ABSTRACT
BACKGROUND: The epigenetic regulator additional sex combs-like 1 (ASXL1) is an adverse prognostic factor in acute myeloid leukemia (AML). However, the mutational spectrum and prognostic factors of ASXL1-mutated (ASXL1+) AML are largely unknown. We aim to evaluate the risk factors influencing the prognosis of ASXL1+ AML. METHODS: We performed next-generation sequencing (NGS) in 1047 cases of de novo AML and discovered 91 ASXL1+ AML (8.7%). The Log-Rank test and Kaplan-Meier were used to evaluate survival rate, and the Cox regression model was used to analyze multivariate analysis. RESULTS: In a total of 91 ASXL1+ AML, 86% had one or more co-mutations. The factors that had adverse impact on overall survival (OS) and event-free survival (EFS) are defined as high risk factors, including age ≥ 60 years, WBC count ≥ 50 × 109/L, FLT3-ITD mutations, RUNX1 mutations, and absence of AML1-ETO fusion gene. ASXL1 mutations without any risk factor were classified as single-hit ASXL1+ AML; ASXL1 mutations accompanied with one of the risk factors was referred to as double-hit ASXL1+ AML; ASXL1 mutations with two or more of the risk factors were designated as triple-hit ASXL1+ AML. The combination of these risk factors had a negative influence on the prognosis of ASXL1+ AML. The median OS was not attained in single-hit ASXL1+ AML, 29.53 months in double-hit ASXL1+ AML, and 6.67 months in triple-hit ASXL1+ AML (P = 0.003). The median EFS was not attained in single-hit ASXL1+ AML, 29.53 months in double-hit ASXL1+ AML, and 5.47 months in triple-hit ASXL1+ AML (P = 0.002). Allogenic hematopoietic stem cell transplantation (allo-HSCT) improved the prognosis of double/triple-hit ASXL1+ AML patients. CONCLUSIONS: Our study provided new insights into the mutational spectrum and prognostic factors of ASXL1+ AML patients. Our primary data suggest that the risk factors in ASXL1+ AML contribute to the poor outcome of these patients. The management of ASXL1+ AML patients should be based on the risk factors and allo-HSCT is highly recommended for consolidation.
ABSTRACT
OBJECTIVE: To analyze the characteristics of gene mutation in adult ALL and its clinical significance. METHODS: Clinical data of 134 primary adult ALL patients and DNA sequencing results of 16 kinds of gene mutation were collected. The characteristic of gene mutation and clinical significances were statistically analyzed. RESULTS: In 31 cases of 134 ALL cases (23.13%) the gene mutations were detected as follows: 19 cases of 114 B-ALL cases (16.67%), 11 cases of 19 T-ALL cases (57.89%) and 1 case of T/B-ALL. The incidence of T-ALL gene mutation was significantly higher than that of B-ALL (χ2=13.574, P<0.01). Twelve gene mutations were found, and the mutation rates was IL7R, NOTCH1, FLT3, TP53, FBXW7, PAX5, IKZF1, CREBBP, JAK3, JAK1, PHF6 and PTEN from high to low. Among 108 non-transplantable follow-up patients there was no significant difference in 1-year overall survival rate (49.7% vs 67.4%) and median non-recurrence survival time (214 days vs 260 days) between the gene mutation group (23 cases, 21.30%) and the non-mutation group(85 cases, 78.70%). There was a significant difference in 1-year survival rate between NOTCH1 mutation group (4 cases, 3.77%) and non-mutation group (102 cases, 96.23%) (50.0% vs 65.8%,χ2=9.840, P<0.01). CONCLUSION: There may be multiple gene mutations in adult ALL patients. IL7R and NOTCH1 are the most common gene mutations and NOTCH1 mutation may indicate poor prognosis. Detection of gene mutations is helpful to understand the pathogenesis of ALL and evaluate the prognosis of adult ALL patients.
Subject(s)
Precursor Cell Lymphoblastic Leukemia-Lymphoma , Precursor T-Cell Lymphoblastic Leukemia-Lymphoma , Adult , Humans , Mutation , Precursor Cell Lymphoblastic Leukemia-Lymphoma/genetics , Prognosis , Receptor, Notch1/genetics , Sequence Analysis, DNAABSTRACT
OBJECTIVE: To investigate the clinical features, accompanying gene mutation characteristics and prognostic factors of adult patients with acute myeloid leukemia with mutated NPM1 (NPM1+AML). METHODS: Seventy-three patients with newly diagnosed adult NPM1+AML were selected. The mutations of 22 genes were detected by second generation sequencing and 43 fusion genes of AML were detected by real-time fluorescent quantitative PCR. The Kaplan-Meier survival curve and Cox multivariate regression analysis were used to study the prognostic factors. RESULTS: A total of 74 NPM1 site mutations were detected in 73 patients with NPM1+AML. The incidence rates were 92.0% L287fs, 2.7% Q289fs and W288fs, 1.4% L258fs and Q289H, among which 1 patient had 2 NPM1 mutations; the different mutation sites had no effect on the prognosis of NPM1+AML. The median value of NPM1 variant allele frequency (VAF) was 35.4% (1.8%-56.6%). Based on the uppermost quartile of 38.4%, the patients were classified as NPM1 VAF>38.4% (NPM1highAML) and NPM1 VAF≤38.4% (NPM1lowAML). Compared with NPM1lowAML, the early mortality rate was statistically significantly higher (33.3% vs 7.3%, P<0.05), and median EFS (148 dï¼95%CI 58-238 d vs 372 dï¼95%CI 264-480 d) (P<0.01) and median OS (179 d 95%CI 6-352 d vs 444 d) (P<0.01) were significantly shorter in NPM1high AML. A total of 126 accompanying gene mutation sites were detected in 87.7% of patients with NPM1+AML. The patients with NRAS gene mutation displayed a higher rate of complete remission (100% vs 58%) (P<0.05) and longer median OS (not reached to 320 d, 95%CI 150-490 d) (P<0.05). The 43 fusion genes were examined in 65 out of 73 cases of NPM1+AML, and in all the patients the fusion gene test was negative. Multivariate analysis showed that NPM1 VAF>38.4% was an independent prognostic factor for EFS (HR=3.1, 95% CI 1.6-6.4, P<0.01) and OS (HR=3.0, 95% CI 1.4-6.2, P<0.01). CONCLUSION: The NPM1 gene mutation in AML patients often is accompanied by other gene mutations, while the coexistence of fusion genes is rare; high NPM1 mutant allele burden is an independent prognostic factor for adult AML patients with mutated NPM1.