Biomedical subjects

N C Munshi

Publications and source records attributed to N C Munshi.

At least 19 recordsLinked to original sources

PubMed2006

Didox, a ribonucleotide reductase inhibitor, induces apoptosis and inhibits DNA repair in multiple myeloma cells.

Ribonucleotide reductase (RR) is the enzyme that catalyses the rate-limiting step in DNA synthesis, the production of deoxynucleotides. RR activity is markedly elevated in tumour tissue and is crucial for cell division. It is therefore an excellent target for cancer chemotherapy. This study examined the anti-myeloma activity of Didox (3,4-Dihydroxybenzohydroxamic acid), a novel RR inhibitor (RRI). Our data showed that Didox induced caspase-dependent multiple myeloma (MM) cell apoptosis. Didox, unlike other RRIs that mainly target the pyrimidine metabolism pathway, targets both purine and pyrimidine metabolism pathways in MM, as demonstrated by transcriptional profiling using the Affymetrix U133A 2.0 gene chip. Specifically, a >or=2-fold downregulation of genes in these anabolic pathways was shown as early as 12 h after exposure to Didox. Furthermore, apoptosis was accompanied by downregulation of bcl family proteins including bcl-2, bcl(xl), and XIAP. Importantly, RR M1 component transcript was also downregulated, associated with decreased protein expression. Genes involved in DNA repair mechanisms, specifically RAD 51 homologue, were also downregulated. As Didox acts on MM cells by inhibiting DNA synthesis and repair, combination studies with melphalan, an agent commonly used in MM, were performed. A strong in vitro synergism was shown, with combination indices of <0.7 as determined by the Chou-Talalay method. These studies therefore provide the preclinical rationale for evaluation of Didox, alone and in combination with DNA-damaging agents, to improve patient outcome in MM.

Antineoplastic Agents↗

PubMed2005

Tumor antigen immunization of sibling stem cell transplant donors in multiple myeloma.

The unique antigenic determinants (idiotype (Id)) of the immunoglobulin secreted by myeloma tumor can serve as a tumor-specific antigen for active immunotherapy. Our objective was to induce tumor-specific T-cell immunity in bone marrow transplant (BMT) donors to enhance antitumor effects of allografts. We vaccinated five HLA-matched sibling donors with myeloma Id proteins isolated from recipient plasma before bone marrow harvest. Recipients were administered booster Id immunizations following transplantation. Vaccination induced donor Id and carrier-specific cellular and/or humoral immune responses. Two recipients died within 30 days of BMT from transplant-related complications. Id and carrier-specific T-cell responses were detected in all three remaining patients post-, but not pre-BMT and persisted for 18 months. All three surviving patients converted from partial to complete responses following BMT. Two of the three patients remain disease-free 7 years and 8 years after BMT, and the third died of renal failure after 5.5 years while in complete remission from myeloma. Our results suggest that myeloma Id vaccination induces specific T-cell immunity in healthy donors which may be transferable by BMT, is associated with prolonged disease-free survival of recipients, and may represent a general strategy to enhance graft-versus-tumor effect in other malignancies for which defined tumor-specific antigens exist.

Adult↗

PubMed2005

Antimyeloma activity of two novel N-substituted and tetraflourinated thalidomide analogs.

Thalidomide alone or in combination with steroids has significant activity in multiple myeloma (MM). However, given its teratogenic potential, analogs have been synthesized, retaining the anti-MM activity without these side effects. We examined the anti-MM activity of two thalidomide analogs, CPS11 and CPS49. Direct cytotoxicity of the drugs on myeloma cell lines and patient myeloma cells was examined using thymidine uptake. Tumor cell apoptosis was evaluated by flow cytometry as well as Western blotting for caspase and PARP cleavage. Cellular signaling events were examined by immunoblotting for phosphorylated proteins. Both drugs inhibit proliferation of several MM cell lines sensitive and resistant to conventional therapies. They decrease secretion of IL-6, IGF, and VEGF by marrow stromal cells. Importantly, they inhibit proliferation of MM cells adherent to stromal cells. These drugs induce caspase-mediated apoptosis in MM cell lines, as well as patient MM cells. They inhibit the PI3K/Akt and JAK/STAT (signal transducers and activators of transcription) pathways in MM cells and are antiangiogenic in matrigel-based assays. CPS11 and CPS49 have potent antimyeloma activity and can overcome protective effects of the tumor microenvironment. They have potent antiangiogenic activity and direct effect on bone marrow stroma. These encouraging preclinical data provide the basis for further evaluation in the clinic.

Angiogenesis Inhibitors↗

PubMed2003

Role for high-dose therapy with autologous hematopoietic stem cell support in Waldenstrom's macroglobulinemia.

Despite effectiveness of standard chemotherapy regimens, complete responses are infrequent in Waldenstrom's macroglobulinemia (WM) and there are no cures. Since WM shares certain biological and clinical features with myeloma, including responsiveness to alkylating agents, evaluation of high-dose therapy (HDT) with transplant, which is effective in myeloma, is an obvious next step in an effort to achieve high response rates and improve survival. Due to the indolent nature of the disease and older patients with comorbidities, such evaluations have been infrequent in the past. We have evaluated the safety and efficacy of high-dose melphalan with peripheral blood stem cell (PBSC) support in eight patients between the ages of 45 and 69 years with WM. Adequate numbers of stem cells were collected in six patients; however, two patients with more extensive prior fludarabine therapy failed to collect adequate cells and required a second attempt at stem cell collection. Seven patients were treated with melphalan 200 mg/m(2), including two patients who received tandem transplants; one patient received melphalan 140 mg/m(2) with total body irradiation (TBI). There was no treatment-related mortality and toxicities were manageable. Recovery of bone marrow after transplant was prompt except in one patient with extensive prior use of fludarabine. All the eight patients achieved at least partial response (PR), including one complete response (CR). Five patients are alive and with out relapse (77+ to 6+ months post-transplant). Other investigators have reported similar experience suggesting safety and efficacy of HDT in WM. However, therapy with purine analogues leads to stem cell damage with decreased ability to collect adequate numbers of stem cells. This suggests that the PBSCs should preferably be procured prior to extensive use of purine analogues. Future strategies in WM will include a plan to evaluate the role of HDT along with biological agents, role of purging using rituximab, post-HDT maintenance strategies (including immunotherapy), and evaluation of nonmyeloablative regimens containing fludarabine to achieve higher response rates and improve survival.

Aged↗

PubMed2002

Clinical activity of arsenic trioxide for the treatment of multiple myeloma.

Arsenic has been used since ancient times as a therapeutic agent. However, until recently its use in modern medicine has been restricted to the treatment of a limited number of parasitic infections. In the early 1990s, reports from China described impressive results with arsenic trioxide in patients with de novo, relapsed, and refractory acute promyelocytic leukemia (APL). Other investigators subsequently confirmed these results leading to approval of its use for relapsed or refractory APL in the United States. Investigations of this agent have demonstrated that its efficacy in APL and preclinical tumor models is dependent upon a number of mechanisms, including induction of apoptosis, effects on cellular differentiation, cell cycling, and tumor angiogenesis. Subsequent preclinical studies showed significant activity of arsenic trioxide in multiple myeloma (MM). Based on this, in a phase II trial, we have evaluated the activity of arsenic trioxide in 14 patients with relapsed MM, refractory to conventional salvage therapy. With the dose and schedule used, treatment with arsenic trioxide produced responses in three patients and prolonged stable disease in a fourth patient, with the longest response lasting 6 weeks. Although treatment was reasonably well tolerated, in these patients with extensive prior therapy, 11 developed cytopenia, five associated with infectious complications and three developed deep vein thromboses. The results of this small trial support further investigation of this novel drug for the treatment of patients with relapsed or refractory MM.

Adult↗

PubMed2001

Dual level inhibition of E2F-1 activity by adeno-associated virus Rep78.

E2F-1, a major cellular transcription factor, plays a pivotal role in regulating the cell cycle. The activity of E2F-1 is negatively regulated by its interaction with retinoblastoma protein (pRB), and disruption of the pRB-E2F-1 complex, a hallmark of cellular transformation by DNA tumor viruses, leads to cell proliferation. Adeno-associated virus-2 (AAV) is known to have onco-suppressive properties against DNA tumor viruses. Here we provide, for the first time, the molecular basis for antioncogenic activity of AAV. Rep78, a major regulatory protein of AAV, interacts at the protein level with E2F-1 and stabilizes the pRB-E2F-1 complex. At the DNA level, Rep78 binds to a putative site on the E2F-1 promoter and down-regulates the adenovirus-induced E2F-1 transcription. This dual level of Rep78 activity leads to decreased cellular levels of free E2F-1, leading to its onco-suppressive properties.

Adenovirus E1A Proteins↗

PubMed2001

Increased bone marrow microvessel density in newly diagnosed multiple myeloma carries a poor prognosis.

Solid organ tumors associated with neoangiogenesis, as measured by increased microvessel density (MVD), have poorer prognoses. A similar observation of increased MVD has been made in hematologic malignancies; however, its prognostic significance remains unknown. We investigated changes in MVD in 122 newly diagnosed multiple myeloma patients uniformly treated according to the "Total Therapy" protocol (remission induction followed by tandem autotransplants and interferon maintenance) from a set of 231 patients. MVD was measured as mean of 10 fields (MVD) and the single highest field (SHF) on anti-CD34-stained Zenker-fixed paraffin-embedded bone marrow biopsy sections at 400x magnification. MVD was markedly elevated in this population, with a median of 4.4 vessels/field (range, 0.6 to 55.7), and SHF was 13 vessels/field (range, 2 to 80). When compared to 54 patients with less than 4 MVD, 67 patients with mean MVD of greater than 4 had a significantly inferior median duration of event-free survival (EFS) (2.7 v 4.3 years; P =.03), overall survival (OS) (4.3 v 7.9+ years, P =.006), and median complete response (CR) duration (2.2 v 6.8+ years, P=.003). A similarly significant unfavorable relationship to EFS and OS was present for SHF greater than 13. On multivariate analysis of other previously recognized prognostic factors (beta(2)-microglobulin [beta2M], C-reactive protein [CRP], and Bartl grade; and deletion 13), MVD < or = 4 emerged as a major favorable prognostic variable for OS followed by CRP < or = 4, P=.006. Thus, tumor-associated angiogenesis as reflected by MVD is a biologically relevant and important prognostic feature that can be targeted by antiangiogenesis therapy such as thalidomide, which has remarkable antitumor activity in advanced and refractory multiple myeloma.

Bone Marrow↗

PubMed2001

Dendritic cells derived from multiple myeloma patients efficiently internalize different classes of myeloma protein.

Myeloma protein is a unique tumor antigen that can be used to devise tumor-specific vaccination strategies. As dendritic cells (DCs) are extremely potent at inducing T-cell responses, clinical protocols have been designed using myeloma protein-pulsed DCs to elicit anti-tumor cell responses in vivo. To optimize antigen pulsing of DCs, we investigated mechanisms of antigen uptake and evaluated various laboratory parameters including class of myeloma protein, antigen exposure time, and DC maturational stage.DCs were generated by culturing peripheral blood stem cells from myeloma patients in granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin-4 (IL-4). Myeloma proteins were labeled with fluorescein isothiocyanate (FITC) and internalization of protein by DCs was measured by flow cytometry.IgG, IgA, and free-kappa light chain myeloma proteins were all rapidly internalized by DCs in a time-dependent fashion. Maturation of DCs with tumor necrosis factor-alpha (TNF-alpha) resulted in diminished uptake. Endocytosis of myeloma protein by DCs was primarily mediated by fluid-phase macropinocytosis based on morphology, nonsaturable uptake kinetics, and sensitivity to drugs that inhibit membrane ruffling. Pulse-chase experiments revealed that the majority of internalized myeloma protein disappeared within 4 hours but was retained in the presence of chloroquine, indicating antigen processing had occurred. Cultured DCs from myeloma patients are functional and can efficiently endocytose different classes of myeloma protein by the mechanism of macropinocytosis. This demonstrates the feasibility of using all classes of myeloma protein for producing DC vaccines, and defines culture conditions for optimizing antigen loading of DCs for induction of anti-myeloma responses.

Antigen Presentation↗

PubMed2001

Expression of a free gamma heavy chain in serum following autologous stem cell transplantation for IgG kappa multiple myeloma.

A 41-year-old male with IgG kappa multiple myeloma is described. He developed a free gamma heavy chain without an accompanying light chain following high-dose chemotherapy and autologous peripheral blood stem cell transplantation. The free gamma heavy chain was detected in serum and urine specimens 2 months after transplant, and eventually evolved into an IgG kappa monoclonal protein with electrophoretic properties similar to the original myeloma protein. Although the origin of the free gamma heavy chain remains uncertain, it was most likely related to the underlying plasma cell malignancy and, therefore, was an early sign of disease relapse.

Adult↗

PubMed2001

Preceding chemotherapy, tumour load and age influence engraftment in multiple myeloma patients mobilized with granulocyte colony-stimulating factor alone.

Haematopoietic growth factors, especially granulocyte colony-stimulating factor (G-CSF), are frequently utilized alone for peripheral blood stem cell (PBSC) procurement to avoid the morbidity associated with high-dose chemotherapy (HDT). Moreover, the cytotoxic agents used may not be the most optimal therapy for the malignancy. It also makes scheduling of apheresis easier. Factors having an impact on PBSC procurement and engraftment after HDT were analysed in 117 multiple myeloma patients mobilized with G-CSF (10-16 microg/kg, median 12 microg/kg) alone using Cox regression analysis. A median of 6.2 x 10(6) CD34 cells/kg (range 0.6-34.1) were procured during leukapheresis and a median of 2.5 x 10(6) CD34 cells was infused after the first HDT (range 0.3-23.9). The only factor significantly affecting optimal PBSC procurement was duration of preceding conventional chemotherapy (P = 0.002). Granulocyte recovery was prompt in almost all patients, 75% of whom attained a granulocyte count of 0.5 x 10(9)/l by day 13 (median 11, range 7-19). However, platelet recovery to both 20 x 10(9)/l (median 12 d, range 8-50+) and 50 x 10(9)/l (median 20 d, range 7-205+) varied widely. On univariate analysis, factors influencing platelet recovery were the number of CD34 cells/kg infused, age, beta(2)-microglobulin levels, response to preceding therapy, bone marrow plasmacytosis and duration of prior therapy. Factors attaining significance on multivariate analysis included number of CD34 cells/kg infused (P = 0.007), beta(2)-microglobulin levels (P = 0.0001), most probably representing disease load, and age (P = 0.002). Patients with high tumour burden, i.e. beta(2)-microglobulin levels > 2.5 mg/l, probably benefit from chemotherapy for mobilization both in terms of cytoreduction and adequate stem cell mobilization resulting in accelerated engraftment.

Age Factors↗

PubMed2001

Multicolour spectral karyotyping identifies new translocations and a recurring pathway for chromosome loss in multiple myeloma.

Multicolour spectral karyotyping (SKY) was performed on primary tumour specimens from 100 patients with multiple myeloma (MM) that showed complex clonal chromosome aberrations not fully characterized by G-banding. In this study, SKY was able to identify or revise translocations with breakpoints involving 14q32, 11q13 or 8q24 in 32 patients (32%). Five new recurring translocations were identified, two of which involved chromosome 22. A subtle reciprocal translocation t(14;22) (q32;q11 approximately 12) was identified using SKY in two patients and a second, much larger, translocation t(11;22)(q13;q13) was identified using G-banding in three patients. A third new translocation was identified in two patients using SKY and G-banding as der(7)t(7;7)(p15 approximately 22;q22 approximately 32). Twenty-three patients (23%) showed the loss of 8p by whole-arm translocations with different whole-arm donor chromosomes. Among this group, two new recurring whole-arm translocations involving the centromeric breakpoint 8q10 were identified as der(8;20)(q10;q10) and der(8;18) (q10;q10) in three patients each. In addition, a novel pattern of three-way translocations involving the clonal evolution of the t(8;22)(q24;q11) by the subsequent loss of 8p by whole-arm translocations was found in three patients. The chromosome instability identified here demonstrates that the loss of 8p can occur by multiple whole-arm translocations, indicating a new pathway for the loss of a specific chromosome region in MM.

Chromosome Deletion↗

PubMed2001

Expression of AAV Rep proteins in SV40-transformed and untransformed cells: reciprocal interaction with host DNA synthesis.

Adeno-associated virus (AAV) inhibits the induction of host DNA synthesis by simian virus 40 (SV40) large-tumour (T) antigen, mediated through AAV-encoded 'Rep' regulatory proteins. Rep proteins are normally synthesized by AAV-infected cells only in the presence of adenovirus. However, we observed a low level of Rep protein expression in SV40 transformed cells even in the absence of helper virus. In an effort to understand the functional interaction between SV40 T antigen and regulators of AAV rep expression, we evaluated Rep protein production by cell lines transformed with various T antigen mutants known to vary in their induction of host DNA synthesis. We observed Rep protein expression proportional to SV40-induced host DNA synthesis, as measured previously for these T antigen mutants in the absence of AAV, suggesting that rep gene expression - although it opposes the oncogenic stimulation of cell cycling by SV40 - may itself be elicited by host DNA synthesis. To test this, we employed two inhibitors of DNA synthesis: hydroxyurea, which acts by depleting deoxyribose nucleotide triphosphate pools, and aphidicolin, a specific inhibitor of DNA polymerases alpha and delta. Each inhibitor markedly and significantly reduced Rep protein levels, both in immortal cells transformed by wild-type T antigen and in normal human fibroblasts, confirming the dependence of Rep protein expression on host DNA synthesis.

Antigens, Viral, Tumor↗

PubMed2001

Arsenic trioxide: an emerging therapy for multiple myeloma.

Arsenic trioxide can inhibit proliferation and induce apoptosis in multiple myeloma (MM) cells in vitro and in vivo. In addition to affecting tumor growth, arsenic trioxide has been shown to inhibit angiogenesis, suggesting that it may have significant potency in the treatment of MM. Based on these observations, the clinical efficacy of arsenic trioxide was evaluated in patients with advanced refractory MM using a fixed-dose intravenous infusion given daily for a maximum of 60 days. Nine patients were evaluable. All nine had extensive prior therapy; seven had two or more high-dose chemotherapy cycles with autologous stem cell support. All nine patients had cytogenetic abnormalities, and six had chromosome 13 deletions. Of the four patients who completed more than 30 days of arsenic trioxide infusion, two had >50% reduction in myeloma paraprotein, one had stable disease, and one progressed. Of the five patients with <30 days infusion, two had stable disease and three progressed. Thus, on an intent-to-treat basis, two of nine (23%) patients responded (>50% paraprotein reduction). The regimen was well tolerated except for development of cytopenia, which responded to G-CSF, and a grade III pulmonary complication in one patient. In summary, arsenic trioxide has activity in end-stage, high-risk myeloma and deserves further evaluation in earlier-stage disease.

Antineoplastic Agents↗

PubMed2000

Results of high-dose therapy for 1000 patients with multiple myeloma: durable complete remissions and superior survival in the absence of chromosome 13 abnormalities.

High-dose therapy (HDT) has increased complete remission (CR) rates and survival in multiple myeloma (MM). We now report on continuous CR (CCR) and associated prognostic factors in 1000 consecutive patients receiving melphalan-based tandem HDT. Five-year CCR was 52% among 112 CR patients without chromosome 13 (triangle up13) abnormalities and with beta-2-microglobulin </= 2.5 mg/L, C-reactive protein </= 4 mg/L, and pre-HDT standard chemotherapy </= 12 months. Of all 390 CR patients without triangle up13 abnormalities, 35% enjoyed 5-year CCR but none of 54 with triangle up13 abnormalities. triangle up13 abnormalities, present in overall 16%, reduced 5-year event-free survival from 20% to 0% and overall survival from 44% to 16% (both P <.0001). CR and a second HDT cycle applied within 6 months both extended event-free and overall survival significantly, justifying further pursuit of HDT, especially toward curing non-triangle up13 MM. (Blood. 2000;95:4008-4010)

Adolescent↗

PubMed1999

Interaction of adeno-associated virus Rep78 with p53: implications in growth inhibition.

Adeno-associated virus (AAV) is a nonpathogenic, single-stranded DNA virus belonging to the parvoviridae family. Onco-suppressive properties of AAV against adenovirus, a DNA tumor virus, have been well documented. Rep78, a major regulatory protein of AAV, is believed to be responsible for its antioncogenic properties. Most DNA tumor viruses disturb the cell cycle pathways by essentially abrogating the functions of p53. Here we present evidence that AAV acts as an antiproliferative agent against adenovirus by protecting the adenoviral-mediated degradation of p53 as confirmed by both Western blot analysis and immunoprecipitation analysis with anti-p53 antibody. Coimmunoprecipitation experiments revealed that the AAV Rep78 is physically bound to p53 in vivo. Furthermore, the binding of purified p53 to the AAV Rep78 affinity column confirms their interaction. These results document for the first time that the antiproliferative effects of AAV against adenovirus are mediated, at least in part, by the interaction of AAV Rep78 with p53.

Adenoviridae↗

PubMed1999

Lymphomatoid granulomatosis following autologous stem cell transplantation.

Lymphomatoid granulomatosis (LYG) is a rare angio-destructive lymphoproliferative disorder (LPD) of uncertain etiology, with prominent pulmonary involvement. Recent studies indicate that LYG is an Epstein-Barr virus (EBV)-associated B cell LPD with large numbers of background reactive T lymphocytes (T cell-rich B cell lymphoma). Although the disease frequently, but not exclusively, occurs in various immunodeficiency states, it has not been reported in association with the transient immunosuppression following autologous bone marrow/peripheral stem cell transplantation (ABM/PSCT). We describe a patient who developed lymphomatoid granulomatosis of the lung approximately 2 weeks after high-dose chemotherapy and autologous peripheral stem cell transplantation for multiple myeloma. Although molecular studies showed no evidence of EBV genome in the biopsy material, the serologic profile with high IgM titers was suggestive of primary EBV infection. Complete radiologic remission occurred following reconstitution of the patient's immune response after a 2-week course of ganciclovir treatment. Despite the apparently low frequency of LPD (both LYG and EBV-associated post-transplant lymphoma) in the ABMT setting, we believe that it should be considered in the differential diagnosis of patients whose clinical course following ABMT is complicated by fevers, in the absence of an identifiable infectious process.

Antineoplastic Combined Chemotherapy Protocols↗

PubMed1999

Bone marrow stromal cells as a vehicle for gene transfer.

Adoptive transfer of genetically modified somatic cells is playing an increasingly important role in the management of a wide spectrum of human diseases. Hematopoietic stem cells and lymphocytes have been used to transfer a variety of genes, however, they have limitations. In this study, the feasibility of retroviral gene transduction of bone marrow stromal cells, and the engraftment characteristics of these cells following infusion, was investigated in a murine transplantation model. Stromal cells derived from Balb/c mouse bone marrow were transduced with a replication-defective retrovirus containing the LacZ gene. Following three rounds of transduction, between 5 and 40% of the cells were positive for the LacZ gene. A total of 2 x 106 cells were infused into the same mouse strain. After the infusion, the LacZ gene was detected by PCR in the bone marrow, spleen, liver, kidney and lung; however, only the spleen and bone marrow samples were strongly positive. Quantitative PCR demonstrated that between 3 and 5% of spleen and bone marrow cells, and 1% of liver cells contained the LacZ gene at 3 weeks after infusion; <0.2% transduced cells were found in other organs. No difference was noted in engraftment between mice with or without irradiation before transplantation, suggesting that engraftment occurred without myeloablation. The infused transduced cells persisted for up to 24 weeks. Self-renewal of transplanted stromal cells was demonstrated in secondary transplant studies. Ease of culture and gene transduction and tissue specificity to hematopoietic organs (bone marrow, spleen, liver) is demonstrated, indicating that stromal cells may be an ideal vehicle for gene transfer.

Adoptive Transfer↗

PubMed1999

High-dose therapy with autologous haemopoietic stem cell support for Waldenström's macroglobulinaemia.

Standard doses of alkylating agents or purine analogues effect response rates of up to 50% in Waldenström's macroglobulinaemia (WM); however, complete responses are infrequent and there are no cures. We have evaluated the feasibility, safety and efficacy of high-dose chemotherapy with peripheral blood stem cell support in six patients aged 45-69 years (median 51.5) with WM; four patients relapsed after prior therapy inclusive of purine analogues and two patients proceeded with transplant after minimal therapy. Four patients mobilized adequate numbers of stem cells; however, two patients with more extensive fludarabine therapy failed to mobilize and required a second attempt at stem cell collection. Five patients were treated with melphalan 200 mg/m2, including one patient who received tandem transplants and one patient who received melphalan 140 mg/m2 with added total body irradiation (TBI). There was no treatment-related mortality and non-haematological toxicities were manageable. Engraftment was prompt except in one patient with extensive prior use of fludarabine. All the six patients achieved at least partial response (PR), including one who achieved complete response (CR). Five patients are alive and four are event-free at 52+, 15+, 12+ and 2+ months post transplant. This pilot study suggests safety and efficacy of high-dose therapy in WM and suggests that the peripheral blood stem cells should preferably be procured prior to extensive use of purine analogues.

Aged↗