10 results on '"Tamara Rothenburger"'
Search Results
2. Identification of novel antiviral drug candidates using an optimized SARS-CoV-2 phenotypic screening platform
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Denisa Bojkova, Philipp Reus, Leona Panosch, Marco Bechtel, Tamara Rothenburger, Joshua D. Kandler, Annika Pfeiffer, Julian U.G. Wagner, Mariana Shumliakivska, Stefanie Dimmeler, Ruth Olmer, Ulrich Martin, Florian W.R. Vondran, Tuna Toptan, Florian Rothweiler, Richard Zehner, Holger F. Rabenau, Karen L. Osman, Steven T. Pullan, Miles W. Carroll, Richard Stack, Sandra Ciesek, Mark N. Wass, Martin Michaelis, and Jindrich Cinatl, Jr.
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Virology ,Drugs ,Screening in health technology ,Science - Abstract
Summary: Reliable, easy-to-handle phenotypic screening platforms are needed for the identification of anti-SARS-CoV-2 compounds. Here, we present caspase 3/7 activity as a readout for monitoring the replication of SARS-CoV-2 isolates from different variants, including a remdesivir-resistant strain, and of other coronaviruses in numerous cell culture models, independently of cytopathogenic effect formation. Compared to other models, the Caco-2 subline Caco-2-F03 displayed superior performance. It possesses a stable SARS-CoV-2 susceptibility phenotype and does not produce false-positive hits due to drug-induced phospholipidosis. A proof-of-concept screen of 1,796 kinase inhibitors identified known and novel antiviral drug candidates including inhibitors of phosphoglycerate dehydrogenase (PHGDH), CDC like kinase 1 (CLK-1), and colony stimulating factor 1 receptor (CSF1R). The activity of the PHGDH inhibitor NCT-503 was further increased in combination with the hexokinase II (HK2) inhibitor 2-deoxy-D-glucose, which is in clinical development for COVID-19. In conclusion, caspase 3/7 activity detection in SARS-CoV-2-infected Caco-2-F03 cells provides a simple phenotypic high-throughput screening platform for SARS-CoV-2 drug candidates that reduces false-positive hits.
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- 2023
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3. Differences between intrinsic and acquired nucleoside analogue resistance in acute myeloid leukaemia cells
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Tamara Rothenburger, Dominique Thomas, Yannick Schreiber, Paul R. Wratil, Tamara Pflantz, Kirsten Knecht, Katie Digianantonio, Joshua Temple, Constanze Schneider, Hanna-Mari Baldauf, Katie-May McLaughlin, Florian Rothweiler, Berna Bilen, Samira Farmand, Denisa Bojkova, Rui Costa, Nerea Ferreirós, Gerd Geisslinger, Thomas Oellerich, Yong Xiong, Oliver T. Keppler, Mark N. Wass, Martin Michaelis, and Jindrich Cinatl
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Leukemia ,Acute myeloid leukemia ,Acute lymphoblastic leukemia ,CNDAC ,Sapacitabine ,SAMHD1 ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Abstract Background SAMHD1 mediates resistance to anti-cancer nucleoside analogues, including cytarabine, decitabine, and nelarabine that are commonly used for the treatment of leukaemia, through cleavage of their triphosphorylated forms. Hence, SAMHD1 inhibitors are promising candidates for the sensitisation of leukaemia cells to nucleoside analogue-based therapy. Here, we investigated the effects of the cytosine analogue CNDAC, which has been proposed to be a SAMHD1 inhibitor, in the context of SAMHD1. Methods CNDAC was tested in 13 acute myeloid leukaemia (AML) cell lines, in 26 acute lymphoblastic leukaemia (ALL) cell lines, ten AML sublines adapted to various antileukaemic drugs, 24 single cell-derived clonal AML sublines, and primary leukaemic blasts from 24 AML patients. Moreover, 24 CNDAC-resistant sublines of the AML cell lines HL-60 and PL-21 were established. The SAMHD1 gene was disrupted using CRISPR/Cas9 and SAMHD1 depleted using RNAi, and the viral Vpx protein. Forced DCK expression was achieved by lentiviral transduction. SAMHD1 promoter methylation was determined by PCR after treatment of genomic DNA with the methylation-sensitive HpaII endonuclease. Nucleoside (analogue) triphosphate levels were determined by LC-MS/MS. CNDAC interaction with SAMHD1 was analysed by an enzymatic assay and by crystallisation. Results Although the cytosine analogue CNDAC was anticipated to inhibit SAMHD1, SAMHD1 mediated intrinsic CNDAC resistance in leukaemia cells. Accordingly, SAMHD1 depletion increased CNDAC triphosphate (CNDAC-TP) levels and CNDAC toxicity. Enzymatic assays and crystallisation studies confirmed CNDAC-TP to be a SAMHD1 substrate. In 24 CNDAC-adapted acute myeloid leukaemia (AML) sublines, resistance was driven by DCK (catalyses initial nucleoside phosphorylation) loss. CNDAC-adapted sublines displayed cross-resistance only to other DCK substrates (e.g. cytarabine, decitabine). Cell lines adapted to drugs not affected by DCK or SAMHD1 remained CNDAC sensitive. In cytarabine-adapted AML cells, increased SAMHD1 and reduced DCK levels contributed to cytarabine and CNDAC resistance. Conclusion Intrinsic and acquired resistance to CNDAC and related nucleoside analogues are driven by different mechanisms. The lack of cross-resistance between SAMHD1/ DCK substrates and non-substrates provides scope for next-line therapies after treatment failure.
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- 2021
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4. Selective inactivation of hypomethylating agents by SAMHD1 provides a rationale for therapeutic stratification in AML
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Thomas Oellerich, Constanze Schneider, Dominique Thomas, Kirsten M. Knecht, Olga Buzovetsky, Lars Kaderali, Christoph Schliemann, Hanibal Bohnenberger, Linus Angenendt, Wolfgang Hartmann, Eva Wardelmann, Tamara Rothenburger, Sebastian Mohr, Sebastian Scheich, Federico Comoglio, Anne Wilke, Philipp Ströbel, Hubert Serve, Martin Michaelis, Nerea Ferreirós, Gerd Geisslinger, Yong Xiong, Oliver T. Keppler, and Jindrich Cinatl
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Science - Abstract
In acute myeloid leukemia, hypomethylating agents decitabine and azacytidine are used interchangeably. Here, the authors show that the major metabolite of decitabine, but not azacytidine, is subject to SAMHD1 inactivation, highlighting SAMHD1 as a potential biomarker and therapeutic target
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- 2019
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5. Long-term cultivation using ineffective MDM2 inhibitor concentrations alters the drug sensitivity profiles of PL21 leukaemia cells
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Martin Michaelis, Florian Rothweiler, Constanze Schneider, Tamara Rothenburger, Marco Mernberger, Andrea Nist, Thorsten Stiewe, Jindrich Cinatl, and Michael Nevels
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Cancer ,Drug response ,Leukemia ,Resistance ,Therapy ,Technology ,Medicine ,Science - Abstract
Acquired MDM2 inhibitor resistance is commonly caused by loss-of-function TP53 mutations. In addition to the selection of TP53-mutant cells by MDM2 inhibitors, MDM2 inhibitor-induced DNA damage may promote the formation of TP53 mutations. Here, we cultivated 12 sublines of the intrinsically MDM2 inhibitor-resistant TP53 wild-type acute myeloid leukaemia cell line PL21 for 52 passages in the presence of ineffective concentrations of the MDM2 inhibitor nutlin-3 but did not observe loss-of-function TP53 mutations. This suggests that MDM2 inhibitors select TP53-mutant cells after mutations have occurred, but do not directly promote TP53 mutations. Unexpectedly, many sublines displayed increased sensitivity to the anti-cancer drugs cytarabine, doxorubicin, or gemcitabine. Consequently, therapies can affect the outcome of next-line treatments, even in the absence of a therapy response. This finding is conceptually novel. A better understanding of such processes will inform the design of improved therapy protocols in the future.
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- 2020
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6. Repurposing of the antibiotic nitroxoline for the treatment of mpox
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Denisa Bojkova, Nadja Zöller, Manuela Tietgen, Katja Steinhorst, Marco Bechtel, Tamara Rothenburger, Joshua D. Kandler, Julia Schneider, Victor M. Corman, Sandra Ciesek, Holger F. Rabenau, Mark N. Wass, Stefan Kippenberger, Stephan Göttig, Martin Michaelis, and Jindrich Cinatl
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Infectious Diseases ,Virology - Abstract
The antiviral drugs tecovirimat, brincidofovir, and cidofovir are considered for mpox (monkeypox) treatment despite a lack of clinical evidence. Moreover, their use is affected by toxic side-effects (brincidofovir, cidofovir), limited availability (tecovirimat), and potentially by resistance formation. Hence, additional, readily available drugs are needed. Here, therapeutic concentrations of nitroxoline, a hydroxyquinoline antibiotic with a favourable safety profile in humans, inhibited the replication of 12 mpox virus isolates from the current outbreak in primary cultures of human keratinocytes and fibroblasts and a skin explant model by interference with host cell signalling. Tecovirimat, but not nitroxoline, treatment resulted in rapid resistance development. Nitroxoline remained effective against the tecovirimat-resistant strain and increased the anti-mpox virus activity of tecovirimat and brincidofovir. Moreover, nitroxoline inhibited bacterial and viral pathogens that are often co-transmitted with mpox. In conclusion, nitroxoline is a repurposing candidate for the treatment of mpox due to both antiviral and antimicrobial activity.
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- 2022
7. SAMHD1 is a key regulator of the lineage-specific response of acute lymphoblastic leukaemias to nelarabine
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Tamara Rothenburger, Jindrich Cinatl, Tobias Herold, Andrew Feber, Katie-May McLaughlin, Florian Rothweiler, Tim R. Fenton, Martin Michaelis, Mark N. Wass, Constanze Schneider, Oliver T. Keppler, and Thomas Oellerich
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0301 basic medicine ,RM ,Medicine (miscellaneous) ,Antineoplastic Agents ,Precursor T-Cell Lymphoblastic Leukemia-Lymphoma ,General Biochemistry, Genetics and Molecular Biology ,Article ,Transcriptome ,SAM Domain and HD Domain-Containing Protein 1 ,03 medical and health sciences ,0302 clinical medicine ,Cell Line, Tumor ,Precursor B-Cell Lymphoblastic Leukemia-Lymphoma ,hemic and lymphatic diseases ,medicine ,Biomarkers, Tumor ,Humans ,Chemotherapy ,ddc:610 ,Promoter Regions, Genetic ,lcsh:QH301-705.5 ,Acute lymphocytic leukaemia ,Nucleoside analogue ,Chemistry ,Gene Expression Regulation, Leukemic ,Prodrug ,DNA Methylation ,030104 developmental biology ,lcsh:Biology (General) ,Cell culture ,Drug Resistance, Neoplasm ,030220 oncology & carcinogenesis ,DNA methylation ,Nelarabine ,Cytarabine ,Cancer research ,Arabinonucleosides ,General Agricultural and Biological Sciences ,Nucleoside ,medicine.drug ,SAMHD1 - Abstract
The nucleoside analogue nelarabine, the prodrug of arabinosylguanine (AraG), is effective against T-cell acute lymphoblastic leukaemia (T-ALL) but not against B-cell ALL (B-ALL). The underlying mechanisms have remained elusive. Here, data from pharmacogenomics studies and a panel of ALL cell lines reveal an inverse correlation between nelarabine sensitivity and the expression of SAMHD1, which can hydrolyse and inactivate triphosphorylated nucleoside analogues. Lower SAMHD1 abundance is detected in T-ALL than in B-ALL in cell lines and patient-derived leukaemic blasts. Mechanistically, T-ALL cells display increased SAMHD1 promoter methylation without increased global DNA methylation. SAMHD1 depletion sensitises B-ALL cells to AraG, while ectopic SAMHD1 expression in SAMHD1-null T-ALL cells induces AraG resistance. SAMHD1 has a larger impact on nelarabine/AraG than on cytarabine in ALL cells. Opposite effects are observed in acute myeloid leukaemia cells, indicating entity-specific differences. In conclusion, SAMHD1 promoter methylation and, in turn, SAMHD1 expression levels determine ALL cell response to nelarabine., Rothenburger et al. combine the analysis of data from large pharmacogenomics screens with cell line experiments to elucidate mechanisms behind nelarabine resistance in acute lymphoblastic leukaemia (ALL). They identify low expression of the dNTP hydrolase SAMHD1 as a determinant of nelarabine sensitivity, suggesting the enzyme as a biomarker.
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- 2020
8. Differences between intrinsic and acquired nucleoside analogue resistance in acute myeloid leukaemia cells
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Oliver T. Keppler, Gerd Geisslinger, Denisa Bojkova, Tamara Rothenburger, Tamara Pflantz, Hanna-Mari Baldauf, Yong Xiong, Florian Rothweiler, Martin Michaelis, Thomas Oellerich, Paul R. Wratil, Berna Bilen, Mark N. Wass, Rui Costa, Constanze Schneider, Nerea Ferreirós, Dominique Thomas, Yannick Schreiber, Samira Farmand, Katie Digianantonio, Kirsten M. Knecht, Joshua Temple, Jindrich Cinatl, and Katie-May McLaughlin
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chemistry.chemical_compound ,chemistry ,Nucleoside analogue ,Nelarabine ,medicine ,Cytarabine ,Cancer research ,Decitabine ,Context (language use) ,Nucleoside ,Cytosine ,medicine.drug ,SAMHD1 - Abstract
SummaryBackgroundSAMHD1 mediates resistance to anti-cancer nucleoside analogues, including cytarabine, decitabine, and nelarabine that are commonly used for the treatment of leukaemia, through cleavage of their triphosphorylated forms. Hence, SAMHD1 inhibitors are promising candidates for the sensitisation of leukaemia cells to nucleoside analogue-based therapy. Here, we investigated the effects of the cytosine analogue CNDAC, which has been proposed to be a SAMHD1 substrate, in the context of SAMHD1.MethodsCNDAC was tested in 13 acute myeloid leukaemia (AML cell lines), in 26 acute lymphoblastic leukaemia cell lines, ten AML sublines adapted to various antileukaemic drugs, 24 single cell-derived clonal AML sublines, and primary leukaemic blasts from 24 AML patients. Moreover, 24 CNDAC-resistant sublines of the AML cell lines HL-60 and PL-21 were established. The SAMHD1 gene was disrupted using CRISPR/Cas9 and SAMHD1 depleted using RNAi, and the viral Vpx protein. Forced DCK expression was achieved by lentiviral transduction. SAMHD1 promoter methylation was determined by PCR after treatment of genomic DNA with the methylation-sensitive HpaII endonuclease. Nucleoside (analogue) triphosphate levels were determined by LC-MS/MS. CNDAC interaction with SAMHD1 was analysed by an enzymatic assay and by crystallisation.ResultsAlthough the cytosine analogue CNDAC was anticipated to inhibit SAMHD1, SAMHD1 mediated intrinsic CNDAC resistance in leukaemia cells. Accordingly, SAMHD1 depletion increased CNDAC triphosphate (CNDAC-TP) levels and CNDAC toxicity. Enzymatic assays and crystallisation studies confirmed CNDAC-TP to be a SAMHD1 substrate. In 24 CNDAC-adapted acute myeloid leukaemia (AML) sublines, resistance was driven by DCK (catalyses initial nucleoside phosphorylation) loss. CNDAC-adapted sublines displayed cross-resistance only to other DCK substrates (e.g. cytarabine, decitabine). Cell lines adapted to drugs not affected by DCK or SAMHD1 remained CNDAC sensitive. In cytarabine-adapted AML cells, increased SAMHD1 and reduced DCK levels contributed to cytarabine and CNDAC resistance.ConclusionIntrinsic and acquired resistance to CNDAC and related nucleoside analogues are driven by different mechanisms. The lack of cross-resistance between SAMHD1/ DCK substrates and non-substrates provides scope for next-line therapies after treatment failure.
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- 2021
9. Selective inactivation of hypomethylating agents by SAMHD1 provides a rationale for therapeutic stratification in AML
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Olga Buzovetsky, Sebastian Scheich, Eva Wardelmann, Jindrich Cinatl, Sebastian Mohr, Martin Michaelis, Constanze Schneider, Wolfgang Hartmann, Yong Xiong, Thomas Oellerich, Kirsten M. Knecht, Hanibal Bohnenberger, Gerd Geisslinger, Federico Comoglio, Philipp Ströbel, Tamara Rothenburger, Oliver T. Keppler, Lars Kaderali, Christoph Schliemann, Dominique Thomas, Nerea Ferreirós, Anne C. Wilke, Hubert Serve, Linus Angenendt, Publica, Knecht, Kirsten M [0000-0001-5892-3770], Bohnenberger, Hanibal [0000-0003-1038-1030], Angenendt, Linus [0000-0003-2502-9910], Hartmann, Wolfgang [0000-0002-7609-5021], Wardelmann, Eva [0000-0001-6788-4910], Scheich, Sebastian [0000-0001-6408-3536], Comoglio, Federico [0000-0002-8970-6610], Serve, Hubert [0000-0001-8472-5516], Michaelis, Martin [0000-0002-5710-5888], Cinatl, Jindrich [0000-0002-6744-2087], and Apollo - University of Cambridge Repository
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0301 basic medicine ,Myeloid ,General Physics and Astronomy ,02 engineering and technology ,Mice ,Bone Marrow ,hemic and lymphatic diseases ,lcsh:Science ,Cancer ,Multidisciplinary ,hypomethylating agents ,Gene Expression Regulation, Leukemic ,Myeloid leukemia ,021001 nanoscience & nanotechnology ,3. Good health ,Leukemia ,Leukemia, Myeloid, Acute ,medicine.anatomical_structure ,Treatment Outcome ,Oncology ,Azacitidine ,Biomarker (medicine) ,Female ,0210 nano-technology ,medicine.drug ,RM ,Antimetabolites, Antineoplastic ,Science ,Primary Cell Culture ,Decitabine ,General Biochemistry, Genetics and Molecular Biology ,Article ,SAM Domain and HD Domain-Containing Protein 1 ,03 medical and health sciences ,Cell Line, Tumor ,medicine ,Biomarkers, Tumor ,Animals ,Humans ,ddc:610 ,Retrospective Studies ,business.industry ,Patient Selection ,General Chemistry ,DNA Methylation ,medicine.disease ,Xenograft Model Antitumor Assays ,030104 developmental biology ,Drug Resistance, Neoplasm ,Cancer research ,lcsh:Q ,Bone marrow ,business ,Biomarkers ,SAMHD1 - Abstract
Hypomethylating agents decitabine and azacytidine are regarded as interchangeable in the treatment of acute myeloid leukemia (AML). However, their mechanisms of action remain incompletely understood, and predictive biomarkers for HMA efficacy are lacking. Here, we show that the bioactive metabolite decitabine triphosphate, but not azacytidine triphosphate, functions as activator and substrate of the triphosphohydrolase SAMHD1 and is subject to SAMHD1-mediated inactivation. Retrospective immunohistochemical analysis of bone marrow specimens from AML patients at diagnosis revealed that SAMHD1 expression in leukemic cells inversely correlates with clinical response to decitabine, but not to azacytidine. SAMHD1 ablation increases the antileukemic activity of decitabine in AML cell lines, primary leukemic blasts, and xenograft models. AML cells acquire resistance to decitabine partly by SAMHD1 up-regulation. Together, our data suggest that SAMHD1 is a biomarker for the stratified use of hypomethylating agents in AML patients and a potential target for the treatment of decitabine-resistant leukemia., In acute myeloid leukemia, hypomethylating agents decitabine and azacytidine are used interchangeably. Here, the authors show that the major metabolite of decitabine, but not azacytidine, is subject to SAMHD1 inactivation, highlighting SAMHD1 as a potential biomarker and therapeutic target
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- 2019
10. TP53 mutations and drug sensitivity in acute myeloid leukaemia cells with acquired MDM2 inhibitor resistance
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Florian Rothweiler, Thorsten Stiewe, Tamara Rothenburger, J. Cinatl, Deimling Av, Marco Mernberger, Daniel Speidel, Constanze Schneider, Martin Michaelis, and Andrea Nist
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education.field_of_study ,Chemotherapy ,Mutation ,medicine.medical_treatment ,Population ,Biology ,medicine.disease_cause ,Fludarabine ,Cancer cell ,Cancer research ,Cytarabine ,medicine ,Cytotoxic T cell ,education ,neoplasms ,Etoposide ,medicine.drug - Abstract
Background:MDM2 inhibitors are under investigation for the treatment of acute myeloid leukaemia (AML) patients in phase III clinical trials. To study resistance formation to MDM2 inhibitors in AML cells, we here established 45 sub-lines of the AMLTP53wild-type cell lines MV4-11 (15 sub-lines), OCI-AML-2 (10 sub-lines), OCI-AML-3 (12 sub-lines), and SIG-M5 (8 sub-lines) with resistance to the MDM2 inhibitor nutlin-3.Methods: Nutlin-3-resistant sub-lines were established by continuous exposure to stepwise increasing drug concentrations. TheTP53status was determined by next generation sequencing, cell viability was measured by MTT assay, and p53 was depleted using lentiviral vectors encoding shRNA.Results:All MV4-11 sub-lines harboured the same R248W mutation and all OCI-AML-2 sub-lines the same Y220C mutation, indicating the selection of pre-existingTP53-mutant subpopulations. In concordance, rare alleles harbouring the respective mutations could be detected in the parental MV4-11 and OCI-AML-2 cell lines. The OCI-AML-3 and SIG-M5 sub-lines were characterised by varyingTP53mutations or wild typeTP53, indicating the induction ofde novo TP53mutations. Doxorubicin, etoposide, gemcitabine, cytarabine, and fludarabine resistance profiles revealed a noticeable heterogeneity among the sub-lines even of the same parental cell lines. Loss-of-p53 function was not generally associated with decreased sensitivity to cytotoxic drugs.Conclusion:We introduce a substantial set of models of acquired MDM2 inhibitor resistance in AML. MDM2 inhibitors select, in dependence on the nature of a given AML cell population, pre-existingTP53-mutant subpopulations or inducede novo TP53mutations. Although loss-of-p53 function has been associated with chemoresistance in AML, nutlin-3-adapted sub-lines displayed in the majority of experiments similar or increased drug sensitivity compared to the respective parental cells. Hence, chemotherapy may remain an option for AML patients after MDM2 inhibitor therapy failure. Even sub-lines of the same parental cancer cell line displayed considerable heterogeneity in their response to other anti-cancer drugs, indicating the need for the detailed understanding and monitoring of the evolutionary processes in cancer cell populations in response to therapy as part of future individualised treatment protocols.
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- 2018
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