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  • American Association for Cancer Research (AACR)  (20)
  • Valent, Peter  (20)
  • 1
    In: Cancer Discovery, American Association for Cancer Research (AACR), Vol. 12, No. 2 ( 2022-02-01), p. 372-387
    Kurzfassung: Personalized medicine aims to match the right drug with the right patient by using specific features of the individual patient's tumor. However, current strategies of personalized therapy matching provide treatment opportunities for less than 10% of patients with cancer. A promising method may be drug profiling of patient biopsy specimens with single-cell resolution to directly quantify drug effects. We prospectively tested an image-based single-cell functional precision medicine (scFPM) approach to guide treatments in 143 patients with advanced aggressive hematologic cancers. Fifty-six patients (39%) were treated according to scFPM results. At a median follow-up of 23.9 months, 30 patients (54%) demonstrated a clinical benefit of more than 1.3-fold enhanced progression-free survival compared with their previous therapy. Twelve patients (40% of responders) experienced exceptional responses lasting three times longer than expected for their respective disease. We conclude that therapy matching by scFPM is clinically feasible and effective in advanced aggressive hematologic cancers. Significance: This is the first precision medicine trial using a functional assay to instruct n-of-one therapies in oncology. It illustrates that for patients lacking standard therapies, high-content assay-based scFPM can have a significant value in clinical therapy guidance based on functional dependencies of each patient's cancer. See related commentary by Letai, p. 290. This article is highlighted in the In This Issue feature, p. 275
    Materialart: Online-Ressource
    ISSN: 2159-8274 , 2159-8290
    Sprache: Englisch
    Verlag: American Association for Cancer Research (AACR)
    Publikationsdatum: 2022
    ZDB Id: 2607892-2
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 2
    In: Cancer Research, American Association for Cancer Research (AACR), Vol. 77, No. 6 ( 2017-03-15), p. 1261-1270
    Kurzfassung: Mastocytosis is a term used to denote a heterogeneous group of conditions defined by the expansion and accumulation of clonal (neoplastic) tissue mast cells in various organs. The classification of the World Health Organization (WHO) divides the disease into cutaneous mastocytosis, systemic mastocytosis, and localized mast cell tumors. On the basis of histomorphologic criteria, clinical parameters, and organ involvement, systemic mastocytosis is further divided into indolent systemic mastocytosis and advanced systemic mastocytosis variants, including aggressive systemic mastocytosis and mast cell leukemia. The clinical impact and prognostic value of this classification has been confirmed in numerous studies, and its basic concept remains valid. However, refinements have recently been proposed by the consensus group, the WHO, and the European Competence Network on Mastocytosis. In addition, new treatment options are available for patients with advanced systemic mastocytosis, including allogeneic hematopoietic stem cell transplantation and multikinase inhibitors directed against KIT D816V and other key signaling molecules. Our current article provides an overview of recent advances in the field of mastocytosis, with emphasis on classification, prognostication, and emerging new treatment options in advanced systemic mastocytosis. Cancer Res; 77(6); 1261–70. ©2017 AACR.
    Materialart: Online-Ressource
    ISSN: 0008-5472 , 1538-7445
    RVK:
    RVK:
    Sprache: Englisch
    Verlag: American Association for Cancer Research (AACR)
    Publikationsdatum: 2017
    ZDB Id: 2036785-5
    ZDB Id: 1432-1
    ZDB Id: 410466-3
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 3
    In: Clinical Cancer Research, American Association for Cancer Research (AACR), Vol. 11, No. 19 ( 2005-10-01), p. 6787-6792
    Kurzfassung: Purpose: Myelomastocytic leukemia is a term used for patients with advanced myeloid neoplasms, in whom elevated numbers of immature atypical mast cells are found, but criteria for a primary mast cell disease are not met. The origin of mast cells in these patients is presently unknown. Patient and Methods: We have analyzed clonality of mast cells in an 18-year-old patient suffering from acute myeloid leukemia with a complex karyotype including a t(8;21) and mastocytic transformation with a huge increase in immature mast cells and elevated serum tryptase level, but no evidence for a primary mast cell disease/mastocytosis. Results: As assessed by in situ fluorescence hybridization combined with tryptase staining, both the tryptase-negative blast cells and the tryptase-positive mast cells were found to contain the t(8;21)-specific AML1/ETO fusion gene. Myeloablative stem cell transplantation resulted in complete remission with consecutive disappearance of AML1/ETO transcripts, decrease of serum tryptase to normal range, and disappearance of neoplastic mast cells. Conclusion: These data suggest that mast cells directly derive from the leukemic clone in patients with myelomastocytic leukemia.
    Materialart: Online-Ressource
    ISSN: 1078-0432 , 1557-3265
    RVK:
    Sprache: Englisch
    Verlag: American Association for Cancer Research (AACR)
    Publikationsdatum: 2005
    ZDB Id: 1225457-5
    ZDB Id: 2036787-9
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 4
    In: Cancer Research, American Association for Cancer Research (AACR), Vol. 83, No. 7_Supplement ( 2023-04-04), p. 6168-6168
    Kurzfassung: Despite a detailed understanding of the genes mutated in myelodysplastic syndromes (MDS), diagnostic and treatment decisions for patients with MDS rely primarily on clinical and cytogenetic variables as considered by the Revised International Prognostic Scoring System (IPSS-R). Here we describe the recently developed Molecular IPSS (IPSS-M), a clinico-genomic risk stratification system that considers clinical, cytogenetic and genetic parameters; the implementation of a web portal to facilitate its adoption, a strategy to handle missing variables, and the worldwide utilization of the web calculator as a clinical support tool. The IPSS-M was trained on 2,957 clinically annotated diagnostic MDS samples profiled for mutations in 156 driver genes. To maximize the clinical applicability of the IPSS-M and account for missing genetic data (i.e genes missing from a sequencing panel), we implemented a strategy to calculate a risk score under three scenarios: best, worst and average. Last, we developed an online calculator as a standalone single-page web application using VueJs, and D3Js for the interactive visualizations, deployed through a CI/CD pipeline on AWS, where collection of anonymous usage analytics allows to track adoption and usability of the new proposed model. The model incorporates clinical, morphological, genetic variables informed by cytogenetics and constructed from the presence of oncogenic mutations in 31 genes. It delivers a unique risk score for each individual patient, as well as an assignment to one of six IPSS-M risk strata. Compared to the IPSS-R the IPSS-M re-stratified 46% of MDS patients. The model was validated in an external dataset of 754 MDS patients. We released an open-access IPSS-M web calculator available at https://mds-risk-model.com. By specifying the patient clinical and molecular profiles, the tool returns the patient-specific IPSS-M risk score and category, and the probability estimates over time for three clinical endpoints, i.e. leukemia free survival (LFS), overall survival, and incidence of leukemic transformation. Since its launch in June 2022, the calculator has been used by & gt;6000 users in & gt;75 countries, reaching a daily average of 100 users per day. Risks have been calculated for & gt;45,000 patient profiles. 99.28% of the sessions initiated reach an IPSS-M score, suggesting that the calculator is intuitive and easy to use. We trained and validated the IPSS-M on 3,711 patients, a patient tailored risk stratification tool for patients with MDS that considers clinical, morphological and genetic variables inclusive of cytogenetics and mutations in one of 31 genes. The development of a web based tool was instrumental to the global dissemination of the model, enabling non-expert users to leverage the power of molecular biomarkers in risk stratification for patients with MDS. Citation Format: Elsa Bernard, Juan E. Arango Ossa, Heinz Tuechler, Peter L. Greenberg, Robert P. Hasserjian, Yasuhito Nannya, Sean M. Devlin, Maria Creignou, Philippe Pinel, Lily Monier, Juan S. Medina-Martinez, Dylan Domenico, Martin Jädersten, Ulrich Germing, Guillermo Sanz, Arjan A. van de Loosdrecht, Olivier Kosmider, Matilde Y. Follo, Felicitas Thol, Lurdes Zamora, Ronald F. Pinheiro, Andrea Pellagatti, Detlef Haase, Pierre Fenaux, Monika Belickova, Michael R. Savona, Virginia M. Klimek, Fabio P. Santos, Jacqueline Boultwood, Ioannis Kotsianidis, Valeria Santini, Francesc Solé, Uwe Platzbecker, Michael Heuser, Peter Valent, Kazuma Ohyashiki, Carlo Finelli, Maria Teresa Voso, Lee-Yung Shih, Michaela Fontenay, Joop H. Jansen, José Cervera, Norbert Gattermann, Benjamin L. Ebert, Rafael Bejar, Luca Malcovati, Mario Cazzola, Seishi Ogawa, Eva Hellström-Lindberg, Elli Papaemmanuil. Implementation and adoption of a web tool to support precision diagnostic and treatment decisions for patient with myelodysplastic syndromes [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6168.
    Materialart: Online-Ressource
    ISSN: 1538-7445
    Sprache: Englisch
    Verlag: American Association for Cancer Research (AACR)
    Publikationsdatum: 2023
    ZDB Id: 2036785-5
    ZDB Id: 1432-1
    ZDB Id: 410466-3
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  • 5
    In: Cancer Research, American Association for Cancer Research (AACR), Vol. 70, No. 4 ( 2010-02-15), p. 1513-1523
    Kurzfassung: In most patients with chronic myeloid leukemia (CML), the disease can be kept under control using the BCR/ABL kinase inhibitor imatinib. Nevertheless, resistance or intolerance to imatinib and other BCR/ABL inhibitors may occur during therapy. Therefore, CML research is focusing on novel targets and targeted drugs. Polo-like kinase 1 (Plk1) is a serine/threonine kinase that plays an essential role in mitosis. In this study, we examined the expression of Plk1 in CML cells and its potential role as a therapeutic target. Plk1 was found to be expressed in phosphorylated form in the CML cell line K562 as well as in primary CML cells in all patients tested. Inhibition of BCR/ABL by imatinib or nilotinib (AMN107) led to decreased expression of the Plk1 protein in CML cells, suggesting that BCR/ABL promotes Plk1 generation. Silencing of Plk1 in CML cells by a small interfering RNA approach was followed by cell cycle arrest and apoptosis. Furthermore, the Plk1-targeting drug BI 2536 was found to inhibit proliferation of imatinib-sensitive and imatinib-resistant CML cells, including leukemic cells, carrying the T315 mutation of BCR/ABL with reasonable IC50 values (1–50 nmol/L). The growth-inhibitory effects of BI 2536 on CML cells were found to be associated with cell cycle arrest and apoptosis. Moreover, BI 2536 was found to synergize with imatinib and nilotinib in producing growth inhibition in CML cells. In conclusion, Plk1 is expressed in CML cells and may represent a novel, interesting target in imatinib-sensitive and imatinib-resistant CML. Cancer Res; 70(4); 1513–23
    Materialart: Online-Ressource
    ISSN: 0008-5472 , 1538-7445
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    Sprache: Englisch
    Verlag: American Association for Cancer Research (AACR)
    Publikationsdatum: 2010
    ZDB Id: 2036785-5
    ZDB Id: 1432-1
    ZDB Id: 410466-3
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  • 6
    In: Clinical Cancer Research, American Association for Cancer Research (AACR), Vol. 22, No. 8 ( 2016-04-15), p. 2051-2061
    Kurzfassung: Purpose: In chronic myelogenous leukemia (CML), leukemic stem cells (LSC) represent a critical target of therapy. However, little is known about markers and targets expressed by LSCs. The aim of this project was to identify novel relevant markers of CML LSCs. Experimental Design: CML LSCs were examined by flow cytometry, qPCR, and various bioassays. In addition, we examined the multipotent CD25+ CML cell line KU812. Results: In contrast to normal hematopoietic stem cells, CD34+/CD38− CML LSCs expressed the IL-2 receptor alpha chain, IL-2RA (CD25). STAT5 was found to induce expression of CD25 in Lin−/Sca-1+/Kit+ stem cells in C57Bl/6 mice. Correspondingly, shRNA-induced STAT5 depletion resulted in decreased CD25 expression in KU812 cells. Moreover, the BCR/ABL1 inhibitors nilotinib and ponatinib were found to decrease STAT5 activity and CD25 expression in KU812 cells and primary CML LSCs. A CD25-targeting shRNA was found to augment proliferation of KU812 cells in vitro and their engraftment in vivo in NOD/SCID-IL-2Rγ−/− mice. In drug-screening experiments, the PI3K/mTOR blocker BEZ235 promoted the expression of STAT5 and CD25 in CML cells. Finally, we found that BEZ235 produces synergistic antineoplastic effects on CML cells when applied in combination with nilotinib or ponatinib. Conclusions: CD25 is a novel STAT5-dependent marker of CML LSCs and may be useful for LSC detection and LSC isolation in clinical practice and basic science. Moreover, CD25 serves as a growth regulator of CML LSCs, which may have biologic and clinical implications and may pave the way for the development of new more effective LSC-eradicating treatment strategies in CML. Clin Cancer Res; 22(8); 2051–61. ©2015 AACR.
    Materialart: Online-Ressource
    ISSN: 1078-0432 , 1557-3265
    RVK:
    Sprache: Englisch
    Verlag: American Association for Cancer Research (AACR)
    Publikationsdatum: 2016
    ZDB Id: 1225457-5
    ZDB Id: 2036787-9
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  • 7
    In: Cancer Research, American Association for Cancer Research (AACR), Vol. 65, No. 20 ( 2005-10-15), p. 9436-9444
    Kurzfassung: Chronic myeloid leukemia (CML) is a myeloproliferative disease in which BCR/ABL enhances survival of leukemic cells through modulation of proapoptotic and antiapoptotic molecules. Recent data suggest that proapoptotic Bcl-2–interacting mediator (Bim) plays a role as a tumor suppressor in myeloid cells, and that leukemic cells express only low amounts of this cell death activator. We here show that primary CML cells express significantly lower amounts of bim mRNA and Bim protein compared with normal cells. The BCR/ABL inhibitors imatinib and AMN107 were found to promote expression of Bim in CML cells. To provide direct evidence for the role of BCR/ABL in Bim modulation, we employed Ba/F3 cells with doxycycline-inducible expression of BCR/ABL and found that BCR/ABL decreases expression of bim mRNA and Bim protein in these cells. The BCR/ABL-induced decrease in expression of Bim was found to be a posttranscriptional event that depended on signaling through the mitogen-activated protein kinase pathway and was abrogated by the proteasome inhibitor MG132. Interestingly, MG132 up-regulated the expression of bim mRNA and Bim protein and suppressed the growth of Ba/F3 cells containing wild-type BCR/ABL or imatinib-resistant mutants of BCR/ABL. To show functional significance of “Bim reexpression,” a Bim-specific small interfering RNA was applied and found to rescue BCR/ABL-transformed leukemic cells from imatinib-induced cell death. In summary, our data identify BCR/ABL as a Bim suppressor in CML cells and suggest that reexpression of Bim by novel tyrosine kinase inhibitors, proteasome inhibition, or by targeting signaling pathways downstream of BCR/ABL may be an attractive therapeutic approach in imatinib-resistant CML.
    Materialart: Online-Ressource
    ISSN: 0008-5472 , 1538-7445
    RVK:
    RVK:
    Sprache: Englisch
    Verlag: American Association for Cancer Research (AACR)
    Publikationsdatum: 2005
    ZDB Id: 2036785-5
    ZDB Id: 1432-1
    ZDB Id: 410466-3
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 8
    In: Cancer Research, American Association for Cancer Research (AACR), Vol. 75, No. 15_Supplement ( 2015-08-01), p. 3957-3957
    Kurzfassung: Systemic mastocytosis (SM) includes a heterogeneous group of disorders ranging from indolent SM to the rare and aggressive mast cell leukemia (MCL). Somatic mutations in the KIT receptor kinase (most frequently, D816V) can be detected in & gt;90% of patients and are thought to play an important pathogenetic role. Nevertheless, morphological and clinical diversity, as well as the fact that some patients are negative for KIT mutations, suggest that the underlying molecular picture is far from being fully elucidated. To shed further light on this issue, we undertook an integrated molecular genetic study of a KIT gene mutation-negative MCL case who came to our attention in 2012. After having obtained written informed consent, we extracted genomic DNA and total RNA from purified mast cells (MCs) isolated from bone marrow at diagnosis and at progression, as well as DNA from saliva, and performed whole exome sequencing (WES) and RNA-seq on an HiSeq1000 (Illumina, San Diego CA). High resolution karyotyping was also performed with Cytoscan HD arrays (Affymetrix, Santa Clara CA). Among the mutated genes detected in MCs but not in saliva by WES, SETD2 stood out among others because two loss-of-function mutations (a nonsense and a frameshift mutation) inactivating both alleles of the gene were identified. Western Blotting (WB) confirmed the expression of the truncated SETD2 isoform resulting from the nonsense mutation. The SETD2 gene encodes a histone methyltransferase responsible for trimethylation of Lysine 36 of histone H3 (H3K36Me3), a key hystone mark associated not only with active chromatin but also with transcriptional elongation, alternative splicing, DNA replication and repair. Loss of the highly conserved WW and SRI domains was predicted to impair SETD2 binding with RNA polymeraseII and hNRNP L, as confirmed by co-immunoprecipitation. Accordingly, RNA-seq showed evidence of spurious transcripts initiated from cryptic promoter-like sequences within genes as well as non-canonical splice isoforms. More importantly, WB confirmed that H3K36Me3 was completely abrogated. In line with the role of SETD2-dependent H3K36Me3 in DNA repair and genome stability, Cytoscan HD arrays and WES showed that several losses at many chromosomal loci, together with more than 70 additional point mutations, undetectable at diagnosis, were acquired at the time of progression. Absence of SETD2 protein expression and/or reduced H3K36Me3 were detected in 3/3 additional MCLs and in 6/8 aggressive SMs so far screened. Our data point to epigenetic regulation and/or DNA repair as candidate pathways deserving further investigation in SM - in an attempt to elucidate the mechanisms underlying enhanced clinical aggressiveness and to identify more effective treatment modalities. Molecular characterization of 10 additional MCLs and aggressive SMs is ongoing. Supported by FP7 NGS-PTL project and Progetto Regione-Università 2010-12(L. Bolondi) Citation Format: Simona Soverini, Caterina De Benedittis, Michela Rondoni, Manuela Mancini, Cristina Papayannidis, Luca Zazzeroni, Viviana Guadagnuolo, Elisa Zago, Francesca Griggio, Alberto Ferrarini, Marianna Garonzi, Massimo Delledonne, Giorgina Specchia, Roberta Zanotti, Omar Perbellini, Livio Pagano, Michele Cavo, Peter Valent, Giovanni Martinelli. Integrated molecular characterization of mast cell leukemia reveals recurrent inactivation of the SETD2 tumor suppressor gene. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3957. doi:10.1158/1538-7445.AM2015-3957
    Materialart: Online-Ressource
    ISSN: 0008-5472 , 1538-7445
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    RVK:
    Sprache: Englisch
    Verlag: American Association for Cancer Research (AACR)
    Publikationsdatum: 2015
    ZDB Id: 2036785-5
    ZDB Id: 1432-1
    ZDB Id: 410466-3
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  • 9
    In: Cancer Research, American Association for Cancer Research (AACR), Vol. 77, No. 13_Supplement ( 2017-07-01), p. 1184-1184
    Kurzfassung: Activation of the transcription factor STAT5 is essential for the pathogenesis of acute myeloid leukemia (AML) containing the FLT3 internal tandem duplication (ITD). FLT3 ITD is a constitutively active tyrosine kinase (TK) that drives the activation of STAT5 leading to the growth and survival of AML cells. Although there has been some success in identifying TK inhibitors that block the function of FLT3 ITD, treatment options are still limited. This is mainly due to drug resistance development by mutations that allow for the continued activation of STATs. Since STAT5 represents a critical mediator of malignant cellular behavior and sits at the convergence point of many kinase pathways, the direct targeting of STAT5 may be an effective means of overcoming this resistance to TK inhibitors. First, we screened a library of potential STAT5 inhibitors for specific SH2 domain binders using a fluorescent polarization assay. Thereby, we identified small inhibitory molecules, called AC-3-019 and AC-4-130, that bind to the SH2 domain of STAT5, subsequently resulting in the disruption of the reciprocal STAT5-phosphopeptide interactions. They efficiently blocked kinase-mediated phosphorylation, dimer formation, nuclear translocation, DNA binding and STAT5 mediated target gene expression. Further, we observed a time- and dose-dependent impairment of proliferation, blocked cell cycle progression and increased apoptosis. Studies with human AML patient-derived samples similarly showed an induction of apoptotic cell death and decreased colony forming capabilities. A combinatorial drug screen revealed synergistic effects with TK inhibitors, as well as with drugs standardly used in the treatment of AML patients, e.g. Cytarabine. Finally, AC-3-019 and AC-4-130 significantly suppressed tumor growth in vivo without general toxicity in healthy organs. Overall, our findings indicate that AC-3-019 and AC-4-130 are potent and selective inhibitors of STAT5. These compounds provide lead structures for further chemical modifications and clinical development for the identification of compounds to improve existing therapies. Citation Format: Bettina Wingelhofer, Barbara Maurer, Elizabeth C. Heyes, Patricia Freund, Abbarna A. Cumaraswamy, Jisung Park, Stefan Kubicek, Peter Valent, Patrick T. Gunning, Richard Moriggl. Characterization of novel STAT5 inhibitors to interfere with the oncogenic activities of STAT5 in hematopoietic diseases [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 1184. doi:10.1158/1538-7445.AM2017-1184
    Materialart: Online-Ressource
    ISSN: 0008-5472 , 1538-7445
    RVK:
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    Sprache: Englisch
    Verlag: American Association for Cancer Research (AACR)
    Publikationsdatum: 2017
    ZDB Id: 2036785-5
    ZDB Id: 1432-1
    ZDB Id: 410466-3
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 10
    In: Molecular Cancer Research, American Association for Cancer Research (AACR), Vol. 14, No. 1_Supplement ( 2016-01-01), p. B01-B01
    Kurzfassung: The metabolic oncogene fatty acid synthase (FASN) is overexpressed in 80% of ovarian cancers (OC) and indicates poor prognosis. Exposure of OC to inhibitors of FASN elicits a complex stress response that interferes with receptor-PI3K-mTORC1 signaling (briefly designated ‘PI3K pathway’). Here we demonstrate that FASN inhibitors capitalize on multiple mechanisms to interfere with the PI3K pathway, and that silencing this cascade is crucial for the anticancer action of the drugs. Data were obtained using thin-layer chromatography, ELISA, Western blotting, quantitative micropatterning and growth assays, respectively. Exposure of OC cells (SKOV3, OVCAR-3) to FASN inhibitors (C75, G28UCM) causes lipid redistribution toward storage lipids, whereas membrane lipid rafts and signaling lipids are diminished, which significantly impairs EGF receptor/ErbB/HER function and expression. A severe depletion of phosphatidylinositol (3,4,5) trisphosphate (PIP3), which represents the crucial product of PI3K action, is associated with drug-dependent silencing of AKT. Moreover, FASN blockers rapidly stimulate expression of the stress response gene REDD1 (RTP801/Dig2/DDIT4) followed by slow activation of the energy sensor AMPK. Induction of these mTORC1 upstream repressors has been found to block downstream phosphorylation of ribosomal S6 protein. Moreover, long-term stress imposed by persistent FASN blockade leads to accelerated degradation of signaling proteins. Interestingly, concurrent targeting of the PI3K pathway using the dual PI3K/mTOR blocker NVP-BEZ235 does not aggravate the FASN anticancer drug effects. However, forced expression of constitutive active AKT counteracts FASN inhibitor-mediated mTORC1 silencing and abrogates growth arrest. Our data thus suggest that FASN inhibitors by themselves can efficiently eliminate PI3K downstream activity. This mechanism appears crucial for the anticancer effect, which cannot be augmented by co-exposure to drugs that target the very same pathway. On the other hand, silencing PI3K signaling by FASN inhibitors was found to release a negative feedback loop toward MAPK. Thus, FASN drug-mediated PI3K silencing is associated with cross-activation of ERK1/2. Accordingly, co-treatment with the MEK inhibitor selumetinib (AZD6244) significantly improves the anticancer action of FASN inhibitors, whereas introduction of constitutive active MEK does not alter FASN drug-induced growth inhibition. Collectively these data demonstrate that FASN inhibitors utilize a whole panel of different mechanisms to abrogate receptor-PI3K-mTORC1 signaling, which represents at least one of the crucial mechanisms of anticancer action of these compounds. Supported by Medical Scientific Fund of the Mayor of the City of Vienna & ‘Initiative Krebsforschung’ of the Medical University Vienna, Austria. Citation Format: Renate Wagner, Katharina Pröstling, Daniel Veigel, Gerald Stübiger, Michael Grusch, Julian Weghuber, Christian Singer, Heidrun Karlic, Ramón Colomer, Bellinda Benhamú, María Luz López-Rodríguez, Fausto Hegardt, Jordi García, Dolors Serra, Peter Valent, Thomas Grunt. Multilevel interference with receptor-PI3K-mTORC1 signaling is key mechanism for anticancer activity of fatty acid synthase inhibitors. [abstract]. In: Proceedings of the AACR Special Conference: Metabolism and Cancer; Jun 7-10, 2015; Bellevue, WA. Philadelphia (PA): AACR; Mol Cancer Res 2016;14(1_Suppl):Abstract nr B01.
    Materialart: Online-Ressource
    ISSN: 1541-7786 , 1557-3125
    Sprache: Englisch
    Verlag: American Association for Cancer Research (AACR)
    Publikationsdatum: 2016
    ZDB Id: 2097884-4
    SSG: 12
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