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Recent research has shown that chronic lymphocytic leukemia (CLL) B-cells display a strong tendency to differentiate into antibody-secreting cells (ASCs) and thus may be amenable to differentiation therapy. However, the effect of this differentiation on factors associated with CLL pathogenesis has not been reported. In the present study, purified CLL B-cells were stimulated to differentiate into ASCs by phorbol myristate acetate or CpG oligodeoxynucleotide, in combination with CD40 ligand and cytokines in a two-step, seven-day culture system. We investigated (i) changes in the immunophenotypic, molecular, functional, morphological features associated with terminal differentiation into ASCs, (ii) the expression of factors involved in CLL pathogenesis, and (iii) the expression of pro- and anti-apoptotic proteins in the differentiated cells. Our results show that differentiated CLL B-cells are able to display the transcriptional program of ASCs. Differentiation leads to depletion of the malignant program and deregulation of the apoptosis/survival balance. Analysis of apoptosis and the cell cycle showed that differentiation is associated with low cell viability and a low rate of cell cycle entry. Our findings shed new light on the potential for differentiation therapy as a part of treatment strategies for CLL.

We report our experience on bendamustine and rituximab (BR) combination in 26 patients with chronic lymphocytic leukemia (CLL) complicated by autoimmune hemolytic anemia (AIHA). At the time of BR initiation, 88% of the patients had already been treated for AIHA and CLL was progressive regardless of AIHA in all patients but one. Overall response rates were 81% for AIHA and 77% for CLL. Median time to next treatment was 28.3 months and 26.2 months for AIHA and CLL, respectively. BR therapy may represent a good and safe therapeutic option in this setting where adequate control of CLL seems important for long-term AIHA response., (© 2014 Wiley Periodicals, Inc.)

In this study, we investigated the capacity of chronic lymphocytic leukemia (CLL) B cells to undergo terminal differentiation into Ig-secreting plasma cells in T cell-independent and T cell-dependent responses. We used a two-step model involving stimulation with phorbol myristate acetate (PMA) and CD40L, together with cytokines (PMA/c and CD40L/c), for 7 days. We describe immunophenotypic modifications, changes in the levels of mRNA and protein for transcription factors and morphological and functional events occurring during the differentiation of CLL B cells into antibody-secreting cells (ASCs). The induction of differentiation differed significantly between the CD40L/c and PMA/c culture systems. The PMA/c culture system allowed CLL B cells to differentiate into IgM-secreting cells with an immunophenotype and molecular profile resembling those of preplasmablasts. By contrast, CD40L/c-stimulated cells had a phenotype and morphology similar to those of activated B cells and resembling those of the CLL B cells residing in the lymph node and bone marrow. These data suggest that the CLL B cells are not frozen permanently at a stage of differentiation and are able to differentiate into ASCs as appropriate stimulation are provided. The data presented here raise questions about the molecular processes and stimulation required for CLL B-cell differentiation and about the inability of CD40 ligand to induce differentiation of the CLL B cells.

B-chronic lymphocytic leukemia (B-CLL), the most common human leukemia, is characterized by predominantly non-dividing malignant mature CD5+ B lymphocytes with an apoptosis defect. Various microenvironmental stimuli confer a growth advantage on these leukemic cells and extend their survival in vivo. Nevertheless, when cultured in vitro, CLL B-cells rapidly die from apoptosis. Certain cytokines may extend the survival capacity of CLL B-cells in vitro and individual anti-apoptotic effects of several cytokines have been reported. The potential cumulative effect of such cytokines has not been studied. We therefore investigated the effects on CLL B-cells survival in vitro of humoral factors, polyclonal lymphocyte activators and a combination of cytokines known for their anti-apoptotic effects. Purified CLL B-cells were cultured in the presence or absence of various soluble molecules and the leukemic cell response was assessed in terms of viability. Apoptotic cell death was detected by flow cytometry using annexinV and 7-amino-actinomycin. The survival of CLL B-cells in vitro was highly variable. When tested separately, cytokines (IL-2, -6, -10, -12, -15, -21, BAFF and APRIL) improved CLL B cell survival moderately; in combination, they significantly enhanced survival of these cells, even up to 7 days of culture. We also report that humoral factors from autologous serum are important for survival of these malignant cells. Our findings support the concept that the CLL microenvironment is critical and suggest that soluble factors may contribute directly to the prolonged survival of CLL B-cells. Therefore, the combination of cytokines we describe as providing strong resistance to apoptosis in vitro might be used to improve the treatment of CLL.

A French and Belgian multicenter phase 3 trial was conducted in medically fit patients with untreated chronic lymphocytic leukemia. Of 178 patients enrolled in the study, 165 were randomly assigned to receive 6 courses of oral fludarabine and cyclophosphamide (FC) in combination with rituximab (FCR; 375 mg/m(2) in cycle one, 500 mg/m(2) in all subsequent cycles) or alemtuzumab (FCCam; 30 mg subcutaneously injected on cycle days 1-3); each cycle was 28 days. Recruitment was halted prematurely because of excess toxicity; 8 patients died in the FCCam group, 3 from lymphoma and 5 from in-fection. Overall response rates were 91% with FCR and 90% with FCCam (P = .79). Complete remission rates were 33.75% with FCR and 19.2% with FCCam (P = .04). Three-year progression-free survival was 82.6% with FCR and 72.5% with FCCam (P = .21). Three-year overall survival was similar between the 2 arms at 90.1% in the FCR arm and 86.4% in the FCCam arm (P = .27). These results indicate that the FCCam regimen for the treatment of advanced chronic lymphocytic leukemia was not more effective than the FCR regimen and was associated with an unfavorable safety profile, representing a significant limitation of its use. This study is registered with www.clinicaltrials.gov as number NCT00564512.

Background: Eosinophilic dermatosis of hematologic disease (EDH) or insect bite-like reaction is a pruritic dermatitis described mostly in patients with chronic lymphocytic leukaemia (CLL). We describe six patients with the disorder in association with CLL and other blood dyscrasias., Patients and Methods: We reviewed the medical records of patients with EDH seen between 2004 and 2009 in our department and re-examined histological slides., Results: Mean age at dermatosis onset was 75.6 years and the sex ratio was 1. There were three CLL, two mantle-cell lymphomas and one MALT-type lymphoma. The dermatitis was quite polymorphic, with erythematous papules, wheals and plaques. The initial skin lesions appeared at the same time as or after the diagnosis of haematological neoplasm. Their reappearance heralded relapse of the blood disease in three cases. Histologically, all lesions had a dense dermal infiltrate of small, mostly CD4+ T-cells, with numerous eosinophils. In three patients, there was marked folliculotropism, resembling folliculotropic T-cell lymphoma. In most cases, EDH disappeared after appropriate chemotherapy for the blood disorder., Discussion: Our cases show that the clinical expression of EDH is quite polymorphic. Its appearance may precede relapse of or may indicate prompt search screening for blood dyscrasia. The most efficient treatment of this dermatosis appears to be specific chemotherapy for the blood dyscrasia. There is reason to believe that a population of T-helper 2 (Th2) lymphocytes, reactive to malignant B-cells, induces tissue eosinophilia, mainly through production of interleukin (IL)-5, among other cytokines. Eosinophils appear to be the main effector cells., (Copyright 2010. Published by Elsevier Masson SAS.)

ZAP-70 and CD38 expression can identify B-cell chronic lymphocytic leukemia with an inferior clinical outcome. Many groups have investigated the meaning of the expression of these two proteins and the correlation with the bad prognosis in B-CLL. But nobody has investigated the relation between the multidrug resistance mediated by Pgp overexpression (MDR1) and ZAP-70/CD38 coexpression. Forty-one untreated and stage A patients, either ZAP-70(+)CD38(+) or ZAP-70(-)CD38(-), were tested to determine the MDR1 status. MDR1 was observed in 41% of CLL ZAP-70(+)CD38(+) and in 37% of CLL ZAP-70(-)CD38(-). The difference was not significant (p = 0.745). Patients with ZAP-70 and CD38 positive CLL can not be candidates for MDR1 antagonists.