Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
22
pubmed:dateCreated
2011-6-3
pubmed:abstractText
We studied leukemic stem cells (LSCs) in a Smad4(-/-) mouse model of acute myelogenous leukemia (AML) induced either by the HOXA9 gene or by the fusion oncogene NUP98-HOXA9. Although Hoxa9-Smad4 complexes accumulate in the cytoplasm of normal hematopoietic stem cells and progenitor cells (HSPCs) transduced with these oncogenes, there is no cytoplasmic stabilization of HOXA9 in Smad4(-/-) HSPCs, and as a consequence increased levels of Hoxa9 is observed in the nucleus leading to increased immortalization in vitro. Loss of Smad4 accelerates the development of leukemia in vivo because of an increase in transformation of HSPCs. Therefore, the cytoplasmic binding of Hoxa9 by Smad4 is a mechanism to protect Hoxa9-induced transformation of normal HSPCs. Because Smad4 is a potent tumor suppressor involved in growth control, we developed a strategy to modify the subcellular distribution of Smad4. We successfully disrupted the interaction between Hoxa9 and Smad4 to activate the TGF-? pathway and apoptosis, leading to a loss of LSCs. Together, these findings reveal a major role for Smad4 in the negative regulation of leukemia initiation and maintenance induced by HOXA9/NUP98-HOXA9 and provide strong evidence that antagonizing Smad4 stabilization by these oncoproteins might be a promising novel therapeutic approach in leukemia.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
1528-0020
pubmed:author
pubmed:issnType
Electronic
pubmed:day
2
pubmed:volume
117
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
5918-30
pubmed:meshHeading
pubmed-meshheading:21471525-Animals, pubmed-meshheading:21471525-Apoptosis, pubmed-meshheading:21471525-Blotting, Western, pubmed-meshheading:21471525-Bone Marrow Transplantation, pubmed-meshheading:21471525-Cell Nucleus, pubmed-meshheading:21471525-Cell Transformation, Neoplastic, pubmed-meshheading:21471525-Chromatin Immunoprecipitation, pubmed-meshheading:21471525-Cytoplasm, pubmed-meshheading:21471525-Flow Cytometry, pubmed-meshheading:21471525-Hematopoietic Stem Cells, pubmed-meshheading:21471525-Homeodomain Proteins, pubmed-meshheading:21471525-Humans, pubmed-meshheading:21471525-Immunoprecipitation, pubmed-meshheading:21471525-Leukemia, Myeloid, Acute, pubmed-meshheading:21471525-Mice, pubmed-meshheading:21471525-Mice, Inbred C57BL, pubmed-meshheading:21471525-Mice, Knockout, pubmed-meshheading:21471525-Nuclear Pore Complex Proteins, pubmed-meshheading:21471525-Oncogene Proteins, Fusion, pubmed-meshheading:21471525-RNA, Messenger, pubmed-meshheading:21471525-Reverse Transcriptase Polymerase Chain Reaction, pubmed-meshheading:21471525-Smad4 Protein, pubmed-meshheading:21471525-Transforming Growth Factor beta
pubmed:year
2011
pubmed:articleTitle
Smad4 binds Hoxa9 in the cytoplasm and protects primitive hematopoietic cells against nuclear activation by Hoxa9 and leukemia transformation.
pubmed:affiliation
Molecular Medicine and Gene Therapy, Lund Stem Cell Center, Lund, Sweden.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't