[Analysis of Genomic Landscape in Patients with Acute Myeloid Leukemia]

To investigate the gene mutation occurved in AML patients with 29 kinds of fusion genes and 51 kinds of tumor gene.

Next-generation sequencing (NGS) was used to detected the 49 kinds of targeted gene. FLT3 internal tandem duplication (FLT3-ITD), CALR, NPM1 and CEBPA mutation were detected by DNA-based PCR and Sanger sequencing. Twenty-nine kinds of fusion genes were dected by multiplex nested RT-PCR.

The total gene mutation rate was 91% (109/121) in all the 121 patients. On average, 2.1 mutated genes per patient were identified, among these 121 patients, coexistence of ≥ 3 mutations was frequent (34.7%). The most commonly mutated genes were NRAS (23.96%, n=29), followed by NPM1 (14.04%, n=17), CEBPA double mutations (14.04%, n=17), KRAS (11.57%, n=14)，FLT3-ITD (10.74%, n=13), CSF3R (10.74%, n=13), TET2 (9.92%, n=12) and IDH1 (9.1%, n=11). Overall, fusion genes were detected in 47 (37.3%) patients, including AML/ETO (n=12), CBFβ/MYH11 (n=11), PML/RARa (n=12), MLL rearranagement realated mutation MLL-X (n=10). TLS/ERG (n=1) and DEK/CAN (n=1) in an order of decreasing frequency. Patients with normal karyotype (NK)- AML exhibited more mutations in CEBPA, NPM1, TET2, RUNX1 and IDH1, comparing with abnormal karyotype patients. KRAS mutation in abnormal kayotype patients was significantly higher than that in normal kayotype patients (P=0.014). TP53 mutations were predominantly associated with complex cytogenetics (P=0.199). KRAS mutations were more frequent in core binding factor (CBF) acute myeloid leukemia (AML) and 11q23/MLL rearrangement leukemia, compared with NK-AML (P=0.006 and 0.003, respectively). KIT mutations predominated in CBF-AML (P=0.006). JAK2V617F mutations were detected in two patients and co-occurred with AML-ETO fusions.

At least one mutation is observed in more than 90% patients. On average, more than 2 mutated genes per patient are identified. Some gene mutations are associated with gene rearrangement.