council4, Utrecht University5, Harvard University6, Pasteur Institute7, Babraham Institute8, University of Paris9, Curie Institute10, National Institutes of Health11, University of Sydney12, Ludwig Maximilian University of Munich13, LSU Health Sciences Center New Orleans14
TL;DR: Retrovirus vector insertion can trigger deregulated premalignant cell proliferation with unexpected frequency, most likely driven by retrovirus enhancer activity on the LMO2 gene promoter.
Abstract: We have previously shown correction of X-linked severe combined immunodeficiency [SCID-X1, also known as gamma chain (gamma(c)) deficiency] in 9 out of 10 patients by retrovirus-mediated gamma(c) gene transfer into autologous CD34 bone marrow cells. However, almost 3 years after gene therapy, uncontrolled exponential clonal proliferation of mature T cells (with gammadelta+ or alphabeta+ T cell receptors) has occurred in the two youngest patients. Both patients' clones showed retrovirus vector integration in proximity to the LMO2 proto-oncogene promoter, leading to aberrant transcription and expression of LMO2. Thus, retrovirus vector insertion can trigger deregulated premalignant cell proliferation with unexpected frequency, most likely driven by retrovirus enhancer activity on the LMO2 gene promoter.
3,514 citations
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TL;DR: A clonal and recurrent mutation in the JH2 pseudo-kinase domain of the Janus kinase 2 (JAK2) gene in most (> 80%) polycythaemia vera patients leads to constitutive tyrosine phosphorylation activity that promotes cytokine hypersensitivity and induces erythrocytosis in a mouse model.
Abstract: Myeloproliferative disorders are clonal haematopoietic stem cell malignancies characterized by independency or hypersensitivity of haematopoietic progenitors to numerous cytokines(1,2). The molecular basis of most myeloproliferative disorders is unknown. On the basis of the model of chronic myeloid leukaemia, it is expected that a constitutive tyrosine kinase activity could be at the origin of these diseases. Polycythaemia vera is an acquired myeloproliferative disorder, characterized by the presence of polycythaemia diversely associated with thrombocytosis, leukocytosis and splenomegaly(3). Polycythaemia vera progenitors are hypersensitive to erythropoietin and other cytokines(4,5). Here, we describe a clonal and recurrent mutation in the JH2 pseudo-kinase domain of the Janus kinase 2 (JAK2) gene in most (>80%) polycythaemia vera patients. The mutation, a valine-to-phenylalanine substitution at amino acid position 617, leads to constitutive tyrosine phosphorylation activity that promotes cytokine hypersensitivity and induces erythrocytosis in a mouse model. As this mutation is also found in other myeloproliferative disorders, this unique mutation will permit a new molecular classification of these disorders and novel therapeutical approaches.
3,326 citations
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TL;DR: This work surmises that CRI represents the seventh hallmark of cancer, and suggests that an additional mechanism involved in cancer-related inflammation (CRI) is induction of genetic instability by inflammatory mediators, leading to accumulation of random genetic alterations in cancer cells.
Abstract: Inflammatory conditions in selected organs increase the risk of cancer. An inflammatory component is present also in the microenvironment of tumors that are not epidemiologically related to inflammation. Recent studies have begun to unravel molecular pathways linking inflammation and cancer. In the tumor microenvironment, smoldering inflammation contributes to proliferation and survival of malignant cells, angiogenesis, metastasis, subversion of adaptive immunity, reduced response to hormones and chemotherapeutic agents. Recent data suggest that an additional mechanism involved in cancer-related inflammation (CRI) is induction of genetic instability by inflammatory mediators, leading to accumulation of random genetic alterations in cancer cells. In a seminal contribution, Hanahan and Weinberg [(2000) Cell, 100, 57-70] identified the six hallmarks of cancer. We surmise that CRI represents the seventh hallmark.
2,475 citations
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TL;DR: With the development of a leukaemia-like syndrome in two patients cured of a disease by gene therapy, it is timely to contemplate how far this technology has come, and how far it still has to go.
Abstract: Gene therapy has a history of controversy. Encouraging results are starting to emerge from the clinic, but questions are still being asked about the safety of this new molecular medicine. With the development of a leukaemia-like syndrome in two of the small number of patients that have been cured of a disease by gene therapy, it is timely to contemplate how far this technology has come, and how far it still has to go.
2,451 citations