title: Mutations of the TET2 and CBL genes: novel molecular markers in myeloid malignancies.
abstract: Despite recent progress in molecular research in myeloid malignancies, in subsets of patients with myelodysplastic syndrome (MDS) so far no underlying mutation was identified. In the myeloproliferative neoplasms (MPNs), the JAK2V617F alone cannot explain the phenotypic heterogeneity. In acute myeloid leukemia (AML), clinical variability exists within distinct subgroups. Thus, the search for novel molecular markers continues. Recently, mutations of the tet oncogene family member 2 (TET2) and Casitas B-cell lymphoma (CBL) genes became the focus of interest. With diverse genetic methods, TET2 on chromosome 4q24 was identified as candidate tumor suppressor gene. Sequencing studies revealed heterogeneous mutations in 10-25% of patients with acute myeloid leukemia (AML), MDS, and MPNs, while the frequency might be higher in chronic myelomonocytic leukemia (CMML). The prognostic impact is being explored. The CBL gene is involved in the degradation of tyrosine kinases. In rare cases of human AML (<2%), CBL mutants were identified, with a higher frequency in core binding factor leukemias. Presence of these mutations was suggested to be involved in aberrant FLT3 expression. In the MPNs, a 2-8% frequency of CBL mutations was reported. These novel mutations deepened insights in the mechanisms of leukemogenesis, might contribute to the identification of new therapeutic targets, and improve diagnostics in the myeloid malignancies.
authors.affiliation: Interdisciplinary Clinic for Stem Cell Transplantation, University Cancer Center Hamburg, Martinistr. 52, 20246 Hamburg, Germany.
authors.forename: Ulrike
authors.initials: U
authors.lastname: Bacher
authors.forename: Claudia
authors.initials: C
authors.lastname: Haferlach
authors.forename: Susanne
authors.initials: S
authors.lastname: Schnittger
authors.forename: Alexander
authors.initials: A
authors.lastname: Kohlmann
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Kern
authors.forename: Torsten
authors.initials: T
authors.lastname: Haferlach
mesh_terms: D014408:Biomarkers, Tumor / Q000235:genetics / Q000378:metabolism*; D002894:Chromosomes, Human, Pair 4 / Q000235:genetics / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D049308:Dioxygenases; D006801:Humans; D015470:Leukemia, Myeloid, Acute / Q000235:genetics / Q000378:metabolism*; D009154:Mutation; D009190:Myelodysplastic Syndromes; D011518:Proto-Oncogene Proteins / Q000235:genetics / Q000378:metabolism*; D050721:Proto-Oncogene Proteins c-cbl / Q000235:genetics / Q000378:metabolism*
chemical_list: D014408:Biomarkers, Tumor; D004268:DNA-Binding Proteins; D011518:Proto-Oncogene Proteins; D049308:Dioxygenases; C541081:TET2 protein, human; D050721:Proto-Oncogene Proteins c-cbl; C067419:CBL protein, human