title: Comparative proteomic analysis of all-trans-retinoic acid treatment reveals systematic posttranscriptional control mechanisms in acute promyelocytic leukemia.
abstract: All-trans-retinoic acid (ATRA) induces growth inhibition, differentiation, and apoptosis in cancer cells, including acute promyelocytic leukemia (APL). In APL, expression of promyelocytic leukemia protein retinoic acid receptor-alpha (PML-RARalpha) fusion protein, owing to the t(15; 17) reciprocal translocation, leads to a block in the promyelocytic stage of differentiation. Here, we studied molecular mechanisms involved in ATRA-induced growth inhibition and myeloid cell differentiation in APL. By employing comprehensive high-throughput proteomic methods of 2-dimensional (2-D) gel electrophoresis and amino acid-coded mass tagging coupled with electrospray ionization (ESI) mass spectrometry, we systematically identified a total of 59 differentially expressed proteins that were consistently modulated in response to ATRA treatment. The data revealed significant down-regulation of eukaryotic initiation and elongation factors, initiation factor 2 (IF2), eukaryotic initiation factor 4AI (eIF4AI), eIF4G, eIF5, eIF6, eukaryotic elongation factor 1A-1 (eEF1A-1), EF-1-delta, eEF1gamma, 14-3-3epsilon, and 14-3-3zeta/delta (P <.05). The translational inhibitor DAP5/p97/NAT1 (death-associated protein 5) and PML isoform-1 were found to be up-regulated (P <.05). Additionally, the down-regulation of heterogeneous nuclear ribonucleoproteins (hnRNPs) C1/C2, UP2, K, and F; small nuclear RNPs (snRNPs) D3 and E; nucleoprotein tumor potentiating region (TPR); and protein phosphatase 2A (PP2A) were found (P <.05); these were found to function in pre-mRNA processing, splicing, and export events. Importantly, these proteomic findings were validated by Western blot analysis. Our data in comparison with previous cDNA microarray studies and our reverse transcription-polymerase chain reaction (RT-PCR) experiments demonstrate that broad networks of posttranscriptional suppressive pathways are activated during ATRA-induced growth inhibition processes in APL.
authors.affiliation: BN-2, Biosciences Division, MS M888, Los Alamos National Laboratory, Los Alamos, NM 87545, USA.
authors.forename: Michael N
authors.initials: MN
authors.lastname: Harris
authors.forename: Bulent
authors.initials: B
authors.lastname: Ozpolat
authors.forename: Fadi
authors.initials: F
authors.lastname: Abdi
authors.forename: Sheng
authors.initials: S
authors.lastname: Gu
authors.forename: Allison
authors.initials: A
authors.lastname: Legler
authors.forename: Kwasi G
authors.initials: KG
authors.lastname: Mawuenyega
authors.forename: Maribel
authors.initials: M
authors.lastname: Tirado-Gomez
authors.forename: Gabriel
authors.initials: G
authors.lastname: Lopez-Berestein
authors.forename: Xian
authors.initials: X
authors.lastname: Chen
mesh_terms: D000970:Antineoplastic Agents / Q000494:pharmacology*; D002454:Cell Differentiation / Q000187:drug effects; D045744:Cell Line, Tumor; D015180:Electrophoresis, Gel, Two-Dimensional / Q000592:standards; D034441:Heterogeneous-Nuclear Ribonucleoproteins / Q000032:analysis / Q000235:genetics; D006801:Humans; D015473:Leukemia, Promyelocytic, Acute; D010445:Peptide Elongation Factors / Q000032:analysis / Q000235:genetics; D010448:Peptide Initiation Factors / Q000032:analysis / Q000235:genetics; D040901:Proteomics / Q000379:methods* / Q000592:standards; D012323:RNA Processing, Post-Transcriptional / Q000187:drug effects / Q000502:physiology*; D015203:Reproducibility of Results; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014212:Tretinoin / Q000494:pharmacology*
chemical_list: D000970:Antineoplastic Agents; D034441:Heterogeneous-Nuclear Ribonucleoproteins; D010445:Peptide Elongation Factors; D010448:Peptide Initiation Factors; D014212:Tretinoin