title: Mutations of FLT3, NRAS, KRAS, and PTPN11 are frequent and possibly mutually exclusive in high hyperdiploid childhood acute lymphoblastic leukemia.
abstract: Although it has been suggested that mutations of the FLT3, NRAS, KRAS, and PTPN11 genes are particularly frequent in high hyperdiploid (>50 chromosomes) pediatric acute lymphoblastic leukemias (ALLs), this has as yet not been confirmed in a large patient cohort. Furthermore, it is unknown whether mutations of these genes coexist in hyperdiploid cases. We performed mutation analyses of FLT3, NRAS, KRAS, and PTPN11 in a consecutive series of 78 high hyperdiploid ALLs. Twenty-six (33%) of the cases harbored a mutation, comprising six activating point mutations and one internal tandem duplication of FLT3 (7/78 cases; 9.0%), eight codon 12, 13, or 61 NRAS mutations (8/78 cases; 10%), five codon 12 or 13 KRAS mutations (5/78 cases, 6.4%), and seven exon 3 or 13 PTPN11 mutations (7/78 cases; 9.0%). No association was seen between the presence of a mutation in FLT3, NRAS, KRAS, or PTPN11 and gender, age, white blood cell count, or relapse, suggesting that they do not confer a negative prognostic impact. Only one case harbored mutations in two different genes, suggesting that mutations of these four genes are generally mutually exclusive. In total, one third of the cases harbored a FLT3, NRAS, KRAS, or PTPN11 mutation, identifying the RTK-RAS signaling pathway as a potential target for novel therapies of high hyperdiploid pediatric ALLs.
authors.affiliation: Department of Clinical Genetics, University Hospital, Lund, Sweden.
authors.forename: Kajsa
authors.initials: K
authors.lastname: Paulsson
authors.forename: Andrea
authors.initials: A
authors.lastname: Horvat
authors.forename: Bodil
authors.initials: B
authors.lastname: Strömbeck
authors.forename: Fredrik
authors.initials: F
authors.lastname: Nilsson
authors.forename: Jesper
authors.initials: J
authors.lastname: Heldrup
authors.forename: Mikael
authors.initials: M
authors.lastname: Behrendtz
authors.forename: Erik
authors.initials: E
authors.lastname: Forestier
authors.forename: Anna
authors.initials: A
authors.lastname: Andersson
authors.forename: Thoas
authors.initials: T
authors.lastname: Fioretos
authors.forename: Bertil
authors.initials: B
authors.lastname: Johansson
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D004252:DNA Mutational Analysis; D004171:Diploidy; D005260:Female; D011905:Genes, ras; D006801:Humans; D007223:Infant; D008297:Male; D009154:Mutation; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000201:enzymology* / Q000235:genetics*; D054592:Protein Tyrosine Phosphatase, Non-Receptor Type 11 / Q000235:genetics*; D011518:Proto-Oncogene Proteins / Q000235:genetics*; D016283:Proto-Oncogene Proteins p21(ras); D051941:fms-Like Tyrosine Kinase 3 / Q000235:genetics*; D018631:ras Proteins / Q000235:genetics*
chemical_list: C117307:KRAS protein, human; D011518:Proto-Oncogene Proteins; C497970:FLT3 protein, human; D051941:fms-Like Tyrosine Kinase 3; D054592:Protein Tyrosine Phosphatase, Non-Receptor Type 11; D016283:Proto-Oncogene Proteins p21(ras); D018631:ras Proteins