Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
8
pubmed:dateCreated
2003-4-3
pubmed:abstractText
Activation of the phosphatidylinositol 3- kinase/AKT pathway antagonizes apoptosis in diverse cellular systems. We previously showed that human plasma activated AKT and potently blocked the ability of chlorambucil or gamma radiation to induce apoptosis of B-chronic lymphocytic leukemia (CLL) cells. Here we report experiments that identify albumin as the major component of plasma that blocks CLL cell killing by chlorambucil or radiation. Intact plasma depleted of albumin by chromatography on Cibacron blue-Sepharose or plasma from a subject with analbuminemia failed either to activate AKT or to protect CLL cells from chlorambucil-induced apoptosis. Both functions were restored by re-addition of albumin. The protective action of albumin as well as AKT activation was compromised by the binding of lipids. Fluorescence-activated cell sorter (FACScan) analysis demonstrated the uptake of fluoresceinated albumin by CLL cells. Accumulation of albumin in intracellular vesicles was also shown by confocal microscopy. Indirect inhibition of AKT activation by the phosphatidylinositol 3-kinase inhibitor LY294002 reversed the blockade of chlorambucil-induced killing by plasma albumin. The data suggest that activation of AKT consequent to binding of albumin by CLL cells blocks chlorambucil- and radiation-induced apoptosis. Strategies designed to block albumin-induced antiapoptotic signaling may, therefore, be of value in enhancing cytotoxic drug action on CLL cells.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/2-(4-morpholinyl)-8-phenyl-4H-1-benz..., http://linkedlifedata.com/resource/pubmed/chemical/AKT1 protein, human, http://linkedlifedata.com/resource/pubmed/chemical/Chlorambucil, http://linkedlifedata.com/resource/pubmed/chemical/Chromones, http://linkedlifedata.com/resource/pubmed/chemical/Enzyme Inhibitors, http://linkedlifedata.com/resource/pubmed/chemical/Morpholines, http://linkedlifedata.com/resource/pubmed/chemical/Phosphatidylinositol 3-Kinases, http://linkedlifedata.com/resource/pubmed/chemical/Protein-Serine-Threonine Kinases, http://linkedlifedata.com/resource/pubmed/chemical/Proto-Oncogene Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Proto-Oncogene Proteins c-akt, http://linkedlifedata.com/resource/pubmed/chemical/Radiation-Protective Agents, http://linkedlifedata.com/resource/pubmed/chemical/Recombinant Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Serum Albumin
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0006-4971
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
101
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
3174-80
pubmed:dateRevised
2010-11-18
pubmed:meshHeading
pubmed-meshheading:12480711-Apoptosis, pubmed-meshheading:12480711-Chlorambucil, pubmed-meshheading:12480711-Chromones, pubmed-meshheading:12480711-Endocytosis, pubmed-meshheading:12480711-Enzyme Inhibitors, pubmed-meshheading:12480711-Gamma Rays, pubmed-meshheading:12480711-Humans, pubmed-meshheading:12480711-Leukemia, Lymphocytic, Chronic, B-Cell, pubmed-meshheading:12480711-Microscopy, Confocal, pubmed-meshheading:12480711-Morpholines, pubmed-meshheading:12480711-Phosphatidylinositol 3-Kinases, pubmed-meshheading:12480711-Protein-Serine-Threonine Kinases, pubmed-meshheading:12480711-Proto-Oncogene Proteins, pubmed-meshheading:12480711-Proto-Oncogene Proteins c-akt, pubmed-meshheading:12480711-Radiation-Protective Agents, pubmed-meshheading:12480711-Recombinant Proteins, pubmed-meshheading:12480711-Serum Albumin, pubmed-meshheading:12480711-Signal Transduction, pubmed-meshheading:12480711-Tumor Cells, Cultured
pubmed:year
2003
pubmed:articleTitle
Albumin activates the AKT signaling pathway and protects B-chronic lymphocytic leukemia cells from chlorambucil- and radiation-induced apoptosis.
pubmed:affiliation
Department of Hematology, Royal Free and University College Medical School, London, United Kingdom.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't