title: Targeted degradation of the AML1/MDS1/EVI1 oncoprotein by arsenic trioxide.
abstract: Arsenic trioxide (ATO) has been found to be an effective treatment for acute promyelocytic leukemia patients and is being tested for treating other hematologic malignancies. We have previously shown that AML1/MDS1/EVI1 (AME), a fusion gene generated by a t(3;21)(q26;q22) translocation found in patients with chronic myelogenous leukemia during blast phase, myelodysplastic syndrome, or acute myelogenous leukemia (AML), impairs hematopoiesis and eventually induces an AML in mice. Both fusion partners of AME, AML1 and MDS1/EVI1, encode transcription factors and are also targets of a variety of genetic abnormalities in human hematologic malignancies. In addition, aberrant expression of ectopic viral integration site 1 (EVI1) has also been found in solid tumors, such as ovarian and colon cancers. In this study, we examined whether ATO could target AME and related oncoproteins. We found that ATO used at therapeutic levels degrades AME. The ATO treatment induces differentiation and apoptosis in AME leukemic cells in vitro as well as reduces tumor load and increases the survival of mice transplanted with these cells. We further found that ATO targets AME via both myelodysplastic syndrome 1 (MDS1) and EVI1 moieties and degrades EVI1 via the ubiquitin-proteasome pathway and MDS1 in a proteasome-independent manner. Our results suggest that ATO could be used as a part of targeted therapy for AME-, AML1/MDS1-, MDS1/EVI1-, and EVI1-positive human cancers.
authors.affiliation: Rosenstiel Basic Medical Sciences Research Center, Department of Biology, Brandeis University, Waltham, Massachusetts 02454-9110, USA.
authors.forename: David
authors.initials: D
authors.lastname: Shackelford
authors.forename: Candia
authors.initials: C
authors.lastname: Kenific
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Blusztajn
authors.forename: Samuel
authors.initials: S
authors.lastname: Waxman
authors.forename: Ruibao
authors.initials: R
authors.lastname: Ren
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D000077237:Arsenic Trioxide; D001152:Arsenicals / Q000494:pharmacology*; D015153:Blotting, Western; D002454:Cell Differentiation / Q000187:drug effects; D045744:Cell Line, Tumor; D050676:Core Binding Factor Alpha 2 Subunit / Q000235:genetics / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D015536:Down-Regulation / Q000187:drug effects; D005434:Flow Cytometry; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D006131:Growth Inhibitors / Q000494:pharmacology; D006801:Humans; D007942:Leukemia, Experimental / Q000235:genetics / Q000473:pathology / Q000517:prevention & control; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D041681:NIH 3T3 Cells; D015514:Oncogene Proteins, Fusion / Q000235:genetics / Q000378:metabolism*; D010087:Oxides / Q000494:pharmacology*; D046988:Proteasome Endopeptidase Complex / Q000378:metabolism; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction / Q000187:drug effects; D016019:Survival Analysis; D014162:Transfection; D025801:Ubiquitin / Q000378:metabolism
chemical_list: C460199:AML1-MDS1-EVI1 fusion protein, human; D001152:Arsenicals; D050676:Core Binding Factor Alpha 2 Subunit; D006131:Growth Inhibitors; D015514:Oncogene Proteins, Fusion; D010087:Oxides; D012097:Repressor Proteins; D025801:Ubiquitin; D046988:Proteasome Endopeptidase Complex; D000077237:Arsenic Trioxide