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Increased mRNA translation drives carcinogenesis and is an attractive target for the development of new anti-cancer drugs. In this work, we investigated effects of phenethylisothiocyanate (PEITC), a phytochemical with chemopreventive and anti-cancer activity, on mRNA translation. PEITC rapidly inhibited global mRNA translation in human breast cancer-derived MCF7 cells and mouse embryonic fibroblasts (MEFs). In addition to the known inhibitory effects of PEITC on mTORC1 activity, we demonstrate that PEITC increased eIF2α phosphorylation. PEITC also increased formation of stress granules which are typically associated with eIF2α phosphorylation and accumulation of translationally stalled mRNAs. Analysis of genetically modified MEFs demonstrated that optimal inhibition of global mRNA translation by PEITC was dependent on eIF2α phosphorylation, but not mTORC1 inhibition. We extended this study into primary leukemic B cells derived from patients with chronic lymphocytic leukaemia (CLL). CLL cells were stimulated in vitro with anti-IgM to mimic binding of antigen, a major driver of this leukemia. In CLL cells, PEITC increased eIF2α phosphorylation, inhibited anti-IgM-induced mTORC1 activation and decreased both basal and anti-IgM-induced global mRNA translation. PEITC also inhibited transcription and translation of MYC mRNA and accumulation of the MYC oncoprotein, in anti-IgM-stimulated cells. Moreover, treatment of CLL cells with PEITC and the BTK kinase inhibitor ibrutinib decreased anti-IgM-induced translation and induced cell death to a greater extent than either agent alone. Therefore, PEITC can inhibit both global and mRNA specific translation (including MYC) via effects on multiple regulatory pathways. Inhibition of mRNA translation may contribute to the chemopreventive and anti-cancer effects of PEITC.

Changes in DNA copy number (CN) and DNA methylation represent important aberrations for lymphomas and other cancers. Here, for the first time, we show that the Illumina Infinium Methylation (IIM) assay, although not originally designed for CN profiling, is able to estimate CN changes. We compared the IIM CN profiles to those obtained with a standard technique in a series of diffuse large B-cell lymphomas: the profiles showed a high degree of consensus. The demonstration of CN profiling as an additional function of the IIM assay may impact the choice of platform for methylation profiling of haematological and solid tumours., (© 2011 Blackwell Publishing Ltd.)

Elderly chronic lymphocytic leukaemia (CLL) patients treated outside of trials have notably greater toxicity with the Brutons tyrosine kinase inhibitor ibrutinib compared to younger patients. It is not known whether the same holds true for the B-cell lymphoma 2 inhibitor venetoclax. We provide a comprehensive analysis of key safety measures and efficacy in 342 patients comparing age categories ≥75 and

Hairy cell leukemia (HCL) is a rare lymphoproliferative disorder, comprising only 2% of all leukemias. The Hairy Cell Leukemia Foundation (HCLF) has developed a patient data registry to enable investigators to better study the clinical features, treatment outcomes, and complications of patients with HCL. This system utilizes a centralized registry architecture. Patients are enrolled at HCL Centers of Excellence (COE) or via a web-based portal. All data are de-identified, which reduces regulatory burden and increases opportunities for data access and re-use. To date, 579 patients have been enrolled in the registry. Efforts are underway to engage additional COE's to expand access to patients across the globe. This international PDR will enable researchers to study outcomes in HCL in ways not previously possible due to the rarity of the disease and will serve as a platform for future prospective research. [ABSTRACT FROM AUTHOR]

A significant body of literature has been generated related to the detection of measurable residual disease (MRD) at the time of achieving complete remission (CR) in patients with hairy cell leukemia (HCL). However, due to the indolent nature of the disease as well as reports suggesting long-term survival in patients treated with a single course of a nucleoside analog albeit without evidence of cure, the merits of detection of MRD and attempts to eradicate it have been debated. Studies utilizing novel strategies in the relapse setting have demonstrated the utility of achieving CR with undetectable MRD (uMRD) in prolonging the duration of remission. Several assays including immunohistochemical analysis of bone marrow specimens, multi-parameter flow cytometry and molecular assays to detect the mutant BRAF V600E gene or the consensus primer for the immunoglobulin heavy chain gene (IGH) rearrangement have been utilized with few comparative studies. Here we provide a consensus report on the available data, the potential merits of MRD assessment in the front-line and relapse settings and recommendations on future role of MRD assessment in HCL. [ABSTRACT FROM AUTHOR]

The article offers information about the use of venetoclax, a BH3-mimetic agent that targets the antiapoptotic protein BCL2, in the treatment of refractory hairy-cell leukemia, a mature B-cell lymphoid cancer. It mentions that venetoclax was administered, resulting in a significant reduction in leukemic cell infiltration and BCL2 overexpression. The patient received an escalating dose of venetoclax, and the treatment showed promising results.

Keywords: Differential diagnosis; BRAF V600E mutation; hairy Cell Leukaemia; Hairy cell variant; therapy EN Differential diagnosis BRAF V600E mutation hairy Cell Leukaemia Hairy cell variant therapy 730 737 8 12/07/20 20201201 NES 201201 Methodology This guideline was compiled according to the BSH process (https://b-s-h.org.uk/guidelines). Cytoplasm is abundant and pale blue, with circumferential "hairy" projections.9 Discrete cytoplasmic vacuoles or rod-shaped inclusions (ribosome lamellar complexes) may be seen.3 Bone marrow aspirate and trephine biopsy Bone marrow aspiration is frequently unsuccessful, reflecting fibrosis induced by the hairy cell infiltrate. In a single-centre follow-up study of 242 patients,41 18 patients treated with cladribine (12 as first-line and six as second-line therapy) who remained in PR after bone marrow reassessment received a repeat treatment with cladribine 4-7 months after initial treatment, leading to CR in 14 patients, of whom all but one remained in CR at a median follow-up of 6 years. Treatment of relapsed or refractory classical HCL Despite the durable remissions achieved with front-line therapy, approximately 50% of patients will relapse. [Extracted from the article]

A functional B-cell receptor (BCR) is critical for survival of normal B-cells, but whether it plays a comparable role in B-cell malignancy is as yet not fully delineated. Typical Hairy Cell Leukemia (HCL) is a rare B-cell tumor, and unique in expressing multiple surface immunoglobulin (sIg) isotypes on individual tumor cells (mult-HCL), to raise questions as to their functional relevance. Typical mult-HCL also displays a mutated BRAF V(600)E lesion. Since wild type BRAF is a primary conduit for transducing normal BCR signals, as revealed by deletion modelling studies, it is as yet not apparent if mutated BRAF alters BCR signal transduction in mult-HCL. To address these questions, we examined BCR signalling in mult-HCL cases uniformly displaying mutated BRAF and IGHV genes. Two apparent functional sets were delineated by IgD co-expression. In sIgD+ve mult-HCL, IgD mediated persistent Ca2+ flux, also evident via >1 sIgH isotype, linked to increased ERK activation and BCR endocytosis. In sIgD−ve mult-HCL however, BCR-mediated signals and downstream effects were restricted to a single sIgH isotype, with sIgM notably dysfunctional and remaining immobilised on the cell surface. These observations reveal discordance between expression and function of individual isotypes in mult-HCL. In dual sIgL expressing cases, only a single sIgL was fully functional. We examined effects of anti-BCR stimuli on mult-HCL survival ex-vivo. Significantly, all functional non-IgD isotypes increased ERK1/2 phosphorylation but triggered apoptosis of tumor cells, in both subsets. IgD stimuli, in marked contrast retained tumor viability. Despite mutant BRAF, BCR signals augment ERK1/2 phosphorylation, but isotype dictates functional downstream outcomes. In mult-HCL, sIgD retains a potential to transduce BCR signals for tumor survival in-vivo. The BCR in mult-HCL emerges as subject to complex regulation, with apparent conflicting signalling by individual isotypes when co-expressed with sIgD. This suggests the possibility that mutant BRAF by-passes BCR constraints in mult-HCL. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the research study "MGA, a suppressor of MYC, Is Recurrently Inactivated in High Risk Chronic Lymphocytic Leukemia," which appeared in the previous issue.

Several appendixes are presented depicting clinical and biological characteristics of patients with chronic lymphocytic leukaemia and Tp53 disfunction.

Hairy cell leukaemia (HCL) is a rare B-cell neoplasm for which the molecular mechanisms are largely unknown. High-density genome-wide DNA profiling was performed with Affymetrix 250K arrays to analyse copy number (CN) changes and loss of heterozygosity (LOH) in 16 cases of HCL. Four of 16 cases (25%) demonstrated gross non-recurrent CN deletions. Within the affected regions, we identified genes involved in bone marrow fibrosis ( FGF12) and response to treatment ( TP53) in individual cases. Large regions (>5 Mb) of LOH without any concomitant DNA CN changes were identified in 5/16 (31%) HCL and were indicative of uniparental disomy UD. The germline origin of UD was demonstrated in one case for which a matched normal sample was available. Overall analysis of LOH showed that identical loci were recurrently targeted in chromosomes 1, 2 and 6. As a whole, however, HCL showed a remarkably stable genome. This finding adds to several other features that are unique to HCL among mature B-cell tumours. [ABSTRACT FROM AUTHOR]

Recurrent cytogenetic abnormalities are typically found in about one third of B-cell chronic lymphocytic leukemia patients (B-CLL) by standard cytogenetic analysis and their prognostic relevance is well known. We report a case of a B-CLL patient showing both trisomy 12 and a t(14;22)(q32;q11). Trisomy 12 is often associated with aggressive disease and resistance to chemotherapy, however, our patient is in good health and currently untreated after 7 years, suggesting in this case a relatively good prognosis and a questionable role for translocations involving the 14q32 locus. [ABSTRACT FROM AUTHOR]