Toll-like receptor expression and function differ between splenic marginal zone B cell lymphoma and splenic diffuse red pulp B cell lymphoma.

In splenic marginal zone lymphoma (SMZL), specific and functional Toll-like Receptor (TLR) patterns have been recently described, suggesting their involvement in tumoral proliferation. Splenic diffuse red pulp lymphoma with villous lymphocytes (SDRPL) is close to but distinct from SMZL, justifying here the comparison of TLR patterns and functionality in both entities. Distinct TLR profiles were observed in both lymphoma subtypes.

Exome sequencing identifies recurrent alterations and the absence of , and mutations in splenic diffuse red pulp small B-cell lymphoma.

Splenic diffuse red pulp lymphoma is an indolent small B-cell lymphoma recognized as a provisional entity in the World Health Organization 2008 classification. Its precise relationship to other related splenic B-cell lymphomas with frequent leukemic involvement or other lymphoproliferative disorders remains undetermined. We performed whole-exome sequencing to explore the genetic landscape of ten cases of splenic diffuse red pulp lymphoma using paired tumor and normal samples.

The ibrutinib B-cell proliferation inhibition is potentiated in vitro by dexamethasone: Application to chronic lymphocytic leukemia.

New B-cell receptor-targeted therapies such as ibrutinib, a Bruton tyrosine kinase inhibitor, are now proposed for lymphoid pathologies. The putative benefits of its combination with glucocorticoids were evaluated here. We compared the effects of dexamethasone (DXM), ibrutinib and their in vitro combination on proliferation and metabolic stress markers in stimulated normal B-lymphocytes and in malignant lymphocytes from chronic lymphocytic leukemia (CLL) patients.

Molecular characterization and follow-up of five CML patients with new BCR-ABL1 fusion transcripts.

We report five chronic myeloid leukaemia (CML) patients in whom we identified and characterized undescribed BCR-ABL1 fusion transcripts. We investigated the precise features of the molecular rearrangements and the minimal residual disease follow-up for these five patients. Three resulted from new rearrangements between the BCR and ABL1 sequences (the breakpoints being located within BCR exon 13 in two cases and within BCR exon 18 in one case).

Major molecular response achievement in CML Patients can be predicted by BCR-ABL1/ABL1 or BCR-ABL1/GUS ratio at an earlier time point of follow-up than currently recommended.

Recent studies demonstrate that early molecular response to tyrosine-kinase inhibitors is strongly predictive of outcome in chronic myeloid leukemia patients and that early response landmarks may identify patients at higher risk for transformation who would benefit from an early switch to second-line therapy. In this study, we evaluated the ability of the control gene GUS to identify relevant thresholds for known therapeutic decision levels (BCR-ABL1/ABL1IS  = 10% and 0.1%).

Alarms and parameters generated by hematology analyzer: new tools to predict and quantify circulating Sezary cells.

Background: The rigorous cytological review by manual or automatic microscopic analysis is critical in the detection of circulating neoplastic cells, since their morphology as well as their count contributes to the diagnosis and prognosis of many diseases. However, the cytological analysis is not always obvious and requires trained and competent cytologist. In this context, the alarms and/or parameters generated by hematology analyzer could be particularly informative to alert the operators.

New Quantitative Method to Identify NPM1 Mutations in Acute Myeloid Leukaemia.

Somatic mutations in the NPM1 gene, which encodes for nucleophosmin, have been reported to be the most frequent genetic abnormalities found in acute myeloid leukaemia (AML). Their identification and quantification remain crucial for the patients' residual disease monitoring. We investigated a new method that could represent a novel reliable alternative to sequencing for its identification.

High DNA methyltransferase DNMT3B levels: a poor prognostic marker in acute myeloid leukemia.

It has been recently shown that DNA methyl transferase overexpression is correlated with unfavourable prognosis in human malignancies while methylation deregulation remains a hallmark that defines acute myeloid leukemia (AML). The oncogenic transcription factor EVI1 is involved in methylation deregulation and its overexpression plays a major role for predicting an adverse outcome. Moreover, the identification of DNMT3A mutations in AML patients has recently been described as a poor prognostic indicator.

In non-follicular lymphoproliferative disorders, IGH/BCL2-fusion is not restricted to chronic lymphocytic leukaemia.

The translocation t(14;18) and its t(2;18) and t(18,22) variants, which involve the BCL2 genetic hallmark for follicular lymphoma (FL), have been reported in several cases of chronic B-cell lymphoproliferative disease (CLPD) and frequently in chronic lymphocytic leukaemia (CLL). We describe here the clinical, morphological, immunological, cytogenetic and molecular findings from 37 cases of t(14;18)-positive CLPD, identified from our series of non-FL B-cell neoplasms (n=993) that were routinely analysed in peripheral blood by conventional cytogenetics analyses. The FL diagnosis was excluded by morphology and immunology (the samples were CD10 negative in all cases).

CD10 and ICOS expression by multiparametric flow cytometry in angioimmunoblastic T-cell lymphoma.

Angioimmunoblastic T-cell lymphoma is immunologically defined by the expression of CD10 and the follicular helper T cell (T(FH)) markers such as CXCL13, programmed death-1 (PD-1) and inducible T-cell costimulator (ICOS). This T(FH) profile has been mainly reported by immunohistochemistry. Here, using multiparametric flow cytometry, the relevance of ICOS and PD-1 to angioimmunoblastic T-cell lymphoma diagnosis was evaluated in lymph node (n=15) as well as in peripheral blood (n=13) among a series of 28 angioimmunoblastic T-cell lymphoma cases, in addition to the CD10 expression (available in 26 lymph node and 15 peripheral blood specimens).

The durable clearance of the T315I BCR-ABL mutated clone in chronic phase chronic myelogenous leukemia patients on omacetaxine allows tyrosine kinase inhibitor rechallenge.

Purpose: The onset of a BCR-ABLT315I mutation during the course of chronic myelogenous leukemia (CML) on tyrosine kinase inhibitors (TKIs) usually results in poor survival, and therapeutic options remain few in the absence of any allogeneic donor.

Patients And Methods: We have investigated the affect of subcutaneous omacetaxine (OMA, or homo-harringtonine) cycles on unmutated and T315I-mutated BCR-ABL transcripts in a series of 8 TKI-resistant chronic-phase CML patients and we have addressed the question of whether the administration of OMA could resensitize patients to TKIs. Patients were regularly monitored for total disease burden and for BCR-ABLT315I transcripts using a new quantitative sensitive technique (sensitivity threshold, 0.

Longitudinal studies of SRC family kinases in imatinib- and dasatinib-resistant chronic myelogenous leukemia patients.

This report aims to more accurately define the frequency of the involvement of SRC Family Kinases (SFKs) in imatinib- and dasatinib-resistant CML patients. Clinical samples were analysed during in vivo treatment. We confirmed the high frequency of SFKs involvement in Tyrosine kinase inhibitor-resistant CML (52% of the cases) and even further in progressive disease and blast crises (60% of the cases).

Pegylated IFN-α2a combined to imatinib mesylate 600mg daily can induce complete cytogenetic and molecular responses in a subset of chronic phase CML patients refractory to IFN alone or to imatinib 600mg daily alone.

This phase I/II study was designed to demonstrate the tolerance and the efficacy of a combination of pegylated interferon-α 2a to Imatinib mesylate (IM) 600mg daily in cytogenetically IM-resistant but in CHR chronic phase CML patients. The combination was generally well tolerated in the 15 evaluable patients. A significant reduction of the Ph1(+) BM metaphases was observed in these poor prognosis patients, with 2 long-term CCyR including 2 MMR.

Two new miR-16 targets: caprin-1 and HMGA1, proteins implicated in cell proliferation.

Background Information: miRNAs (microRNAs) are a class of non-coding RNAs that inhibit gene expression by binding to recognition elements, mainly in the 3' UTR (untranslated region) of mRNA. A single miRNA can target several hundred mRNAs, leading to a complex metabolic network. miR-16 (miRNA-16), located on chromosome 13q14, is involved in cell proliferation and apoptosis regulation; it may interfere with either oncogenic or tumour suppressor pathways, and is implicated in leukaemogenesis.

Emergence of therapy-unrelated CML on a background of BCR-ABL-negative JAK2V617F-positive chronic idiopathic myelofibrosis.

We report the emergence of a chronic myeloid leukaemia (CML) during the course of a JAK2V617F-positive chronic idiopathic myelofibrosis (CIMF) in the absence of any myelosuppressive treatment. Although a response to imatinib was observed, the underlying myelofibrosis persisted after treatment and hydroxyurea was finally added to control the persistent thrombocytosis. Such rare patients with co-existing BCR-ABL translocation and JAK2V617F mutation must be identified in view of the possibility of targeted therapies.

Splenic red pulp lymphoma with numerous basophilic villous lymphocytes: a distinct clinicopathologic and molecular entity?

The presence of circulating villous lymphocytes (VLs) in lymphoma patients usually points to splenic marginal zone B-cell lymphoma (SMZL), even if the VLs can be found occasionally in other small B-cell lymphomas. However, those cells are variably described, and detailed cytologic characterization is often lacking. We identified lymphoma cases with numerous basophilic VLs among the large group of splenic lymphoma with VLs, and for further delineation, 37 cases with this particular cytology were analyzed.

Detailed characterization of 7q deletions by multicolor banding (mBAND) in marginal zone cell lymphoma.

High-resolution multicolor banding (mBAND) analysis was applied to precisely fine-map the genomic extent of 7q deletions in a series of 26 marginal zone lymphoma patients displaying the abnormality on conventional karyotypes. Using this approach, the breakpoints and the extent of deletions revealed by conventional banding techniques had to be re-defined in 70% of cases. Although no common minimal region of deletion was delineated, mBAND demonstrated the involvement of the 7q32 region in more than 90% of cases.

BCR-ABL mutant kinetics in CML patients treated with dasatinib.

Dasatinib is efficient in vitro against most of CML cells harboring ABL kinase domain mutations and induces high rates of response in imatinib-resistant CML patients. Here, we monitored the mutated BCR-ABL transcripts during the follow-up of 12 CML patients treated with dasatinib. We identified four groups of patients based on their sensitivity to dasatinib.

The expression of TCR-gamma delta/CD3 complex in neoplastic gamma delta T-cell.

We describe that the neoplastic gammadelta T-cells from patients with hepatosplenic gammadelta T-cell lymphoma have a lower expression of TCR-gammadelta/CD3 complex compared to their normal or reactive counterparts. Interestingly, with the use of an appropriate antibody association, this feature is easily and rapidly observed on flow cytometry graphics.

Atypical cytogenetic presentation of t(11;14) in mantle cell lymphoma.

Eighteen cases of mantle cell lymphomas (MCL) with an atypical t(11;14) were studied using fluorescence in situ hybridization experiments (FISH). The atypical presentation was confirmed and unsuspected duplicated cases were identified in six patients. These data underline that FISH analysis must be be systematically performed in cases with an aberrant presentation to prevent a misdiagnosis.

An unusual case of indolent B-cell lymphoma with distinct chronic lymphocytic leukemia and marginal zone differentiation according to the site of involvement.

The immunological profile of lymphoproliferative disorders is usually conserved whatever the involved site, thus allowing a reliable diagnosis from peripheral blood analysis, especially in small lymphocytic lymphoma/chronic lymphocytic lymphoma (SLL/CLL). Here we present a case wherein the cytology and immunophenotype of blood specimen and bone marrow argue in favor of SLL/CLL with a typical Matutes score (5/5), whereas the cyto-histology and immunophenotype of spleen specimen led to the diagnosis of splenic marginal zone B-cell lymphoma (SMZL). Moreover genomic analysis showed that the splenic cells displayed a SMZL signature.

AF4p12, a human homologue to the furry gene of Drosophila, as a novel MLL fusion partner.

More than 35 different partner genes with the mixed lineage leukemia (MLL) gene have been cloned from leukemia cells with translocations involving chromosome 11 band q23. In this study, we report on a novel fusion partner of the MLL gene, AF4p12, which we have identified as the human homologue to the furry gene of Drosophila. AF4p12, highly conserved in evolution, encodes a large protein of 3,105 amino acids.