title: p53 flow cytometry evaluation in leukemias: correlation to factors affecting clinical outcome.
abstract: p53 is a cell cycle checkpoint control protein that assesses DNA damage and acts as a transcription factor regulating genes, which control cell growth, DNA repair, and apoptosis. p53 mutations have been found in a wide variety of different cancers including flow cytometric assessment of p53 protein expression using anti-p53 monoclonal antibodies. We studied p53 protein expression by flow cytometry (FC) assay in 223 blood and/or bone marrow samples from 72 patients with chronic myeloid leukemia (CML): 54 in chronic phase (CML-CP), 7 in accelerated phase (CML-AP), and 11 in blastic phase (CML-BP); 64 patients with chronic lymphoid leukemia (CLL): (34 at diagnosis, 21 in previously treated, and 9 with Richter's syndrome); 44 patients with acute lymphoid leukemia (ALL): 36 at diagnosis and 8 in relapse; and 43 acute myeloid leukemia (AML): 27 de novo, 7 in relapse, and 9 secondary. p53 protein expression was observed in 64 of 223 patient's samples: 14/64 (21.9%) CLL, 13/44 (29.5%) ALL, 19/43 (44.2%) AML, and 17/72 (23.6%) CML. Highest levels were detected in the advanced phases of CLL, ALL, and CML. In addition, in patients with AML, high levels of p53 expression were detected in secondary and relapse disease and also in de novo AML cases. Our results demonstrated that p53 expression levels are strongly associated with advanced disease. On the basis of these results, we concluded that FC can be a reliable approach to study p53 protein expression in leukemic patients.
authors.affiliation: Laboratório de Hemato-Oncologia Celular e Molecular, Hospital do Câncer I, Instituto Nacional de Câncer, Rio de Janeiro - RJ, Brazil. gbcjunior@hotmail.com
authors.forename: Geraldo Barroso
authors.initials: GB
authors.lastname: Cavalcanti
authors.forename: Marcos Antonio Mauricio
authors.initials: MA
authors.lastname: Scheiner
authors.forename: Eliane Pereira
authors.initials: EP
authors.lastname: Simões Magluta
authors.forename: Flavia da Cunha
authors.initials: FC
authors.lastname: Vasconcelos
authors.forename: Claudete Esteves
authors.initials: CE
authors.lastname: Klumb
authors.forename: Raquel Ciuvalschi
authors.initials: RC
authors.lastname: Maia
mesh_terms: D045744:Cell Line, Tumor; D005434:Flow Cytometry / Q000379:methods*; D006262:Health; D006801:Humans; D007938:Leukemia / Q000145:classification / Q000175:diagnosis / Q000378:metabolism* / Q000628:therapy*; D007963:Leukocytes, Mononuclear / Q000378:metabolism; D011379:Prognosis; D016896:Treatment Outcome; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism*
chemical_list: D016159:Tumor Suppressor Protein p53