Stage B-cell Chronic Lymphocytic Leukemia Research Articles

Association between B-cell receptor responsiveness and disease progression in B-cell chronic lymphocytic leukemia: results from single cell network profiling studies

While many prognostic markers in B-cell chronic lymphocytic leukemia provide insight into the biology of the disease, few have been demonstrated to be useful in the daily management of patients. B-cell receptor signaling is a driving event in the progression of B-cell chronic lymphocytic leukemia and markers of B-cell receptor responsiveness have been shown to be of prognostic value. Single cell network profiling, a multiparametric flow cytometry-based assay, allows functional signaling analysis at the level of the single cell. B-cell receptor signaling proteins (i.e. p-SYK, p-NF-κB p65, p-ERK, p-p38, p-JNK) were functionally characterized by single cell network profiling in samples from patients with B-cell chronic lymphocytic leukemia in an exploratory study (n=27) after stimulation with anti-IgM. Significant associations of single cell network profiling data with clinical outcome (i.e. time to first treatment), as assessed by Cox regression models, were then confirmed in patients' samples in two other sequential independent studies, i.e. test study 1 (n=30), and test study 2 (n=37). In the exploratory study, higher responsiveness of the B-cell receptor signaling proteins to anti-IgM was associated with poor clinical outcomes. Patients' clustering based on signaling response was at least as powerful in discriminating different disease courses as traditional prognostic markers. In an unselected subgroup of patients with Binet stage A disease (n=21), increased anti-IgM-modulated p-ERK signaling was shown to be a significant, independent predictor of shorter time to first treatment. This result was independently confirmed in two test cohorts from distinct populations of patients. In conclusion, these findings support the utility of the single cell network profiling assay in elucidating signaling perturbations with the potential for the development of a clinically useful prognostic test in patients with early stage B-cell chronic lymphocytic leukemia. These data support the clinical relevance of B-cell receptor signaling in B-cell chronic lymphocytic leukemia, and suggest a key role of ERK activation in the physiopathology of this leukemia.

Prospective study of clinical and biological prognostic factors at diagnosis in patients with early stage B-cell chronic lymphocytic leukemia

Retrospective series have reported many clinical and biological significant prognostic factors in chronic lymphocytic leukemia (CLL). We describe a prospective cohort of 135 patients with CLL homogeneously studied at diagnosis for prognostic factors. Biological variables analyzed were CD38 and ZAP-70 expression, fluorescence in situ hybridization (FISH) for 13q−, +12, 11q−, and 17p−, and conventional cytogenetics. Univariate and multivariate analysis for progression-free survival (PFS) were performed in patients with early stage (Rai 0–1) CLL. CD38 was positive in 42 (31.6%) patients and ZAP-70 in 47 (35.9%). The most frequent FISH finding was isolated 13q− in 50 (38.5%) patients, and 17p− was found in 11 (8.4%). Among 135 patients, 114 (84.4%) were Rai 0–1 at diagnosis and 39 (28.9%) presented adenopathies. With a median follow-up of 39 months, the presence of lymphadenopathy in patients with Rai 0–1 stage CLL was the only significant variable for predicting PFS in multivariate analysis (odds ratio [OR] 7, 95% confidence interval [CI] 2.2–22, p = 0.001). When only biological factors were analyzed, CD38 expression (OR 3.2, 95% CI 1.1–9.3, p = 0.03) and 17p− (OR 3.5, 95% CI 0.95–13.1, p = 0.05) correlated with worse PFS. A longer follow-up is necessary to analyze the prognostic value of these variables regarding overall survival.

First-In-Human Phase I Dose Escalation Study of a Humanized Anti-CD200 Antibody (Samalizumab) In Patients with Advanced Stage B Cell Chronic Lymphocytic Leukemia (B-CLL) or Multiple Myeloma (MM)

AbstractAbstract 2465 Background:The immunosuppressive molecule CD200 is upregulated on B-CLL and MM cells which may contribute to tumor immune evasion. Samalizumab is a novel first-in-class recombinant humanized monoclonal antibody that specifically binds CD200 and blocks CD200-CD200R interactions. Preclinical data suggest that CD200 blockade may inhibit CD200-dependent immune suppression, enabling a more efficient immune response against CD200+ tumor cells. A first-in-human phase I/II trial was initiated to evaluate safety, maximum tolerated dose, pharmacokinetics (PK) and pharmacodynamic (PD) activity of samalizumab. Methods:In this 3+3 design, dose-escalation trial, pts with advanced stage B-CLL or MM (with or without prior therapy) received a single IV dose of samalizumab. Pts could receive additional 28-day cycles (1 dose/cycle) if first dose was tolerated and pts exhibited at least stable disease (SD). Assessments performed throughout cycle 1 and then every 2 wks included standard safety measures, HAHA, PK, PD, CBC, and CT scans (at cycle 4 and every other cycle thereafter). Results:Results are reported as of 20-Jun-10. Enrollment is complete with 26 pts (18M; median age 67 yrs, range 41–87) including 3 MM pts (2 at 500 mg/m2, 1 at 600 mg/m2) and 1 pt with SLL (500 mg/m2). Four pts had no prior chemotherapy; the other 22 had received a median of 2 regimens (range 1–9). Twenty pts (1 MM) received multiple (2–14+) cycles of samalizumab (86+ cycles in total); safety and efficacy data are available for 25 pts through the 500 mg/m2 cohort. Adverse events were mostly mild or moderate and manageable; the most common events were fatigue (48%), fever (20%) and rash (20%). Grade 3–5 events included neutropenia (12%) and infections (12%); no events were indicative of a cytokine storm. One non-drug-, non-CLL-related death occurred. Three pts developed HAHA. Although preliminary PK analyses (Table 1) indicate high variability due to the limited number of pts and differences in tumor burden, the median AUC of serum drug levels after the first dose (300–500 mg/m2) are consistent with a linear relationship between dose and AUC. AUC in the low dose cohorts (50–200 mg/m2) is unreliable as most PK values were below the level of quantification. PD effects consistent with inhibition of CD200-dependent immune suppression by samalizumab were observed. Out of 21 pts with sufficient peripheral immune cells to evaluate, 18 (86%) showed 81–98% reductions in peripheral CD200+CD4+ T cells and 14 (67%) demonstrated 64–75% CD200 loss on B-CLL cells following the first dose. These responses were transient at lower doses (50–200 mg/m2) and sustained at higher doses (300–500 mg/m2), indicating a dose-dependent immunoregulatory effect. Eight of 21 evaluable pts (38%) showed an increase in CD200R+ CD4+ T cells. Regulatory T cell (Treg) levels decreased 20–57% (median = 38%) in 4/7 (57%) pts whose clinical disease stabilized or improved, whereas only 5/17 (29%) pts whose disease progressed clinically showed a similar decrease (13–62%; median = 18%). Modest first-dose Th1 cytokine responses were noted in 10/25 pts. Two pts who received ≥ 9 cycles showed reduction in tumor burden by CT scan (including 1 pt with a 58% reduction and near normalization of absolute lymphocyte cell count), associated with a reduction in Tregs and increase in activated T cells over time. No MTD was identified. Conclusion:Samalizumab appears to be well tolerated and exhibits a dose-dependent linear increase in serum AUC, dose-dependent changes in CD200+ B-CLL and CD4+ T cells, and modest Th1 cytokine responses. These PD effects are consistent with the predicted immunomodulatory mechanism of action. Anti-tumor activity is evident in some pts receiving multiple cycles. Treatment is ongoing with plans for additional studies of samalizumab to explore other dosing regimens.Table 1:Dosing, Safety, PK & PD Parameters by CohortSamalizumab Dose (mg/m2)No. pts (n = 25)PKEnrolledDosed ≥4 cyclesAE grade ≥3HAHA1st-dose Th1 CytokinesSystemic Clearance L/h median (range)Distributional Clearance L/h median (range)AUC mg h/mL median (range)50413120.01 (0.006–0.27)0.03 (0.0008–2.5)–100552000.04 (0.005–0.11)0.002 (0.001–0.003)–200310220.03 (0.007–0.06)0.02 (0.002–6.13)–300322010.01 (0.01–0.01)0.05 (0.02–0.6)28.13 (19–36)400321000.02 (0.01–0.02)0.13 (0.12–22.2)35.64 (30–38)500701050.02 (0.01–0.04)0.04 (0.02–0.41)45.09 (25–74) Disclosures:Mahadevan: Alexion Pharmaceuticals, Inc: Honoraria, Speakers Bureau. Whelden: Alexion Pharmaceuticals, Inc: Employment, Equity Ownership. Faas: Alexion Pharmaceuticals, Inc: Employment, Equity Ownership. Ulery: Alexion Pharmaceuticals, Inc: Employment, Equity Ownership. Kukreja: Alexion Pharmaceuticals, Inc: Employment, Equity Ownership. Li: Alexion Pharmaceuticals, Inc: Employment, Equity Ownership. Bedrosian: Alexion Pharmaceuticals, Inc: Employment, Equity Ownership. Heffner: Alexion Pharmaceuticals, Inc: Research Funding.

High intracellular content of cyclin‐dependent kinase inhibitor p27Kip1 in early‐ and intermediate stage B‐cell chronic lymphocytic leukemia lymphocytes predicts rapid progression of the disease

Previous studies showed that peripheral blood lymphocytes of B-cell chronic lymphocytic leukemia (B-CLL) displayed a high intracellular level of cell cycle inhibitory protein p27(Kip1). It has been suggested that its' high expression may confer them survival advantage and lead to unfavorable prognosis, but the prognostic significance of p27(Kip1) expression for previously untreated, non-advanced stage B-CLL was not established. We studied a relationship between the intracellular level of p27(Kip1) of lymphocytes of early- and intermediate stage B-CLL patients and their spontaneous apoptosis in vitro, as well as prognostic significance of p27(Kip1) in B-CLL lymphocytes for the risk of disease progression. Intracellular p27(Kip1) content of peripheral blood lymphocytes obtained from 48 previously untreated 0-II Rai stage B-CLL patients was determined by flow cytometry. The viability and apoptosis of those lymphocytes after 72-h culture were also assessed. During the follow-up period (6-71 months, median 59.5), we recorded the time elapsed to the doubling of lymphocyte count, progression to a higher Rai stage and the appearance of indications for cytostatic treatment. The p27(Kip1) expression was neither correlated with initial lymphocyte count, CD38 expression, cell viability nor spontaneous apoptosis ratio after 72-h culture. Higher p27(Kip1) level was related to the probability of earlier occurrence of each of three above-mentioned events. We did not find a prognostic significance of in vitro cell viability nor apoptosis as to the risk of disease progression. Our results indicate that elevated intracellular p27(Kip1) level in leukemic lymphocytes of early- and intermediate stage B-CLL patients contributes to rapid progression of the disease.

Menstruation protects women from B-cell chronic lymphocytic leukemia

B-cell chronic lymphocytic leukemia (B-CLL) affects women and men with different frequency: men show a more than double as high risk to acquire this disease than women. The reason for this sex-related difference is unknown. It is proposed here that menstruation confers advantages to women in two ways: i) early stage B-CLL cells and/or their potential precursors are partially removed from the body with menstrual bleeding which includes shedding of endometrial tissue; and ii) during degradation of the remaining endometrial tissue an immune response against B-CLL is triggered. The regular reduction of potential B-CLL cells throughout pre-menopausal life as well as the immunization against B-CLL would enable the female organism to better control outbreak and course of the disease. Both processes depend on specific binding of the leukemic cells to the endometrial tissue. CD23 expressed on the surface of B-CLL cells is suggested to mediate binding to the vitronectin receptor/CD47 expressed on endometrium. The menstrual inflammatory process includes danger signals that might facilitate initiation of an anti-leukemia immune response. Menstrual immunization might explain sex-related differences in clinical features of other malignancies as well and might therefore have broad implications for the development of individualized therapies.

RHAMM/CD168 Is a Novel Leukemia Associated Antigen with Prognostic Value for Patients with B-Cell Chronic Lymphocytic Leukemia.

Background and Aims: Differential expression of molecules in patients with B-cell chronic lymphocytic leukemia (B-CLL) might define suitable targets for T cell based vaccines and/or antibody approaches.Methods: We assessed the mRNA expression of the tumor associated antigen (TAA) RHAMM/CD168 defined earlier by serological analysis of cDNA expression libraries (SEREX) from leukemic cells.Results: Peripheral blood mononuclear cells from 40 B-CLL patients and 20 healthy volunteers (HVs) were examined by quantitative RT-PCR. A leukemia-restricted expression of the antigen RHAMM/CD168 was observed in 39/40 B-CLL patients in contrast to the absence of its expression in HVs. To evaluate the immunogenicity of this novel LAA, mixed lymphocyte peptide cultures (MLPCs), followed by enzyme-linked immunosorbent spot (ELISPOT) and flow cytometry assays were performed to detect antigen-specific CD8+ T cells. RHAMM/CD168 specific responses by CD8+ HLA-A2/R3tetramer+CCR7-CD45RAhigh effector T cells were detected. As these CD8+ T cells contribute to the elimination of RHAMM+ CLL cells, we questioned whether expression of the antigen would be associated with a better survival. RHAMM/CD168 expression revealed to be higher in patients with unmutated IgVH status. RHAMM normalized against the housekeeping gene TATA binding protein (TBP), i.e. the RHAMM/TBP ratio was defined as a prognostic surrogate marker for B-CLL. B-CLL patients with a RHAMM/TBP ratio > 1.67 showed a significantly shorter treatment free survival (TFS) (Fig. 1). A tendency towards higher RHAMM/TBP expression ratios was observed in B-CLL cases with del11q.Conclusion: RHAMM/CD168 is a novel LAA in B-CLL patients, an antigen correlating with the clinical course of the disease. Therefore, we consider RHAMM/CD168 an interesting target for immunotherapy in early stage B-CLL patients, especially with worse prognosis (IgVH unmutated). [Display omitted]

Composite mycosis fungoides and B-cell chronic lymphocytic leukemia

Concordant or composite mycosis fungoides and B-cell chronic lymphocytic leukemia (B-CLL) is exceedingly rare, with only 10 cases previously described to our knowledge. We report a case of a 64-year-old woman who developed generalized erythroderma 5 years after the diagnosis of early stage B-CLL. Over the next 6 years of her clinical course multiple sequential samples of skin, peripheral blood, and one enlarged lymph node were studied in detail by flow cytometry, immunohistochemistry, molecular diagnostics, and electron microscopy. The progressive cutaneous infiltrates were initially characterized as leukemia cutis, infiltration by B-CLL. Three years later, when she developed worsening skin disease and lymphadenopathy, the cutaneous infiltrates were characterized as cutaneous T-cell lymphoma. At that point, a biopsy of an enlarged lymph node revealed a composite lymphoma of both B-CLL and cutaneous T-cell lymphoma, and the peripheral blood also contained circulating cells of both neoplasms. Herein we summarize the literature on concordant cutaneous T-cell lymphoma and B-CLL, and the literature on concordant T- and B-cell neoplasms in general, with a review of the postulated relationships between these neoplasms.

Chronic lymphocytic leukemia.

This update of early stage B-cell chronic lymphocytic leukemia (B-CLL) embraces current information on the diagnosis, biology, and intervention required to more fully develop algorithms for management of this disease. Emphasis on early stage is based on the rapid advancement in our understanding of the disease parameters and our increasing ability to predict for a given early stage patient whether there is a need for more aggressive management. In Section I, Dr. Terry Hamblin addresses the nature of the disease, accurate diagnostic procedures, evidence for an early "preclinical" phase, the use of newer prognostic features to distinguish who will be likely to progress or not, and whether it is best to watch or treat early stage disease. In Section II, Dr. Neil Kay and colleagues address the biologic aspects of the disease and how they may relate to disease progression. Review of the newer insights into gene expression, recurring genetic defects, role of cytokines/autocrine pathways, and the interaction of the CLL B cell with the microenvironment are emphasized. The relationship of these events to both trigger disease progression and as opportunities for future therapeutic intervention even in early stage disease is also considered. In Section III, Dr. John Byrd and colleagues review the historical and now current approaches to management of the previously untreated progressive B-CLL patient. They discuss what decision tree could be used in the initial decision to treat a given patient. The use of single agents versus newer combination approaches such as chemoimmunotherapy are discussed here. In addition, the place of marrow transplant and some of the newer antibodies available for treatment of B-CLL are considered. Finally, a challenge to utilize our growing knowledge of the biology of B-CLL in the early stage B-CLL is proffered.

Serum Levels of Soluble CD23, but not Soluble CD25, Predict Disease Progression in Early Stage B-Cell Chronic Lymphocytic Leukemia

Serum levels of the soluble forms of CD23 (sCD23) and CD25 (sCD25) were prospectively analyzed with respect to their prognostic relevance in early stage B-cell chronic lymphocytic leukemia (B-CLL). SCD23 and sCD25 levels were determined in 105 patients with newly diagnosed B-CLL (Binet stage A). In 93 of the patients, these levels were correlated with other already established indicators for risk of disease progression, including the histologic pattern of bone marrow infiltration, lymphocyte doubling time (LDT), and the serum level of thymidine kinase (TK). High serum levels of both sCD23 and of sCD25 were associated with a diffuse bone marrow infiltration, a LDT ≤12 months, and elevated (>5 U/L) serum TK, respectively. Moreover, examination of the clinical course of 76 untreated patients showed that high levels of sCD23, but not of sCD25, at initial diagnosis were linked with disease progression. Furthermore, in a stepwise Cox regression model, high levels of sCD23 and a short LDT were shown to be strong predictors of progressive disease within the first year of disease presentation. Therefore, it appears to be justified to incorporate sCD23 levels into the risk profile of early stage B-CLL and to take them into account for stratification in risk-adapted treatment strategies.