Lorenz Truemper

Conventional chemotherapy (CHOEP-14) with rituximab or high-dose chemotherapy (MegaCHOEP) with rituximab for young, high-risk patients with aggressive B-cell lymphoma: an open-label, randomised, phase 3 trial (DSHNHL 2002-1)

BACKGROUND High-dose therapy (HDT) followed by transplantation of autologous haemopoietic stem cells is frequently done as part of first-line therapy in young patients with high-risk aggressive B-cell lymphoma. We investigated whether HDT with cytotoxic agents identical to those used for conventional therapy followed by autologous stem-cell transplantation (ASCT) improved survival outcome compared with conventional chemotherapy when rituximab was added to both modalities. METHODS We did an open-label, randomised trial comparing conventional chemotherapy (cyclophosphamide, doxorubicin, vincristine, etoposide, prednisone) and rituximab (R-CHOEP-14) with dose-escalated sequential HDT and rituximab (R-MegaCHOEP) followed by repetitive ASCT in high-risk (age-adjusted International Prognostic Index [IPI] 2 or 3) patients aged 18-60 years with aggressive B-cell lymphoma. Eligible patients received radiotherapy for bulky, extranodal disease, or both. Randomisation (1:1) used the Pocock minimisation algorithm; patients were stratified by age-adjusted IPI factors, bulky disease, and centre. The primary endpoint was event-free survival. All analyses were done on the intention-to-treat population. This trial is registered with ClinicalTrials.gov, number NCT00129090. FINDINGS 136 patients were randomly assigned to R-CHOEP-14 and 139 to R-MegaCHOEP. 130 patients in the R-CHOEP-14 group and 132 in the R-MegaCHOEP group were included in the intention-to-treat population. After a median of 42 months (IQR 29-59), 3-year event-free survival was 69·5% (95% CI 61·3-77·7) in the R-CHOEP-14 group and 61·4% (52·8-70·0) in the R-MegaCHOEP group (p=0·14; hazard ratio 1·3, 95% CI 0·9-2·0). All 128 evaluable patients treated with R-MegaCHOEP had grade 4 leucopenia, as did 48 (58·5%) of 82 patients with documented blood counts in the R-CHOEP-14 group. All 128 evaluable patients in the R-MegaCHOEP group had grade 3-4 thrombocytopenia, as did 26 (33·8%) of 77 patients in the R-CHOEP-14 group with documented blood counts. The most important non-haematological grade 3 or 4 adverse event was infection, which occurred in 96 (75·0%) of 128 patients treated with R-MegaCHOEP and in 40 (31·3%) of 128 patients treated with R-CHOEP-14. INTERPRETATION In young patients with high-risk aggressive B-cell lymphoma, R-MegaCHOEP was not superior to conventional R-CHOEP therapy and was associated with significantly more toxic effects. R-CHOEP-14 with or without radiotherapy remains a treatment option for these patients, with encouraging efficacy. FUNDING Deutsche Krebshilfe.

Intracellular ABC transporter A3 confers multidrug resistance in leukemia cells by lysosomal drug sequestration.

Multidrug resistance (MDR) seriously limits the efficacy of chemotherapy in patients with cancer and leukemia. Active transport across membranes is essential for such cellular drug resistance, largely provided by ATP-binding cassette (ABC) transport proteins. Intracellular drug sequestration contributes to MDR; however, a genuine intracellular ABC transport protein with MDR function has not yet been identified. Analyzing the intrinsic drug efflux capacity of leukemic stem cells, we found the ABC transporter A3 (ABCA3) to be expressed consistently in acute myeloid leukemia (AML) samples. Greater expression of ABCA3 is associated with unfavorable treatment outcome, and in vitro, elevated expression induces resistance toward a broad spectrum of cytostatic agents. ABCA3 remains localized within the limiting membranes of lysosomes and multivesicular bodies, in which cytostatics are efficiently sequestered. In addition to AML, we also detected ABCA3 in a panel of lymphohematopoietic tissues and transformed cell lines. In conclusion, we identified subcellular drug sequestration mediated by the genuinely intracellular ABCA3 as being a clinically relevant mechanism of intrinsic MDR.

Microarray-based genomic profiling reveals novel genomic aberrations in follicular lymphoma which associate with patient survival and gene expression status

Follicular lymphoma (FL) is characterized by a large number of chromosomal aberrations. However, their exact genomic extension and involved target genes remain to be determined. For this purpose, we used array‐based intermediate‐high resolution genomic profiling in combination with Affymetrix™ gene expression analysis. Tumor specimens from 128 FL patients were analyzed for the presence of genomic aberrations and the results were correlated to clinical data sets and mRNA expression levels. In 114 (89%) of the 128 analyzed cases, a total of 688 genomic aberrations (384 gains/amplifications and 304 losses) were detected. Frequent genomic aberrations were: −1p36 (18%), +2p15 (24%), −3q (14%), −6q (25%), +7p (19%), +7q (23%), +8q (14%), −9p (16%), −11q (15%), +12q (20%), −13q (11%), −17p (16%), +18p (18%), and +18q (28%). Critical segments of these imbalances were delineated to genomic fragments with a minimum size down to 0.2 Mb. By comparison of these with mRNA gene expression data, putative candidate genes were identified. Moreover, we found that deletions affecting the tumor suppressor gene CDKN2A/B on 9p21 were detected in nontransformed FL grade I–II. For this aberration as well as for −6q25 and −6q26, an association with inferior survival was observed.

Rituximab after lymphoma-directed conditioning and allogeneic stem-cell transplantation for relapsed and refractory aggressive non-Hodgkin lymphoma (DSHNHL R3): an open-label, randomised, phase 2 trial

BACKGROUND Allogeneic stem-cell transplantation has had limited success for patients with refractory and relapsed aggressive B-cell or T-cell lymphoma. We investigated the effect of adding rituximab to standard prophylaxis for graft-versus-host disease after transplantation and estimated overall survival when using a lymphoma-directed myeloablative conditioning regimen. METHODS We did this randomised, open-label, phase 2 study at seven German transplantation centres. We enrolled patients with aggressive B-cell or T-cell lymphoma and primary refractory disease, early relapse (<12 months after first-line treatment), or relapse after autologous transplantation. Conditioning with fludarabine (125 mg/m(2)), busulfan (12 mg/kg oral or 9·6 mg/kg intravenous), and cyclophosphamide (120 mg/kg) was followed by allogeneic stem-cell transplantation. Patients were randomly assigned (1:1) to receive rituximab (375 mg/m(2) on days 21, 28, 35, 42, 175, 182, 189, and 196) or not. Allocation was done with a centralised computer-generated procedure; patients were stratified by histological subtype (B-cell vs T-cell lymphoma) and donor match (HLA-identical vs non-identical). Neither investigators nor patients were masked to allocation. The primary endpoints were the incidence of acute graft-versus-host disease grade 2-4 in each treatment group and overall survival at 1 year in both groups combined. All analyses were done for the intention-to-treat population. The study is registered with ClinicalTrials.gov, number NCT00785330. FINDINGS Between June 16, 2004, and March 24, 2009, we screened 86 patients and enrolled 84; 42 were randomly assigned to each group. The cumulative incidence of grade 2-4 acute graft-versus-host disease was 46% (95% CI 32-62) in the rituximab group and 42% (95% CI 29-59) in the no rituximab group (hazard ratio [HR] 0·91, 95% CI 0·52-1·60; p=0·74). Overall survival at 1 year for the whole study population was 52% (95% CI 41-62). Grade 4 haematological toxic effects and grade 3 alopecia occurred in all patients. The most common non-haematological grade 5 toxic effects were pneumonia (nine in the no rituximab group vs ten in the rituximab group) and other infections (seven vs four). INTERPRETATION The lymphoma-directed myeloablative conditioning regimen developed here is promising for patients with refractory and relapsed aggressive B-cell and T-cell lymphomas. However, the addition of rituximab did not affect the incidence of graft-versus-host disease or overall survival. FUNDING Hoffmann-La Roche, Amgen, Astellas Pharma.

ABC transporter A3 facilitates lysosomal sequestration of imatinib and modulates susceptibility of chronic myeloid leukemia cell lines to this drug

Resistance to imatinib is a well-known clinical phenomenon. The intracellular protein ABC transporter A3 detoxifies agents by sequestering them in lysosomes. Here the authors examine A3 mediated lysomal sequestration in chronic myeloid leukemia cell lines. Background Inhibition of BCR-ABL tyrosine kinase activity has evolved as a mainstay of therapy for patients with chronic myeloid leukemia. However, a fraction of leukemic cells persists under targeted therapy and can lead to disease progression on cessation of treatment. Design and Methods We analyzed bone marrow progenitor cells with the side population phenotype, and characterized the role of the intracellular ABC transporter A3 in imatinib detoxification. Results BCR-ABL-positive leukemic cells contribute to the side population cell compartment in untreated patients. Such leukemic side population cells, as well as CD34-positive progenitors from chronic myeloid leukemia samples, strongly express the intracellular ABCA3. Functionally, ABCA3 levels are critical for the susceptibility of chronic myeloid leukemia blast cell lines to specific BCR-ABL inhibition by imatinib. The transporter is localized in the limiting membrane of lysosomes and multivesicular bodies, and intracellular [14C]-labeled imatinib accumulates in such organelles. The lysosomal storage capacity increases with ABCA3 expression, thus regulating imatinib sequestration. Conclusions The intracellular ABC transporter A3 is expressed in chronic myeloid leukemia progenitor cells and may contribute to intrinsic imatinib resistance by facilitating lysosomal sequestration in chronic myeloid leukemia cells.

Optimization of Rituximab for the Treatment of Diffuse Large B-Cell Lymphoma (II): Extended Rituximab Exposure Time in the SMARTE-R-CHOP-14 Trial of the German High-Grade Non-Hodgkin Lymphoma Study Group

PURPOSE To study pharmacokinetics, toxicity, and efficacy of prolonged rituximab exposure in elderly patients with diffuse large B-cell lymphoma (DLBCL). PATIENTS AND METHODS In the SMARTE-R-CHOP-14 trial, rituximab 375 mg/m(2) was administered, together with six cycles of rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone on a 14-day schedule (6×R-CHOP-14), on days -4, 0, 10, 29, 57, 99, 155, and 239. Pharmacokinetics and outcome were to be compared with those of patients who had received 6×R-CHOP-14 in combination with eight 2-week applications of rituximab in the RICOVER-60 (Rituximab With CHOP Over Age 60 Years) trial. RESULTS The complete response (CR)/unconfirmed CR rate was 85% in 189 evaluable patients, 90% for 90 good-prognosis patients (International Prognostic Index [IPI], 1 or 2), and 81% for 99 poor-prognosis patients (IPI, 3 to 5); 3-year event-free survival (EFS) was 71%, 75%, and 67%, respectively; and 3-year overall survival (OS) was 84%, 88%, and 80%, respectively, with no differences between men and women. The preplanned historical comparison with 306 RICOVER-60 patients (good prognosis, n = 183; poor prognosis, n = 123) revealed no outcome differences for all and good-prognosis patients; however, the longer exposure time in SMARTE-R-CHOP-14 compared with RICOVER-60 was associated with better 3-year EFS (67% v 54%) and OS (80% v 67%) in poor-prognosis patients. CONCLUSION Extended rituximab exposure compared with eight 2-week applications in combination with 6×R-CHOP-14 significantly improved outcome of elderly poor-prognosis patients without increasing toxicity. To our knowledge, results obtained with the SMARTE-R-CHOP-14 rituximab schedule are the best reported for elderly patients with DLBCL to date. In the subgroup of poor-prognosis patients treated with extended rituximab exposure, the outcome seemed superior to that of a similar historical cohort of patients treated with 6×R-CHOP-14 plus 2-week rituximab, with similar toxicity. A randomized comparison of the two schedules is warranted.

Pathway activation patterns in diffuse large B-cell lymphomas.

Deregulation of cell signaling pathways controlling cell growth and cell survival is a common feature of all cancers. Although a core repertoire of oncogenic mechanisms is widely conserved between various malignancies, the constellation of pathway activities can vary even in patients with the same malignant disease. Modern molecularly targeted cancer drugs intervene in cell signaling compensating for pathway deregulation. Hence characterizing tumors with respect to pathway activation will become crucial for treatment decisions. Here we have used semi-supervised machine learning methodology to generate signatures of eight oncogene-inducible pathways, which are conserved across epithelial and lymphoid tissues. We combined them to patterns of pathway activity called PAPs for pathway activation patterns and searched for them in 220 morphologically, immunohistochemically and genetically well-characterized mature aggressive B-cell lymphomas including 134 cases with clinical data available. Besides Burkitt lymphoma, which was characterized by a unique pattern, the PAPs identified four distinct groups of mature aggressive B-cell lymphomas across independent gene expression studies with distinct biological characteristics, genetic aberrations and prognosis. We confirmed our findings through cross-platform analysis in an independent data set of 303 mature aggressive B-cell lymphomas.

Reduced intensity conditioning and allogeneic stem cell transplantation after salvage therapy integrating alemtuzumab for patients with relapsed peripheral T-cell non-Hodgkin's lymphoma

Reduced intensity conditioning and allogeneic stem cell transplantation after salvage therapy integrating alemtuzumab for patients with relapsed peripheral T-cell non-Hodgkins lymphoma

Nuclear trapping through inhibition of exosomal export by indomethacin increases cytostatic efficacy of doxorubicin and pixantrone

Purpose: Although R-CHOP–based immunochemotherapy cures significant proportions of patients with aggressive B-cell lymphoma, tumor cell susceptibility to chemotherapy varies, with mostly fatal outcome in cases of resistant disease. We and others have shown before that export of cytostatic drugs contributes to drug resistance. Now we provide a novel approach to overcome exosome-mediated drug resistance in aggressive B-cell lymphomas. Experimental Design: We used well-established centrifugation protocols to purify exosomes from DLBCL cell lines and detected anthracyclines using FACS and HPLC. We used shRNA knockdown of ABCA3 to determine ABCA3 dependence of chemotherapy susceptibility and monitored ABCA3 expression after indomethacin treatment using qPCR. Finally, we established an in vivo assay using a chorioallantoic membrane (CAM) assay to determine the synergy of anthracycline and indomethacin treatment. Results: We show increased efficacy of the anthracycline doxorubicin and the anthracenedione pixantrone by suppression of exosomal drug resistance with indomethacin. B-cell lymphoma cells in vitro efficiently extruded doxorubicin and pixantrone, in part compacted in exosomes. Exosomal biogenesis was critically dependent on the expression of the ATP-transporter A3 (ABCA3). Genetic or chemical depletion of ABCA3 augmented intracellular retention of both drugs and shifted the subcellular drug accumulation to prolonged nuclear retention. Indomethacin increased the cytostatic efficacy of both drugs against DLBCL cell lines in vitro and in vivo in a CAM assay. Conclusions: We propose pretreatment with indomethacin toward enhanced antitumor efficacy of anthracyclines and anthracenediones. Clin Cancer Res; 22(2); 395–404. ©2015 AACR.

MDM2 gene SNP309 T/G and p53 gene SNP72 G/C do not influence diffuse large B-cell non-Hodgkin lymphoma onset or survival in central European Caucasians

BackgroundSNP309 T/G (rs2279744) causes higher levels of MDM2, the most important negative regulator of the p53 tumor suppressor. SNP72 G/C (rs1042522) gives rise to a p53 protein with a greatly reduced capacity to induce apoptosis. Both polymorphisms have been implicated in cancer. The SNP309 G-allele has recently been reported to accelerate diffuse large B-cell lymphoma (DLBCL) formation in pre-menopausal women and suggested to constitute a genetic basis for estrogen affecting human tumorigenesis. Here we asked whether SNP309 and SNP72 are associated with DLBCL in women and are correlated with age of onset, diagnosis, or patients survival.MethodsSNP309 and SNP72 were PCR-genotyped in a case-control study that included 512 controls and 311 patients diagnosed with aggressive NHL. Of these, 205 were diagnosed with DLBCL.ResultsThe age of onset was similar in men and women. The control and patients group showed similar SNP309 and SNP72 genotype frequencies. Importantly and in contrast to the previous findings, similar genotype frequencies were observed in female patients diagnosed by 51 years of age and those diagnosed later. Specifically, 3/20 female DLBCL patients diagnosed by 51 years of age were homozygous for SNP309 G and 2/20 DLBCL females in that age group were homozygous for SNP72 C. Neither SNP309 nor SNP72 had a significant influence on event-free and overall survival in multivariate analyses.ConclusionIn contrast to the previous study on Ashkenazi Jewish Caucasians, DLBCL in pre-menopausal women of central European Caucasian ethnicity was not associated with SNP309 G. Neither SNP309 nor SNP72 seem to be correlated with age of onset, diagnosis, or survival of patients.