Unknown,Transcriptomics,Genomics,Proteomics

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TET2 mutations in acute myeloid leukemia: Results from a comprehensive genetic and clinical analysis of the AML Study Group (AMLSG)

ABSTRACT: Purpose: The tet oncogene family member 2 (TET2) gene was recently identified mutated in myeloid disorders including acute myeloid leukemia (AML). To date, there is increasing evidence for a functional role of TET2 mutations (TET2mut) in AML. Thus, we explored frequency, gene expression pattern, and clinical impact of TET2mut in a large cohort of AML patients, in the context of other AML-associated aberrations. Patients and Methods: Samples from 783 younger adult AML patients were analyzed for the presence of TET2mut (coding exons 3-11), and results were correlated with data from molecular genetic analyses, gene expression profiling, and clinical outcome. Results: In total, 66 TET2mut were found in 60 (60/783; 7.6%) patients, including missense (n=37), frameshift (n=16), and nonsense (n=13) mutations, which with one exception were all heterozygous. TET2mut were not correlated with distinct clinical features or genetic alterations, except for isocitrate dehydrogenase mutations (IDHmut) that were almost mutually exclusive with TET2mut (p<0.001). TET2mut were characterized by only a weak gene expression pattern, which nevertheless reflected TET2mut-associated biology. TET2mut did not impact response to induction therapy and clinical outcome; combining patients exhibiting TET2mut and/or IDHmut revealed shorter overall survival (p=0.03), although this association was not independent from known risk factors. Conclusion: TET2mut were identified in 7.6% of younger adult AML patients and did not impact response to therapy and survival. Mutations were mutually exclusive with IDHmut, thereby supporting recent data on a common mechanism of action, which might obscure the impact of TET2mut if compared against all other AML cases. We performed a supervised class comparison analysis comparing 31 TET-mutated AML cases (TET2 mut) vs. 302 TET2-wildtype AML cases (TET wt) to see if a specific gene expression pattern associated with the presence of the identified TET2 mutations could be determined. No technical replicates were performed.

ORGANISM(S): Homo sapiens

SUBMITTER: Lars Bullinger

PROVIDER: E-GEOD-32246 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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TET2 mutations in acute myeloid leukemia: Results from a comprehensive genetic and clinical analysis of the AML Study Group (AMLSG)

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