[Clinical Characteristics of Acute Myeloid Leukemia Patients with RUNX1 Gene Mutation]

To investigate the incidence of Runt-related transcription factor 1 (RUNX1) gene and its associated gene mutations in patients with acute myeloid leukemia (AML), and analyze its clinical characteristics and prognosis.

The genomic DNA-PCR method was used to detect the exon of RUNX1 gene, and the gene mutations were analyzed by genetic sequencing. NPM1, DNMT3A, FLT3-ITD, IDH1/2, K/N-RAS, CEPBA, TET2, and WT1 co-mutations were also detected. Patients were followed up to determine efficacy and prognosis.

Among 171 patients, the RUNX1 gene mutation was detected in 17 cases, and the mutation rate was 9.9%. The type of RUNX1 gene mutation was 9 missense mutations, 4 frameshift mutations, and 4 nonsense mutations. The peripheral blood leukocyte count of the patients in mutation group was 3 (1-101) ×10⁹/L, which was significantly lower than those in the non-mutation group [26 (1-298)×10⁹/L] (P=0.002), while the platelet count was 79 (22-166)×10⁹/L, which was higher than 50 (8-351)×10⁹/L in the non-mutation group (P=0.010), and the proportion of bone marrow blasts of the patients in the mutation group was 37 (0-72)%, which was lower than 53 (0-98)% in the non-mutation group (P=0.020). The RUNX1 mutation rate in M0 type was 55.6%, and in M4 type was 13.6%, which was significantly higher than other FAB subtypes (P=0.003). There was no significant difference in age, sex, hemoglobin concentration, and counts of peripheral blood mononuclear cells (P>0.05). The prognosis of cytogenetics in the patients in the middle and high-risk groups was 88.1% and 89.7%, which were significantly higher than that in the low-risk group, and the difference showed statistically significant (P=0.018). There was no significantly relationship between RUNX1 and specific karyotype abnormalities, including Trisomy 8, Del (7q), t (8; 21), and Inv (16) (P>0.05). There was a significant relationship between RUNX1 gene mutation and IDH1/2, N/K-RAS gene mutation (P<0.01). The complete response rate (CR) of the patients with chemotherapy in the RUNX1 mutation group(37.5%) was significantly lower than 79.4% in the non-mutated group (P=0.001). The overall survival (OS) of the patients in RUNX1 gene mutation group was lower than that in non-mutation group (P<0.05).

AML patients with RUNX1 gene mutation shows unique clinical and biological characteristics, RUNX1 mutation can be regarded as a molecular marker of poor prognosis in AML patients.