Auer rods in mixed phenotype acute leukemia, T/myeloid: A report of three cases

The impact of COVID-19 on microRNA and CD marker expression in AML patients

Acute myeloid leukaemia (AML) is an aggressive leukaemia characterised by uncontrolled blast cell proliferation. miRNAs and Clusters of Differentiation (CD) molecules play essential roles in AML progression. This study aims to investigate the effect of COVID-19 on the expression of circulating miRNA and CD molecules in AML. This cross-sectional study recruited 32 AML patients and 20 controls. Blood samples were collected and analysed using molecular cytogenetic, miRNA/mRNA expression, and flow cytometry techniques. The expression of miRNAs varied significantly between patients with AML and control individuals. The co-expression of these miRNAs was higher (P < 0.05), indicating that the presence of one miRNA led to increased expression of other miRNAs. A differential correlation was observed between miRNAs and CD markers. Additionally, miRNA 16, miRNA 21, and miRNA 221 showed significant downregulation (P < 0.05 and P < 0.01, respectively) in AML patients with COVID-19 infection compared to those without a disease. Interestingly, this study identified a higher expression level (P < 0.01) of miRNA 137 as a novel biomarker for AML patients. Moreover, the expression of miRNA 137 showed a high correlation (P < 0.05) with most of the CD markers examined in this study and FISH features data. Furthermore, a strong correlation (P < 0.01) was observed between CD markers and miRNA among AML patients with positive and negative COVID-19 infection. These data demonstrated that COVID-19 contributed to increased expression of microRNAs in AML patients. MicroRNA 137 was identified as a novel microRNA that exhibited significant differences between patients and healthy individuals, highlighting its role in AML pathogenesis.

Broad genomic workup including optical genome mapping uncovers a DDX3X: MLLT10 gene fusion in acute myeloid leukemia

In acute myeloid leukemia (AML), treatment decisions are currently made according to the risk classification of the European LeukemiaNet (ELN), which is based on genetic alterations. Recently, optical genome mapping (OGM) as a novel method proved to yield a genome-wide and detailed cytogenetic characterization at the time of diagnosis. A young female patient suffered from a rather unexpected aggressive disease course under FLT3 targeted therapy in combination with induction chemotherapy. By applying a “next-generation diagnostic workup“ strategy with OGM and whole-exome sequencing (WES), a DDX3X: MLLT10 gene fusion could be detected, otherwise missed by routine diagnostics. Furthermore, several aspects of lineage ambiguity not shown by standard diagnostics were unraveled such as deletions of SUZ12 and ARPP21, as well as T-cell receptor recombination. In summary, the detection of this particular gene fusion DDX3X: MLLT10 in a female AML patient and the findings of lineage ambiguity are potential explanations for the aggressive course of disease. Our study demonstrates that OGM can yield novel clinically significant results, including additional information helpful in disease monitoring and disease biology.