TY - JOUR A1 - Butt, Elke A1 - Stempfle, Katrin A1 - Lister, Lorenz A1 - Wolf, Felix A1 - Kraft, Marcella A1 - Herrmann, Andreas B. A1 - Viciano, Cristina Perpina A1 - Weber, Christian A1 - Hochhaus, Andreas A1 - Ernst, Thomas A1 - Hoffmann, Carsten A1 - Zernecke, Alma A1 - Frietsch, Jochen J. T1 - Phosphorylation-dependent differences in CXCR4-LASP1-AKT1 interaction between breast cancer and chronic myeloid leukemia JF - Cells N2 - The serine/threonine protein kinase AKT1 is a downstream target of the chemokine receptor 4 (CXCR4), and both proteins play a central role in the modulation of diverse cellular processes, including proliferation and cell survival. While in chronic myeloid leukemia (CML) the CXCR4 is downregulated, thereby promoting the mobilization of progenitor cells into blood, the receptor is highly expressed in breast cancer cells, favoring the migratory capacity of these cells. Recently, the LIM and SH3 domain protein 1 (LASP1) has been described as a novel CXCR4 binding partner and as a promoter of the PI3K/AKT pathway. In this study, we uncovered a direct binding of LASP1, phosphorylated at S146, to both CXCR4 and AKT1, as shown by immunoprecipitation assays, pull-down experiments, and immunohistochemistry data. In contrast, phosphorylation of LASP1 at Y171 abrogated these interactions, suggesting that both LASP1 phospho-forms interact. Finally, findings demonstrating different phosphorylation patterns of LASP1 in breast cancer and chronic myeloid leukemia may have implications for CXCR4 function and tyrosine kinase inhibitor treatment. KW - LASP1 KW - CXCR4 KW - AKT1 KW - CML KW - breast cancer Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-200638 SN - 2073-4409 VL - 9 IS - 2 ER - TY - JOUR A1 - Proetel, Ulrike A1 - Pletsch, Nadine A1 - Lauseker, Michael A1 - Müller, Martin C. A1 - Hanfstein, Benjamin A1 - Krause, Stefan W. A1 - Kalmanti, Lida A1 - Schreiber, Annette A1 - Heim, Dominik A1 - Baerlocher, Gabriela M. A1 - Hofmann, Wolf-Karsten A1 - Lange, Elisabeth A1 - Einsele, Hermann A1 - Wernli, Martin A1 - Kremers, Stephan A1 - Schlag, Rudolf A1 - Müller, Lothar A1 - Hänel, Mathias A1 - Link, Hartmut A1 - Hertenstein, Bernd A1 - Pfirrmann, Markus A1 - Hochhaus, Andreas A1 - Hasford, Joerg A1 - Hehlmann, Rüdiger A1 - Saußele, Susanne T1 - Older patients with chronic myeloid leukemia (≥65 years) profit more from higher imatinib doses than younger patients: a subanalysis of the randomized CML-Study IV JF - Annals of Hematology N2 - The impact of imatinib dose on response rates and survival in older patients with chronic myeloid leukemia in chronic phase has not been studied well. We analyzed data from the German CML-Study IV, a randomized five-arm treatment optimization study in newly diagnosed BCR-ABL-positive chronic myeloid leukemia in chronic phase. Patients randomized to imatinib 400 mg/day (IM400) or imatinib 800 mg/day (IM800) and stratified according to age (≥65 years vs. <65 years) were compared regarding dose, response, adverse events, rates of progression, and survival. The full 800 mg dose was given after a 6-week run-in period with imatinib 400 mg/day. The dose could then be reduced according to tolerability. A total of 828 patients were randomized to IM400 or IM800. Seven hundred eighty-four patients were evaluable (IM400, 382; IM800, 402). One hundred ten patients (29 %) on IM400 and 83 (21 %) on IM800 were ≥65 years. The median dose per day was lower for patients ≥65 years on IM800, with the highest median dose in the first year (466 mg/day for patients ≥65 years vs. 630 mg/day for patients <65 years). Older patients on IM800 achieved major molecular remission and deep molecular remission as fast as younger patients, in contrast to standard dose imatinib with which older patients achieved remissions much later than younger patients. Grades 3 and 4 adverse events were similar in both age groups. Five-year relative survival for older patients was comparable to that of younger patients. We suggest that the optimal dose for older patients is higher than 400 mg/day. ClinicalTrials.gov identifier: NCT00055874 KW - chronic myeloid leukemia KW - older patients KW - different imatinib dose regimens KW - early applied higher imatinib dosages Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-121574 SN - 0939-5555 VL - 93 IS - 7 ER - TY - JOUR A1 - Eckardt, Jan-Niklas A1 - Stasik, Sebastian A1 - Kramer, Michael A1 - Röllig, Christoph A1 - Krämer, Alwin A1 - Scholl, Sebastian A1 - Hochhaus, Andreas A1 - Crysandt, Martina A1 - Brümmendorf, Tim H. A1 - Naumann, Ralph A1 - Steffen, Björn A1 - Kunzmann, Volker A1 - Einsele, Hermann A1 - Schaich, Markus A1 - Burchert, Andreas A1 - Neubauer, Andreas A1 - Schäfer-Eckart, Kerstin A1 - Schliemann, Christoph A1 - Krause, Stefan W. A1 - Herbst, Regina A1 - Hänel, Mathias A1 - Frickhofen, Norbert A1 - Noppeney, Richard A1 - Kaiser, Ulrich A1 - Baldus, Claudia D. A1 - Kaufmann, Martin A1 - Rácil, Zdenek A1 - Platzbecker, Uwe A1 - Berdel, Wolfgang E. A1 - Mayer, Jiří A1 - Serve, Hubert A1 - Müller-Tidow, Carsten A1 - Ehninger, Gerhard A1 - Stölzel, Friedrich A1 - Kroschinsky, Frank A1 - Schetelig, Johannes A1 - Bornhäuser, Martin A1 - Thiede, Christian A1 - Middeke, Jan Moritz T1 - Loss-of-function mutations of BCOR are an independent marker of adverse outcomes in intensively treated patients with acute myeloid leukemia JF - Cancers N2 - Acute myeloid leukemia (AML) is characterized by recurrent genetic events. The BCL6 corepressor (BCOR) and its homolog, the BCL6 corepressor-like 1 (BCORL1), have been reported to be rare but recurrent mutations in AML. Previously, smaller studies have reported conflicting results regarding impacts on outcomes. Here, we retrospectively analyzed a large cohort of 1529 patients with newly diagnosed and intensively treated AML. BCOR and BCORL1 mutations were found in 71 (4.6%) and 53 patients (3.5%), respectively. Frequently co-mutated genes were DNTM3A, TET2 and RUNX1. Mutated BCORL1 and loss-of-function mutations of BCOR were significantly more common in the ELN2017 intermediate-risk group. Patients harboring loss-of-function mutations of BCOR had a significantly reduced median event-free survival (HR = 1.464 (95%-Confidence Interval (CI): 1.005–2.134), p = 0.047), relapse-free survival (HR = 1.904 (95%-CI: 1.163–3.117), p = 0.01), and trend for reduced overall survival (HR = 1.495 (95%-CI: 0.990–2.258), p = 0.056) in multivariable analysis. Our study establishes a novel role for loss-of-function mutations of BCOR regarding risk stratification in AML, which may influence treatment allocation. KW - acute myeloid leukemia KW - BCOR KW - BCORL1 KW - loss-of-function KW - risk stratification KW - survival Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-236735 SN - 2072-6694 VL - 13 IS - 9 ER - TY - JOUR A1 - Frietsch, Jochen J. A1 - Kastner, Carolin A1 - Grunewald, Thomas G.P. A1 - Schweigel, Hardy A1 - Nollau, Peter A1 - Ziermann, Janine A1 - Clement, Joachim H. A1 - La Resée, Paul A1 - Hochhaus, Andreas A1 - Butt, Elke T1 - LASP1 is a novel BCR-ABL substrate and a phosphorylation-dependent binding partner of CRKL in chronic myeloid leukemia JF - Oncotarget N2 - Chronic myeloid leukemia (CML) is characterized by a genomic translocation generating a permanently active BCR-ABL oncogene with a complex pattern of atypically tyrosine-phosphorylated proteins that drive the malignant phenotype of CML. Recently, the LIM and SH3 domain protein 1 (LASP1) was identified as a component of a six gene signature that is strongly predictive for disease progression and relapse in CML patients. However, the underlying mechanisms why LASP1 expression correlates with dismal outcome remained unresolved. Here, we identified LASP1 as a novel and overexpressed direct substrate of BCR-ABL in CML. We demonstrate that LASP1 is specifically phosphorylated by BCR-ABL at tyrosine-171 in CML patients, which is abolished by tyrosine kinase inhibitor therapy. Further studies revealed that LASP1 phosphorylation results in an association with CRKL - another specific BCR-ABL substrate and bona fide biomarker for BCR-ABL activity. pLASP1-Y171 binds to non-phosphorylated CRKL at its SH2 domain. Accordingly, the BCR-ABL-mediated pathophysiological hyper-phosphorylation of LASP1 in CML disrupts normal regulation of CRKL and LASP1, which likely has implications on downstream BCR-ABL signaling. Collectively, our results suggest that LASP1 phosphorylation might serve as an additional candidate biomarker for assessment of BCR-ABL activity and provide a first step toward a molecular understanding of LASP1 function in CML. KW - CRKL KW - nilotinib KW - BCR-ABL KW - CML KW - LASP1 Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-120639 SN - 1949-2553 VL - 5 IS - 14 ER - TY - JOUR A1 - Herrmann, Andreas B. A1 - Müller, Martha‐Lena A1 - Orth, Martin F. A1 - Müller, Jörg P. A1 - Zernecke, Alma A1 - Hochhaus, Andreas A1 - Ernst, Thomas A1 - Butt, Elke A1 - Frietsch, Jochen J. T1 - Knockout of LASP1 in CXCR4 expressing CML cells promotes cell persistence, proliferation and TKI resistance JF - Journal of Cellular and Molecular Medicine N2 - Chronic myeloid leukaemia (CML) is a clonal myeloproliferative stem cell disorder characterized by the constitutively active BCR‐ABL tyrosine kinase. The LIM and SH3 domain protein 1 (LASP1) has recently been identified as a novel BCR‐ABL substrate and is associated with proliferation, migration, tumorigenesis and chemoresistance in several cancers. Furthermore, LASP1 was shown to bind to the chemokine receptor 4 (CXCR4), thought to be involved in mechanisms of relapse. In order to identify potential LASP1‐mediated pathways and related factors that may help to further eradicate minimal residual disease (MRD), the effect of LASP1 on processes involved in progression and maintenance of CML was investigated. The present data indicate that not only overexpression of CXCR4, but also knockout of LASP1 contributes to proliferation, reduced apoptosis and migration as well as increased adhesive potential of K562 CML cells. Furthermore, LASP1 depletion in K562 CML cells leads to decreased cytokine release and reduced NK cell‐mediated cytotoxicity towards CML cells. Taken together, these results indicate that in CML, reduced levels of LASP1 alone and in combination with high CXCR4 expression may contribute to TKI resistance. KW - BCR‐ABL KW - CML KW - CXCR4 KW - LASP1 KW - nilotinib KW - precursor cells Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-214122 VL - 24 IS - 5 SP - 2942 EP - 2955 ER - TY - JOUR A1 - Hanfstein, Benjamin A1 - Lauseker, Michael A1 - Hehlmann, Rüdiger A1 - Saussele, Susanne A1 - Erben, Philipp A1 - Dietz, Christian A1 - Fabarius, Alice A1 - Proetel, Ulrike A1 - Schnittger, Susanne A1 - Haferlach, Claudia A1 - Krause, Stefan W. A1 - Schubert, Jörg A1 - Einsele, Hermann A1 - Hänel, Mathias A1 - Dengler, Jolanta A1 - Falge, Christiane A1 - Kanz, Lothar A1 - Neubauer, Andreas A1 - Kneba, Michael A1 - Stengelmann, Frank A1 - Pfreundschuh, Michael A1 - Waller, Cornelius F. A1 - Spiekerman, Karsten A1 - Baerlocher, Gabriela M. A1 - Pfirrmann, Markus A1 - Hasford, Joerg A1 - Hofmann, Wolf-Karsten A1 - Hochhaus, Andreas A1 - Müller, Martin C. T1 - Distinct characteristics of e13a2 versus e14a2 BCR-ABL1 driven chronic myeloid leukemia under first-line therapy with imatinib JF - Haematologica N2 - The vast majority of chronic myeloid leukemia patients express a BCR-ABL1 fusion gene mRNA encoding a 210 kDa tyrosine kinase which promotes leukemic transformation. A possible differential impact of the corresponding BCR-ABL1 transcript variants e13a2 ("b2a2") and e14a2 ("b3a2") on disease phenotype and outcome is still a subject of debate. A total of 1105 newly diagnosed imatinib-treated patients were analyzed according to transcript type at diagnosis (e13a2, n=451; e14a2, n=496; e13a2+e14a2, n=158). No differences regarding age, sex, or Euro risk score were observed. A significant difference was found between e13a2 and e14a2 when comparing white blood cells (88 vs. 65 x 10(9)/L, respectively; P<0.001) and platelets (296 vs. 430 x 109/L, respectively; P<0.001) at diagnosis, indicating a distinct disease phenotype. No significant difference was observed regarding other hematologic features, including spleen size and hematologic adverse events, during imatinib-based therapies. Cumulative molecular response was inferior in e13a2 patients (P=0.002 for major molecular response; P<0.001 for MR4). No difference was observed with regard to cytogenetic response and overall survival. In conclusion, e13a2 and e14a2 chronic myeloid leukemia seem to represent distinct biological entities. However, clinical outcome under imatinib treatment was comparable and no risk prediction can be made according to e13a2 versus e14a2 BCR-ABL1 transcript type at diagnosis. (clinicaltrials.gov identifier: 00055874) KW - chronic myelogenous leukemia KW - polymerase-chain-reaktion KW - hybrid messenger RNA KW - chronic phase KW - cytogenetic response KW - no correlation KW - ABL gene KW - transcripts KW - breakpoint KW - survival Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-115476 SN - 1592-8721 VL - 99 IS - 9 ER - TY - JOUR A1 - Saussele, Susanne A1 - Hehlmann, Ruediger A1 - Fabarius, Alice A1 - Jeromin, Sabine A1 - Proetel, Ulrike A1 - Rinaldetti, Sebastien A1 - Kohlbrenner, Katharina A1 - Einsele, Hermann A1 - Falge, Christine A1 - Kanz, Lothar A1 - Neubauer, Andreas A1 - Kneba, Michael A1 - Stegelmann, Frank A1 - Pfreundschuh, Michael A1 - Waller, Cornelius F. A1 - Oppliger Leibundgut, Elisabeth A1 - Heim, Dominik A1 - Krause, Stefan W. A1 - Hofmann, Wolf-Karsten A1 - Hasford, Joerg A1 - Pfirrmann, Markus A1 - Müller, Martin C. A1 - Hochhaus, Andreas A1 - Lauseker, Michael T1 - Defining therapy goals for major molecular remission in chronic myeloid leukemia: results of the randomized CML Study IV JF - Leukemia N2 - Major molecular remission (MMR) is an important therapy goal in chronic myeloid leukemia (CML). So far, MMR is not a failure criterion according to ELN management recommendation leading to uncertainties when to change therapy in CML patients not reaching MMR after 12 months. At monthly landmarks, for different molecular remission status Hazard ratios (HR) were estimated for patients registered to CML study IV who were divided in a learning and a validation sample. The minimum HR for MMR was found at 2.5 years with 0.28 (compared to patients without remission). In the validation sample, a significant advantage for progression-free survival (PFS) for patients in MMR could be detected (p-value 0.007). The optimal time to predict PFS in patients with MMR could be validated in an independent sample at 2.5 years. With our model we provide a suggestion when to define lack of MMR as therapy failure and thus treatment change should be considered. The optimal response time for 1% BCR-ABL at about 12-15 months was confirmed and for deep molecular remission no specific time point was detected. Nevertheless, it was demonstrated that the earlier the MMR is achieved the higher is the chance to attain deep molecular response later. KW - Chronic myeloid leukaemia KW - Molecularly targeted therapy KW - Risk factors KW - Risk factors KW - Translational research Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-227528 VL - 32 IS - 5 ER -