Amitabha Mazumder

Emory University, Atlanta, GA, USA

Are you Amitabha Mazumder?

Claim your profile

Publications (26)153.05 Total impact

  • Article: Risk Stratification of Plasma Cell Neoplasm: Insights From Plasma Cell-Specific Cytoplasmic Immunoglobulin Fluorescence in Situ Hybridization (cIg FISH) vs. Conventional FISH.
    [show abstract] [hide abstract]
    ABSTRACT: Routine cytogenetic analysis of plasma cell neoplasms (PCNs) has a low sensitivity. Conventional fluorescence in situ hybridization (FISH) is not plasma cell (PC) specific and results are diluted by other cells in the sample. Although PC-specific FISH testing has been recommended for multiple myeloma (MM) risk stratification, eg, by combining cytoplasmic immunoglobulin (cIg) staining with FISH, the benefits of cIg FISH have never been directly demonstrated in a controlled study. Seventy-five samples from patients with PCNs were analyzed by concomitant conventional FISH and cIg FISH with probes for t(4;14), t(11;14), t(14;16), -13, 17p-, and +3. The results were compared for their reliability, specificity, and consistency. Apart from marginally improving detection threshold in samples with low PC burden, cIg FISH identified more abnormal cases (50 vs. 47 cases) and more chromosome abnormalities (113 vs. 103 events) than did conventional FISH. It differentiated del(13q) in myelodysplasia from MM. Remarkably, cIg FISH consistently identified a high percentage of abnormal PCs in all cases. It detected IGH translocation in 78% to 100% of PCs in all but 2 positive cases, whereas conventional FISH detected 0% to 46% in these cases (median, 91% vs. 9%). The abnormal cells found in patients with 17p- were 19% to 96% by cIg FISH vs. 0% to 13% by conventional FISH (median, 54% vs. 9%). Cases with insufficient PCs for cIg FISH had only normal conventional FISH results. CIg FISH improves reliability of FISH testing for PCNs by eliminating borderline results. In myelomas with an IGH translocation, myeloma cells invariably carry the abnormality.
    Clinical lymphoma, myeloma & leukemia 05/2012; 12(5):366-74.
  • Source
    Article: Elotuzumab in combination with lenalidomide and low-dose dexamethasone in relapsed or refractory multiple myeloma.
    [show abstract] [hide abstract]
    ABSTRACT: This phase I study evaluated elotuzumab, lenalidomide, and dexamethasone in patients with relapsed or refractory multiple myeloma (MM). Three cohorts were enrolled and treated with elotuzumab (5.0, 10, or 20 mg/kg intravenously) on days 1, 8, 15, and 22 of a 28-day cycle in the first two cycles, and days 1 and 15 of each subsequent cycle; lenalidomide 25 mg orally [PO] on days 1 to 21; and dexamethasone 40 mg PO weekly. Dose-limiting toxicities (DLTs) were assessed during cycle 1 of each cohort, and clinical responses were evaluated during each cycle. The first five patients received up to six cycles of therapy; subsequent patients were treated until disease progression. Twenty-nine patients with advanced MM and a median of three prior MM therapies were enrolled; 28 patients were treated, three each in the 5.0-mg/kg and 10-mg/kg cohorts and 22 in the 20-mg/kg cohort. No DLTs were observed up to the maximum proposed dose of 20 mg/kg. The most frequent grade 3 to 4 toxicities were neutropenia (36%) and thrombocytopenia (21%). Two patients experienced a serious infusion reaction (one grade 4 anaphylactic reaction and one grade 3 stridor) during the first treatment cycle. Objective responses were obtained in 82% (23 of 28) of treated patients. After a median of 16.4 months follow-up, the median time to progression was not reached for patients in the 20-mg/kg cohort who were treated until disease progression. The combination of elotuzumab, lenalidomide, and low-dose dexamethasone was generally well tolerated and showed encouraging response rates in patients with relapsed or refractory MM.
    Journal of Clinical Oncology 04/2012; 30(16):1953-9. · 18.37 Impact Factor
  • Article: A phase 1 study of IPI-504 (retaspimycin hydrochloride) in patients with relapsed or relapsed and refractory multiple myeloma.
    [show abstract] [hide abstract]
    ABSTRACT: Abstract A phase 1 study of IPI-504 (retaspimycin hydrochloride) administered intravenously twice weekly for 2 weeks at 22.5, 45, 90, 150, 225, 300 or 400 mg/m(2) followed by 10 days off-treatment was conducted to determine the safety and maximum tolerated dose (MTD) of IPI-504 in patients with relapsed or relapsed/refractory multiple myeloma (MM). Anti-tumor activity and pharmacokinetics were also evaluated. Eighteen patients (mean age 60.5 years; median 9 prior therapies) were enrolled. No dose-limiting toxicities (DLTs) were reported for IPI-504 doses up to 400 mg/m(2). The most common treatment-related adverse event was grade 1 infusion site pain (four patients). All other treatment-related events were assessed as grade 1 or 2 in severity. The area under the curve (AUC) increased with increasing dose, and the mean half-life was approximately 2-4 h for IPI-504 and its metabolites. Four patients had stable disease, demonstrating modest single-agent activity in relapsed or relapsed/refractory MM.
    Leukemia & lymphoma 08/2011; 52(12):2308-15. · 2.40 Impact Factor
  • Article: Intracranial multifocal dural involvement in multiple myeloma: case report and review of the literature.
    [show abstract] [hide abstract]
    ABSTRACT: Multiple myeloma is an incurable clonal B-cell malignancy with terminally differentiated plasma cells that accounts for 1% of all malignancies in the United States. It may present with tumors consisting of discrete masses of neoplastic monoclonal plasma cells in either bone or soft tissues. Central nervous system (CNS) involvement of myeloma is uncommon and is observed in approximately 1% of cases. It may manifest as dural myeloma or intraparenchymal infiltration, or with diffuse leptomeningeal involvement. Dural involvement of myeloma without parenchymal or leptomeningeal disease is an even rarer occurrence, with only 5 cases reported in the medical literature. There are no established treatment guidelines for CNS myelomatosis; prognosis and literature on the use of treatment modalities for this complication is reviewed herein.
    Clinical lymphoma, myeloma & leukemia 06/2010; 10(3):220-3.
  • Article: Vorinostat plus bortezomib for the treatment of relapsed/refractory multiple myeloma: a case series illustrating utility in clinical practice.
    Amitabha Mazumder, David H Vesole, Sundar Jagannath
    [show abstract] [hide abstract]
    ABSTRACT: Increasing numbers of patients are presenting with relapsed/refractory multiple myeloma (MM) following treatment with bortezomib. Therefore, there is a need for effective and well-tolerated treatment strategies after failure of bortezomib-based regimens. Vorinostat, a histone deacetylase inhibitor, has demonstrated antiproliferative and proapoptotic activity alone and in combination with bortezomib in preclinical models of MM. Preliminary results from ongoing phase I trials have demonstrated the clinical activity of vorinostat in combination with bortezomib in patients with MM. This case series reports our experience of combined vorinostat and bortezomib in 6 patients with relapsed/refractory MM after previous bortezomib. Patients received oral vorinostat 300 mg or 400 mg once daily (days 1-14) and bortezomib 1.3 mg/m2 on days 1, 4, 8, and 11 in a 21-day cycle. All patients derived clinical benefit from combined vorinostat and bortezomib, with objective response observed in 5 of the 6 patients (> or = minimal response), including 1 very good partial response; stable disease was observed in the remaining patient. Patients remained on therapy until disease progression. Combined vorinostat and bortezomib therapy was well tolerated: grade 2 nausea and diarrhea were the only adverse events reported. No patients discontinued therapy because of toxicity, and no dose adjustments were required for either agent. These results suggest that combined vorinostat and bortezomib therapy is effective in patients with relapsed/refractory MM after failure of previous bortezomib-based regimens and support further evaluation of this combination in randomized trials.
    Clinical lymphoma, myeloma & leukemia 04/2010; 10(2):149-51.
  • Article: Lenalidomide, bortezomib, and dexamethasone combination therapy in patients with newly diagnosed multiple myeloma.
    [show abstract] [hide abstract]
    ABSTRACT: This phase 1/2 study is the first prospective evaluation of lenalidomide-bortezomib-dexamethasone in front-line myeloma. Patients (N = 66) received 3-week cycles (n = 8) of bortezomib 1.0 or 1.3 mg/m(2) (days 1, 4, 8, 11), lenalidomide 15 to 25 mg (days 1-14), and dexamethasone 40 or 20 mg (days 1, 2, 4, 5, 8, 9, 11, 12). Responding patients proceeded to maintenance or transplantation. Phase 2 dosing was determined to be bortezomib 1.3 mg/m(2), lenalidomide 25 mg, and dexamethasone 20 mg. Most common toxicities included sensory neuropathy (80%) and fatigue (64%), with only 27%/2% and 32%/3% grade 2/3, respectively. In addition, 32% reported neuropathic pain (11%/3%, grade 2/3). Grade 3/4 hematologic toxicities included lymphopenia (14%), neutropenia (9%), and thrombocytopenia (6%). Thrombosis was rare (6% overall), and no treatment-related mortality was observed. Rate of partial response was 100% in both the phase 2 population and overall, with 74% and 67% each achieving very good partial response or better. Twenty-eight patients (42%) proceeded to undergo transplantation. With median follow-up of 21 months, estimated 18-month progression-free and overall survival for the combination treatment with/without transplantation were 75% and 97%, respectively. Lenalidomide-bortezomib-dexamethasone demonstrates favorable tolerability and is highly effective in the treatment of newly diagnosed myeloma. This study is registered at http://clinicaltrials.gov as NCT00378105.
    Blood 04/2010; 116(5):679-86. · 9.90 Impact Factor
  • Source
    Article: Proteasome inhibition and its therapeutic potential in multiple myeloma.
    Ajai Chari, Amitabha Mazumder, Sundar Jagannath
    [show abstract] [hide abstract]
    ABSTRACT: Due to an unmet clinical need for treatment, the first in class proteasome inhibitor, bortezomib, moved from drug discovery to FDA approval in multiple myeloma in an unprecedented eight years. In the wake of this rapid approval arose a large number of questions about its mechanism of action and toxicity as well as its ultimate role in the treatment of this disease. In this article, we briefly review the preclinical and clinical development of the drug as the underpinning for a systematic review of the large number of clinical trials that are beginning to shed some light on the full therapeutic potential of bortezomib in myeloma. We conclude with our current understanding of the mechanism of action of this agent and a discussion of the novel proteasome inhibitors under development, as it will be progress in these areas that will ultimately determine the true potential of proteasome inhibition in myeloma.
    Biologics: Targets & Therapy 01/2010; 4:273-87.
  • Article: Phase 2 study of two sequential three-drug combinations containing bortezomib, cyclophosphamide and dexamethasone, followed by bortezomib, thalidomide and dexamethasone as frontline therapy for multiple myeloma.
    [show abstract] [hide abstract]
    ABSTRACT: Novel sequential combination therapy for induction may improve the quality of response and therefore prolong survival in newly diagnosed multiple myeloma (MM) patients. We report results from a phase 2 study of two sequential three-drug combinations. Forty-four previously untreated, symptomatic MM patients received: bortezomib 1.3 mg/m(2) (days 1, 4, 8, 11), cyclophosphamide 300 mg/m(2) (days 1, 8), plus dexamethasone 40 mg (day of and day after bortezomib) for three 21-day cycles, followed by bortezomib 1.0 mg/m(2), dexamethasone 40 mg and thalidomide 100 mg daily for three cycles. Overall response rate for 42 evaluable patients was 95%, including 19% stringent complete response (sCR), 26% CR, and 57%>/= very good partial response. Twenty-two patients have undergone stem-cell transplantation. After a median follow-up of 20.9 months, five patients have died; none was induction therapy-related. Median event-free survival (EFS) and overall survival (OS) have not been reached; estimated 1-year EFS and OS rates were 81% and 91% respectively. Both three-drug combinations were well tolerated; 82% of patients completed all six cycles. Toxicities were predictable and manageable; the most-commonly reported grade 3/4 toxicity was neuropathy (11%). This novel sequential three-drug combination therapy is effective and well-tolerated in previously untreated MM patients.
    British Journal of Haematology 11/2009; 148(4):562-8. · 4.94 Impact Factor
  • Article: Multicenter, phase I, dose-escalation trial of lenalidomide plus bortezomib for relapsed and relapsed/refractory multiple myeloma.
    [show abstract] [hide abstract]
    ABSTRACT: Lenalidomide and bortezomib are active in relapsed and relapsed/refractory multiple myeloma (MM). In preclinical studies, lenalidomide sensitized MM cells to bortezomib and dexamethasone. This phase I, dose-escalation study (ie, NCT00153933) evaluated safety and determined the maximum-tolerated dose (MTD) of lenalidomide plus bortezomib in patients with relapsed or with relapsed and refractory MM. Patients received lenalidomide 5, 10, or 15 mg/d on days 1 through 14 and received bortezomib 1.0 or 1.3 mg/m(2) on days 1, 4, 8, and 11 of 21-day cycles. Dexamethasone (20mg or 40 mg on days 1, 2, 4, 5, 8, 9, 11, and 12) was added for progressive disease after two cycles. Primary end points were safety and MTD determination. Thirty-eight patients were enrolled across six dose cohorts. The MTD was lenalidomide 15 mg/d plus bortezomib 1.0 mg/m(2). Dose-limiting toxicities (n = 1 for each) were grade 3 hyponatremia and herpes zoster reactivation and grade 4 neutropenia. The most common treatment-related, grades 3 to 4 toxicities included reversible neutropenia, thrombocytopenia, anemia, and leukopenia. Among 36 response-evaluable patients, 61% (90% CI, 46% to 75%) achieved minimal response or better. Among 18 patients who had dexamethasone added, 83% (90% CI, 62% to 95%) achieved stable disease or better. Median overall survival was 37 months. Lenalidomide plus bortezomib was well tolerated and showed promising activity with durable responses in patients with relapsed and relapsed/refractory MM, including patients previously treated with lenalidomide, bortezomib, and/or thalidomide. The combination of lenalidomide, bortezomib, and dexamethasone is being investigated in a phase II study in this setting and in newly diagnosed MM.
    Journal of Clinical Oncology 09/2009; 27(34):5713-9. · 18.37 Impact Factor
  • Article: Extended follow-up of a phase 2 trial of bortezomib alone and in combination with dexamethasone for the frontline treatment of multiple myeloma.
    [show abstract] [hide abstract]
    ABSTRACT: High-quality response to multiple myeloma (MM) therapy can be predictive for improved outcomes. Novel agents may improve the depth of responses and therefore prolong survival. We report on the extended follow-up of a phase II study in frontline MM of bortezomib alone and in combination with dexamethasone. Forty-nine previously untreated, symptomatic MM patients received bortezomib 1.3 mg/m(2), days 1, 4, 8, 11, for up to six 3-week cycles. High-dose dexamethasone was added for patients not reaching either a partial response after cycle 2 or a complete response (CR) after cycle 4. The overall response rate in 48 evaluable patients was 90%, with 42% achieving at least a very good partial response, of which 19% were CR/near CR. Thirty-six patients received high-dose dexamethasone with 28 (77%) showing improved response. Twenty-seven patients have undergone successful stem-cell transplantation (SCT). After median follow-up of 49 months, 15 patients have died; median overall survival has still not been reached, with an estimated survival at 4 years of 67%. Overall survival with and without SCT was not different (P = 0.54). Grade 3/4 adverse events included neutropenia (10%), sensory neuropathy (6% grade 3), neuropathic pain (4% grade 3), and diarrhoea (4% grade 3). Bortezomib +/- dexamethasone is an effective and well-tolerated induction regimen for the frontline treatment of MM.
    British Journal of Haematology 08/2009; 146(6):619-26. · 4.94 Impact Factor
  • Article: Dendritic cells mediate the induction of polyfunctional human IL17-producing cells (Th17-1 cells) enriched in the bone marrow of patients with myeloma.
    [show abstract] [hide abstract]
    ABSTRACT: IL17-producing (Th17) cells are a distinct lineage of T helper cells that regulate immunity and inflammation. The role of antigen-presenting cells in the induction of Th17 cells in humans remains to be fully defined. Here, we show that human dendritic cells (DCs) are efficient inducers of Th17 cells in culture, including antigen-specific Th17 cells. Although most freshly isolated circulating human Th17 cells secrete IL17 alone or with IL2, those induced by DCs are polyfunctional and coexpress IL17 and IFNgamma (Th17-1 cells). The capacity of DCs to expand Th17-1 cells is enhanced upon DC maturation, and mature DCs are superior to monocytes for the expansion of autologous Th17 cells. In myeloma, where tumors are infiltrated by DCs, Th17 cells are enriched in the bone marrow relative to circulation. Bone marrow from patients with myeloma contains a higher proportion of Th17-1 cells compared with the marrow in preneoplastic gammopathy (monoclonal gammopathy of undetermined significance [MGUS]). Uptake of apoptotic but not necrotic myeloma tumor cells by DCs leads to enhanced induction of Th17-1 cells. These data demonstrate the capacity of DCs to induce expansion of polyfunctional IL17-producing T cells in humans, and suggest a role for DCs in the enrichment of Th17-1 cells in the tumor bed.
    Blood 08/2008; 112(7):2878-85. · 9.90 Impact Factor
  • Article: Inflammation-associated lysophospholipids as ligands for CD1d-restricted T cells in human cancer.
    [show abstract] [hide abstract]
    ABSTRACT: CD1d-restricted T cells have been implicated in the pathogenesis of several chronic inflammatory states. However, the nature of the specific ligands recognized by these cells in vivo in patients with inflammatory or malignant diseases remains unknown. We took a biochemical approach to directly isolate and characterize the nature of CD1d-binding ligands from the plasma of myeloma patients. Characterization of these ligands revealed several lysophosphatidylcholine (LPC) species. Human LPC-CD1d dimer binding cells are T-cell receptoralphabeta(+) T cells but predominantly Valpha24(-)Vbeta11(-). Cytokine secretion by LPC-specific T cells is skewed toward IL-13 secretion, and the frequencies of these cells are increased in myeloma patients relative to healthy donors. These data identify a distinct population of human CD1d-restricted T cells specific for inflammation-associated lysolipids and suggest a novel mechanism for inflammation mediated immune regulation in human cancer.
    Blood 07/2008; 112(4):1308-16. · 9.90 Impact Factor
  • Article: Association between renal cell carcinoma and plasma cell dyscrasias: a case series of six patients.
    [show abstract] [hide abstract]
    ABSTRACT: Multiple malignancies in the same patient are unusual. This is particularly true for patients with hematologic malignancies who have a concomitant solid tumor. We report the unexpectedly higher frequency of renal cell carcinoma (RCC) associated with plasma cell dyscrasias. We report 6 cases of RCC in our institutional database of 600 patients with plasma cell dyscrasias over the past 10 years. We discuss the possible mechanisms that predisposed these patients to a secondary malignancy.
    Clinical Lymphoma & Myeloma 06/2008; 8(3):188-90. · 1.13 Impact Factor
  • Article: Liver involvement in multiple myeloma.
    Meghana S Bhandari, Amitabha Mazumder, David H Vesole
    [show abstract] [hide abstract]
    ABSTRACT: Clinical manifestations of liver involvement in multiple myeloma (MM) are uncommon. Rare cases of MM present as acute liver disease. We report a case of a 55-year-old woman with MM who presented with painless jaundice, mild pruritus, and abnormal liver function tests resembling acute cholestatic hepatitis without the stigmata of chronic liver disease. Initial laboratories included elevated liver function tests (aspartate aminotransferase 74 U/L and alanine aminotransferase 45 U/L) and an elevated white blood cell count of 19,600 cells/microL with 33% circulating plasma cells. Myeloma parameters demonstrated an immunoglobulin G lambda monoclonal protein with lambda light-chain Bence-Jones proteinuria. Bone marrow was hypercellular with 70% plasmacytosis. A liver biopsy revealed a diffuse portal and sinusoidal infiltration of plasma cells with lambda light-chain restriction. In this report, we review the literature of liver involvement in MM.
    Clinical Lymphoma & Myeloma 10/2007; 7(8):538-40. · 1.13 Impact Factor
  • Article: Bortezomib enhances dendritic cell (DC)-mediated induction of immunity to human myeloma via exposure of cell surface heat shock protein 90 on dying tumor cells: therapeutic implications.
    [show abstract] [hide abstract]
    ABSTRACT: Most anticancer chemotherapies are immunosuppressive and induce nonimmunogenic tumor cell death. Bortezomib, a specific inhibitor of 26S proteasome, has shown clinical activity in several human tumors, including myeloma. Here we show that the uptake of human myeloma cells by dendritic cells (DCs) after tumor cell death by bortezomib, but not gamma irradiation or steroids, leads to the induction of antitumor immunity, including against primary tumor cells, without the need for any additional adjuvants. The delivery of activating signal from bortezomib-killed tumor cells to DCs depends on cell-cell contact between DCs and dying tumor cells and is mediated by bortezomib-induced exposure of heat shock protein 90 (hsp90) on the surface of dying cells. The combination of bortezomib and geldanamycin (an hsp90 inhibitor) leads to greater apoptosis of tumor cells but abrogates their immunogenicity. These data identify drug-induced exposure of endogenous heat shock proteins on the surface of dying cells as a mechanism of immunogenic death of human tumors. Specific targeting of bortezomib to tumors may enhance their immunogenicity and the induction of antitumor immunity.
    Blood 07/2007; 109(11):4839-45. · 9.90 Impact Factor
  • Source
    Article: Frequent and specific immunity to the embryonal stem cell-associated antigen SOX2 in patients with monoclonal gammopathy.
    [show abstract] [hide abstract]
    ABSTRACT: Specific targets of cellular immunity in human premalignancy are largely unknown. Monoclonal gammopathy of undetermined significance (MGUS) represents a precursor lesion to myeloma (MM). We show that antigenic targets of spontaneous immunity in MGUS differ from MM. MGUS patients frequently mount a humoral and cellular immune response against SOX2, a gene critical for self-renewal in embryonal stem cells. Intranuclear expression of SOX2 marks the clonogenic CD138(-) compartment in MGUS. SOX2 expression is also detected in a proportion of CD138(+) cells in MM patients. However, these patients lack anti-SOX2 immunity. Cellular immunity to SOX2 inhibits the clonogenic growth of MGUS cells in vitro. Detection of anti-SOX2 T cells predicts favorable clinical outcome in patients with asymptomatic plasmaproliferative disorders. Harnessing immunity to antigens expressed by tumor progenitor cells may be critical for prevention and therapy of human cancer.
    Journal of Experimental Medicine 05/2007; 204(4):831-40. · 13.85 Impact Factor
  • Article: Bortezomib disrupts tumour-dendritic cell interactions in myeloma and lymphoma: therapeutic implications.
    [show abstract] [hide abstract]
    ABSTRACT: Recent studies have shown that the interactions between tumour and dendritic cells (DCs) promote clonogenic growth of lymphoproliferative tumours, particularly myeloma. The present study showed that the proteasome inhibitor, bortezomib, disrupts this interaction. Targeting the drug to DCs was required for optimal suppression of tumour growth, including primary myeloma tumour progenitors in clonogenic assays. Bortezomib lead to dose-dependent induction of apoptosis in both myeloid and plasmacytoid DCs, and the sensitivity of DCs to bortezomib was comparable with that of tumour cells. These data suggest that disruption of tumour-DC interactions may contribute to the clinical effects of bortezomib.
    British Journal of Haematology 02/2007; 136(1):106-10. · 4.94 Impact Factor
  • Article: Engraftment syndrome after hematopoietic stem cell transplantation in multiple myeloma.
    Clinical Lymphoma & Myeloma 10/2006; 7(2):151. · 1.13 Impact Factor
  • Source
    Article: Enhancement of clonogenicity of human multiple myeloma by dendritic cells.
    [show abstract] [hide abstract]
    ABSTRACT: Infiltration by dendritic cells (DCs) is a common feature of most human tumors. Prior studies evaluating the interaction of DCs with tumors have focused largely on their immunologic properties (for review see Banchereau, J., and R.M. Steinman. 1998. Nature. 392:245-252). In this study, we show that the clonogenicity of several human tumor cell lines and primary tumor cells from myeloma patients is enhanced by their interactions with DCs. Myeloma cells cultured in the presence of DCs have an altered phenotype with an increased proportion of cells lacking terminal plasma cell differentiation marker CD138. DC-tumor interaction also leads to the up-regulation of B cell lymphoma 6 expression in myeloma cells. Effects of DCs on myeloma cells are inhibited by blockade of the receptor activator of NF-kB (RANK)-RANK ligand and B cell-activating factor-APRIL (a proliferation-inducing ligand)-mediated interactions. Together, these data suggest that tumor-DC interactions may directly impact the biology of human tumors, particularly multiple myeloma, and may be a target for therapeutic intervention.
    Journal of Experimental Medicine 09/2006; 203(8):1859-65. · 13.85 Impact Factor
  • Article: Enhancement of ligand-dependent activation of human natural killer T cells by lenalidomide: therapeutic implications.
    [show abstract] [hide abstract]
    ABSTRACT: Natural killer T (NKT) cells are CD1d-restricted glycolipid reactive innate lymphocytes that play an important role in protection from pathogens and tumors. Pharmacologic approaches to enhance NKT cell function will facilitate specific NKT targeting in the clinic. Here we show that lenalidomide (LEN), a novel thalidomide (Thal) analog, enhances antigen-specific expansion of NKT cells in response to the NKT ligand alpha-galactosylceramide (alpha-GalCer) in both healthy donors and patients with myeloma. NKT cells activated in the presence of LEN have greater ability to secrete interferon-gamma. Antigen-dependent activation of NKT cells was greater in the presence of dexamethasone (DEX) plus LEN than with DEX alone. Therapy with LEN/Thal also led to an increase in NKT cells in vivo in patients with myeloma and del5q myelodysplastic syndrome. Together these data demonstrate that LEN and its analogues enhance CD1d-mediated presentation of glycolipid antigens and support combining these agents with NKT targeted approaches for protection against tumors.
    Blood 08/2006; 108(2):618-21. · 9.90 Impact Factor