title: Expression of Ik6 and Ik8 Isoforms and Their Association with Relapse and Death in Mexican Children with Acute Lymphoblastic Leukemia.
abstract: Expression of the 6 and 8 dominant-negative Ikaros isoforms in pediatric patients with acute lymphoblastic leukemia has been associated with a high risk of relapse and death; due to these isoforms disrupting the differentiation and proliferation of lymphoid cells. The aim of this study was to know the frequency of Ik6 and Ik8 in 113 Mexican ALL-children treated within the National Popular Medical Insurance Program to determine whether there was an association with relapse-free survival, event-free survival and overall survival, and to assess its usefulness in the initial stratification of patients. The expression of these isoforms was analyzed using specific primer sets and nested RT-PCR. The detected transcripts were classified according to the isoforms's sizes reported. A non-expected band of 300 bp from one patient was analyzed by sequencing. Twenty-six patients expressed Ik6 and/or Ik8 and one of them expressed a variant of Ik8 denominated Ik8-deleted. Although the presence of them was not statistically associated with lower relapse free survival (p = 0.432), event free survival (p = 0.667) or overall survival (p = 0.531), inferior overall survival was observed in patients that expressed these isoforms and showed high or standard risk by age and white blood-cell count at diagnosis. Of the 26 patients Ik6+ and/or Ik8+, 14 did not present adverse events; from them 6 were exclusively Ik6+ and/or Ik8+, and 8 were positive for the other Ikaros isoforms (Ik1, Ik2, Ik5, Ik3A, Ik4, Ik4A, Ik7). In the patients studied, the expression of Ik6 and Ik8 did not constitute an independent prognostic factor for relapse or death related to disease; therefore, they could not be used in the initial risk stratification.
authors.affiliation: Laboratorio de Cultivo de Tejidos, Departamento de Genética Humana, Instituto Nacional de Pediatría, México, DF, México.
authors.forename: Adriana
authors.initials: A
authors.lastname: Reyes-León
authors.affiliation: Laboratorio de Cultivo de Tejidos, Departamento de Genética Humana, Instituto Nacional de Pediatría, México, DF, México.
authors.forename: Rocío
authors.initials: R
authors.lastname: Juárez-Velázquez
authors.affiliation: Laboratorio de Cultivo de Tejidos, Departamento de Genética Humana, Instituto Nacional de Pediatría, México, DF, México.
authors.forename: Alma
authors.initials: A
authors.lastname: Medrano-Hernández
authors.affiliation: Laboratorio de Cultivo de Tejidos, Departamento de Genética Humana, Instituto Nacional de Pediatría, México, DF, México.
authors.forename: Teresa
authors.initials: T
authors.lastname: Cuenca-Roldán
authors.affiliation: Laboratorio de Cultivo de Tejidos, Departamento de Genética Humana, Instituto Nacional de Pediatría, México, DF, México.
authors.forename: Consuelo
authors.initials: C
authors.lastname: Salas-Labadía
authors.affiliation: Laboratorio de Cultivo de Tejidos, Departamento de Genética Humana, Instituto Nacional de Pediatría, México, DF, México.
authors.forename: María
authors.initials: M
authors.lastname: Del Pilar Navarrete-Meneses
authors.affiliation: Subdirección de Hemato-Oncología, Instituto Nacional de Pediatría, México, DF, México.
authors.forename: Roberto
authors.initials: R
authors.lastname: Rivera-Luna
authors.affiliation: Hospital para el Niño Poblano, Puebla, México.
authors.forename: Gerardo
authors.initials: G
authors.lastname: López-Hernández
authors.affiliation: Servicio de Hematología, Instituto Nacional de Pediatría, México, DF, México.
authors.forename: Rogelio
authors.initials: R
authors.lastname: Paredes-Aguilera
authors.affiliation: Laboratorio de Cultivo de Tejidos, Departamento de Genética Humana, Instituto Nacional de Pediatría, México, DF, México.
authors.forename: Patricia
authors.initials: P
authors.lastname: Pérez-Vera
mesh_terms: D014408:Biomarkers, Tumor / Q000235:genetics / Q000378:metabolism*; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D051740:Ikaros Transcription Factor / Q000235:genetics / Q000378:metabolism*; D007223:Infant; D008297:Male; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000175:diagnosis* / Q000378:metabolism / Q000401:mortality; D011379:Prognosis; D020033:Protein Isoforms / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D012008:Recurrence
chemical_list: D014408:Biomarkers, Tumor; C497239:IKZF1 protein, human; D020033:Protein Isoforms; D012333:RNA, Messenger; D051740:Ikaros Transcription Factor