ALBERT

Description: High-dose therapy plus autologous stem cell transplant (ASCT) is the standard of care for patients with multiple myeloma (MM) aged ≤65 years. Melphalan–prednisone (MP)-based therapy is the standard for non-ASCT candidates but is not typically used for transplant-eligible patients as prolonged therapy with melphalan can adversely affect stem cell collection. The phase 3 VISTA study demonstrated the superior efficacy of bortezomib plus MP (VMP) versus MP in previously untreated MM patients ineligible for ASCT. In this phase 2 study, we evaluated the efficacy of a shorter course of VMP on a different treatment schedule as induction therapy prior to ASCT or as frontline therapy in non- ASCT candidates. Patients aged ≥18 years with previously untreated MM received up to six 28-day cycles of bortezomib 1.3 mg/m2 IV, days 1, 4, 8, and 11, plus oral melphalan 6 mg/m2 and oral prednisone 60 mg/m2, days 1–7. After 2–6 cycles, ASCT-eligible patients could proceed to stem cell mobilization (G-CSF 10 mg/kg/day ± GM-CSF 250 mg/m2/ day or cyclophosphamide 4 g/m2 + GM-CSF) and conditioning with melphalan 200 mg/ m2 (140 mg/m2 if aged 〉65 years). Response was assessed every two cycles and post- ASCT by International Uniform Response Criteria. The primary end point was complete response (CR) rate to VMP. A total of 45 patients were enrolled; 27 were male. Median age was 63 years (range 33–75). MM subtype was 67% IgG, 16% IgA, and 9% each κ- and λ- light-chain; 37% of patients had ISS Stage III MM, 22% had ECOG performance status 〉1, and 70% had ≥40% plasma cells in bone marrow. In total, 20 patients proceeded to ASCT. Median duration of VMP was 4 cycles in both non-ASCT (range 1–6) and ASCT (range 2–6) patients. Response rate (best response) to VMP was 95% (42 of 44 evaluable patients), including 9% stringent CR (sCR), 9% CR (18% ≥CR [95% CI: 7%, 30%]), 27% very good partial response (VGPR), and 50% partial response (PR). Best response was achieved after cycle 2 in 10 patients, cycle 4 in 25 patients, and cycle 6 in 7 patients. All 20 ASCT patients had successful stem cell mobilization; median yield of CD34+ cells/ kg was 5.6 x 106 (range 2.3–12.2 x 106), in a median of 2 collection days. Post-transplant responses were 10% sCR, 20% CR, 55% VGPR, and 5% PR; the remaining 2 patients need further follow-up for response assessment. Response improved post-VMP to post-ASCT in 10 patients (6 PR to VGPR, 2 PR to CR, 2 VGPR to CR). After median follow-up of 14.0 months (range 7.4–47.7) and 14.6 months (range 8.2–42.9) in non-ASCT and ASCT patients, respectively, both median time to progression and progression-free survival were 19.8 months (95% CI: 14.3 months, not estimable [NE]) in non-ASCT patients and 27.9 months (95% CI: 14.6 months, NE) in ASCT patients. A total of 7 patients (5 non- ASCT, 2 ASCT) have died; 1-year survival rate was 82% (95% CI: 59%, 93%) in non- ASCT patients and 95% (95% CI: 69%, 99%) in ASCT patients. Most common grade 3/4 adverse events in all 45 patients during VMP therapy included peripheral neuropathy (24%), thrombocytopenia (20%), neutropenia (18%), and infection (9%). Only 1 patient had deep-vein thrombosis. In conclusion, VMP represents a highly effective therapy for previously untreated MM, with 45% of patients achieving VGPR or better, including 18% sCR/CR. Toxicities were predictable and generally manageable. Short-course VMP therapy did not negatively impact stem cell mobilization, supporting its use as induction therapy prior to ASCT. Very high post-transplant response rates were seen, with 85% of patients achieving ≥VGPR, including 30% sCR/CR. Since achievement of CR/VGPR is associated with improved long-term outcomes in MM, the preliminary outcome data presented here appear promising; however, longer follow-up is required.

Description: Survival of CLL cells requires sustained activation of the anti-apoptotic PI-3-kinase/Akt pathway, and many therapies for CLL cause leukemia cell death by triggering apoptosis. Blood lipoprotein particles are either pro- or anti-apoptotic. High density lipoprotein (HDL) particles are anti-apoptotic through sphingosine-1-phosphate receptor 3 (S1P3)-mediated activation of the PI-3-K/Akt pathway. We have noted that apoE4-very low density lipoprotein (VLDL) (but not apoE2- or apoE3-VLDL) particles increase apoptosis of endothelial cells by recruiting the phosphoinositol phosphatase SHIP-2 to the plasma membrane, thereby directly inhibiting the anti-apoptotic activity of HDL (DeKroon R, et al., Circ Res99:829–836, 2006). Since apoE4-VLDL increases apoptosis of certain cells, and since increased leukemia cell apoptosis favors longer survival in CLL, we hypothesized that APOE4 genotype would beneficially influence the clinical course of CLL. Of the 193 CLL patients (50 women and 133 men) studied, 29% had an APOE4 genotype. In the entire group, survival of men and women was not statistically different. However, women (but not men) with an APOE4 genotype had markedly longer survival than non-APOE4 patients (median 〉25 yr vs. 14.0 yr; p = 0.02) (Figure). Figure Figure Men and women had the same time-to-treatment (treatment-free survival) irrespective of APOE genotype. VLDL is metabolized to LDL by the actions of LPL. Patients had shorter survival and time-to-treatment if their CLL cell lipoprotein lipase (LPL) mRNA levels were high (p = 0.002). In analyzing APOE genotype and LPL levels in the same patients, we demonstrated that APOE4 was a more important determinant of survival than was the LPL level (p = 0.0007). The beneficial effect of APOE4 in CLL survival is likely mediated through allele-specific influences of APOE4 on serum lipoproteins increasing leukemia cell apoptosis. The frequency of the APOE alleles in the CLL patient population was not significantly different than that of a control population (16 and 13%, respectively). APOE genotype therefore does not appear to affect susceptibility to CLL, but influences the clinical course of disease, particularly after therapy is initiated. In contrast, APOE genotype does influence susceptibility to other diseases, most notably Alzheimer’s disease in which APOE4 markedly increases risk. The beneficial impact of APOE4 in CLL and its deleterious impact on Alzheimer’s disease expression may relate to a common mechanism of APOE4 in enhancing apoptotic cell death. APOE genotyping of patients with CLL may provide important clinical prognostic information, particularly in women. Most importantly, the allele-specific influence of APOE on disease progression may provide important new insights into the mechanisms of disease and response to therapy, and lead to new agents for treatment.

Description: Background and Significance : Chronic lymphocytic leukemia (CLL) is the most heritable hematologic malignancy; however, no common CLL predisposition genes are known. Monoclonal B lymphocytosis (MBL) is a hematologic syndrome characterized by small accumulations of B lymphocytes in the peripheral blood. MBL has a CLL-like immunophenotype, may progress to overt CLL, and is over represented in CLL families. Therefore, MBL observed in the context of familial CLL may be a marker of inherited risk for development of CLL. Detailed characterization of family-associated MBL may also provide mechanistic insights into the pathogenesis of familial CLL. Our strategy was to detail the biologic characteristics of CLL in family-associated MBL. Methods : Persons with MBL were identified by flow cytometric screening of peripheral blood from unaffected members of CLL kindreds ascertained by Genetic Epidemiology of CLL Consortium (GEC) sites. Flow cytometry was used to determine the surface immunophenotype including CD38 and intracellular ZAP-70. We defined MBL as populations of CD19+, CD5+, CD20lo, CD23+ B cells that comprised at least 2% of the CD19+ peripheral B cell compartment and did not exceed 5.0 × 109 MBL cells/L. RNA and genomic DNA from single MBL cells isolated by flow cytometric sorting were analyzed using PCR to determine immunoglobulin heavy and light chain sequences. MBL cells were sorted in bulk for FISH for loci associated with clinical CLL. Results : Twenty-two out of 190 (12%) unaffected family members were found to have MBL. We observed significant variability in the size of the MBL clone as a percentage of the CD19+ B cell compartment (mean 32%; range 2%–97%). Nonetheless, the absolute size of the MBL clone was small, 15 of 17 individuals had 〈 200 × 106 MBL cells/L. CD38 expression (defined as CD38 surface expression in ≥30% of MBL cells) was observed in 8 of 18 subjects tested. ZAP-70 (defined as intracellular expression in ≥ 20% of MBL cells) was expressed in 4 of 12 participants. Among 12 subjects tested, 5 MBL expressed both surface IgD and IgM, 3 expressed IgD only, 2 expressed IgM only, and 2 did not express IgD or IgM. Analysis of immunoglobulin heavy and light chains has been completed in 8 individuals. Both immunoglobulin heavy chain variable (IgVH) region mutated (n = 12) and unmutated (n = 4) sequences were observed. Four of 8 individuals had 2 or more unrelated MBL clones (range 2–5), including one individual with both unmutated and mutated clones. Among the 16 MBL clones identified in these 8 subjects, VH3 or VH4 rearrangements were observed in all MBL clones. The most commonly rearranged IgVH genes were 3–07 (3 MBL clones), 3–15 (3), and 4–34 (3). No VH1 family gene rearrangements were observed. In one individual, a VH3–07 MBL clone showed intraclonal diversification suggestive of antigen driven immunoglobulin sequence changes. Twenty productive light chain rearrangements were identified among the 16 MBL clones, with 11 Vλ and 9 Vκ genes used. We observed 6 productive rearrangements of Vλ1–51. MBL cells were bulk sorted for FISH from 9 subjects. Mono or biallelic deletion of 13q14.3 was observed in 5 subjects, the other 4 were normal. Conclusions : Our findings confirm that MBL is commonly observed among the unaffected family members from CLL kindreds. We found that some MBL clones express ZAP-70, CD38 or have unmutated IgVH genes and thus are similar to clinical CLL. The clinical outcome of these MBL clones in relation to our baseline prognostic characterization will be of interest. Small MBL clones are commonly oligoclonal. Importantly, although the immunoglobulin heavy and light chain genes rearranged in these MBL clones are all commonly used in CLL, the absence of VH1 and abundance of Vλ1–51 rearrangements do suggests differences in BCR usage between CLL and MBL. Further investigation of family associated MBL may clarify the genetics and immunobiology of familial CLL.

Description: Abstract 1241 Poster Board I-263 Background and Significance Monoclonal B lymphocytosis (MBL) is a hematologic syndrome characterized by accumulations of clonal B lymphocytes in the peripheral blood. Most MBL have a CLL-like immunophenotype, though other, less common phenotypes are observed. Although some MBL, particularly those with MBL cell counts 〉1.9 × 109 / L, progress to CLL, “low count” MBL (

Description: Purpose: To estimate the maximum tolerated duration (MTD) of gemcitabine given as a continuous infusion in combination with fludarabine and mitoxantrone for patients with relapsed or refractory leukemia. Patients and Methods: Patients received gemcitabine at 10mg/m2/min (day 1) with fludarabine at 25mg/m2/day for 5 days (days 1–5) and mitoxantrone at 10mg/m2/day for 3 days (days 1–3). The duration of gemcitabine infusion was escalated using the modified continuous assessment method (mCRM) at 3 hour increments (3, 6, 9, 12, and 15 hours). This three-drug regimen was build upon our previous studies with fludarabine, mitoxantrone and continuous infusion gemcitabine (Blood2003;102:250b Abstract). The MTD was estimated as the duration of gemcitabine infusion in combination with fludarabine and mitoxantrone at which 33% of the patients would experience a dose limiting toxicity (DLT). DLT was defined as either neutropenia for more than 28 days with less than 5% blasts in the marrow, a non-hematologic grade 4 toxicity lasting ≥ 3 days, or a non-hematologic grade 3 toxicity lasting ≥ 7 days. Results: Ten patients with relapsed or refractory leukemia have been treated so far since Aug 2004 and fully evaluated. The median age was 55 years (range 30 – 67). The median number of prior regimens was 3 (range 1 – 5) and the median range of prior cycles was 4 (range 1 – 6). As expected, hematologic toxicity, mucositis and nausea were common but did not meet criteria for DLT in any patient. One patient had parainfluenza lung infection with alveolar hemorrhage and this was the only DLT on the study. 2/10 patients achieved CR. Both patients are alive, 20 weeks and 52 weeks later, respectively but have received further therapy in the form of chemotherapy or allogeneic stem cell transplantation. Toxicity by Duration of Gemcitabine Infusion Duration of Infusion (hrs) # of Patients with DLT/Total Probability of Toxicity at this Dose Probability that Dose is MTD 3 0/1 0.001 0.0 6 0/2 0.009 0.005 9 0/3 0.1 0.22 12 1/4 0.36 0.59 15 0/0 0.6 0.18 Conclusion: Only one patient on this study had a DLT. This combination therapy is myelotoxic and has some anti-leukemia activity with 2/10 patients achieving CR. The duration of gemcitabine infusion as part of the above three drug regimen will be studied further on this ongoing study to more accurately estimate the MTD and determine if phase II trials are warranted.

Description: B cell chronic lymphocytic leukemia (CLL), the most common subtype of leukemia in the United States of America and in Europe, is treatable but incurable. New drugs are needed for its management. Phosphodiesterase inhibitors (PDEi) block catabolism of cyclic nucleotides resulting in accumulation of cellular cAMP and cGMP. These PDEi also decrease production of inflammatory cytokines such as tumor necrosis factor. Furthermore, they inhibit expression of inducible nitric oxide synthase (NOS2) mRNA and NO production. Researchers have previously noted that nonspecific PDE inhibitors such as theophylline as well as a relatively specific PDE4 inhibitor (rolipram) cause CLL cell death in vitro, while relatively sparing normal peripheral blood mononuclear cells (PBMC). The purpose of this study was to evaluate the effectiveness of CD160130 in the killing of freshly isolated CLL cells in vitro. CD160130 is a novel, orally available heterocyclic pyrimido-indole derivative that is relatively PDE4-specific. Patients were from the V.A. and Duke University Medical Centers, and normal controls were from the community. Control normal PBMC were isolated by ficoll-Hypaque centrifugation, and CLL cells were purified using negative selection with antibodies. We determined cytotoxicity using the MTS colorimetric assay. Samples from 10 CLL patients (6 male and 4 female) and 10 normal controls were examined. Nine of 10 patients were stage 0 at presentation, and 1 was stage 2. They had been followed 6.1 yr (median; range 0.7–19.1 yr). One of 10 was CD38 positive, and 6 of 10 were Zap-70 positive. Of nine analyzed, one had unmutated IgVH gene, and 9 were mutated. Six patients had not been treated, and 4 had been treated with chlorambucil, fludarabine, and/or rituximab. Four had normal cytogenetics by FISH analysis; one had trisomy 12; three had 13q14 del; and one had 17p del. Of seven determined, two had elevated CLL cell lipoprotein lipase mRNA elevated. CD160130 induced cell death in a dose-dependent fashion in all patients’ samples, with a mean cytotoxicity of 96% at 12.5 uM. The mean ED50 for killing was 233 nM in media with FBS and 314 nM in serum-free medium, while that for PBMC was higher at 7500 nM with FBS and 5210 nM with serum-free medium. The agent was 32.2 fold more potent for killing of CLL cells compared to PBMC in medium with FBS and 16.6 fold more potent for CLL cells in serum-free medium. In summary, the PDE4 inhibitor CD160130 potently kills freshly isolated CLL cells in vitro in the presence or absence of serum. The killing is relatively selective for CLL cells compared to normal PBMC. In vivo trials of CD160130 in patients with CLL should help determine the toxicity and efficacy in patients.

Description: Background: Although most malignancies are associated with decreased numbers of circulating T cells, in CLL they are elevated 2 to 4 times normal. Rather than promoting an anti-tumor response, this increased population of T cells may contribute to a tumor microenvironment that fosters progression of the malignant clone. Immunocompetent individuals show a wide repertoire of antigen specificity in both CD4+ and CD8+ T cells, but the T cell repertoire is significantly restricted in CLL. This restriction of the T cell repertoire may be an important cause of infectious morbidity in patients with CLL. To better understand these T cell abnormalities, we enumerated T cell subsets and determined T cell receptor diversity in 18 untreated patients with CLL. Methods: T cell subsets were enumerated from peripheral blood using highly sensitive 6-color flow cytometry. The T cell repertoire was determined for 23 T cell receptor variable β chain families (TCRvβ) in purified CD4+ and CD8+ T cells. These T cell subsets were considered separately because differential restriction of the CD4+ and CD8+ subsets has been reported previously. A PCR-based spectratype assay was used to analyze the length distribution of the TCR complementarity-determining region 3 (CDR3). A limitation of prior reports using spectratype assays was that adequately complex statistical models did not exist to simultaneously analyze the highly diverse vβ families. We addressed this limitation by using a recently-developed statistical method for spectratype analysis (Bioinformatics. 21:3394–400). Briefly, for each vβ family, the divergence from an expected reference distribution was calculated. A divergence coefficient was determined for each vβ family, and the mean divergence of all 23 vβ families was calculated. This allowed for statistical comparisons among individual patients and specific vβ families. To our knowledge, we are the first group to apply this powerful methodology to the analysis of T cell repertoires in patients with CLL. Results: We found both the CD4+ and CD8+ subsets to be expanded (mean #/μL ± SD: 1134 ± 646 and 768 ± 716, respectively; reference normal CD4+ range 401–1532, CD8+ 152–838). The absolute number of CD4+ and CD8+ T cells was greater in patients with higher absolute CLL lymphocyte counts (p = 0.018, r2 = 0.30, and p = 0.23, r2 = 0.09, respectively, linear regression). The CD4:CD8 ratio was lower in IgVH unmutated subjects (mutated 2.6, umutated 1.7, p = 0.09, two-tailed t-test assuming unequal variances). Though prior reports have disagreed on whether CD4+ or CD8+ subsets show greater restriction of clonality, we observed striking clonal restriction of CD8+ but not CD4+ T cells (p 〈 1×10−7, 2 sided t-test assuming unequal variances). There was a trend toward greater restriction of the CD8+ subset among patients with IgVH unmutated and Zap70+ CLL, but there was no correlation with lymphocyte doubling time. Conclusions: In this cohort of 18 untreated patients with CLL, there was a greater proportional increase compared to reference standards of CD8+ versus CD4+ T cells. However, the increase in CD4+, but not CD8+, T cell numbers was significantly correlated to total CLL lymphocyte count. This observation suggests that expansion of the CD4+ T cell pool observed in CLL is proportional to leukemic burden. The restriction of TCRvβ was limited to CD8+ T cells and that this effect was independent of the size of the abnormal clone. Taken together, these findings suggest different mechanisms of dysregulation of CD4+ and CD8+ T cell subsets in CLL.

Description: Background and Significance : Even though we have treatments for CLL, it remains an incurable leuke mia. We need new and better treatments for this disease. The Akt kinase is usually constitutively acti vated (phosphorylated) in CLL, and it acts to maintain CLL cell viability. Chromosome deletion at 11q22–23 is frequently seen in CLL, and this cytogenetic abnormality portends a bad prognosis. The PPP2R1B gene that encodes the Ab constant regulatory subunit of the tumor suppressor protein phos phatase 2a (PP2a) is within the deleted segment in CLL patients with deleted 11q22–23. The resulting underexpression noted in those with deleted 11q22–23 leads to decreased PP2a activity in CLL cells. PP2a is important in deactivation of Akt, the mitogen activated protein kinases (MAPK) p38, JNK, ERK, and nuclear factor kB (through IkK). We have developed apolipoprotein E-mimetic therapeutic peptides that potently decrease phosphorylation of Akt, decrease TNF and nitric oxide (NO) and NO synthase (NOS) expression, and display anti-inflammatory activity in vitro and in vivo. NOS is overexpressed in CLL, and its product NO inhibits CLL cell apoptosis. Methods : Patients were from the V.A. and Duke University Medical Centers, and normal controls were from the community. Control normal PBMC were isolated by ficoll-Hypaque centrifugation, and CD19+ CLL or normal B cells were purified using negative selection with antibodies. We determined cytotoxicity using the MTS colorimetric assay. The apoE-mimetic peptides were prepared by chemical synthesis. Results : The apoE-mimetic COG compounds are peptides of 10 to 34 amino acids derived from the ligand-binding region of the apolipoprotein E holoprotein. Samples from 6 early stage CLL patients and 11 normal individuals were examined. Five of 6 patients were Rai stage 0 at presentation, and one was stage 1. They had been followed 5.6 yr (median; range 1.9–10.6 yr). Five of 6 were CD38 negative, and 2 of 6 were Zap-70 positive. Of 5analyzed, all had mutated IgVH gene. Five of 6 patients had not been treated. Of 6 peptides examined, all displayed some cytotoxicity for CLL cells in vitro. Peptide COG 112 was the most potent, while the control peptide with an inverted sequence (COG 056) had very little or no activity (Table). CLL PBMC Agent ED50 (nM) ED50 range (n) ED50 (nM) ED50 range (n) COG 112 (active) 215 64 to 351 (6) 5,150 1,100 to 〉12,500 (6) COG 056 (control) 13,546 2771 to 20,418 (6) 〉25,000 20,470 to 〉25,500 (6) COG 112 induced cell death in a dose-dependent fashion in all patients’ samples.The ED50 of COG 112 for normal B cells was very high (〉 24,400 nM). COG 112 was approximatel 24 to 116 fold more potent for killing of CLL cells compared to normal PBMC or purified B cells. In vivo studies in normal mice using COG 112 revealed no toxicity even with doses of 100 mg/kg. Conclusions : ApoE mimetic peptides kill CLL cells in vitro with high efficacy and potency (ED50s in the low nanomolar range). The cytotoxicity is very specific for CLL cells compared to normal PBMC and B cells (24 to 116 fold more potent for CLL cells). Preliminary studies show that the peptide is nontoxic in vivo in normal mice. In vivo trials with apoE peptides in patients with CLL should help determine the toxicity and efficacy in patients.

Description: The standard induction chemotherapy for patients with multiple myeloma (MM) is a dexamethasone based regimen including dexamethasone alone, VAD, thalidomide+dexamethasone and other combinations. Currently the overall response rate achieved with these regimens is ≤70% and the complete remission (CR) rate is

Description: The viability of CLL cells may be dependent on the autocrine production of nitric oxide because nitric oxide synthase (NOS) inhibitors induce CLL cell apoptosis and CLL cells express inducible NOS (NOS2). Our previous study indicated that the non-specific NOS inhibitor NMMA induced CLL cell apoptosis but only at high concentrations (〉 1 mM) (Levesque et al., Leukemia17:442, 2003). Therefore, we performed the current study to identify NOS inhibitors that induce CLL cell apoptosis at lower concentrations and to understand factors that promote NOS inhibitor-induced CLL cell toxicity. We isolated and enriched CLL cells from the blood of CLL patients and cultured the CLL cells in media containing various concentrations of 21 different NOS inhibitors. We determined CLL cell viability following culture with each NOS inhibitor. We found that NOS inhibitors with specificity for neuronal NOS (NOS1) induced CLL cell death at concentrations lower than non-specific NOS inhibitors and lower than inducible NOS (NOS2) specific inhibitors. There was a weak correlation (r2 = 0.29, p = 0.1608) of the NOS1 (but not NOS2) half-maximal inhibitory concentration (IC50) of each NOS inhibitor for purified recombinant NOS and its ability to induce CLL cell death. We confirmed the specificity of the NOS inhibitors by inhibition of purified recombinant NOS1 and NOS2 enzyme activity, and we confirmed that NOS1 specific inhibitors induced CLL cell death by apoptosis. Because there was only a weak correlation of the NOS1 IC50 with NOS inhibitor induced CLL cell death, we considered whether other factors such as the Kd and hydrophobicity of each compound correlated with CLL cell death. We found that there was a direct correlation between the NOS1 (but not NOS2) dissociation constant (Kd) of NOS inhibitors and CLL cell death (r2 = 0.77, p = 0.0041) and a direct correlation of the partitioning coefficient (a measure of hydrophobicity) of each NOS inhibitor and its ability to induce CLL cell death (r2 = 0.68, p 〈 0.0001). Therefore, NOS inhibitors that bound tightly to NOS1 and were hydrophobic induced CLL cell death at lower concentrations. There was variable expression of CLL cell NOS1 mRNA (6 of 28 samples positive) and we were unable to demonstrate CLL cell expression of NOS1 protein by immunoblotting. This suggests that if NOS1 is present in CLL cells, it exists at very low levels. Taken together, we believe that low level NO production promotes CLL cell viability and that inhibition of CLL NOS induces CLL cell apoptosis. Importantly, our studies provide direction for the rational design and selection of NOS inhibitors that may be useful as CLL therapeutics.