THE EXPRESSION OF THE MAIN AND ALTERNATIVE TRANSCRIPT (SORL1 Delta2) OF THE SORL1 GENE IN CHRONIC LYMPHOCYTIC LEUKEMIA PATIENTS AFFECTED BY THE CHORNOBYL ACCIDENT

OBJECTIVE

to study clinical-hematological data and expression of the main and alternative transcripts of SORL1 genein chronic lymphocytic leukemia (CLL) patients affected by the Chornobyl catastrophe.

METHODS

Analysis was performed in the main group of 34 CLL patients irradiated due to the Chornobyl NPP acci-dent (30 clean-up workers, and 4 evacuees) and in the control group of 27 non-irradiated CLL patients. Groups ofpatients were comparable by age, sex, stage of disease, mutational status of IGHV genes. Expression of the main andalternative transcripts of SORL1 gene was evaluated by Quantitative Real-time polymerase chain reaction (PCR). TheIGHV gene mutational status, TP53 and SF3B1 mutations were studied by PCR followed by direct sequencing. Data wereanalyzed with the SPSS software package, version 20.0.

RESULTS

Relative expression level of the main transcript of SORL1 gene was low (mean 1.71 ± 0.55, median 0.57),did not correlate with the IGHV gene mutational status, TP53 and SF3B1 mutations, stage of disease. The expressionof B transcript was not detected, F transcript was expressed at a very low level in 9 patients. The average relativeexpression level of SORL1-Δ2 transcript was 14.1 ± 6.04 (median 3.48; range 0.01-90.51). The expression of SORL1-Δ2transcript above the median was more frequent among patients on C stage (p = 0.001), and in patients with unmu-tated IGHV genes was associated with an extremely negative course of CLL (median of overall survival 9 months vs61 months at low expression). Relative expression levels of the main and alternative transcripts of SORL1 gene inpatients of the main and the control groups did not differ.

CONCLUSIONS

Our preliminary data suggest that increased expression of SORL1-Δ2 transcript in CLL patients withunmutated IGHV genes can be considered as a negative prognostic marker.

MODIFICATION OF THE TUMOR/INDUCED BYSTANDER EFFECT BY IRRADIATION UNDER COCULTIVATION OF LYMPHOCYTES FROM PATIENTS WITH CHRONIC LYMPHOCYTIC LEUKEMIA AND LYMPHOCYTES FROM HEALTHY DONORS

OBJECTIVE

Study the tumor-induced bystander effect of blood cells from chronic lymphocytic leukemia (CLL)patients on non-transformed bystander cells (peripheral blood lymphocytes (PBL) of conditionally healthy individ-uals) and the possibility of its modification after the impact of ionizing radiation.

MATERIALS AND METHODS

We carried out cocultivation and separate cultivation of blood samples from conditionallyhealthy volunteers and patients with CLL according to our technique. Using the Comet assay, the relative level ofDNA damage was evaluated.

RESULTS

A statistically significant increase (р < 0.001) in the level of DNA damage in PBL culture of conditionallyhealthy individuals after co-cultivation with malignant cells of CLL patients was observed. After irradiation, a drop in the level of cells with a high degree of DNA damage was noted, which was connected with an increase in the frequency of cells that were delayed in division at the S stage of the cell cycle. An increase in apoptotic activity in cultures of bystander cells was observed in all variants of the experiment (р < 0.001).

CONCLUSION

The influence of irradiated blood cells of patients with CLL results in an enhancement of the tumor-induced bystander effect manifestation in the PBL of conditionally healthy individuals.

Evidence for Non-Cancer-Specific T Cell Exhaustion in the Tcl1 Mouse Model for Chronic Lymphocytic Leukemia

The reinvigoration of anti-cancer immunity by immune checkpoint therapies has greatly improved cancer treatment. In chronic lymphocytic leukemia (CLL), patients as well as in the Tcl1 mouse model for CLL, PD1-expressing, exhausted T cells significantly expand alongside CLL development; nevertheless, PD1 inhibition has no clinical benefit. Hence, exhausted T cells are either not activatable by simple PD1 blocking in CLL and/or only an insufficient number of exhausted T cells are CLL-specific. In this study, we examined the latter hypothesis by exploiting the Tcl1 transgenic CLL mouse model in combination with TCR transgene expression specific for a non-cancer antigen. Following CLL tumor development, increased PD1 levels were detected on non-CLL specific T cells that seem dependent on the presence of (tumor-) antigen-specific T cells. Transcriptome analysis confirmed a similar exhaustion phenotype of non-CLL specific and endogenous PD1pos T cells. Our results indicate that in the CLL mouse model, a substantial fraction of non-CLL specific T cells becomes exhausted during disease progression in a bystander effect. These findings have important implications for the general efficacy assessment of immune checkpoint therapies in CLL.

[TIM-3/galectin-9 is involved in negative regulation of T cells in patients with chronic lymphocytic leukemia]

Objective To investigate the regulation and clinical significance of T cell immunoglobulin and mucin domain-containing molecule 3 (TIM-3)/galectin-9 signaling pathway in regulatory T cells (Tregs) and Th17 cells in patients with chronic lymphocytic leukemia (CLL). Methods The study enrolled 36 healthy individuals and 40 newly diagnosed CLL patients. The Tregs, Th17 cells, TIM-3⁺ Tregs and TIM-3⁺ Th17 cells were detected by the flow cytometry in their peripheral blood. Concentrations of IL-10, IL-17 and galectin-9 in serum were measured by the ELISA. Results Compared with the healthy controls, the CLL group had the higher levels of TIM-3⁺ Tregs, Tregs/Th17 cell ratio, TIM-3⁺ Tregs/TIM-3⁺ Th17 cell ratio, IL-10, galectin-9, and IL-10/IL-17 ratio. The level of TIM-3 expression on T cells, galectin-9 and the IL-10/IL-17 ratio in the CLL patients increased with the advance of Binet stage. Conclusion The TIM-3/galectin-9 signaling pathway is involved in the negative regulation of T cells in patients with CLL.

Ulcerated cutaneous Richter syndrome

Richter syndrome or Richter transformation comprises the conversion of chronic lymphocytic leukemia into an aggressive type of large cell lymphoma. Classically, patients have diffuse and abrupt lymphadenopathy and organomegaly, in addition to fever, weight loss, and fatigue. Cutaneous involvement is rare and often nonspecific. We report a patient with chronic lymphocytic leukemia who presented with a large and rapidly evolving ulcer, revealed to be a high-grade cutaneous lymphoma.

BRD4 Profiling Identifies Critical Chronic Lymphocytic Leukemia Oncogenic Circuits and Reveals Sensitivity to PLX51107, a Novel Structurally Distinct BET Inhibitor

Bromodomain and extra-terminal (BET) family proteins are key regulators of gene expression in cancer. Herein, we utilize BRD4 profiling to identify critical pathways involved in pathogenesis of chronic lymphocytic leukemia (CLL). BRD4 is overexpressed in CLL and is enriched proximal to genes upregulated or de novo expressed in CLL with known functions in disease pathogenesis and progression. These genes, including key members of the B-cell receptor (BCR) signaling pathway, provide a rationale for this therapeutic approach to identify new targets in alternative types of cancer. Additionally, we describe PLX51107, a structurally distinct BET inhibitor with novel in vitro and in vivo pharmacologic properties that emulates or exceeds the efficacy of BCR signaling agents in preclinical models of CLL. Herein, the discovery of the involvement of BRD4 in the core CLL transcriptional program provides a compelling rationale for clinical investigation of PLX51107 as epigenetic therapy in CLL and application of BRD4 profiling in other cancers.Significance: To date, functional studies of BRD4 in CLL are lacking. Through integrated genomic, functional, and pharmacologic analyses, we uncover the existence of BRD4-regulated core CLL transcriptional programs and present preclinical proof-of-concept studies validating BET inhibition as an epigenetic approach to target BCR signaling in CLL. Cancer Discov; 8(4); 458-77. ©2018 AACR.This article is highlighted in the In This Issue feature, p. 371.

State Institution «National Research Center for Radiation Medicine of the National Academy of Medical Sciences of Ukraine» - research activities and scientific advance in 2016

Research activities and scientific advance achieved in 2016 at the State Institution «National Research Center for Radiation Medicine of the National Academy of Medical Sciences of Ukraine» (NRCRM) concerning medical problems of the Chornobyl disaster, radiation medicine, radiobiology, radiation hygiene and epidemiology in collaboration with the WHO network of medical preparedness and assistance in radiation accidents are outlined in the annual report. The report presents the results of fundamental and applied research works of the study of radiation effects and health effects of the Chornobyl accident; fulfillment of tasks of «State social program for improving safety, occupational health and working environment in 2014-2018 years».The report also shows the results of scientific organizational and health care work, staff training. The NRCRM Annual Report was approved at the Scientific Council meeting of NAMS on March 17, 2016.

Chronic lymphocytic leukaemia: An updated approach to diagnosis and management in general practice

BACKGROUND

Chronic lymphocytic leukaemia (CLL) is the most common lymphoproliferative disease in Australia. Improvements in the understanding of this disease have led to drastic changes in regards to diagnosis, management and prognosis.

OBJECTIVE

The aim of this article is to give an updated approach to the diagnosis, investigation, monitoring and new treatments of CLL.

DISCUSSION

With the advent of new medications and improved investigations to predict outcomes, CLL has now become a chronic disease that requires long-term monitoring by haematologists and general practitioners (GPs).

A Personalized Framework for Dynamic Modeling of Disease Trajectories in Chronic Lymphocytic Leukemia

Chronic lymphocytic leukemia (CLL) is the most common peripheral blood and bone marrow cancer in the developed world. This manuscript proposes mathematical model equations representing the disease dynamics of B-cell CLL. We interconnect delay differential cell cycle models in each of the tumor-involved disease centers using physiologically relevant cell migration. We further introduce five hypothetical case studies representing CLL heterogeneity commonly seen in clinical practice and demonstrate how the proposed CLL model framework may capture disease pathophysiology across patient types. We conclude by exploring the capacity of the proposed temporally- and spatially distributed model to capture the heterogeneity of CLL disease progression. By using global sensitivity analysis, the critical parameters influencing disease trajectory over space and time are: 1) the initial number of CLL cells in peripheral blood, the number of involved lymph nodes, the presence and degree of splenomegaly; 2) the migratory fraction of nonproliferating as well as proliferating CLL cells from bone marrow into blood and of proliferating CLL cells from blood into lymph nodes; and 3) the parameters inducing nonproliferative cells to proliferate. The proposed model offers a practical platform that may be explored in future personalized patient protocols once validated.

PI3K Signaling in Normal B Cells and Chronic Lymphocytic Leukemia (CLL)

B cells provide immunity to extracellular pathogens by secreting a diverse repertoire of antibodies with high affinity and specificity for exposed antigens. The B cell receptor (BCR) is a transmembrane antibody, which facilitates the clonal selection of B cells producing secreted antibodies of the same specificity. The diverse antibody repertoire is generated by V(D)J recombination of heavy and light chain genes, whereas affinity maturation is mediated by activation-induced cytidine deaminase (AID)-mediated mutagenesis. These processes, which are essential for the generation of adaptive humoral immunity, also render B cells susceptible to chromosomal rearrangements and point mutations that in some cases lead to cancer. In this chapter, we will review the central role of PI3K s in mediating signals from the B cell receptor that not only facilitate the development of functional B cell repertoire, but also support the growth and survival of neoplastic B cells, focusing on chronic lymphocytic leukemia (CLL) B cells. Perhaps because of the central role played by PI3K in BCR signaling, B cell leukemia and lymphomas are the first diseases for which a PI3K inhibitor has been approved for clinical use.

Chylothorax Associated with Chronic Lymphocytic Leukemia

An 80-year-old man who had suffered from chronic lymphocytic leukemia (CLL) and achieved complete remission was admitted to our hospital due to right pleural effusion. Thoracentesis revealed that the effusion was chyle. Lymphoscintigraphy showed an obstruction of the thoracic duct below the sternum. CD45-gated flow cytometry of the pleural effusion showed elevated numbers of CD5- and CD23-positive lymphocytes and a high serum level of soluble interleukin-2 receptor. These results suggested that the chylothorax was caused by the obstruction of the thoracic duct by the sludging of either abnormal lymphocytes of CLL or transformed malignant lymphoma cells.

Chronic Lymphocytic Leukemia: Current Concepts

Chronic lymphocytic leukemia (CLL) is the most common type of leukemia in adults, and while in early, asymptomatic stages treatment is not indicated, the threat to the quality of life and increased mortality of patients posed by more advanced-stage disease necessitate therapeutic intervention. Guidelines of when and how to treat are not well-established because CLL is a disease of the elderly and it is important to balance preservation of functional status and control of the disease. Advances in molecular and genetic profiling has led to the ability to identify sub-groups of patients with CLL whose disease may respond to selected therapy. This review discusses current standard therapies in the major sub-groups of CLL based on age and functional status, in both the front-line and relapsed/refractory settings. It also provides a concise review of novel agents that have shown considerable efficacy in CLL.

[The indicators of alteration of functional activity of vessel wall as new diagnostic criteria of development of initial stages of chronic lymphatic leukemia]

The role of endothelium dysfunction in pathogenesis of B-cell mode of chronic lymphatic leukemia is still uncovered. However, detection of disorders of functional activity of vessel wall at early stages of development of this disease permits to widen actual diagnostic criteria of its initiation and thereafter to make more objective diagnostic itself. The study was targeted to establish the role of endothelium dysfunction in pathogenesis of initial stages (0-1 stages according classification Rai K. et al. 1975) of B-cell mode of chronic lymphatic leukemia. The article presents results of clinical laboratory examination of 30 patients with initial stages of B-cell mode of chronic lymphatic leukemia. The content of classic markers of endothelium dysfunction in blood serum were detected using one time solid-phase enzymoimmunoassay at the moment of admission to hospital before initiation of treatment. In patients with chronic lymphatic leukemia blood serum characterized by increasing of level of E-selectin. ICAM-1, endothelin-1, metabolites of nitrogen nitrite, angiotensin II. At the same time, content of protein C decreased at the stage 0-1 of mentioned pathology. Hence, it is recommended to apply determining in blood serum the content of markers of endothelium dysfunction as additional diagnostic criteria of development of paraneoplastic disorders at initial stages of chronic lymphatic leukemia. These markers include molecules of adhesion (E-selectin, ICAM-I), metabolites of nitrogen nitrite, endothelin-1, protein C. angiotensin II and homocysteine.

Mutations in chronic lymphocytic leukemia and how they affect therapy choice: focus on NOTCH1, SF3B1, and TP53

Chronic lymphocytic leukemia (CLL) is characterized by a relatively small number of recurrent genetic defects. These can be evaluated by clinically available methods such as fluorescent in situ hybridization and targeted sequencing approaches to provide data that can be very helpful in prognostication and planning of treatment. Acquired defects in the p53 pathway, activating mutations of NOTCH1, and dysfunctional mutations of SF3B1 and BIRC3 identify patients with higher risk of progressive disease, poorer responses to conventional chemoimmunotherapy, and shorter survival. Risk stratification using these data can identify patients with aggressive CLL who require careful monitoring and are unlikely to have durable responses to chemoimmunotherapy at disease progression. Patients with defective DNA damage repair mechanisms because of p53 dysfunction should be considered for non-chemotherapy-based regimens including tyrosine kinase inhibitors, BCL2 inhibitors, monoclonal antibodies, and immunological therapies including allogeneic transplantation and chimeric antigen receptor-targeted T cells. Conversely, patients with no high-risk mutations can usually be monitored for a prolonged time and are likely to have durable responses to chemoimmunotherapy at disease progression. New technologies for genetic analysis such as targeted next-generation sequencing have the potential to make these analyses cheaper, faster, and more widely available. Comprehensive genetic analysis of patients both at diagnosis and before treatment for progressive disease could become an integral component of care for CLL.

Metadherin contribute to BCR signaling in chronic lymphocytic leukemia

We have reported Metadherin (MTDH) was proven to be overexpression and involved in malignance of chronic lymphocytic leukemia (CLL) via Wnt signaling pathway. In this study, we further investigate the role of MTDH in regulation of BCR signaling pathway in CLL. Six CLL samples whose cells were proliferation after BCR activation were chosen from patients with unmutated IgVH. CCK-8 method used to evaluate the proliferation rate. MTDH expression was measured by quantitative PCR and Western blot. After BCR activation, there exist upregulation of MTDH expression in mRNA and protein level in all six CLL patients (P<0.05). In cell line MEC-1, we observed the same pro-proliferation effect accompanying with elevated MTDH expression. The proliferation effects of BCR activation to MEC-1 can be inhibited by MTDH interference. The results of this study indicate that MTDH involved in the pro-proliferation effect of BCR activation in CLL. And the results imply that MTDH can be a potential therapy target of CLL.

Hodgkin lymphoma and hypothermia: case report and review of the literature

We report the development of hypothermia in a patient with Hodgkin lymphoma which resolved with chemotherapy administration. A review of the literature revealed 16 previous reports of hypothermia in patients with Hodgkin lymphoma. Overall prognosis seems to be unfavorable. To the best of our knowledge this is the first report of hypothermia in a patient with Hodgkin lymphoma transforming from chronic lymphocytic leukemia (Richter's syndrome). A possible pathophysiology could be paraneoplastic autonomic neuropathy. Physicians should be aware that Hodgkin lymphoma can present with hypothermia and should carefully monitor newly diagnosed patients with advanced disease for this complication. Likewise, patients with Hodgkin lymphoma who develop hypothermia should be screened for signs of autonomic neuropathy.

The pathogenic relevance of the prognostic markers CD38 and CD49d in chronic lymphocytic leukemia

The interactions of chronic lymphocytic leukemia cells with the microenvironment in secondary lymphoid tissues and the bone marrow are known to promote CLL cell survival and proliferation. CD38 and CD49d are both independent prognostic risk parameters in CLL with important roles in shaping these interactions. Both are reported to influence CLL cell trafficking between blood and lymphoid organs as well as their survival and proliferation within the lymphoid organs, thereby impacting the pathophysiology of the disease. The expression of CD38 and CD49d is associated in the majority of cases, and they exist as part of macromolecular complexes. Here, we review the current evidence for the individual and associated contributions of these molecules to CLL pathophysiology.

Ophthalmic manifestations of haematological disorders

Five case histories are presented. Waldenstrom's macroglobulinaemia caused bilateral central retinal vein occlusion, proptosis was the presenting feature of retro-orbital plasmacytoma in relapsed multiple myeloma, a red painful eye was due to neovascular glaucoma in primary polycythaemia, bilateral VIth nerve palsy caused convergent squint and diplopia in meningeal relapse of acute lymphoblastic leukaemia and lymphoma of the eyelid caused complete ptosis. Interdisciplinary management is described. Ophthalmological lesions in haematological disease should be promptly recognized and managed. Collaboration between ophthalmology and haematology departments may be effective for palliative management.

The coexistence of chronic lymphocytic leukemia and myeloproliperative neoplasms: a retrospective multicentric GIMEMA experience

Although the coexistence of chronic lymphocytic leukemia (CLL) and myeloproliferative neoplasms (MPN) has been sporadically reported in the literature, no systematic studies on this disease association are available. We retrospectively analyzed 46 patients affected by CLL/MPN referred by 15 Italian GIMEMA centers. The aim of this retrospective multicenter study was to define the following: clinico-biological characteristics, possible familiarity, clinical course of both diseases, and influence of MPN chemotherapy on the course of CLL. Among 46 patients, 30 patients were males, 16 patients were females; median age was 71 years. Only one case had familiar CLL. Myeloproliferative disorders consisted of essential thrombocytemia in 18 cases, polycythemia vera in 10 cases, chronic myeloid leukemia in 9 cases, primary myelofibrosis in 6 cases, and MPN/myelodysplastic syndrome in 3 cases. The lymphoproliferative disorder was diagnosed as monoclonal B-cell lymphocytosis in 8 patients and as Binet Stage A CLL in 38 patients. After a median follow-up of 49 months, 9 patients experienced progressive CLL and only 6 patients required treatment after a median of 57.5 months. The biological profile confirmed a subset of low-risk CLL. Twenty patients received chemotherapy for MPN without influence on the course of CLL: lymphocyte counts remained unchanged after 3, 6, and 12 months of treatment. This series is the largest so far reported in literature. The diagnosis of concomitant CLL/MPN is a rare event and lymphoproliferative disorders present a clinical indolent course with a low-risk biological profile. MPN therapy does not interfere with the prognosis of patients with CLL.

[Prognostic markers in chronic lymphocytic leukemia]

Chronic lymphocytic leukemia is the most common leukemia type in Western countries. Even incidence of chronic lymphocytic leukemia is high, this disease remained beyond interest for a very long time. However, in the last few years the view of this disease fundamentally changed and due to intensive study, new knowledge especially on pathogenesis, prognostic factors and therapy based on intensive therapeutic procedures were made. Today we know that usage of classical prognostic factors is insufficient for prognosis evaluation in the individuals. However modern (IgVH mutation status, cytogenetic abberations) and new markers (LPL/ADAM29 ratio, microRNA, markers of angiogenesis etc) have potential to distinguish patients in early stages to groups with significantly different prognosis and predict clinical course of the disease.

Prolonged progression-free survival in patients with chronic lymphocytic leukemia receiving granulocyte colony-stimulating factor during treatment with fludarabine, cyclophosphamide, and rituximab

The clinical benefit of the addition of granulocyte colony-stimulating factor (G-CSF) to standard immunochemotherapy of chronic lymphocytic leukemia (CLL) with fludarabine, cyclophosphamide, and rituximab (FCR) is still unclear. In this retrospective study we analyzed the outcome of 32 consecutive patients with CLL during treatment with FCR. Sixteen patients received G-CSF for treatment of CTC grade 3 or 4 neutropenia or febrile neutropenia at some point during therapy and 16 did not. Both groups were well balanced for clinical and biological risk factors. Overall response rates were not significantly different (94% vs. 75%; p=0.144). Interestingly, a significantly better progression-free survival (100% vs. 35.4% at 24 months; p<0.001) and even overall survival (100% vs. 77.8% at 24 months; p=0.022) was observed in patients receiving G-CSF. While the underlying cause remains to be elucidated, these data strongly suggest an association of the addition of G-CSF to FCR therapy with final patient outcome.

Morphometric angiogenesis parameters for indolent and aggressive non-Hodgkin's lymphoma

There is much evidence about importance of angiogenesis in development and progression of solid tumors. The role of angiogenesis, as an indicator of higher malignant potential in non-Hodgkin's lymphoma, is not clear at the moment. Morphometric characteristics of microvessels in lymph node sections, in previously untreated patients with small lymphocytic lymphoma/chronic lymphocytic leukemia (SLL/CLL) and diffuse large B-cell lymphoma (DLBCL), were studied and relationship between angiogenesis and histological malignancy grade of NHL was also evaluated. Lymph node biopsies samples of 30 newly diagnosed patients with SLL/CLL (n=30) and DLBCL (n=30) were studied. All samples were fixed in 10% buffered formalin solution and embedded in paraffin. Microvessels were visualized by immunohistochemical staining for anti F-8 antibody. In the area showing the most intense vascularization (i.e. the "hot spot"), microvessel density (MVD), total vascular area (TVA), as well as the size related parameters were estimated, by using image analysis program "analysSIS'. Number and size-related microvessels angiogenic morphometric parameters were statistically higher in group with DLBCL compared with SLL/CLL: MVD (p = 0.002), TVA (p < 0.0001), area (p < 0.0001), perimeter (p < 0.0001), minor axis length (p < 0.0001) and major axis length (p < 0.0001). It is to be noted that positive correlation existed between TVA and MVD in DLBCL and SLL/CLL. The present study supports the view that angiogenesis correlate with histological grade of NHL.

Chronic lymphocytic leukemia: insights from lymph nodes & bone marrow and clinical perspectives

B-cell chronic lymphocytic leukemia (B-CLL) is characterized by highly variable distribution of tumor mass between peripheral blood, bone marrow and lymphoid organs which is important for staging, classification and prognosis. These clinical findings with novel data about importance of B-cell receptor and its stimulation with the support of microenvironment indicate important role of tissues (lymphoid organs and bone marrow) in the pathogenesis of B-CLL. Here is presented the novel approach of simultaneous characterization of B-CLL cells form peripheral blood, bone marrow and lymph nodes by flow cytometry and immunocytochemistry, defining inter- and intraclonal diversity with respect to various molecules. These include adhesion molecules (integrins, immunoglobulins, selectins), chemokine receptors (including CXCR-4), signaling molecules and prognostic factors (CD38 and ZAP-70), proliferation and apoptosis markers (including Ki67, AgNORs with PK index, survivin, bcl-2) and therapeutic targets (CD20 and CD52) and residual hematopoietic stem cells. A number of interesting significant interactions have been discovered, pointing to the important role of neoplastic cell microenvironment. These may in addition to insights in pathogenesis and roles of different microenvironments add to diagnosis, prognosis and treatment of B-CLL patients.

American Society of Hematology--51st annual meeting & exposition. Part 1

The 51st American Society of Hematology (ASH) Annual Meeting and Exposition, held in New Orleans, included topics covering new therapeutic developments in the field of hematology. This conference report highlights selected presentations on hematological malignancies, lymphoma, Hodgkin lymphoma, AKT inhibitors for the treatment of chronic lymphocytic leukemia, and the activation of GPIb with von Willebrand factor. Investigational drugs discussed include conatumumab (Amgen Inc/Takeda Bio Development Center Ltd) and A-443654 (Abbott Laboratories).

How I treat CLL up front

Although chronic lymphocytic leukemia (CLL) remains incurable, over the past decade there have been major advances in understanding the pathophysiology of CLL and in the treatment of this disease. This has led to greatly increased response rates and durations of response but not yet improved survival. Advances in the use of prognostic factors that identify patients at high risk for progression have led us to the question whether there is still a role for a "watch and wait" approach in asymptomatic high-risk patients or whether they should be treated earlier in their disease course. Questions remain, including, what is the optimal first-line treatment and its timing and is there any role of maintenance therapy or stem cell transplantation in this disease? CLL is a disease of the elderly and not all patients are eligible for aggressive up-front chemoimmunotherapy regimens, so what is the optimal treatment approach for more frail elderly patients? It is highly likely that our treatment approaches will continue to evolve as the results of ongoing clinical trials are released and that further improvements in the outcome of this disease will result from identification of therapies that target the underlying pathophysiology of CLL.

From pathogenesis to treatment of chronic lymphocytic leukaemia

Chronic lymphocytic leukaemia (CLL) has several unique features that distinguish it from other cancers. Most CLL tumour cells are inert and arrested in G0/G1 of the cell cycle and there is only a small proliferative compartment; however, the progressive accumulation of malignant cells will ultimately lead to symptomatic disease. Pathogenic mechanisms have been elucidated that involve multiple external (for example, microenvironmental stimuli and antigenic drive) and internal (genetic and epigenetic) events that are crucial in the transformation, progression and evolution of CLL. Our growing understanding of CLL biology is allowing the translation of targets and biological classifiers into clinical practice.

Disease-related anemia in chronic lymphocytic leukemia is not due to intrinsic defects of erythroid precursors: a possible pathogenetic role for tumor necrosis factor-alpha

BACKGROUND/AIMS

Disease-related anemia in chronic lymphocytic leukemia (CLL) occurs when the obvious causes are excluded while its pathogenesis is still obscure. We investigated its underlying mechanisms in 56 untreated patients with CLL.

METHODS

Bone marrow (BM) lymphocytic infiltration was estimated in trephine biopsies. Serum erythropoietin (EPO) and tumor necrosis factor-alpha (TNF-alpha) levels were measured by ELISA. The potential of BM CD34+ to differentiate into erythroid cells was evaluated by methylcellulose-based assays and in liquid cultures supplemented with EPO, SCF, IL-3 +/- TNF-alpha. The response of erythroid precursors to EPO +/- TNF-alpha was assessed by detecting activated key proteins of EPO-EPO receptor signalling pathway using Western Blot and EMSA.

RESULTS

Bone marrow lymphocytic infiltration was not exclusively responsible for disease-related anemia and CD34+ cells were intrinsically capable of generating erythroid precursors. Also, no deficiency of serum erythropoietin (EPO) or defective intracellular response of erythroid precursors to EPO +/- TNF-alpha stimulation was observed. Serum TNF-alpha levels were found increased in anemic CLL patients and TNF-alpha appeared to directly inhibit the erythroid development in early stages of erythropoiesis.

CONCLUSION

We concluded that CLL-related anemia was not due to intrinsic defects of erythroid precursors, but might result from the direct suppressive effect of TNF-alpha on the erythroid production.

CD40 ligand, Bcl-2 and apoptosis in B-chronic lymphocytic leukemia

Chronic lymphocytic leukemia (CLL) is a haematopoetic neoplasm caused primarily by defects in apoptosis mechanisms and complicated by progressive marrow failure, immunosupression and increased resistance to chemotherapy. The CD40-CD40 ligand (CD40L) interaction has been shown to significantly increase antigen presentation in normal and malignant B-cells and it is a powerful regulator of cell survival. Bcl-2 expression is common in CLL and is associated with decreased overall survival. Our objective was to asses CD40 ligand (CD154) and Bcl-2 expressions and their correlation with clinical and laboratory features in CLL patients. This study was conducted on 40 subjects, including 10 healthy volunteers as the control group and 30 patients presented with de novo chronic lymphocytic leukemia (CLL), all of them were subjected to thorough history taking, full clinical examinations, routine laboratory investigations and flowcytometric assessment of CD40L and Bcl-2 on lymphocytes. There was a highly significant increase in TLC, absolute lymphocytic count, serum LDH, B2-microglobulin and Bcl-2 expression (P<0.001); there was a significant increase in CD40L expression (P<0.05); whereas there was a highly significant decrease in hemoglobin concentration and platelets count between the study group (P<0.001). There was no significant difference as regard direct Coombs' test between both groups. There was no significant relation between CD154 expression and clinical findings, Rai staging system and other laboratory parameters. CD40L expression is increased with staging of Modified Rai staging system but not reaching the significant level. There was no significant correlation between CD154 expression and some of clinical and laboratory parameters, whereas there was only significantly negative correlation between Bcl-2 expression and both haemoglobin concentration and platelets count (P<0.001). Combination of Bcl-2 antisense oligonucleotide with conventional chemotherapeutic drugs may enhance the cytotoxicity of these drugs and induces apoptosis.

[Chronic lymphocytic leukemia]

Chronic lymphocytic leukemia results from a proliferation/accumulation of monoclonal B lymphocytes. The diagnosis is easily made on blood cytology and immunophenotype. The complexity of mechanisms which govern the clonal evolution translate in a large pronostic diversity on long-term outcome, with a life expectancy ranging from a few years to more than 25 years in the most indolent forms. Prognostic appraisal is currently based on clinical and hematological presentation, whereas cytogenetics, immunoglobulin gene status, expression of proteins involved in cell proliferation such as ZAP70 or CD38 provide more precise but non routine indications. Although there is a lot of effective drugs against the clonal process, any of them are curative, and long term benefit of treatment tailored on individual prognostic features still deserves further studies. Therefore, current treatment recommendations aim at sustaining quality of life in elderly patients, whereas response quality and length are the main targets in younger ones.

Antibody therapy for chronic lymphocytic leukemia

The introduction of the monoclonal antibodies rituximab (anti-CD20) and alemtuzumab (anti-CD52) has revolutionized the treatment of chronic lymphocytic leukemia (CLL). Both antibodies were first studied as single agents in relapsed CLL, but rituximab is increasingly used in combination chemoimmunotherapy regimens in previously untreated patients. Phase II studies demonstrated that the addition of rituximab to fludarabine-based chemotherapy improves complete response (CR) rates and prolongs progression-free survival (PFS), but a long-term survival benefit has not been shown. Alemtuzumab is less commonly used, due to the greater likelihood of infusion toxicity, as well as hematologic and immune toxicities. Subcutaneous (SC) administration significantly reduces infusion toxicity, but hematologic and infectious complications, most notably cytomegalovirus (CMV) reactivation, still occur with SC dosing. Alemtuzumab's unique clinical properties include its clinical activity in relapsed CLL patients with del(17p13) and its ability to eradicate minimal residual disease (MRD) in bone marrow. Its use as consolidation therapy to eradicate MRD after nucleoside analog therapy is under active study. Several investigational monoclonal antibodies are in preclinical or clinical studies, most notably lumiliximab (anti-CD23) and ofatumumab (HuMax CD20), and are briefly discussed in this review.

Chronic lymphocytic leukaemia

Chronic lymphocytic leukaemia is the commonest form of leukaemia in Europe and North America, and mainly, though not exclusively, affects older individuals. It has a very variable course, with survival ranging from months to decades. Major progress has been made in identification of molecular and cellular markers that could predict disease progression in patients with chronic lymphocytic leukaemia. In particular, the mutational profile of immunoglobulin genes and some cytogenetic abnormalities are important predictors of prognosis. However, these advances have raised new questions about the biology, prognosis, and management of chronic lymphocytic leukaemia, some of which are addressed here. In particular, we discuss how better understanding of the function of the B-cell receptor, the nature of genetic lesions, and the balance between proliferation and apoptosis have affected our ability to assess prognosis and to manage chronic lymphocytic leukaemia. Available treatments generally induce remission, although nearly all patients relapse, and chronic lymphocytic leukaemia remains an incurable disease. Advances in molecular biology have enhanced our understanding of the pathophysiology of the disease and, together with development of new therapeutic agents, have made management of chronic lymphocytic leukaemia more rational and more effective than previously. Unfortunately, we know of no way that chronic lymphocytic leukaemia can be prevented. Early detection is practised widely, but seemingly makes no difference to the patient's eventual outcome.

Immunophenotypic characterization of the leukemic B-cells from Iranian patients with chronic lymphocytic leukemia: association between CD38 expression and disease progression

BACKGROUND

Patients with B-cell chronic lymphocytic leukemia (B-CLL) have heterogeneous clinical courses, thus several biological parameters need to be added to the current clinical staging systems to predict disease outcome. Recent immunophenotypic studies performed mainly in Western populations have demonstrated the prognostic value of CD38 and ZAP-70 expression in B-CLL.

OBJECTIVES

To investigate the expression pattern of a variety of membrane antigens on leukemic cells from Iranian patients with CLL and to find out if there are any differences in the expression of these markers between indolent and progressive groups.

METHODS

In the present study, peripheral blood samples from 87 Iranian patients with B-CLL were analysed by flow cytometry.

RESULTS

In all cases, the neoplastic cells displayed B-CLL phenotype (CD5+/CD19+/sIg+). The vast majority of the cases expressed CD23, but failed to stain for CD3 or CD14. The leukemic cells of most patients expressed CD27 (84/87, 95.4%) and CD45RO (74/87, 83.9%) molecules, suggesting a memory B-cell phenotype. Comparison between the indolent (n=42) and progressive (n=37) patients revealed significantly higher frequency and intensity of CD38 expression in progressive group (40.5%) compared to indolent (11.9%) patients (p<0.05). None of the other membrane antigens were differentially expressed in these two groups of patients.

CONCLUSION

Our results obtained in an Asian ethnic population confirm and extend previous findings obtained from Western populations regarding the association of CD38 expression and disease progression in B-CLL.

Clinical and molecular predictors of disease severity and survival in chronic lymphocytic leukemia

Several parameters may predict disease severity and overall survival in chronic lymphocytic leukemia (CLL). The purpose of our study of 190 CLL patients was to compare immunoglobulin heavy chain variable region (IgV(H)) mutation status, cytogenetic abnormalities, and leukemia cell CD38 and Zap-70 to older, traditional parameters. We also wanted to construct a simple, inexpensive prognosis score that would significantly predict TTT and survival in patients at the time of diagnosis and help practicing clinicians. In univariate analyses, patients with higher clinical stage, higher leukocyte count at diagnosis, shorter leukocyte doubling time, elevated serum lactate dehydrogenase (LDH), unmutated immunoglobulin heavy chain variable region (IgV(H)) genes, and higher CD38 had a shorter overall survival and time-to-treatment (TTT). CLL cell Zap-70 expression was higher in patients with unmutated IgV(H), and those with higher Zap-70 tended to have shorter survival. IgV(H)4-34 or IgV(H)1-69 was the most common IgV(H) genes used (16 and 12%, respectively). Of those with IgV(H)1-69, 86% had unmutated IgV(H) and had a significantly shorter TTT. A cytogenetic abnormality was noted in 71% of the patients tested. Patients with 11q22 del and 17p13 del or complex abnormalities were significantly more likely to have unmutated IgV(H). We found that a prognostic score constructed using modified Rai stage, cellular CD38, and serum LDH (parameters easily obtained clinically) significantly predicted TTT and survival in patients at the time of diagnosis and performed as well or better than models using the newer markers.

Cell proliferation and death: forgotten features of chronic lymphocytic leukemia B cells

Chronic lymphocytic leukemia (CLL) results from an accumulation of abnormal B cells due to an imbalance between birth and death rates such that the former exceeds the latter. This imbalance can occur as a result of increased birth, decreased death, or a combination of the two. CLL has long been considered a disease in which cell accumulation results from decreased death, due to a genetic defect, with minimal birth of the leukemic clone. This view was promulgated when experimental options were limited and observations in vivo and in vitro were less precise--e.g. CLL cells appeared as resting lymphocytes by light microscopy and responded poorly to mitogens (primarily T-cell mitogens)--at a time when T- and B-cell discrimination was not well appreciated. However, recent studies using more sophisticated measures suggest that the initial characterization of CLL biology needs re-evaluation. Using a safe, non-radioactive in-vivo labeling method that permits the determination of CLL-cell birth rates, we have directly documented that a small fraction of the clone (approximately 0.1-1.75%), i.e., between approximately 1x10(9) and 1x10(12) cells are born each day in all patients studied. With this value, we calculated death rates of between 0 and 1x10(12) per day of leukemic cells from individual patients. Thus the dynamic interplay between birth and death that characterizes other leukemias and lymphomas applies to CLL. Therefore, CLL is a disease of both proliferation and accumulation in which a homeostatic balance exists in patients with stable lymphocyte counts or an imbalance exists in patients with rising lymphocyte counts.

HLA-G in B-chronic lymphocytic leukaemia: clinical relevance and functional implications

HLA-G appears to be involved in regulatory functions counteracting the cellular immune response of T and NK cells by several pathways. We here summarize the HLA-G expression patterns in leukaemia with emphasis on the clinical relevance of this expression for disease progression. Especially in patients with B-chronic lymphocytic leukaemia (B-CLL) the HLA-G expression on B-CLL cells was strongly associated with a reduced treatment-free survival. The corresponding immunological parameters point to a broad immunosuppression in these patients. Thus, HLA-G seems to contribute to the impaired immune response in B-CLL supporting disease progression.

CD39 activity correlates with stage and inhibits platelet reactivity in chronic lymphocytic leukemia

Background

Chronic lymphocytic leukemia (CLL) is characterized by accumulation of mature appearing lymphocytes and is rarely complicated by thrombosis. One possible explanation for the paucity of thrombotic events in these patients may be the presence of the ecto-nucleotidase CD39/NTDPase-1 on the surface of the malignant cells in CLL. CD39 is the major promoter of platelet inhibition in vivo via its metabolism of ADP to AMP. We hypothesize that if CD39 is observed on CLL cells, then patients with CLL may be relatively protected against platelet aggregation and recruitment and that CD39 may have other effects on CLL, including modulation of the disease, via its metabolism of ATP.

Methods

Normal and malignant lymphocytes were isolated from whole blood from patients with CLL and healthy volunteers. Enzyme activity was measured via radio-TLC assay and expression via FACS. Semi-quantititative RT-PCR for CD39 splice variants and platelet function tests were performed on several samples.

Results

Functional assays demonstrated that ADPase and ATPase activities were much higher in CLL cells than in total lymphocytes from the normal population on a per cell basis (p-value < 0.00001). CD39 activity was elevated in stage 0–2 CLL compared to stage 3–4 (p < 0.01). FACS of lymphocytes demonstrated CD39 expression on > 90% of normal and malignant B-lymphocytes and ~8% of normal T-lymphocytes. RT-PCR showed increased full length CD39 and splice variant 1.5, but decreased variant 1.3 in CLL cells. Platelet function tests showed inhibition of platelet activation and recruitment to ADP by CLL cells.

Conclusion

CD39 is expressed and active on CLL cells. Enzyme activity is higher in earlier stages of CLL and decreased enzyme activity may be associated with worsening disease. These results suggest that CD39 may play a role in the pathogenesis of malignancy and protect CLL patients from thrombotic events.

[Angiogenesis in the bone marrow of patients with chronic lymphocytic leukaemia]

Angiogenesis is a process of formation of new vessels from the preexisting ones. It is involved in many physiological processes, at the same time, however, it is involved also in the progress of tumoral growth. Although a lot is known about angiogenesis in solid tumors where it plays a role in tumoral invasion and its metastatic potential, in hematological malignancies it has been appreciated only recently. However, the results of studies on abnormal angiogenesis in hematological malignancies are inconsistent. Angiogenesis can be studied at different levels; histologically, it is studied in the infiltrated tissues (lymph nodes, bone marrow) and quantified as microvessel density (MVD). The aims of our study were to introduce the method of MVD quantification in the bonemarrow using immunohistochemical detection of endothelial markers (fVIII) and then evaluate MVD in bone marrow samples in a group of patients with chronic lymphocytic leukaemia (CLL) and compare the results with a control group of patients (CON). CLL is a typical malignancy of the hematopoietic tissue but the course and the prognosis of patients with this disease vary considerably. For this reason there is urgent need for novel prognostic markers in order to assess individual patient prognosis and tailor treatment. Angiogenesis is one of the possible markers which may add more informations about the course of this disease. So far only few studies have been published about angiogenesis measured as MVD in CLL patients andthe results are inconsistent. In our study, both the number and the area of microvessels were increased in bone marrow of patients with CLL, but the number and area of sinuses were not. It can be concluded that there are signs of abnormal angiogenesis in bone marrow of patients with CLL but larger study with longer follow-up is needed to give more specific information about prognostic value of these findings.

Health-related quality of life in younger patients with chronic lymphocytic leukemia treated with fludarabine plus cyclophosphamide or fludarabine alone for first-line therapy: a study by the German CLL Study Group

PURPOSE

To date, only a few studies have evaluated the health-related quality of life (HRQOL) of patients with chronic lymphocytic leukemia (CLL) receiving chemotherapy. Therefore, the German CLL Study Group assessed HRQOL in younger patients with advanced CLL receiving first-line chemotherapy with fludarabine or fludarabine plus cyclophosphamide (FC).

PATIENTS AND METHODS

Three hundred seventy-five patients younger than 66 years with advanced CLL were randomly assigned to receive either fludarabine alone (fludarabine 25 mg/m2/d for 5 days intravenously [IV], repeated every 28 days) or FC (fludarabine 30 mg/m2/d for 3 days IV plus cyclophosphamide 250 mg/m2/d for 3 days, repeated every 28 days). Six courses of treatment were planned to be administered. The European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire C30 was sent to all patients at baseline and after 6, 12, and 24 months.

RESULTS

Eighty-nine percent of 362 included patients completed at least one questionnaire (163 fludarabine- and 158 FC-treated patients). Comparing the baseline levels of 249 CLL patients with the general German population, significant differences in nearly all HRQOL scales were assessed between the two groups. A multivariate analysis showed no significant differences in all HRQOL scales between both arms. In both treatment arms, symptoms such as fatigue, insomnia, and appetite loss improved to lower levels after the end chemotherapy. Except for lower physical status, no significant difference in HRQOL between male and female patients was evaluated.

CONCLUSION

Fludarabine-based treatment seems to improve HRQOL little to moderately in younger patients with advanced CLL. No significant difference between fludarabine- and FC-treated patients was observed.

Indications for allogeneic stem cell transplantation in chronic lymphocytic leukemia: the EBMT transplant consensus

The aim of this project was to identify situations where allogeneic stem cell transplantation (allo-SCT) might be considered as a preferred treatment option for patients with B-cell chronic lymphocytic leukemia (CLL). Based on a MEDLINE search and additional sources, a consented proposal was drafted, refined and approved upon final discussion by an international expert panel. Key elements of the consensus are (1) allo-SCT is a procedure with evidence-based efficacy in poor-risk CLL; (2) although definition of 'poor-risk CLL' requires further investigation, allo-SCT is a reasonable treatment option for younger patients with (i) non-response or early relapse (within 12 months) after purine analogues, (ii) relapse within 24 months after having achieved a response with purine-analogue-based combination therapy or autologous transplantation, and (iii) patients with p53 abnormalities requiring treatment; and (3) optimum transplant strategies may vary according to distinct clinical situations and should be defined in prospective trials. This is the first attempt to define standard indications for allo-SCT in CLL. Nevertheless, whenever possible, allo-SCT should be performed within disease-specific prospective clinical protocols in order to continuously refine transplant indications according to new developments in risk assessment and treatment of CLL.