Survey of activated FLT3 signaling in leukemia

• Published in: PloS one 2011-04, Vol.6 (4), p.e19169-e19169
• Main Authors: Gu, Ting-lei, Nardone, Julie, Wang, Yi, Loriaux, Marc, Villén, Judit, Beausoleil, Sean, Tucker, Meghan, Kornhauser, Jon, Ren, Jianmin, MacNeill, Joan, Gygi, Steven P, Druker, Brian J, Heinrich, Michael C, Rush, John, Polakiewicz, Roberto D
• Format: Article
• Language: English
• Subjects: Accuracy; Acute lymphoblastic leukemia; Acute myeloid leukemia; Amino acids; B cells; Biotechnology; Bone marrow; Bone Marrow Cells - drug effects; Bone Marrow Cells - metabolism; CD40 antigen; Cell culture; Cell Line, Tumor; Cytotoxicity; fms-Like Tyrosine Kinase 3 - genetics; fms-Like Tyrosine Kinase 3 - metabolism; Gene expression; Genetic transformation; Hematology; Humans; In vivo methods and tests; Isotopes; Kinases; Leukemia; Leukemia, Myeloid, Acute - pathology; Localization; Lymphatic leukemia; Lymphocytes B; Medical research; Medicine; Metastasis; Molecular modelling; Mutation; Myeloid leukemia; Pathogenesis; Phosphoamino Acids - metabolism; Phosphorylation; Phosphorylation - drug effects; Piperazines - pharmacology; Precursor Cell Lymphoblastic Leukemia-Lymphoma - pathology; Prostate cancer; Protein-tyrosine kinase; Proteins; Proteomics; Quinazolines - pharmacology; Serine; Signal transduction; Signal Transduction - drug effects; Signaling; Surveys; Threonine; Transformation; Tumor cell lines; Tyrosine
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0019169

Activating mutations of FMS-like tyrosine kinase-3 (FLT3) are found in approximately 30% of patients with acute myeloid leukemia (AML). FLT3 is therefore an attractive drug target. However, the molecular mechanisms by which FLT3 mutations lead to cell transformation in AML remain unclear. To develop a better understanding of FLT3 signaling as well as its downstream effectors, we performed detailed phosphoproteomic analysis of FLT3 signaling in human leukemia cells. We identified over 1000 tyrosine phosphorylation sites from about 750 proteins in both AML (wild type and mutant FLT3) and B cell acute lymphoblastic leukemia (normal and amplification of FLT3) cell lines. Furthermore, using stable isotope labeling by amino acids in cell culture (SILAC), we were able to quantified over 400 phosphorylation sites (pTyr, pSer, and pThr) that were responsive to FLT3 inhibition in FLT3 driven human leukemia cell lines. We also extended this phosphoproteomic analysis on bone marrow from primary AML patient samples, and identify over 200 tyrosine and 800 serine/threonine phosphorylation sites in vivo. This study showed that oncogenic FLT3 regulates proteins involving diverse cellular processes and affects multiple signaling pathways in human leukemia that we previously appreciated, such as Fc epsilon RI-mediated signaling, BCR, and CD40 signaling pathways. It provides a valuable resource for investigation of oncogenic FLT3 signaling in human leukemia.