DOCSLIB.ORG

Abstract: Dissecting PDGFRB Function in NPM- ALK Driven Lymphoma

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Abstract: Dissecting PDGFRB Function in NPM- ALK Driven Lymphoma University of Veterinary Medicine, Vienna Institute of Pathology and Forensic Veterinary Medicine Abstract: Dissecting PDGFRB function in NPM- ALK driven lymphoma Lukas KENNER, Pathology of Laboratory Animals The study of tumor animal models of proven clinical relevance is essential to advance clinical practice. Anaplastic large cell lymphoma (ALCL) is a malignant T-cell Non-Hodgkin lymphoma and frequently associated with the t(2;5) translocation resulting in expression of the Nucleophosmin-Anaplastic Lymphoma Kinase (NPM-ALK) fusion protein. Recent studies by us identified AP-1 transcription factors (TF) JUNB and cJUN as downstream effectors of NPM-ALK. These TFs directly upregulate platelet derived growth factor receptor B (PDGFRB) expression in lymphoma cells. Based on these findings we established a mouse model for ALCL by expressing NPM-ALK under the CD4 promoter, which is the only animal model reflecting the clinical progression and metastatic potential of the disease. Genetic ablation of cJUN and JUNB in this model did not affect tumor incidence, however lymphomas displayed reduced progression, indicated by reduced vascularization as well as a loss of dissemination. This resulted in extended survival; therapeutic inhibition of PDGFRB with the kinase inhibitor imatinib markedly prolonged the life of NPM-ALK transgenic mice. We therefore conclude that cJUN/JUNB driven expression of PDGFRB in lymphoma cells induces stromal alterations in the microenvironment of the initial ALCL tumor, which are essential for tumor progression and dissemination. This is pointing towards tumor cell autonomous as well as microenvironmental functions of signaling cascades in ALK driven ALCL. Therefore this mouse model is suitable to study tumor stroma interactions, which are currently lacking. We thus propose to use the CD4- NPM-ALK mouse as a novel model system to study the role of tumor stroma interaction for tumor initiation, progression and dissemination We plan to analyse the communication between tumor cells and the microenvironment through signaling pathways contributing to tumor progression. The focus of this project will be the investigation of established signaling pathways such as PDGF/PDGFR or CDXL12/CDXR4 in tumor-stroma crosstalk in NPM-ALK lymphomas. To facilitate the project we want to analyse these signaling pathways in NPM-ALK tumor cells by genetic dissection of essential factors in the tumor cells and/or the stromal fibroblasts. This will be achieved in vivo by tumor (via CD4- Cre) or/and stroma specific (via FSP-Cre) deletion and in vitro by the use of the CRISP/Cas9 knockout technology, which will be followed by Xenotransplantation of genetically modified cell- lines. The tumors will be analyzed histologically, cell biologically and at the molecular level. Abstract: Dissecting PDGFRB function in NPM-ALK driven lymphoma Postdoc Call 2015 .
Load more

Recommended publications
  • Platelet-Derived Growth Factor Receptor Expression and Amplification in Choroid Plexus Carcinomas
    Modern Pathology (2008) 21, 265–270 & 2008 USCAP, Inc All rights reserved 0893-3952/08 $30.00 www.modernpathology.org Platelet-derived growth factor receptor expression and amplification in choroid plexus carcinomas Nina N Nupponen1,*, Janna Paulsson2,*, Astrid Jeibmann3, Brigitte Wrede4, Minna Tanner5, Johannes EA Wolff 6, Werner Paulus3, Arne O¨ stman2 and Martin Hasselblatt3 1Molecular Cancer Biology Program, University of Helsinki, Helsinki, Finland; 2Department of Oncology–Pathology, Cancer Centrum Karolinska, Karolinska Institutet, Stockholm, Sweden; 3Institute of Neuropathology, University Hospital Mu¨nster, Mu¨nster, Germany; 4Department of Pediatric Oncology, University of Regensburg, Regensburg, Germany; 5Department of Oncology, Tampere University Hospital, Tampere, Finland and 6Children’s Cancer Hospital, MD Anderson Cancer Center, Houston, TX, USA Platelet-derived growth factor (PDGF) receptor signaling has been implicated in the development of glial tumors, but not yet been examined in choroid plexus carcinomas, pediatric tumors with dismal prognosis for which novel treatment options would be desirable. Therefore, protein expression of PDGF receptors a and b as well as amplification status of the respective genes, PDGFRA and PDGFRB, were examined in a series of 22 patients harboring choroid plexus carcinoma using immunohistochemistry and chromogenic in situ hybridization (CISH). The majority of choroid plexus carcinomas expressed PDGF receptors with 6 cases (27%) displaying high staining scores for PDGF receptor a and 13 cases (59%) showing high staining scores for PDGF receptor b. Correspondingly, copy-number gains of PDGFRA were observed in 8 cases out of 12 cases available for CISH and 1 case displayed amplification (six or more signals per nucleus). The proportion of choroid plexus carcinomas with amplification of PDGFRB was even higher (5/12 cases).
    [Show full text]
  • Pdgfrβ Regulates Adipose Tissue Expansion and Glucose
    1008 Diabetes Volume 66, April 2017 Yasuhiro Onogi,1 Tsutomu Wada,1 Chie Kamiya,1 Kento Inata,1 Takatoshi Matsuzawa,1 Yuka Inaba,2,3 Kumi Kimura,2 Hiroshi Inoue,2,3 Seiji Yamamoto,4 Yoko Ishii,4 Daisuke Koya,5 Hiroshi Tsuneki,1 Masakiyo Sasahara,4 and Toshiyasu Sasaoka1 PDGFRb Regulates Adipose Tissue Expansion and Glucose Metabolism via Vascular Remodeling in Diet-Induced Obesity Diabetes 2017;66:1008–1021 | DOI: 10.2337/db16-0881 Platelet-derived growth factor (PDGF) is a key factor in The physiological roles of the vasculature in adipose tissue angiogenesis; however, its role in adult obesity remains have been attracting interest from the viewpoint of adipose unclear. In order to clarify its pathophysiological role, tissue expansion and chronic inflammation (1,2). White we investigated the significance of PDGF receptor b adipose tissue (WAT) such as visceral fat possesses the (PDGFRb) in adipose tissue expansion and glucose unique characteristic of plasticity; its volume may change metabolism. Mature vessels in the epididymal white several fold even after growth depending on nutritional adipose tissue (eWAT) were tightly wrapped with peri- conditions. Enlarged adipose tissue is chronically exposed cytes in normal mice. Pericyte desorption from vessels to hypoxia (3,4), which stimulates the production of angio- and the subsequent proliferation of endothelial cells genic factors for the supplementation of nutrients and were markedly increased in the eWAT of diet-induced oxygen to the newly enlarged tissue area (5). Selective ab- obese mice. Analyses with flow cytometry and adipose lation of the vasculature in WAT by apoptosis-inducible tissue cultures indicated that PDGF-B caused the de- peptides or the systemic administration of angiogenic in- PATHOPHYSIOLOGY tachment of pericytes from vessels in a concentration- hibitors has been shown to reduce WAT volumes and result dependent manner.
    [Show full text]
  • 60+ Genes Tested FDA-Approved Targeted Therapies & Gene Indicators
    ® 60+ genes tested ABL1, ABL2, ALK, AR, ARAF, ATM, ATR, BRAF, BRCA1*, BRCA2*, BTK, CCND1, CCND2, CCND3, CDK4, Somatic mutation detection CDK6, CDKN1A, CDKN1B, CDKN2A, CDKN2B, DDR1, DDR2, EGFR, ERBB2 (HER2), ESR1, FGFR1, FGFR2, for approved cancer therapies FGFR3, FGFR4, FLCN, FLT1, FLT3, FLT4, GNA11, GNAQ, HDAC1, HDAC2, HRAS, JAK1, JAK2, KDR, KIT, in solid tumors KRAS, MAP2K1, MET, MTOR, NF1, NF2, NRAS, PALB2, PARP1, PDGFRA, PDGFRB, PIK3CA, PIK3CD, PTCH1, PTEN, RAF1, RET, ROS1, SMO, SRC, STK11, TNK2, TSC1, TSC2 FDA-approved Targeted Therapies & Gene Indicators Abiraterone AR Necitumumab EGFR Ado-Trastuzumab ERBB2 (HER2) Nilotinib ABL1, ABL2, DDR1, DDR2, KIT, PDGFRA, PDGFRB Emtansine FGFR1, FGFR2, FGFR3, FLT1, FLT4, KDR, PDGFRA, Afatinib EGFR, ERBB2 (HER2) Nintedanib PDGFRB Alectinib ALK Olaparib ATM, ATR, BRCA1*, BRCA2*, PALB2, PARP1 Anastrozole ESR1 Osimertinib EGFR Axitinib FLT1, FLT4, KDR, KIT, PDGFRA, PDGFRB CDK4, CDK6, CCND1, CCND2, CCND3, CDKN1A, Palbociclib Belinostat HDAC1, HDAC2 CDKN1B, CDKN2A, CDKN2B Panitumumab EGFR Bicalutamide AR Panobinostat HDAC1, HDAC2 Bosutinib ABL1, SRC Pazopanib FLT1, FLT4, KDR, KIT, PDGFRA, PDGFRB Cabozantinib FLT1, FLT3, FLT4, KDR, KIT, MET, RET Pertuzumab ERBB2 (HER2) Ceritinib ALK ABL1, FGFR1, FGFR2, FGFR3, FGFR4, FLT1, FLT3, FLT4, Cetuximab EGFR Ponatinib KDR, KIT, PDGFRA, PDGFRB, RET, SRC Cobimetinib MAP2K1 Ramucirumab KDR Crizotinib ALK, MET, ROS1 Regorafenib ARAF, BRAF, FLT1, FLT4, KDR, KIT, PDGFRB, RAF1, RET Dabrafenib BRAF Ruxolitinib JAK1, JAK2 Dasatinib ABL1, ABL2, DDR1, DDR2, SRC, TNK2
    [Show full text]
  • PSM, a Mediator of PDGF-BB-, IGF-I-, and Insulin-Stimulated Mitogenesis
    Oncogene (2000) 19, 39 ± 50 ã 2000 Macmillan Publishers Ltd All rights reserved 0950 ± 9232/00 $15.00 www.nature.com/onc PSM, a mediator of PDGF-BB-, IGF-I-, and insulin-stimulated mitogenesis Heimo Riedel*,1,2, Nasim Yousaf1, Yuyuan Zhao4, Heping Dai1,3, Youping Deng1 and Jian Wang1 1Department of Biological Sciences, Wayne State University, Detroit, Michigan, MI 48202, USA; 2Member, Barbara Ann Karmanos Cancer Institute, Detroit, Michigan, MI 48201, USA PSM/SH2-B has been described as a cellular partner of Introduction the FceRI receptor, insulin receptor (IR), insulin-like growth factor-I (IGF-I) receptor (IGF-IR), and nerve The platelet-derived growth factor (PDGF) family growth factor receptor (TrkA). A function has been represents key mitogenic and chemotactic factors that proposed in neuronal dierentiation and development but have been exploited by the Simian sarcoma virus v-sis its role in other signaling pathways is still unclear. To oncogene which results in altered PDGF expression further elucidate the physiologic role of PSM we have (Water®eld et al., 1983). Normal cellular PDGF identi®ed additional mitogenic receptor tyrosine kinases appears in three distinct isoforms as any combination as putative PSM partners including platelet-derived of the PDGF A and B chains which act in paracrine growth factor (PDGF) receptor (PDGFR) beta, hepato- and autocrine mechanisms (Heldin, 1993). PDGF cyte growth factor receptor (Met), and ®broblast growth receptor (PDGFR) signal transduction appears to be factor receptor. We have mapped Y740 as a site of a largely membrane delineated event (Hughes et al., PDGFR beta that is involved in the association with 1996).
    [Show full text]
  • PDGFRB FISH for Gleevec Eligibility in Myelodysplastic Syndrome/Myeloproliferative Disease (MDS/MPD)
    PDGFRB FISH PRODUCT DATASHEET Proprietary Name: PDGFRB FISH for Gleevec Eligibility in Myelodysplastic Syndrome/Myeloproliferative Disease (MDS/MPD) Established Name: PDGFRB FISH for Gleevec in MDS/MPD INTENDED USE Humanitarian Device. Authorized by Federal law for use in the qualitative detection of PDGFRB gene rearrangement in patients with MDS/MPD. The effectiveness of this device for this use has not been demonstrated. Caution: Federal Law restricts this device to sale by or on the order of a licensed practitioner. PDGFRB FISH for Gleevec Eligibility in Myelodysplastic Syndrome/Myeloproliferative Disease (MDS/MPD) is an in vitro diagnostic test intended for the qualitative detection of PDGFRB gene rearrangement from fresh bone marrow samples of patients with MDS/MPD with a high index of suspicion based on karyotyping showing a 5q31~33 anomaly. The PDGFRB FISH assay is indicated as an aid in the selection of MDS/MPD patients for whom Gleevec® (imatinib mesylate) treatment is being considered. This assay is for professional use only and is to be performed at a single laboratory site. SUMMARY AND EXPLANATION OF THE TEST The PDGFRB FISH assay detects rearrangement of the PDGFRB locus at chromosome 5q31~33 in adult patients with myelodysplastic syndrome/myeloproliferative disease (MDS/MPD). The PDGFRB gene encodes a cell surface receptor tyrosine kinase that upon activation stimulates mesenchymal cell division. Rearrangement of PDGFRB has been demonstrated by classical cytogenetic analysis in an exceedingly small fraction of MDS/MPD patients (~1%), usually cases with a clinical phenotype of chronic myelomonocytic leukemia (CMML). In particular, these patients harbor a t(5:12)(q31;p12) translocation involving the PDGFRB and ETV6 genes.
    [Show full text]
  • Platelet-Derived Growth Factor Isoform Expression in Carbon Tetrachloride
    Laboratory Investigation (2008) 88, 1090–1100 & 2008 USCAP, Inc All rights reserved 0023-6837/08 $30.00 Platelet-derived growth factor isoform expression in carbon tetrachloride-induced chronic liver injury Erawan Borkham-Kamphorst1, Evgenia Kovalenko1, Claudia RC van Roeyen2, Nikolaus Gassler3, Michael Bomble1, Tammo Ostendorf 2,Ju¨rgen Floege2, Axel M Gressner1 and Ralf Weiskirchen1 Platelet-derived growth factor (PDGF) has an essential role in liver fibrogenesis, as PDGF-B and -D both act as potent mitogens on culture-activated hepatic stellate cells (HSCs). Induction of PDGF receptor type-b (PDGFRb) in HSC is well documented in single-dose carbon tetrachloride (CCl4)-induced acute liver injury. Of the newly discovered isoforms PDGF- C and -D, only PDGF-D shows significant upregulation in bile duct ligation (BDL) models. We have now investigated the expression of PDGF isoforms and receptors in chronic liver injury in vivo after long-term CCl4 treatment and demonstrated that isolated hepatocytes have the requisite PDGF signaling pathways, both in the naive state and when isolated from CCl4-treated rats. In vivo, PDGF gene expression showed upregulation of all PDGF isoforms and receptors, with values peaking at 4 weeks and decreasing to near basal levels by 8 and 12 weeks. Interestingly, PDGF-C increased significantly when compared to BDL-models. PDGF-A, PDGF-C and PDGF receptor type-a (PDGFRa) correlated closely with in- flammation and steatosis. Immunohistochemistry revealed expression of PDGF-B, -C and -D in areas corresponding to centrilobular necrosis, inflammation and fibrosis, whereas PDGF-A localized in regenerative hepatocytes. PDGFRb was identified along the fibrotic septa, whereas PDGFRa showed positive staining in fibrotic septa and regenerative hepa- tocytes.
    [Show full text]
  • PDGFRB FISH Patient Information Sheet
    PDGFRB FISH Patient Information Sheet You are receiving this information because you have been diagnosed with myelodysplastic syndrome/myeloproliferative disease or MDS/MPD. These are rare disorders in which the bone marrow makes either too few or too many blood cells. Certain patterns in the genes of these cells, called biomarkers, may be present that can help your physician in deciding what treatments might be best for you. A sample of your bone marrow can be tested for a specific biomarker called platelet‐derived growth factor receptor beta (PDGFRB) gene rearrangement. Measuring the presence of this PDGFRB gene rearrangement in the bone marrow, along with all other available clinical information, may aid in the assessment of patients diagnosed with MDS/MPD for whom Gleevec (imatinib) treatment is being considered. The PDGFRB FISH for Gleevec Eligibility in Myelodysplastic Syndrome/Myeloproliferative Disease (MDS/MPD) test (referred to as the PDGFRB FISH assay) is a “humanitarian use” device test developed by ARUP Laboratories. This test is approved by the U.S. Food and Drug Administration (FDA) as a "humanitarian use" device, which means the effectiveness of this device for this test has not been demonstrated. What is involved in the testing? If you choose to take part in this testing, a sample of your bone marrow will be tested with the PDGFRB FISH assay at ARUP Laboratories. The test results, along with all other available clinical and laboratory data, will be used to make decisions about your care. Risks of testing The assay tests for the presence of the gene rearrangement (positive result).
    [Show full text]
  • PDGFRB Gene Platelet Derived Growth Factor Receptor Beta
    PDGFRB gene platelet derived growth factor receptor beta Normal Function The PDGFRB gene provides instructions for making a protein called platelet-derived growth factor receptor beta (PDGFRb ), which is part of a family of proteins called receptor tyrosine kinases. Receptor tyrosine kinases transmit signals from the cell surface into the cell through a process called signal transduction. The PDGFRb protein is found in the cell membrane of certain cell types, where a protein called platelet- derived growth factor attaches (binds) to it. This binding turns on (activates) the PDGFRb protein, which then activates other proteins inside the cell by adding a cluster of oxygen and phosphorus atoms (a phosphate group) at specific positions. This process, called phosphorylation, leads to the activation of a series of proteins in multiple signaling pathways. The signaling pathways stimulated by the PDGFRb protein control many important processes in the cell such as growth and division (proliferation), movement, and survival. PDGFRb protein signaling is important for the development of many types of cells throughout the body. Health Conditions Related to Genetic Changes PDGFRB-associated chronic eosinophilic leukemia Genetic rearrangements (translocations) involving the PDGFRB gene cause a type of cancer of blood-forming cells called PDGFRB-associated chronic eosinophilic leukemia. This condition is characterized by an increased number of eosinophils, a type of white blood cell. The most common of these translocations brings together part of the PDGFRB gene with another gene called ETV6, whose function is to turn off gene activity. Together, these pieces create the ETV6-PDGFRB fusion gene. Occasionally, genes other than ETV6 are fused with the PDGFRB gene.
    [Show full text]
  • Transactivation of Pdgfrb by Dopamine D4 Receptor Does Not
    Chi et al. Molecular Brain 2010, 3:22 http://www.molecularbrain.com/content/3/1/22 RESEARCH Open Access Transactivation of PDGFRb by dopamine D4 receptor does not require PDGFRb dimerization Sum Shing Chi1†, Sandra M Vetiska1†, Robin S Gill2, Marilyn S Hsiung2, Fang Liu1,3*, Hubert HM Van Tol1,2,3 Abstract Growth factor-induced receptor dimerization and cross-phosphorylation are hallmarks of signal transduction via receptor tyrosine kinases (RTKs). G protein-coupled receptors (GPCRs) can activate RTKs through a process known as transactivation. The prototypical model of RTK transactivation involves ligand-mediated RTK dimerization and cross-phosphorylation. Here, we show that the platelet-derived growth factor receptor b (PDGFRb) transactivation by the dopamine receptor D4 (DRD4) is not dependent on ligands for PDGFRb. Furthermore, when PDGFRb dimer- ization is inhibited and receptor phosphorylation is suppressed to near basal levels, the receptor maintains its ability to be transactivated and is still effective in signaling to ERK1/2. Hence, the DRD4-PDGFRb-ERK1/2 pathway can occur independently of a PDGF-like ligand, PDGFRb cross-phosphorylation and dimerization, which is distinct from other known forms of transactivation of RTKs by GPCRs. Introduction D2 (DRD2) [5-7], b2 adrenergic receptor [8], M1 mus- Receptor tyrosine kinases (RTKs) consist of a large carinic receptor [9], angiotensin II receptor [10], lyso- family of receptors whose members serve a wide range phosphatidic acid (LPA) receptor [11], ET1 receptor of physiological functions including growth, differentia- [12] and thrombin receptor [12] have been shown to tion and synaptic modulation. The members of this transactivate either the epidermal growth factor receptor receptor family generally feature an extracellular ligand- (EGFR) or the platelet-derived growth factor receptor b binding domain, linked by a transmembrane domain to (PDGFRb).
    [Show full text]
  • NIH Public Access Author Manuscript Clin Pharmacol Ther
    NIH Public Access Author Manuscript Clin Pharmacol Ther. Author manuscript; available in PMC 2015 April 01. NIH-PA Author ManuscriptPublished NIH-PA Author Manuscript in final edited NIH-PA Author Manuscript form as: Clin Pharmacol Ther. 2014 April ; 95(4): 413–415. doi:10.1038/clpt.2014.8. Adaptive Reprogramming of the Breast Cancer Kinome TJ Stuhlmiller1, HS Earp2, and GL Johnson1 1Department of Pharmacology, Lineberger Comprehensive Cancer Center, University of North Carolina School of Medicine, Chapel Hill, North Carolina, USA 2Department of Medicine, Lineberger Comprehensive Cancer Center, University of North Carolina School of Medicine, Chapel Hill, North Carolina, USA Abstract Our understanding of cancer has grown considerably with recent advances in high-throughput genome and transcriptome sequencing, but techniques to comprehensively analyze protein activity are still in development. Methods to quantitatively measure the activation of signaling pathways within tumors at baseline and following therapeutic intervention will prove critical to the design of proper treatment regimens. Focusing on breast cancer, we present such a method to understand kinase signaling using multiplexed kinase inhibitor beads coupled with mass spectrometry (MIB/ MS). The National Cancer Institute Cancer Genome Atlas Project has brought us a deep understanding of the genetic landscape of human cancer. In samples from breast cancer patients, mutations in TP53 (37%) and PIK3CA (36%) account for the majority of somatic mutations observed across all subtypes,1
    [Show full text]
  • An Activated Receptor Tyrosine Kinase, TEL PDGF R, Cooperates With
    An activated receptor tyrosine kinase, TEL͞PDGF␤R, cooperates with AML1͞ETO to induce acute myeloid leukemia in mice Jay L. Grisolano, Julie O’Neal, Jennifer Cain, and Michael H. Tomasson* Departments of Medicine and Genetics, Division of Oncology, Washington University School of Medicine, Siteman Cancer Center, St. Louis, MO 63110 Edited by Janet D. Rowley, University of Chicago Medical Center, Chicago, IL, and approved June 5, 2003 (received for review March 22, 2003) The t(8;21)(q22;q22) translocation, occurring in 40% of patients was generated by an in vivo translocation by using Cre recom- with acute myeloid leukemia (AML) of the FAB-M2 subtype (AML binase also failed to develop disease (9). In another model, a with maturation), results in expression of the RUNX1-CBF2T1 conditional knock-in was generated by inserting an inducible AE [AML1-ETO (AE)] fusion oncogene. AML͞ETO may contribute to cDNA within a wild-type Runx1 allele (10). Although this leukemogenesis by interacting with nuclear corepressor complexes approach produced adult mice haploinsufficient at the Runx1 that include histone deacetylases, which mediate the repression of locus that were expressing AE in bone marrow, these mice did target genes. However, expression of AE is not sufficient to not develop AML unless treated with ENU (10). However, transform primary hematopoietic cells or cause disease in animals, myeloid progenitors from these mice did appear to have in- suggesting that additional mutations are required. Activating creased survival over wild-type progenitors when cultured in the mutations in receptor tyrosine kinases (RTK) are present in at least presence of cytokines (10).
    [Show full text]
  • Moguntinones—New Selective Inhibitors for the Treatment of Human Colorectal Cancer
    Published OnlineFirst April 17, 2014; DOI: 10.1158/1535-7163.MCT-13-0224 Molecular Cancer Small Molecule Therapeutics Therapeutics Moguntinones—New Selective Inhibitors for the Treatment of Human Colorectal Cancer Annett Maderer1, Stanislav Plutizki2, Jan-Peter Kramb2, Katrin Gopfert€ 1, Monika Linnig1, Katrin Khillimberger1, Christopher Ganser2, Eva Lauermann2, Gerd Dannhardt2, Peter R. Galle1, and Markus Moehler1 Abstract 3-Indolyl and 3-azaindolyl-4-aryl maleimide derivatives, called moguntinones (MOG), have been selected for their ability to inhibit protein kinases associated with angiogenesis and induce apoptosis. Here, we characterize their mode of action and their potential clinical value in human colorectal cancer in vitro and in vivo. MOG-19 and MOG-13 were characterized in vitro using kinase, viability, and apoptosis assays in different human colon cancer (HT-29, HCT-116, Caco-2, and SW480) and normal colon cell lines (CCD-18Co, FHC, and HCoEpiC) alone or in combination with topoisomerase I inhibitors. Intracellular signaling pathways were analyzed by Western blotting. To determine their potential to inhibit tumor growth in vivo, the human HT-29 tumor xenograft model was used. Moguntinones prominently inhibit several protein kinases associated with tumor growth and metastasis. Specific signaling pathways such as GSK3b and mTOR downstream targets b were inhibited with IC50 values in the nanomolar range. GSK3 signaling inhibition was independent of KRAS, BRAF, and PI3KCA mutation status. While moguntinones alone induced apoptosis only in concentra- tions >10 mmol/L, MOG-19 in combination with topoisomerase I inhibitors induced apoptosis synergistically at lower concentrations. Consistent with in vitro data, MOG-19 significantly reduced tumor volume and weight in combination with a topoisomerase I inhibitor in vivo.
    [Show full text]