Aberrant Phenotypes in Acute Myeloid Leukemia and Its Relationship with Prognosis and Survival: A Systematic Review and Meta-Analysis

Detection of continuous hierarchical heterogeneity by single-cell surface antigen analysis in the prognosis evaluation of acute myeloid leukaemia

BACKGROUND

Acute myeloid leukaemia (AML) is characterised by the malignant accumulation of myeloid progenitors with a high recurrence rate after chemotherapy. Blasts (leukaemia cells) exhibit a complete myeloid differentiation hierarchy hiding a wide range of temporal information from initial to mature clones, including genesis, phenotypic transformation, and cell fate decisions, which might contribute to relapse in AML patients.

METHODS

Based on the landscape of AML surface antigens generated by mass cytometry (CyTOF), we combined manifold analysis and principal curve-based trajectory inference algorithm to align myelocytes on a single-linear evolution axis by considering their phenotype continuum that correlated with differentiation order. Backtracking the trajectory from mature clusters located automatically at the terminal, we recurred the molecular dynamics during AML progression and confirmed the evolution stage of single cells. We also designed a 'dispersive antigens in neighbouring clusters exhibition (DANCE)' feature selection method to simplify and unify trajectories, which enabled the exploration and comparison of relapse-related traits among 43 paediatric AML bone marrow specimens.

RESULTS

The feasibility of the proposed trajectory analysis method was verified with public datasets. After aligning single cells on the pseudotime axis, primitive clones were recognized precisely from AML blasts, and the expression of the inner molecules before and after drug stimulation was accurately plotted on the trajectory. Applying DANCE to 43 clinical samples with different responses for chemotherapy, we selected 12 antigens as a general panel for myeloblast differentiation performance, and obtain trajectories to those patients. For the trajectories with unified molecular dynamics, CD11c overexpression in the primitive stage indicated a good chemotherapy outcome. Moreover, a later initial peak of stemness heterogeneity tended to be associated with a higher risk of relapse compared with complete remission.

CONCLUSIONS

In this study, pseudotime was generated as a new single-cell feature. Minute differences in temporal traits among samples could be exhibited on a trajectory, thus providing a new strategy for predicting AML relapse and monitoring drug responses over time scale.

A comprehensive analysis of cytogenetics, molecular profile, and survival among pediatric acute myeloid leukemia: a prospective study from a tertiary referral center

BACKGROUND AND AIMS

The objectives of this study were to investigate the cyto-molecular profile and survival of pediatric acute myeloid leukemia (AML).

METHODS

This prospective study was carried out in a tertiary care hospital from October 2018 to December 2020. Karyotype and cytogenetics analyses were done to identify chromosomal aberrations in pediatric AML. The targeted molecular panel utilized the polymerase chain reaction (PCR), reverse transcription-polymerase chain reaction (RT-PCR), and fragment analysis.

RESULTS

A total of 70 patients of AML with aged ≤18 years were enrolled in this study. The cytogenetic analyses revealed abnormal/recurrent cytogenetic abnormalities (CA) in 64.3% of patients and normal cytogenetics (CN) in 35.7% of patients. FAB M2 subtype showed frequent aberrant expression of the CD19 marker. CD7, CD11b, and CD36a were significantly present in the absence of molecular markers. Common chromosomal abnormalities were t(translocation) (8;21) (55%), monosomy/deletion 7 (13%), monosomal karyotype (5%) and complex karyotype (3%). The fusion transcripts RUNX1-RUNX1T1 [t(8;21)] (41%) and CBFB-MYH11 [t(16;16)] (3%) were detected by RT-PCR and FLT3-TKD D835 mutation (1.5%) by allele-specific oligo PCR. Fragment analysis revealed NPM1 (8%) mutation and FLT-ITD (9.5%) mutations. Complete remission was achieved in all evaluable patients. The median follow-up period of our patients was 225 days (IQR 28; 426 days). The median event-free survival (EFS) in all patients was 11.9 months (95% CI, 5-12.6 months). The forty months overall survival probability (pOS) was 58% in all patients.

CONCLUSION

The majority of patients had abnormal/recurrent cytogenetics abnormalities. FAB M2 subtype showed frequent aberrant expression of the CD19. The absence of molecular markers may suggest the presence of CD7, CD11b, and CD36a expression. The overall survival has increased considerably in LMIC.

Correlation Analysis and Prognostic Impacts of Biological Characteristics in Elderly Patients with Acute Myeloid Leukemia

Background

The significant heterogeneity of elderly AML patients’ biological features has caused stratification difficulties and adverse prognosis. This paper did a correlation study between their genetic mutations, clinical features, and prognosis to further stratify them.

Methods

90 newly diagnosed elderly acute myeloid leukemia (AML) patients (aged ≥60 years) who detected genetic mutations by next-generation sequencing (NGS) were enrolled between April 2015 and March 2021 in our medical center.

Results

A total of 29 genetic mutations were identified in 82 patients among 90 cases with a frequency of 91.1%. DNMT3A, BCOR, U2AF1, and BCORL1 mutations were unevenly distributed among different FAB classifications (p < 0.05). DNMT3A, IDH2, NPM1, FLT3-ITD, ASXL1, IDH1, SRSF2, BCOR, NRAS, RUNX1, U2AF1, MPO, and WT1 mutations were distributed differently when an immunophenotype was expressed or not expressed (p<0.05). NPM1 and FLT3-ITD had higher mutation frequencies in patients with normal chromosome karyotypes than abnormal chromosome karyotypes (p<0.001, p=0.005). DNMT3A and NRAS mutations predicted lower CR rates. DNMT3A, TP53, and U2AF1 mutations were related to unfavorable OS. TET2 mutation with CD123+, CD11b+ or CD34- predicted lower CR rate. IDH2+/CD34- predicted lower CR rate. ASXL1+/CD38+ and SRSF2+/CD123- predicted shorter OS.

Conclusion

The study showed specific correlations between elderly AML patients’ genetic mutations and clinical features, some of which may impact prognosis.