Publications

42 Publications visible to you, out of a total of 42

Abstract

Not specified

Authors: J. Meissner, D. Tichy, S. Dietrich, T. Schmitt, M. Ziepert, E. Kuhnt, T. Rixecker, M. Witzens-Harig, M. Pfreundschuh, A. D. Ho

Date Published: 3rd Apr 2014

Publication Type: Not specified

Human Diseases: lymphoma

Abstract (Expand)

Tumors are composed of phenotypically heterogeneous cell populations. The nongenomic mechanisms underlying transitions and interactions between cell populations are largely unknown. Here, we show that diffuse large B-cell lymphomas possess a self-organized infrastructure comprising side population (SP) and non-SP cells, where transitions between clonogenic states are modulated by exosome-mediated Wnt signaling. DNA methylation modulated SP-non-SP transitions and was correlated with the reciprocal expressions of Wnt signaling pathway agonist Wnt3a in SP cells and the antagonist secreted frizzled-related protein 4 in non-SP cells. Lymphoma SP cells exhibited autonomous clonogenicity and exported Wnt3a via exosomes to neighboring cells, thus modulating population equilibrium in the tumor.

Authors: R. Koch, M. Demant, T. Aung, N. Diering, A. Cicholas, B. Chapuy, D. Wenzel, M. Lahmann, A. Guntsch, C. Kiecke, S. Becker, T. Hupfeld, V. Venkataramani, M. Ziepert, L. Opitz, W. Klapper, L. Trumper, G. G. Wulf

Date Published: 3rd Apr 2014

Publication Type: Not specified

Human Diseases: diffuse large B-cell lymphoma

Abstract (Expand)

BACKGROUND: Little is known on the heterogeneity of hematotoxicity in patients receiving multicycle chemotherapy. PATIENTS AND METHODS: We analyzed data of 1399 patients with aggressive lymphoma from trials using CHOP (combination chemotherapy with cyclophosphamide, doxorubicin, vincristine and prednisone)-like therapies. Multivariate modeling was carried out for leukocytopenia, thrombocytopenia and anemia and the models were validated by two large independent datasets from trials with/without usage of the CD20-antibody rituximab. RESULTS: On the basis of these models, we are able to predict the remarkable heterogeneity of hematotoxicity and propose to use risk groups. Regarding leukocytopenia, the low toxicity risk group experienced World Health Organization grade 4 in <10% of the cycles while the high toxicity risk group in almost all cycles. For thrombocytopenia, groups were detectable with almost no grade 3 or 4 toxicity and others where two out of three cycles were affected. In a separate set of models, the first cycle toxicity was the strongest predictor for later hematotoxicity. The risk for leukocytopenia was associated with infections, antibiotic use, hospitalization and treatment-related mortality, indicating the clinical usefulness of the models. For the first time, a Web-based tool is made available to easily predict the hematotoxicity in clinical practice (www.toxcalculator.com). CONCLUSION: This analysis has implications for patient management and prophylaxis.

Authors: M. Ziepert, R. Schmits, L. Trumper, M. Pfreundschuh, M. Loeffler

Date Published: 1st Dec 2007

Publication Type: Not specified

Human Diseases: non-Hodgkin lymphoma

Abstract (Expand)

Purpose Overall survival (OS) is the definitive and best-established primary efficacy end point to evaluate diffuse large B-cell lymphoma (DLBCL) therapies, but it requires prolonged follow-up. An earlier end point assessed post-treatment would expedite clinical trial conduct and accelerate patient access to effective new therapies. Our objective was to formally evaluate progression-free survival (PFS) and PFS at 24 months (PFS24) as surrogate end points for OS in first-line DLBCL. Patients and Methods Individual patient data were analyzed from 7,507 patients from 13 multicenter randomized controlled trials of active treatment in previously untreated DLBCL, published after 2002, with sufficient PFS data to predict treatment effects on OS. Trial-level surrogacy examining the correlation of treatment effect estimates of PFS/PFS24 and OS was evaluated using both linear regression ( R(2)WLS) and Copula bivariable ( R(2)Copula) models. Prespecified criteria for surrogacy required either R(2)WLS or R(2)Copula >/= 0.80 and neither < 0.7, with lower-bound 95% CI > 0.60. Results Trial-level surrogacy for PFS was strong ( R(2)WLS = 0.83; R(2)Copula = 0.85) and met the predefined criteria for surrogacy. At the patient level, PFS strongly correlated with OS. The surrogate threshold effect had a hazard ratio of 0.89. Surrogacy was consistent across comparisons with or without rituximab and with rituximab maintenance trials. Trial-level surrogacy for PFS24 was relatively strong ( R(2)WLS = 0.77; R(2)Copula = 0.78) but did not meet prespecified criteria. At the patient level, PFS24 significantly correlated with OS. The surrogate threshold effect had an odds ratio of 1.51. Conclusion This large pooled analysis of individual patient data supports PFS as a surrogate end point for OS in future randomized controlled trials evaluating chemoimmunotherapy in DLBCL. Use of this end point may expedite therapeutic development with the intent of bringing novel therapies to this patient population years before OS results are mature.

Authors: Q. Shi, N. Schmitz, F. S. Ou, J. G. Dixon, D. Cunningham, M. Pfreundschuh, J. F. Seymour, U. Jaeger, T. M. Habermann, C. Haioun, H. Tilly, H. Ghesquieres, F. Merli, M. Ziepert, R. Herbrecht, J. Flament, T. Fu, B. Coiffier, C. R. Flowers

Date Published: 1st Sep 2018

Publication Type: Not specified

Human Diseases: diffuse large B-cell lymphoma

Abstract (Expand)

Background: Patients with diffuse large B-cell lymphoma treated with first-line anthracycline-based immunochemotherapy and remaining in remission at 2 years have excellent outcomes. This study assessed overall survival (OS) stratified by progression-free survival (PFS) at 24 months (PFS24) using individual patient data from patients with DLBCL enrolled in multi-center, international randomized clinical trials as part of the Surrogate Endpoint for Aggressive Lymphoma (SEAL) Collaboration. Patients and methods: PFS24 was defined as being alive and PFS24 after study entry. OS from PFS24 was defined as time from identified PFS24 status until death due to any cause. OS was compared with each patient's age-, sex-, and country-matched general population using expected survival and standardized mortality ratios (SMRs). Results: A total of 5853 patients enrolled in trials in the SEAL database received rituximab as part of induction therapy and were included in this analysis. The median age was 62 years (range 18-92), and 56% were greater than 60 years of age. At a median follow-up of 4.4 years, 1337 patients (23%) had disease progression, 1489 (25%) had died, and 5101 had sufficient follow-up to evaluate PFS24. A total of 1423 assessable patients failed to achieve PFS24 with a median OS of 7.2 months (95% CI 6.8-8.1) after progression; 5-year OS after progression was 19% and SMR was 32.1 (95% CI 30.0-34.4). A total of 3678 patients achieved PFS24; SMR after achieving PFS24 was 1.22 (95% CI 1.09-1.37). The observed OS versus expected OS at 3, 5, and 7 years after achieving PFS24 was 93.1% versus 94.4%, 87.6% versus 89.5%, and 80.0% versus 83.7%, respectively. Conclusion: Patients treated with rituximab containing anthracycline-based immunochemotherapy on clinical trials who are alive without progression at 24 months from the onset of initial therapy have excellent outcomes with survival that is marginally lower but clinically indistinguishable from the age-, sex-, and country-matched background population for 7 years after achieving PFS24.

Authors: M. J. Maurer, T. M. Habermann, Q. Shi, N. Schmitz, D. Cunningham, M. Pfreundschuh, J. F. Seymour, U. Jaeger, C. Haioun, H. Tilly, H. Ghesquieres, F. Merli, M. Ziepert, R. Herbrecht, J. Flament, T. Fu, C. R. Flowers, B. Coiffier

Date Published: 1st Aug 2018

Publication Type: Not specified

Human Diseases: diffuse large B-cell lymphoma

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