title: The more basic isoform of eEF1A relates to tumour cell phenotype and is modulated by hyper-proliferative/differentiating stimuli in normal lymphocytes and CCRF-CEM T-lymphoblasts.
abstract: The elongation factor 1A proteins (eEF1A1/A2) are known to play a role in tumours. We previously found that a more basic isoform of eEF1A (MBI-eEF1A) is present in the cytoskeletal/nuclear-enriched extracts of CCRF-CEM T-lymphoblasts but not in those of normal lymphocytes. To obtain deeper knowledge about MBI-eEF1A biology, we investigate from which of the eEF1A proteins, eEF1A1 or eEF1A2, MBI-eEF1A originates and the possibility that its appearance can be modulated by the differentiated or proliferative cell status. CCRF-CEM T-lymphoblasts and normal lymphocytes were cultured with or without differentiation/pro-proliferative stimuli (Phorbol 12-Myristate 13-Acetate (PMA) alone or the combination of phytohaemagglutinin (PHA) with PMA, respectively), and the presence of MBI-eEF1A evaluated together with that of the eEF1A1/A2 mRNAs. Our data indicate that the MBI-eEF1A may derive from eEF1A1 as eEF1A2 is not expressed in CCRF-CEM and normal lymphocytes. Moreover, MBI-eEF1A is inducible in normal lymphocytes upon hyper-proliferative stimuli application; in CCRF-CEM, its presence can be abrogated by PMA-induced differentiation. Finally, MBI-eEF1A may have a functional role in hyper-proliferating/tumour cells as its disappearance reduces the growth of CCRF-CEM and that of PHA/PMA-stimulated lymphocytes. The presented data suggest that MBI-eEF1A may be related to oncogenic cell phenotype, rising the possibility to use MBI-eEF1A as target for novel therapeutic strategies.
authors.affiliation: Department of Life Sciences, University of Trieste, Trieste, Italy. bscaggiante@units.it
authors.forename: Bruna
authors.initials: B
authors.lastname: Scaggiante
authors.forename: Barbara
authors.initials: B
authors.lastname: Dapas
authors.forename: Gabriele
authors.initials: G
authors.lastname: Pozzato
authors.forename: Gabriele
authors.initials: G
authors.lastname: Grassi
mesh_terms: D002454:Cell Differentiation / Q000187:drug effects / Q000502:physiology; D048708:Cell Growth Processes / Q000187:drug effects / Q000502:physiology; D045744:Cell Line, Tumor; D006801:Humans; D019169:Jurkat Cells; D008214:Lymphocytes / Q000187:drug effects / Q000378:metabolism*; D020648:Peptide Elongation Factor 1 / Q000235:genetics / Q000378:metabolism*; D010641:Phenotype; D010835:Phytohemagglutinins / Q000494:pharmacology; D020033:Protein Isoforms; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D013440:Sulfides; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
chemical_list: C094814:EEF1A1 protein, human; D020648:Peptide Elongation Factor 1; D010835:Phytohemagglutinins; D020033:Protein Isoforms; D012333:RNA, Messenger; D013440:Sulfides; C064671:2-chloroethyl methyl sulfide; D013755:Tetradecanoylphorbol Acetate