title: Tumor associated antigen PRAME is a marker of favorable prognosis in childhood acute myeloid leukemia patients and modifies the expression of S100A4, Hsp 27, p21, IL-8 and IGFBP-2 in vitro and in vivo.
abstract: Preferentially expressed antigen of melanoma (PRAME) is expressed in a wide variety of tumors, but in contrast with most other tumor associated antigens, it is also expressed in leukemias. In a previous study, we showed that overexpression of PRAME induced apoptosis, inhibited cell proliferation and reduced tumorigenicity of leukemic cells in vivo. We also demonstrated that PRAME overexpression induced the repression of three genes (Hsp27, S100A4 and p21) associated with an unfavorable prognosis in leukemia. Here, we further investigated the mechanisms of PRAME-induced tumor suppression in vitro and in vivo. We performed a gene profiling study by analysing PRAME shRNA-silenced leukemic cells on high-density micro-arrays (Affymetrix) and found that PRAME altered the expression of two additional genes potentially involved in cancerogenesis and cancer progression: IL-8 and IGFBP-2. In a series of 28 acute myeloid leukemia pediatric patients, we observed that PRAME expression was associated with an increased leukemia-free survival. Importantly, the correlation between PRAME expression in leukemic cell lines and the decreased expression of Hsp27, S100A4, p21, IL-8 and the increased expression of IGFBP-2 was also observed in vivo, in leukemic patients. Our results suggest that the favorable prognosis of PRAME could be mediated, at least in part, by the modified expression of those genes.
authors.affiliation: Laboratory of Cell Physiology, Université Catholique de Louvain, Brussels, Belgium.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Tajeddine
authors.forename: Magali
authors.initials: M
authors.lastname: Louis
authors.forename: Christiane
authors.initials: C
authors.lastname: Vermylen
authors.forename: Jean-Luc
authors.initials: JL
authors.lastname: Gala
authors.forename: Bertrand
authors.initials: B
authors.lastname: Tombal
authors.forename: Philippe
authors.initials: P
authors.lastname: Gailly
mesh_terms: D000951:Antigens, Neoplasm / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D014408:Biomarkers, Tumor / Q000235:genetics / Q000378:metabolism*; D002648:Child; D050759:Cyclin-Dependent Kinase Inhibitor p21 / Q000235:genetics / Q000378:metabolism*; D020869:Gene Expression Profiling; D055551:HSP27 Heat-Shock Proteins; D006360:Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D066298:In Vitro Techniques; D018971:Insulin-Like Growth Factor Binding Protein 2 / Q000235:genetics / Q000378:metabolism*; D016209:Interleukin-8 / Q000235:genetics / Q000378:metabolism*; D015470:Leukemia, Myeloid, Acute / Q000235:genetics / Q000378:metabolism*; D018832:Molecular Chaperones; D009363:Neoplasm Proteins / Q000235:genetics / Q000378:metabolism*; D020411:Oligonucleotide Array Sequence Analysis; D011379:Prognosis; D034741:RNA, Small Interfering / Q000494:pharmacology; D000071999:S100 Calcium-Binding Protein A4; D009418:S100 Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: D000951:Antigens, Neoplasm; D014408:Biomarkers, Tumor; C493956:CDKN1A protein, human; D050759:Cyclin-Dependent Kinase Inhibitor p21; D055551:HSP27 Heat-Shock Proteins; C057725:HSPB1 protein, human; D006360:Heat-Shock Proteins; D018971:Insulin-Like Growth Factor Binding Protein 2; D016209:Interleukin-8; D018832:Molecular Chaperones; D009363:Neoplasm Proteins; C404944:PRAME protein, human; D034741:RNA, Small Interfering; D000071999:S100 Calcium-Binding Protein A4; D009418:S100 Proteins; C077591:S100A4 protein, human