Delineation of Molecular Lesions in Acute Myeloid Leukemia Patients at Diagnosis: Integrated Next Generation Sequencing and Cytogenomic Studies

Interleukin-37 gene expression is down-regulated in patients with acute myeloid leukemia and shown to be affected by CD14 and HLA-DR immunophenotypes

Recent evidence has indicated that interleukin 37 (IL-37) shows down-regulated expression in patients with acute myeloid leukemia (AML), but its association with immunophenotypic markers has not been explored. In the current study, IL37 mRNA expression was analyzed in the peripheral blood of 131 AML patients and 100 controls using the 2-ΔΔCt method (fold change), which was based on the principles of quantitative real-time polymerase chain reaction. AML patients were characterized in terms of gender, therapy, fms-like tyrosine kinase 3/internal tandem duplication (FLT3/ITD) and nucleophosmin 1 (NPM1) mutations, French-American-British classification (FAB), World Health Organization (WHO) classification, and immunophenotypes of 25 cytoplasmic and surface markers. IL37 mRNA expression was given as median and interquartile range. Low expression of IL37 mRNA (0.273 [0.062-0.456]) was found in AML patients. This reduced expression was more pronounced in females than in males but the difference was significant before the Bonferroni correction (0.196 [0.045-0.411] vs. 0.4 [0.153-0.466]; probability [p] = 0.008; corrected p = 0.064). In addition, the FAB M4 type (0.109 [0.031-0.269]) and the WHO PML-RARA type (0.171 [0.061-0.482]) had the lowest expression of IL37 mRNA among the other types. For immunophenotypes, only two significant differences were found. First, CD14-positive patients showed a lower level of expression than CD14-negative patients (0.146 [0.033-0.413] vs. 0.323 [0.108-0.468]; p = 0.02). Second, HLA-DR-positive patients showed a higher level of expression than HLA-DR-negative patients (0.325 [0.163-0.474] vs. 0.214 [0.045-0.42]; p = 0.04). However, the corrected p-value was not significant in both cases (p > 0.05). In conclusion, IL37 mRNA expression was down-regulated in AML patients, especially females, and those with the FAB M4 type and the WHO PML-RARA type. This expression may be affected by the immunophenotypic markers CD14 and HLA-DR.

Targeted Therapy Development in Acute Myeloid Leukemia

Therapeutic developments targeting acute myeloid leukemia (AML) have been in the pipeline for five decades and have recently resulted in the approval of multiple targeted therapies. However, there remains an unmet need for molecular treatments that can deliver long-term remissions and cure for this heterogeneous disease. Previously, a wide range of small molecule drugs were developed to target sub-types of AML, mainly in the relapsed and refractory setting; however, drug resistance has derailed the long-term efficacy of these as monotherapies. Recently, the small molecule venetoclax was introduced in combination with azacitidine, which has improved the response rates and the overall survival in older adults with AML compared to those of chemotherapy. However, this regimen is still limited by cytotoxicity and is not curative. Therefore, there is high demand for therapies that target specific abnormalities in AML while sparing normal cells and eliminating leukemia-initiating cells. Despite this, the urgent need to develop these therapies has been hampered by the complexities of this heterogeneous disease, spurring the development of innovative therapies that target different mechanisms of leukemogenesis. This review comprehensively addresses the development of novel targeted therapies and the translational perspective for acute myeloid leukemia, including the development of selective and non-selective drugs.

The role of next-generation sequencing in acute myeloid leukemia

PURPOSE OF REVIEW

The development of high-throughput techniques like next-generation sequencing (NGS) has unraveled the genetic profile of cancer. In this review, we discuss the role of NGS on the diagnostic, risk stratification, and follow-up of patients with acute myeloid leukemia (AML).

RECENT FINDINGS

NGS has become an essential tool in clinical practice for AML management. Therefore, efforts are being made to improve its applications, automation, and turnaround time. Other high-throughput techniques, such as whole genome sequencing or RNA-sequencing, can be also used to this end. However, not all institutions may be able to implement these approaches. NGS is being investigated for measurable residual disease (MRD) assessment, especially with the development of error-correction NGS. New data analysis approaches like machine learning are being investigated in order to integrate genomic and clinical data and develop comprehensive classifications and risk scores.

SUMMARY

NGS has proven to be a useful approach for the analysis of genomic alterations in patients with AML, which aids patient management. Current research is being directed at reducing turnaround time and simplifying processes so that these techniques can be universally integrated into clinical practice.

Molecular evaluation of gene mutation profiles and copy number variations in pediatric acute myeloid leukemia

BACKGROUND

The objectives of this study were to investigate the mutation profiles of targeted genes and copy number variations (CNVs) in normal cytogenetics (CN) pediatric acute myeloid leukemia (AML).

METHODS

This prospective study was conducted from October 2018 to December 2020. The next-generation sequencing (NGS) and chromosomal microarray analyses (CMA) were performed in pediatric CN-AML patients.

RESULTS

Out of 94 children (aged ≤18 years), 70 patients with AML (24 excluded) underwent conventional karyotyping/cytogenetic analyses. Forty-five (64.3%) of patients had abnormal/ recurrent cytogenetic abnormalities and 25 (35.7%) had normal cytogenetics. Twenty-three out of 25 CN-AML were further processed for gene mutation profile and CNVs using NGS and CMA, respectively. Twenty-two out of 23 (95.7%) patients were detected to have mutations in various genes. The common mutations were: NRAS, NPM1, CEBPA, KRAS, KIT, RUNX1, NOTCH1, WT1, GATA1, GATA2, FLT3, KMT2D, FLT3-TKD, and PHF6. Copy number variations (CNVs) were detected in nine patients (39%), and eight (34.8%) had a long contiguous stretch of homozygosity (LCSH) /loss of heterozygosity (LOH). An LCSH was detected on chromosomes 5, 7, 11, and 19. The gains were more common than losses (8 vs 2). The gains were observed on chromosomes 8, 9, 14, 19, 21, and 22, and the losses were detected on chromosomes 7 and 10. Monosomy was observed in three patients. Three patients (monosomy7, n = 2, and FLT-ITD, n = 1) were reclassified into the high-risk category. Post-induction, complete remission was achieved in all evaluable patients.

CONCLUSION

CN-AML patients have genetic abnormalities that can be detected by more advanced techniques like NGS and CMA. These genetic abnormalities play a role in risk stratification that may remain hidden in otherwise CN-AML.