Chronic lymphocytic leukemia: a changing natural history?

There are some data suggesting that the natural history of chronic lymphocytic leukemia (CLL) may be changing, but a systematic analysis of this topic is lacking. To address this issue, we examined two cohorts of CLL patients in whom the diagnosis was established in 1960-1979 (group I) and in 1980-1989 (group II), respectively. Striking differences were observed between both cohorts. The diagnosis in the second group was established at higher age (65.8 vs 61.3 years; P = 0.0001), both in males (63.8 vs 59.1 years; P = 0.004) and females (68.3 vs 64.2 years; P = 0.01); the proportion of patients in whom the diagnosis was established in low-risk clinical stage (Binet's A) was significantly higher in group II (65.7% vs 42.6%; P < 0.001), and the survival was more than double in group II (median of 11.1 vs 5.3 years; P < 0.0001). Moreover, the impact of the disease on life expectancy was much lower in the more recent cohort. These differences may be due, at least in part, to changes in the natural history of the disease.

Loss of functional cell surface transforming growth factor beta (TGF-beta) type 1 receptor correlates with insensitivity to TGF-beta in chronic lymphocytic leukemia

Chronic lymphocytic leukemia (CLL) is the most common form of adult leukemia in Western countries, and there is significant variability in survival within CLL clinical stages. Earlier studies showed that CLL cells produce and are usually growth inhibited by transforming growth factor beta type 1 (TGF-beta1), suggesting a mechanism for the clinically indolent course of most CLL. Here we studied the mechanism by which CLL cells from about one-third of the patients are insensitive to TGF-beta1. Of the 13 patients studied, CLL cells isolated from the peripheral blood of 8 patients were sensitive to growth inhibition by TGF-beta1, as determined by incorporation of tritiated thymidine, whereas those from 5 patients were completely resistant to TGF-beta1. As judged by binding of radiolabeled TGF-beta1 followed by cross-linking and immunoprecipitation with anti-receptor antisera, CLL cells sensitive to TGF-beta1 exhibited normal cell surface expression of both types 1 and 2 TGF-beta receptors. In contrast, all CLL cells resistant to TGF-beta1 exhibited no detectable surface type I receptors able to bind TGF-beta1, but normal expression of type II receptors. Both TGF-beta1-sensitive and TGF-beta1-resistant CLL cells contained normal amounts of both type 1 and type 2 receptor mRNAs. Specific loss of type 1 receptor expression represents a new mechanism by which cells acquire resistance to TGF-beta1-mediated growth inhibition in the development and progression of human lymphoproliferative malignancies.

Involvement of CED-3/ICE proteases in the apoptosis of B-chronic lymphocytic leukemia cells

B-chronic lymphocytic leukemia (B-CLL) is characterized by the accumulation of long-lived B lymphocytes that express high levels of Bcl-2. We examined the involvement of CED-3/ICE-like proteases in the apoptosis of B-CLL cells. One of the substrates of these proteases is poly(ADP [adenosine 5'-diphosphate]-ribose) polymerase (PARP). The effect of different factors that induce the apoptosis of B-CLL cells on the proteolytic cleavage of PARP has been studied. Treatment of B-CLL cells with different concentrations of dexamethasone (1 to 1,000 micromol/L) induced in a dose-dependent manner the cleavage of PARP. Dexamethasone induced PARP cleavage after 12 hours of incubation, which was almost complete at 48 hours. PARP cleavage during apoptosis of B-CLL cells was studied in cells from eight patients and a correlation was found between cell viability and the degree of PARP cleavage. Incubation in vitro of B-CLL cells with fludarabine for 48 hours induced PARP cleavage in all the cases studied. Protein kinase C (PKC) activation with 100 nmol/L TPA (12-O-tetradecanoylphorbol 13-acetate) or incubation with interleukin-4 (10 ng/mL) prevented either dexamethasone- or fludarabine-induced proteolysis of PARP. Incubation of B-CLL cells with the CED-3/ICE-like protease inhibitor Z-VAD.fmk inhibited spontaneous and dexamethasone-induced PARP cleavage and DNA fragmentation in a dose-dependent manner. Furthermore, Z-VAD.fmk prevented the cytotoxic effect of dexamethasone. These results indicate that CED-3/ICE-like proteases play an important role in the apoptosis of B-CLL cells.

Clinico-prognostic implications of increased levels of soluble CD54 in the serum of B-cell chronic lymphocytic leukemia patients. Results of a multivariate survival analysis

BACKGROUND AND OBJECTIVE

Although less specific than sCD23, sCD54 levels have clinico-prognostic relevance in B-cell chronic lymphocytic leukemia (CLL). Since serological markers are now emerging as potentially important in CLL, we tried to verify whether sCD54 might complement clinical stages.

METHODS

Serum levels of sCD54 were determined at the time of diagnosis in 115 previously untreated CLL patients. Results were correlated with clinicobiological parameters as well as with survival.

RESULTS

Life-expectancy was significantly shorter in patients with higher serum levels of sCD54 (p < 0.001); however, in a Cox's multivariate survival analysis, the only variables which entered the regression model at a significant level were bone marrow (BM) histology (p = 0.03) and lymphocyte doubling time (LDT) (p = 0.04). Interestingly, when LDT was excluded from analysis the only significant variables were clinical stages (p < 0.05) and sCD54 (p < 0.05). These results suggest that sCD54 and LDT give similar prognostic information.

INTERPRETATION AND CONCLUSIONS

In CLL, sCD54 is a reliable prognostic parameter whose value is independent of clinical stages. When investigated in relation to clinical outcome, serum levels of sCD54 were able to predict progression to a more advanced clinical stage. On the basis of these data, an integrated clinico-biological classification which separates intermediate risk into two prognostic subgroups is proposed.

Expression profile of MDM-2 proteins in chronic lymphocytic leukemia and their clinical relevance

The MDM-2 oncoprotein exists in an autoregulatory feedback loop with the tumor suppressor protein p53. Therefore, intracellular levels of these two proteins may play important roles in cell proliferation and tumorigenesis. Several MDM-2 proteins (Mr 35-100 Kd) have been demonstrated in human cell lines. We report here the expression profile of MDM-2 and p53 proteins in 87 cases of chronic lymphocytic leukemia (CLL) as detected by immunoblot analysis. The MDM-2 proteins (p57, p59, p67, and p90) were found to be overexpressed in different combinations in 56/87 (64%) of cases of CLL when compared with normal volunteers. The MDM-2 protein p57 was predominantly overexpressed 46/87 (53%) in CLL. In 22/87 (25%) cases of CLL p57 was overexpressed alone, and in 24/87 (28%) cases it was co-overexpressed with other MDM-2 proteins p59/p67/p90. Six of the 87 cases of CLL showed overexpression of the tumor suppressor protein p53 by immunoblot analysis, and five of those cases also co-overexpress MDM-2 protein p57. No statistically significant correlation of MDM-2 protein overexpression to clinical disease stage and history of previous chemotherapy of CLL patients has been found. However, considering the oncogenic potential of overexpressed MDM-2 proteins, a possible role of MDM-2 proteins in the promotion of CLL disease remains to be evaluated.

Chronic lymphocytic leukemia

B-cell chronic lymphocytic leukemia (B-CLL), the leukemia with highest incidence in Western Countries, is a neoplastic disease characterized by a progressive accumulation of functionally incompetent, long-lived small mature lymphocytes in the blood, bone marrow, and lymphoid tissues. B-CLL lymphocytes express characteristic low amounts of surface immunoglobulin and CD5 antigen. They are resistant to Epstein Barr Virus (EBV) transformation; are in prolonged G0 phase, express high amounts of bcl-2 and display a defective response to stimulation through the antigen receptor. Despite the presence of many genetic abnormalities, in CLL, there are no typical chromosomal aberrations or oncogenic abnormalities associated with this disease.

Cellular expression and serum circulating levels of CD23 in B-cell chronic lymphocytic leukemia. Implications for prognosis

BACKGROUND

CD23 is a functionally relevant molecule in B-cell chronic lymphocytic leukemia (CLL) which mediates growth and differentiation signals in B-cells. An intriguing feature of CD23 is its ability to be cleaved from the cell surface and released into the serum.

MATERIALS AND METHODS

Serum levels of soluble CD23 (sCD23) were determined with a sandwich enzyme immunoassay at the time of diagnosis in 90 previously untreated CLL patients, in order to evaluate whether they reflected disease activity and tumor load. Results were correlated with those dealing with CD23 expression on leukemic cells to verify whether the cellular counterpart determines serum levels.

RESULTS

CD23 was detected on peripheral blood mononuclear cells (PBMC) from 78 out of 90 (86.6%) B-CLL patients, without correlation with clinical stage. Circulating levels of sCD23 in the serum of patients with CLL were highly elevated in comparison to 15 normal controls (p < 0.0005); this increase reflected tumor mass as defined by either clinical stage (p < 0.0005) or bone marrow (BM) histology (p < 0.0005). Neither percentage nor absolute number of CD23+ cells correlated with circulating levels. Interestingly, life expectancy was significantly shorter in patients with higher serum levels of sCD23 (p < 0.0005). When integrated into the Binet clinical staging system, sCD23 led to isolation of two subgroups with different prognosis among intermediate-risk patients. Furthermore, longitudinal studies support the idea that sCD23 can be utilized as an indicator of disease progression.

CONCLUSIONS

sCD23 is a highly sensitive and suitable marker with prognostic potential in B-CLL.

Clinical significance of sIL2R, sCD23, sICAM-1, IL6 and sCD 14 serum levels in B-cell chronic lymphocytic leukemia

BACKGROUND

The aim of the study was to establish the role exerted by some soluble factors in B-CLL disease mechanisms.

MATERIALS AND METHODS

Serum levels of sIL2R, sCD23, sICAM-1, IL6 and sCD14 were detected in 47 B-CLL patients. Thirty-seven out of the 47 cases were in advanced/progressive stage, while the remaining 10 patients were defined as smouldering B-CLL. Twenty normal controls provided the reference values. Serum samples of 24 out 37 advanced/progressive cases were measured before and six months after the start of chemotherapy.

RESULTS

The advanced/progressive patients showed significantly higher levels of sIL2R, sICAM-1 and sCD23 as compared to normal subjects. Furthermore, sIL2R, sICAM-1 and IL6 values were significantly higher in advanced/progressive B-CLL than in smouldering B-CLL patients. A statistically significant difference was found between smouldering B-CLL and controls for sCD14 only. sIL2R and sICAM-1 levels directly correlated with total tumor mass (TTM) score, sCD23 with both TTM score and lymphocytosis, and sCD14 with IgG serum values. sIL2R and sCD23 levels lowered significantly after chemotherapy, but only sCD23 and TTM variations after chemotherapy were closely correlated.

CONCLUSIONS

sCD23 may be considered the only indicator of tumor mass, while the other soluble factors can be released through different mechanisms. In particular, sICAM-1 seems to correlate with the ability of the tumor to spread, while the sCD14 increase could indicate a role for this soluble factor in preventing infections in B-CLL patients.

Multiple myeloma and chronic lymphocytic leukemia

Much progress has been made in delineating the pathogenesis of multiple myeloma and chronic lymphocytic leukemia. The cell of origin in both diseases has been better defined, which has led to important clinical treatments. For myeloma, reduction of tumor burden in autografts has been accomplished and been associated with favorable outcome. The importance of interleukin-6 in maintaining this tumor and causing skeletal disease has been more clearly defined and has led to treatment with antibodies that block this cytokine's action. The bisphosphonate pamidronate decreases skeletal complications and improves quality of life for these patients. For chronic lymphocytic leukemia, further definition of common cytogenetic and gene abnormalities have been made and associated with patient outcome. The nucleoside analogues continue to produce excellent responses and the use of myeloablative chemotherapy with hematopoietic support shows promise in early studies.

Chronic lymphocytic leukaemia at a county hospital in southern Sweden

We have studied retrospectively patients with chronic lymphocytic leukaemia (CLL), at Ryhov, Jönköping, Sweden during a 10-year-period. This unselected cohort (n = 59) from a well-defined geographical area is suitable for describing the natural course of the disease. The CLL was diagnosed incidentally in the majority of cases. Median-age at diagnosis was 71 years and the male:female ratio was 1.3:1. The diagnosis was based on morphology in 66% and in 33% immunophenotyping specified the diagnosis of B- or T-CLL. At diagnosis 66% were in Rai-stage O/I or Binet-stage A. There were 36% untreated patients and their median-survival was 108 months compared with 84 months for the whole cohort and 72 months for the treated patients. Malignancies were seen in 31% and infections in 83%. Intercurrent diseases played an important role in the survival. During the observation time, only 54% of the deceased patients had died due to the CLL.

Chronic lymphocytic leukemia and the central nervous system: a clinical and pathological study

Chronic lymphocytic leukemia is the most common human leukemia but infrequently causes neurologic symptoms. We have reviewed all previously reported cases of chronic lymphocytic leukemia in the CNS along with three new cases; one patient was diagnosed antemortem and treated with immediate improvement and 4-year survival. In addition, we reviewed all autopsy cases since 1972 and available lumbar puncture data on patients with chronic lymphocytic leukemia admitted to the Massachusetts General Hospital. Invasion of the CNS by chronic lymphocytic leukemia often leads to confusional state, meningitis with cranial nerve abnormalities, optic neuropathy, or cerebellar dysfunction. Lumbar puncture shows a lymphocytosis consisting of monoclonal B cells, but CSF cytology studies are of limited value in establishing the diagnosis. Long-term survival may be related to the stage of chronic lymphocytic leukemia at the time of CNS disease and may be associated with intrathecal chemotherapy. A mild, asymptomatic infiltration of the brain, frequently noted in late-stage chronic lymphocytic leukemia in autopsy series, may explain the CSF lymphocytosis in some patients with late-stage chronic lymphocytic leukemia.

Role of accessory cells in cytokine production by T cells in chronic B-cell lymphocytic leukemia

We investigated the production of cytokines by highly purified T helper cells from B-cell chronic lymphocytic leukemia (B-CLL) patients stimulated by different activation pathways, and we studied the influence of various accessory cell populations on the pattern of the secretion of cytokines, including interleukin (IL)-2, IL-4, interferon-gamma (IFN-gamma), and IL-10. Neither a qualitative nor a quantitative difference in cytokine production and proliferative capacity was observed in CLL-derived purified T cells compared with normal individuals, when T cells were stimulated by different pathways, including CD3, CD2, and costimulation with CD28. Addition of autologous accessory cells (aAC), however, dramatically influenced the cytokine pattern of normal versus B-CLL-derived T cells. CLL cells as aAC caused a marked increase of IL-2, whereas IFN-gamma was only slightly induced and IL-4 was not influenced. In contrast, in normal individuals addition of aAC, which predominantly consisted of monocytes, resulted in a significant increase of IFN-gamma and a reduction of IL-4 secretion. IL-2 production was inhibited by higher concentrations of aAC. The increased stimulation of IL-2 production by CLL cells was not specific to the leukemic cell population, as purified B cells from normal individuals had the same effect. On the other hand, purified monocytes from CLL patients and controls both induced IFN-gamma production and inhibited IL-4 secretion. After antigen-specific stimulation with tetanus toxoid, cytokine secretion was influenced by the type of aAC in a similar pattern. We conclude that T helper cells derived from patients with B-CLL are intrinsically normal and that the predominance of B cells as accessory cells in CLL significantly alters the immune function of T helper cells in vitro.

Evidence for involvement of activated CD8+/HLA-DR+ cells in the pathogenesis of neutropenia in patients with B-cell chronic lymphocytic leukaemia

B-cell chronic lymphocytic leukaemia (B-CLL) is often associated with peripheral blood cytopenias resulting, in most cases, from bone marrow infiltration, hypersplenism, or circulating autoantibodies. The present study was undertaken to investigate the possible involvement of a cell-mediated suppression of granulopoiesis in these patients. We studied two groups of patients, 8 neutropenic and 26 non-neutropenic, defined by the arbitrarily taken cutoff count of 2000 neutrophils/microliters. We found that neutropenic patients had higher numbers of peripheral blood CD3+, CD8+ and CD57+ cells, and higher numbers of activated CD8+/HLA-DR+ cells than the non-neutropenic ones. A negative correlation between CD8+ cells and circulating neutrophils, and a suggested negative correlation between CD8+/HLA-DR+ cells and circulating neutrophils were noted in the patients studied. Furthermore, we investigated the capacity of immunomagnetically isolated CD8+ cells to inhibit in vitro colony formation by normal granulocyte/macrophage colony-forming units (CFU-GM) and we found that inhibition was more pronounced when CD8+ cells, added in the culture, were derived from neutropenic than from non-neutropenic patients. The degree of colony inhibition correlated with the number of circulating neutrophils and the numbers of CD8+ and CD8+/HLA-DR+ cells in the patients studied. Since tumour necrosis factor-alpha (TNF-alpha) has been reported to be involved in myelosuppression, we also investigated the capacity of isolated CD8+ cells to release this cytokine into the culture supernatant fluids, and we found that comparable amounts of TNF-alpha were produced after stimulation in both neutropenic and non-neutropenic patients. Elevated serum TNF-alpha concentrations were noted only in a number of neutropenic and non-neutropenic patients. All these data taken together provide strong evidence that a T-cell subpopulation of activated CD8+/HLA-DR+ cells may be involved in the pathogenesis of neutropenia, at least in a subset of B-CLL patients, suppressing myelopoiesis by a TNF-alpha-unrelated mechanism. Efforts to isolate this cell subpopulation by flow cytometry for further analysis and a better understanding of its effect on myelopoiesis in patients with B-CLL are in progress in our laboratory.

Defects in signal transduction pathways in chronic B lymphocytic leukemia cells

B chronic lymphocytic leukemia (B-CLL) and hairy cell leukemia (HCL) cells are refractory to many of the signals which activate normal B cells but are stimulated to proliferate by tumor necrosis factor (TNF). Cell signalling by TNF is mediated in part by the induction of the transcription factor families AP-1 and NF-kappa B. In some cellular contexts, these factors play a role in regulating cell cycle transit. AP-1 binds DNA as dimers of jun and fos family proteins and is regulated by a cascade of protein kinases which eventually activate a mitogen-activated protein kinase (MAP kinase) and also by protein kinase C. Three pathways have been implicated in the activation of NF-kappa B by extracellular ligands. 1, the activation of protein kinase C by diacylglycerol generated by ligand-mediated activation of phosphatidylcholine hydrolysis, 2, stimulation of specific protein kinases by ceramide generated following activation of a sphingomyelinase by diacylglycerol and 3, a novel pathway involving ligand-induced generation of free radical species. In B-CLL and HCL cells, the generation of nuclear-localized c-jun and c-fos proteins (components of AP-1) in response to TNF or PMA appears to be blocked. Whereas PMA failed to induce NF-kappa B in these cells, this factor was readily induced by TNF. TNF induction of NF-kappa B was abolished by antioxidants, suggesting involvement of the free radical pathway. The data discussed here suggest defects in coupling of some protein kinase C-dependent pathways in B-CLL and HCL cells and that TNF is able to bypass these blocks by the activation of NF-kappa B via a free radical-dependent pathway which is independent of protein kinase C.(ABSTRACT TRUNCATED AT 250 WORDS)

Small cell pleomorphic T-cell lymphoma presenting with cutaneous vasculitis

The association between cutaneous vasculitis and lymphoproliferative disease has been increasingly recognized. We report a female patient who presented with cutaneous vasculitis which was due to a small cell pleomorphic T-cell lymphoma. In spite of aggressive therapy, she died two years after onset of disease. The clinical picture of vasculitis associated with lympho-proliferative disease is addressed with particular emphasis on symptoms and signs suggesting malignancy rather than vasculitis appearing in concert with well-defined connective tissue disorders.

Chronic lymphocytic leukemia and hairy-cell leukemia

In recent years, major advances in our understanding of the biology of the chronic lymphoid leukemias have been accompanied by the emergence of new therapeutic options. Chronic lymphocytic leukemia, the most common of these disorders, appears to be related to a failure of apoptosis, leading to accumulation of functionally abnormal lymphocytes. Fludarabine, a nucleoside analogue that may activate apoptosis, has emerged as the most effective agent for newly diagnosed as well as relapsed patients with chronic lymphocytic leukemia. Nevertheless, few if any patients are cured with this agent. Unique chemotherapeutic and biologic therapies are being explored, and new strategies combining several approaches will likely be established. For patients with hairy-cell leukemia, pentostatin and 2-chlorodeoxyadenosine achieve durable complete remissions in 65% to 85% of patients, with comparable toxicity.

Comparison of younger versus older B-cell chronic lymphocytic leukemia patients for clinical presentation and prognosis. A retrospective study of 53 cases

Fifty-three patients affected with B-cell chronic lymphocytic leukemia (CLL) younger than 50 years and observed in two hematological institutions have been retrospectively evaluated in order to verify whether this disease has different clinico-hematological features at presentation and different prognosis as compared to older cases. In our experience young cases with B-CLL diagnosis, confirmed by immunophenotype in 90.5% of patients, accounted for 7.1% of the whole CLL population. Sex distribution, mean peripheral lymphocyte count, platelet count, distribution among Rai's and Binet's stages, total tumor mass (TTM) score, histological pattern of bone marrow infiltration and lymphocyte doubling time (LDT) were similar to a series of 201 CLL cases older than 50 years. Only hemoglobin mean level was significantly higher in younger patients (13.1 +/- 2.1 vs 12.2 +/- 2.6 g/dl; p < 0.01). The overall median survival was 7.1 years. Rai and Binet staging classifications and TTM score system retained their prognostic value in this CLL population. In addition, cases fulfilling criteria of "smoldering" CLL, had a very long survival (75% survival probability at 16 years). Life-expectancy of younger patients was significantly longer than that of older ones (median survival, 7.1 versus 4.1 years; p < 0.05). However, when the background mortality due to non-CLL related deaths (i.e., cardiovascular complications, epithelial cancers) was removed, survival advantage of young cases disappeared. In conclusion this study confirms that prognosis of young CLL patients can be easily assessed using the current well-defined criteria. Since age is not by itself a criterion for intensifying treatment, further efforts to identify those young CLL patients who qualify for more aggressive therapy should be made.

Chronic lymphocytic leukemia: a retrospective study of 122 cases

During the period 1978-1982 in the three northernmost countries of Sweden all 143 patients with a registered diagnosis of chronic lymphocytic leukemia (CLL) were retrospectively analyzed. After re-evaluation, 122 cases remained in the study. The mean age was 71 years and the male/female ratio was 2.2:1. Sixty-one patients were Binet stage A, 29 stage B and 32 stage C. The diagnosis CLL was made after routine check-up for other diseases in most of the patients and they had no symptoms from the CLL. The median survival was 51 months and there were no differences in crude survival according to stage or other prognostic factors such as hemoglobin, lymphocytes or thrombocytes in peripheral blood. Analysis of CLL as a cause of specific mortality showed the stage of CLL to have a slight prognostic significance. This could be due to the fact that many of the patients suffered from other serious diseases, allowing the detection of early stage or advanced CLL with no symptoms.

Chemomodulation of drugs involved in multidrug resistance in chronic lymphatic leukemia of the B-cell type

Reduced drug accumulation may be one reason for intrinsic drug resistance in chronic lymphatic leukemia of the B-cell type (B-CLL). Immunophenotyped leukemic human B-cells from 38 cases of B-CLL were characterized for P-glycoprotein (PGP) content. In all, 30 cases of B-CLL were additionally analyzed for further parameters: accumulation of daunorubicin (DNR, n = 20) and rhodamine 123 (Rh123, n = 30) in both the presence and the absence of verapamil (VRP). Also, 16 cases of B-CLL were analyzed for vincristine (VCR) accumulation with or without VRP. Concerning the relative expression of PGP, these 16 cases of B-CLL were representative for the whole group of 30 cases. Spontaneous accumulation of Rh123 and VCR varied over a wide range: accumulation of Rh123, by a factor of 11.8; accumulation of VCR, by a factor of 9.7; and accumulation of DNR, by a factor of 3.6. VRP modulated the accumulation of RH123 in 16/30 cases (53%), that of VCR in 69% of cases, and that of DNR in 11% of cases. The maximal VRP-mediated increases in accumulation amounted to factors of 1.3 for DNR, 2.3 for Rh123, and 7.8 for VCR. Spontaneous drug accumulation did not correlate with the extent of chemomodulation. The amount of PGP in B-CLL cells (all cases studied were PGP-positive) did not correlate with drug accumulation or with the extent of VRP-mediated chemomodulation. Thus, high expression of PGP is only partially responsible for defective drug accumulation in B-CLL. Only the degree of chemomodulation by VRP is predictive for the extent of the PGP-related functional drug accumulation defect. Thus, in B-CLL, PGP-independent drug accumulation defects seem to be as important as those mediated by PGP. The extent of this drug accumulation defect varies for the different drugs in the following order VCR > Rh123 > DNR. The relevance of PGP-mediated and -independent drug accumulation defects in vivo may depend to a large extent on the drug being used and on the individual cell type. Both types of defect in drug accumulation are of high importance when regimens include VCR a drug commonly used in second-line chemotherapy of B-CLL. Both defects in drug accumulation may be responsible for intrinsic VCR resistance in B-CLL.

Does IL-2 receptor expression and secretion in chronic B-cell leukemia have a role in down-regulation of the immune system?

Recent evidence of cell membrane expression of interleukin-2 receptors (IL-2R) by malignant B cells in hairy cell leukemia (HCL) and B-chronic lymphocytic leukemia (B-CLL) has lead to speculation that growth factors, such as IL-2, may play a role in the pathophysiology of these diseases. However, to date, it is not clear that IL-2 is a consistent growth factor in vitro or in vivo for malignant B cells. What then is the potential significance of membrane IL-2R on the malignant B-cell membrane? Laboratory analysis indicates that the malignant cells are the source of elevated serum levels of soluble Tac protein (sIL-2r alpha) in both diseases. Indeed, these cells spontaneously secrete sIL-2R alpha into culture medium. We speculate that the presence of an expanding mass of malignant B cells possessing high and low affinity membrane IL-2R may contribute significantly to the associated immunodeficiency seen in B-CLL. In particular, it is the cell associated high affinity IL-2R that have the greatest potential for reducing the levels of free IL-2 available to normal immune cells.

Cytokines and intracellular signals involved in the regulation of B-CLL proliferation

Cytokines play an important role in the regulation of both normal and malignant B cells. In this paper we give a brief overview of the major cytokines involved in the regulation of B-CLL proliferation. In vitro experiments have indicated that there is an antagonistic interaction between TNF-alpha as a growth-enhancing factor and IL-4, which inhibits the growth of B-CLL. We have extended these findings with recent experiments on the intracellular signals which might be involved in these processes. We show that increased levels of intracellular cAMP dose-dependently inhibit the TNF-alpha-induced proliferation of B-CLL. On the basis of these results, we propose a model for the signals involved in the regulation of B-CLL proliferation. The implications for possible new ways of treatment are discussed.

APO-1 mediated apoptosis or proliferation in human chronic B lymphocytic leukemia: correlation with bcl-2 oncogene expression

We studied induction of apoptosis in several human malignant B cells from chronic lymphocytic leukemias (BCLL) by triggering the APO-1 antigen. The APO-1 antigen was found to be expressed on the surface of malignant B cells. In BCLL cells from most patients, APO-1 antigen expression increased following in vitro activation by Staphylococcus aureus Cowan I (SAC) or interleukin-2 (IL-2). In certain cases of BCLL co-stimulation with SAC plus IL-2 resulted in a synergistic up-regulation of the APO-1 antigen on the cell surface and prepared BCLL cells for monoclonal antibody anti-APO-1 mediated apoptosis. Interestingly, bcl-2 mRNA expression decreased upon stimulation with SAC plus IL-2, whereas SAC or IL-2 alone did not affect the level of bcl-2 expression. Thus, in these BCLL cells induction of anti-APO-1-mediated apoptosis appeared to be correlated with bcl-2 mRNA down-regulation. One informative BCLL, however, with a similar pattern of APO-1-antigen expression, did not show SAC plus IL-2-dependent bcl-2 down-regulation. Surprisingly, these cells proliferated in response to anti-APO-1 only when cells were co-stimulated with SAC plus IL-2. Our data suggest that down-regulation of bcl-2 prepares BCLL cells for induction of APO-1-mediated apoptosis. In addition they demonstrate that triggering of the APO-1 antigen may also lead to the induction of proliferation in special cases of BCLL.

[Spontaneous remission in chronic lymphatic leukemia]

We describe three patients with chronic lymphocytic leukemia who had a complete spontaneous remission, and review the cases reported in the literature. The mechanism leading to spontaneous remission is unknown, but it is speculated that the loss of a leukemia inducing oncogene or the reappearance of a leukemia suppressor gene could be involved. The interesting observation that, in some reported patients, the remission followed a viral infection, raises the question whether a virus-induced defense mechanism plays a causal role.

Immune and hormonal changes in early-stage chronic lymphocytic leukemia patients

Fifty-six previously untreated stage-I (according to Rai) chronic lymphocytic leukemia (CLL) patients were examined for their clinical data, immunological characteristics, and hormonal values. Dysfunction of T and B lymphocytes was demonstrated by changed lymphocyte blastogenic response to stimulation with phytohemagglutinin (PHA), concanavalin A (ConA), pisum sativatum agglutinin (PSA), wheat germ agglutinin (WGA), recombinant interleukin 2 (IL 2), and dextran sulfate (DxS); also by decreased immunoglobulin levels (IgG, IgA, IgE) and increased beta 2-microglobulin (beta 2-M) values. Simultaneously, dysregulation of the hypothalamic-pituitary-adrenal axis, immune system integration, imbalance of sex hormones, and changes in thyroid hormones were observed in the same group of patients. Disturbed immunohormonal interactions in early-stage CLL may be responsible for the pathogenetic mechanisms in this lymphoproliferative malignancy.

A prospective study of the evolution of chronic lymphocytic leukaemia

The clinical course of chronic lymphocytic leukaemia (CLL) in 126 patients has been examined over the period 1961-88. The evolution of early stages, 0-I, to late stages, III-IV, occurred frequently without an orderly progression through the intermediate stages. The tumour load as judged by lymphadenopathy and splenomegaly was similar in stages II, III and IV. It would seem that stages 0-II represent a continuous spectrum of increasing tumour load, whereas stages III and IV with tumour load of equal magnitude and suppression of haemopoiesis are likely results of a change in biological behaviour of malignant lymphocytes. Stage II(S) characterised by splenomegaly and absence of lymphadenopathy seems a distinct entity with a unique clinical course. Further evolution of CLL in these patients was characterised by progressive splenomegaly, and as this became marked the clinical course was dominated by 'hypersplenism'. Splenectomy at this late stage led to rapid relief of symptoms, progressive increase of Hb and platelets to normal levels and to a quiescent phase of CLL for a considerable period. The tumour load in stage II(S) was of the same order of magnitude as in stages II, III and IV, yet the survival was similar to that in stage 0. Survival correlated with clinical stage and age at the time of diagnosis, but showed no relation to sex. The significance of these findings is further discussed.

Fibrinogen deposition and macrophage-associated fibrin formation in malignant and nonmalignant lymphoid tissue

Nonmalignant lymphoid tissue and tissue from patients with nodular sclerosis, Hodgkin's disease, and large cell lymphocytic lymphoma was examined by immunohistochemical techniques for the occurrence in situ of components of coagulation and fibrinolysis reaction pathways. Staining for material interpreted as fibrinogen was observed in abundance in both malignant and reactive lymphoid tissue. Fibrin also occurred to a variable extent but focally in all tissues. Components of coagulation pathways, including tissue factor, factor VII, factor X, and factor XIII ("a" subunit), were restricted to tissue macrophages. Double-labeling techniques revealed fibrin in direct apposition to tissue macrophages. We conclude that fibrinogen and fibrin occur in both benign and malignant lymphoid tissue and that the transformation of fibrinogen to fibrin is attributable to macrophage-initiated thrombin formation. We postulate that both systemic and local hypercoagulability associated with these disorders may be attributable to macrophage activation resulting in expression of procoagulant activity.

The NZB mouse as a model for chronic lymphocytic leukemia

Chronic lymphocytic leukemia (CLL) is the most common leukemia in the Western world and the only leukemia for which a possible genetic component has been described. Analysis of this genetic component has been hindered by the fact that disease onset normally occurs after age 50. We report here the aged NZB mouse as an animal model for CLL. NZB mice have a genetically regulated, age-dependent onset of clonal, aneuploid cells which are IgM+ and Ly1+ (CD5+ B-cells). Peripheral blood smears from old NZB mice show an increase in circulating lymphocytes and "smudged" or ruptured cells, often seen in human CLL. Electron microscopic examination of these cells shows them to be mature lymphocytes. Light microscopy of the spleen shows infiltration of small lymphocytes and is consistent with CLL pathology. These long-lived, CLL-like cells can be serially passaged into recipient animals. This continued passage occasionally results in the development of a large cell lymphoma detectable in the spleen, lymph nodes, and liver. The histology of this lymphoma is quite distinct from that of the CLL-like cells, but the phenotype is that of an aneuploid CD5+, IgM+ cells. This apparently represents a continued transformation of the CLL-like clone similar to the development of Richter's syndrome in human CLL. Therefore, the NZB mouse can be a valuable tool for the determination of the genetic basis of CLL ontogeny and the conversion of CLL into Richter's syndrome.

[Chronic lymphoid leukemia in the Ivory Coast. (69 cases)]

We report on sixty-nine cases of chronic lymphocytic leukaemia. This report describes the result over a period of eleven years. We have pointed out that chronic lymphocytic leukaemia is most frequent in adults. It occurs on adult (mean age fifty years) with a maximum between forty-one and fifty years old. It is in agreement with others series described elsewhere in Africa. We have noted a predominance in women. The splenomegalia is the predominant clinical sign as it was related also in Africa countries.

[Ultrasonographic characteristics of the liver in chronic and acute leukemia]

Parenchyma of the liver and blood flow in the portal system were studied in patients with acute and chronic leukemias. Ultrasonic investigations of the liver with the use of Doppler's method were conducted in 82 leukemia patients. It has been found that in most cases of leukemia not only the size but also ultrasonic characteristics of parenchyma of the liver are changed. The echo-structure of the liver depends, first of all, on the duration of the disease and chemotherapy conducted, and, to a lesser degree, on the clinico-morphological forms of leukemias. At the same time a rise is observed in the portal blood flow rate that may be compensatory in response to anemia. Pronounced dilatation of the splenic vein and of the main stem of the hepatic vein, as well as an increased minute blood volume in hepatic vein of chronic leukemia patients, are, probably, caused by increased venous outflow from the enlarged spleen.

The leukemic B-cell population of patients with monoclonal lymphocytosis of undetermined significance (MLUS) are functionally distinct from the chronic lymphocytic leukemia (CLL) derived cell population

Some patients with CLL survive for decades with a stable lymphocytosis without other signs of progression of the disease. This condition has been termed monoclonal lymphocytosis of undetermined significance (MLUS). The aim of the present study was to search for functional differences between the monoclonal B-cell population of CLL (n = 3) and MLUS (n = 5) patients. MLUS derived B-cell populations were susceptible to Epstein-Barr virus (EBV) infection measured as the production of EB nuclear antigen (EBNA) whereas CLL derived cells were resistant. In 4 out of 5 MLUS patients, lymphoblastoid cell line (LCL) like cell-clumps were formed, but not in CLL. The clonal B-cell population from 2 of 5 MLUS patients was immortalized by EBV (LCL restricted to the expression of one Ig light chain) while no cell line emerged from the CLL patients. Phorbol esters induced cell to cell adhesion of MLUS and normal B cells but not of CLL derived cells. This study further enlarges previous observations and strengthens the assumption that MLUS clonal B cells are functionally close to normal B cells while CLL B cells display various functional abnormalities.

Distinct characteristics of lymphokine-activated killer (LAK) cells derived from patients with B-cell chronic lymphocytic leukemia (B-CLL). A factor in B-CLL serum promotes natural killer cell-like LAK cell growth

We show that lymphokine-activated killer (LAK) cell precursors derived from patients with B-cell chronic lymphocytic leukemia (B-CLL) and cultured in the presence of recombinant interleukin-2 and normal human serum (NHS), develop into primarily NK cell-like (CD 57+) LAK cells, whereas identically prepared LAK cell precursors from normal subjects develop into mainly T cell-like (CD 3+, CD 8+) LAK cells. B-CLL LAK cells exhibited greater proliferative capacity than did normal LAK cells. When normal LAK cells were grown in B-CLL serum instead of NHS, their proliferation increased; NK cell levels also increased to those found in B-CLL LAK cells, suggesting that B-CLL serum contains a factor that promotes NK cell-like growth, LAK cells derived from normal or B-CLL patients demonstrated similar lytic activity toward K562 and Raji cells. Growth in B-CLL serum did not reduce their lytic potential. Thus, the altered phenotype and growth exhibited by B-CLL LAK cells and normal LAK cells grown in B-CLL serum does not lead to abnormalities in their cytolytic functions. We propose instead that the predominance of NK-like cells in B-CLL LAK cell populations and the presence of an NK cell-like growth factor in B-CLL serum reflect abnormalities related to NK cell-mediated B-cell regulation; ie, either inhibition of normal B-cell growth and/or growth stimulation of the leukemic clone in B-CLL.

Lymphokine-activated killer (LAK) cell activity in B and T chronic lymphoid leukemia: defective LAK generation and reduced susceptibility of the leukemic cells to allogeneic and autologous LAK effectors

The capacity to generate lymphokine-activated killer (LAK) cells and the susceptibility of the neoplastic cells to both allogeneic and autologous LAK effectors were studied in B and T chronic lymphoproliferative disorders. While in B-cell chronic lymphocytic leukemia (B-CLL) the depressed natural killer function could be restored after a 7-day incubation with recombinant interleukin (IL-2), B-CLL mononuclear cells showed a reduced LAK activity compared with normal LAK cells. Furthermore, in all but 1 of the 20 B-CLL samples tested the leukemic cells were totally resistant to autologous LAK effectors. In most cases the leukemic cells were also resistant to normal allogeneic LAK cells. Competition experiments demonstrated that the patients' LAK cells, as well as normal LAK effectors, were capable of recognizing B-CLL cells, pointing, therefore, to a postbinding cytolytic defect. In hairy cell leukemia (HCL) an overall reduced LAK activity against allogeneic targets was documented, but, at variance from B-CLL, hairy cells were often susceptible to the lytic effect of normal LAK cells, and in half of the cases tested the neoplastic population was also sensitive in an autologous system. Similarly to B-CLL, in the great majority of T chronic lymphoproliferative disorders studied, the pathologic cells were resistant to normal and autologous LAK effectors and a defective LAK generation was found. These results demonstrate that in most B and T chronic leukemias the LAK function is defective and, when inducible, does not appear directed against the leukemic population. The possibility of exploiting an immunotherapeutic approach with IL-2/LAK cells in the management of chronic lymphoproliferative disorders does not gain support by these findings.

B cell small lymphocytic lymphoma and chronic lymphocytic leukemia with peripheral neuropathy: two cases with neuropathological findings and lymphocyte marker analysis

Two patients with lymphoproliferative disorders developed peripheral neuropathy and neoplastic lymphocytic nerve infiltrates. One of these patients, with B cell small lymphocytic lymphoma, presented with a chronic axonal neuropathy. CD22+, CD5- cells were identified in the epineurium. The other patient with chronic lymphocytic leukemia of 3 years duration developed a mixed axonal and demyelinating neuropathy. CD22+ and CD5+ cells were observed in the endoneurium. While the cause of the neuropathy in these two cases is unknown, intraneural or systemic autoantibody production may have led to the development of disease.

A randomized clinical trial of chlorambucil versus COP in stage B chronic lymphocytic leukemia. The French Cooperative Group on Chronic Lymphocytic Leukemia

In 1980, the French Cooperative Group on Chronic Lymphocytic Leukemia started a randomized clinical trial in which intermediate prognosis patients (stage B) received either an indefinite course of chlorambucil (0.1 mg/kg/d) or 12 cycles of the COP regimen (vincristine, cyclophosphamide, and prednisone). We present the results of the third interim analysis based on 291 patients (151 in the chlorambucil group and 140 in the COP group) with a mean follow-up of 53 months at the reference date of June 1, 1987. At this date, 129 deaths were observed, 65 in the chlorambucil group and 64 in the COP group; there was no improvement in overall survival with the COP regimen (P = .44) even after adjusting for both prognostic and imbalanced factors (P = .24). The 3-year and 5-year overall survival rates were, respectively, 69% and 44% in the chlorambucil group as compared with 73% and 43% in the COP group. The median survival times were 58 months in the chlorambucil group and 57 months in the COP group. Moreover, no significant difference was observed between the two treatment groups in terms of either treatment response, 9-month status, time to disease progression to stage C, or causes of death.

Effects of chlorambucil and therapeutic decision in initial forms of chronic lymphocytic leukemia (stage A): results of a randomized clinical trial on 612 patients. The French Cooperative Group on Chronic Lymphocytic Leukemia

In 1980, the French Cooperative Group on Chronic Lymphocytic Leukemia started a randomized clinical trial in which 612 good prognosis patients (stage A) received either no treatment (309 patients) or an indefinite course of chlorambucil at the daily dose of 0.1 mg/kg (303 patients). Overall survival appeared to be better in the untreated group (50 deceased patients compared with 62 in the chlorambucil group), but the difference was not significant (P = .21) even after adjusting for both prognostic and imbalanced factors (P = .09). The crude 5-year survival rates were 82% in the untreated group and 75% in the chlorambucil group. The action of chlorambucil appeared to be a complex phenomenon associating beneficial effects consisting in slowing down disease progression to stage B or C (P less than .01), and favoring disease remission with harmful effects given by a short survival after disease progression to stage B or C in the chlorambucil group and an increased incidence of epithelial cancers (33 v 19), as well as an excess of epithelial cancer deaths (13 v 3), in the chlorambucil group. As these results suggested an overall harmful effect of chlorambucil, we tried to define, within stage A patients, a group of patients with a low probability of disease progression. We showed that stage A patients with hemoglobin greater than or equal to 120 g/L and lymphocyte count less than 30 x 10(9)/L had a survival that was not significantly different (P = .46) from that of the age- and sex-matched French population. These patients, accounting for about 50% of all chronic lymphocytic leukemia patients, should not be treated unless disease progression is observed.

Experimental treatment of chronic lymphocytic leukemia with extracorporeal photochemotherapy. Initial observations

Based on the encouraging results obtained with extracorporeal photochemotherapy (EP) in the treatment of the exfoliative erythrodermic form of cutaneous T-cell lymphoma (CTCL), leukemic form, as well as other T-cell-mediated diseases we evaluated the therapeutic potential of EP in patients with chronic lymphocytic leukemia (B-CLL). Three patients with B-CLL were treated for a period of 1 year. Two patients showed stabilization of disease, as demonstrated by reduction in their peripheral white blood cell count, with one patient showing lymph-node resolution. A third patient with significant intolerance to previous chemotherapy did not respond within the observed period. No significant side effects of EP were observed. Our observations suggest that EP may have a positive effect on the course of B-CLL in selected patients. Additional clinical trials are warranted to further define the role of EP alone or in combination therapy in the management of B-CLL.

Resolution of a severe sensorimotor neuropathy following resection of an associated asymptomatic gastric lymphoma

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[Acute T-cell lymphoproliferative syndromes. A study of 29 cases]

The clinical and hematological profile, the response to therapy and the clinical evolution of 29 patients with acute T lymphoproliferative syndromes (ATLS) diagnosed during the last 5 years were evaluated. Mean age was 22.6 (SD 9.5) years. 24 patients were males and 5 females. Lymphadenopathy was present in 25 patients, hepatomegaly in 16 and splenomegaly in 14. Seventeen patients had a mediastinal mass. Anemia was present in 41% of patients and thrombocytopenia in 50%. The mean leukocyte count was 71 x 10(9)/l (SD 93). Bone marrow infiltration was found in 25 patients. The acid phosphatase reaction was positive, centrosomal type, in all cases except two. The immunophenotypic study classified the ATLS patients in the subtypes pre-T (10 cases), cortical thymic (15 cases), and mature thymic (4 patients). The cases with pre-T phenotype had a greater degree of bone marrow infiltration and lower frequency of mediastinal mass than the rest of patients. The rate of complete remissions (CR) was 83%. At the time of closing the study 12 patients had relapsed, with a median time of CR of 9.4 months. In addition, 11 patients had died, with a median survival of the series of 19 months. The results of the present study indicate that, despite some heterogeneity, those cases of ATLS with a more immature immunological phenotype (pre-T) have clinical and biological features more akin to acute leukemia, unlike those with a thymic phenotype (cortical or mature), which would be closer to lymphoblastic lymphoma.(ABSTRACT TRUNCATED AT 250 WORDS)

Transcriptional regulation of immunoglobulin expression in a chronic lymphocytic leukemia cell line

A cell line derived from a B-type chronic lymphocytic leukemia, Corinna II, was found to down-regulate its steady-state level of IgM mRNA after treatment with phorbol 12-myristate 13-acetate while the proliferative capacity of the cell line was unaffected. No changes in the splicing pattern of the IgM transcript could be observed after treatment. The down-regulatory effect on IgM RNA expression was found to be inhibited by cycloheximide, suggesting that functional protein synthesis was needed for the effect. Transfection experiments showed that the down-regulatory effect of phorbol myristate acetate was exerted at the level of transcriptional initiation. The DNA element mediating the down-regulatory effect was found to be present within 140 bp 5' of the mRNA cap site in an immunoglobulin promoter.

Differences in activities of murine retroviral long terminal repeats in cytotoxic T lymphocytes and T-lymphoma cells

Transcriptional activities of the long terminal repeats (LTRs) of various murine leukemia viruses were tested in the cytotoxic T-cell lines CTLL-1 and CTLL-2. In contrast to T-lymphoma cells, in which the LTRs of T-lymphomagenic virus SL3-3 and Moloney murine leukemia virus are more active than those of other viruses, transcriptional activity in these mature, interleukin-2-dependent cells is not correlated with the specificity of viral leukemogenicity. Several approaches were used to investigate the molecular basis for LTR activity differences in lymphoma cells and mature cytotoxic T cells. Deletion analysis of the Moloney virus LTR showed that the direct repeats associated with enhancer activity have, at most, a slight effect on expression in CTLL-1 cells, whereas they stimulate expression six- to eightfold in T-lymphoma cells. This suggests that the mature T-cell line lacks one or more factors present in T-lymphoma cells that function to augment transcription from the Moloney murine leukemia virus LTR. We also used recombinant viral LTRs to investigate the role of the enhancer core element of SL3-3 in CTLL-1 and CTLL-2 cells. A one-base-pair difference between the core sequences of SL3-3 and nonleukemogenic Akv virus, which is important for SL3-3 activity in T-lymphoma cells, had no effect in these cells. The inability to distinguish the single-base-pair difference in expression assays was correlated with the absence of binding of a cellular factor, S-CBF, to the SL3-3 enhancer core in extracts of CTLL-1 and CTLL-2 nuclei. These studies may have implications for identification of the target cells for viral leukemogenesis, as well as for tracing of changes in the transcriptional machinery during T-lymphocyte differentiation.