Molecular Evaluation of CEBPA Gene Mutation in Normal Karyotype Acute Myeloid Leukemia: A Comparison of Two Methods and Report of Novel CEBPA Mutations from Indian Acute Myeloid Leukemia Patients

摘要

Background and Aim: Mutation in the CAAT/enhancer binding protein-a (CEBPA) gene has been reported as being one of the common genetic abnormalities in acute myeloid leukemia (AML) and is associated with a good clinical outcome. We intend to explore the prevalence of CEBPA mutations and evaluate the efficacy of fragment and sequencing analysis methods for CEBPA mutation detection in Indian AML patients. Materials and Methods: The coding region of the CEBPA gene was screened in 36 normal karyotype AML patients by fragment analysis and direct sequencing. Results: We identified five CEBPA sequence variations in three patient samples (8.3%) by direct sequencing analysis, of which three were novel mutations. These mutations were clustered mostly in the TAD1 and basic region leucine zipper region of the CEBPA protein. Six cases demonstrated a previously reported polymorphism. Two of the three positive cases showed double mutations, and one case had a single mutation. All five mutations were also detected by fragment analysis, indicating a sensitivity of 100% (5/5). No correlation with clinical parameters including age, sex, white blood cell count, hemoglobin, and platelet count between patients with and without mutation was observed. Interestingly, CEBPA mutations were significantly higher in patients with WTI mutation, while no correlation with FLT3 and NPM1 was observed. Conclusion: We report for the first time the frequency of CEBPA mutation from an Indian patients (8.3%). The identification of novel CEBPA mutations added new insights into the genetic heterogeneity of AML. Our result suggests that the optimal approach for detecting CEBPA mutations in AML can be a combination of fragment analysis and direct sequencing.