0000000000730567
AUTHOR
Selim Ramla
Identification of novel, clonally stable, somatic mutations targeting transcription factors PAX5 and NKX2-3, the epigenetic regulator LRIF1, and BRAF in a case of atypical B-cell chronic lymphocytic leukemia harboring a t(14;18)(q32;q21)
Diagnosis of B-cell chronic lymphocytic leukemia (B-CLL) is usually straightforward, involving clinical, immunophenotypic (Matutes score), and (immuno)genetic analyses (to refine patient prognosis for treatment). CLL cases with atypical presentation (e.g., Matutes ≤ 3) are also encountered, and for these diseases, biology and prognostic impact are less clear. Here we report the genomic characterization of a case of atypical B-CLL in a 70-yr-old male patient; B-CLL cells showed a Matutes score of 3, chromosomal translocation t(14;18)(q32;q21) (BCL2/IGH), mutated IGHV, deletion 17p, and mutations in BCL2, NOTCH1 (subclonal), and TP53 (subclonal). Quite strikingly, a novel PAX5 mutation that w…
Calreticulin Mutations in Myeloproliferative Neoplasms: Comparison of Three Diagnostic Methods
International audience; Calreticulin (CALR) mutations have recently been reported in 70-84% of JAK2V617F-negative myeloproliferative neoplasms (MPN), and this detection has become necessary to improve the diagnosis of MPN. In a large single-centre cohort of 298 patients suffering from Essential Thrombocythemia (ET), the JAK2V617F, CALR and MPL mutations were noted in 179 (60%), 56 (18.5%) and 13 (4.5%) respectively. For the detection of the CALR mutations, three methods were compared in parallel: high-resolution melting-curve analysis (HRM), product-sizing analysis and Sanger sequencing. The sensitivity for the HRM, product-sizing analysis and Sanger sequencing was 96.4%, 98.2% and 89.3% re…
HSP27: A Therapeutic Target in Myelofibrosis
Abstract Myelofibrosis (MF) is the most aggressive myeloproliferative neoplasms (MPN) with the highest degree of morbidity and mortality, including progressive bone marrow fibrosis resulting into bone marrow failure. JAK2 kinase inhibitors have been successfully used for a few years in MPN and more particularly for MF treatment. Despite their beneficial effects on spleen size and symptoms, JAK2 inhibitors induce low molecular and survival responses underscoring the urgent need for other therapeutic approaches. Recently, heat shock protein 90 (HSP90) - known to stabilize JAK2 - has been reported as a promising therapeutic target in MPN. However HSP90 inhibitors show toxicity and induce the e…
HSP110 sustains chronic NF-κB signaling in activated B cell diffuse large B cell lymphoma through MyD88 stabilization
International audience; Activated B cell diffuse large B cell lymphoma (ABC-DLBCL) is an aggressive lymphoproliferative disorder involving chronic NF-κB activation. Several mutations in the BCR and the MyD88 signaling pathway components, such as MyD88 L265P, are implicated in this aberrant activation. Among heat-shock proteins, HSP110 has recently been identified as a pro- survival and/or proliferation factor in many cancers but its role in ABC-DLBCL survival mechanisms remained to be established. We observed that shRNA-mediated HSP110 silencing decreased the survival of several ABC-DLBCL cell lines, decreased IgM-MyD88 co-localization and subsequent NF-κB signaling. Conversely, over-expres…