Abnormal megakaryopoiesis in acute leukaemia

Investigation of Biomarkers Associated with Low Platelet Counts in Normal Karyotype Acute Myeloid Leukemia

Acute myeloid leukemia (AML) patients are at risk of bleeding due to disease-related lack of platelets and systemic coagulopathy. Platelets play a role in hemostasis. Leukemic blasts have been shown to alter platelet activation in vitro. Here we investigated biomarkers associated with thrombocytopenia in normal karyotype AML (NK-AML). From The Cancer Genome Atlas database, case-control study was performed between normal karyotype (NK) platelet-decreased AML (PD-AML, platelet count < 100 × 109/L, n = 24) and NK platelet-not-decreased AML (PND-AML, with platelet count ≥ 100 × 109/L, n = 13). Differentially expressed gene analysis, pathway analysis and modelling for predicting platelet decrease in AML were performed. DEG analysis and pathway analysis revealed 157 genes and eight pathways specific for PD-AML, respectively. Most of the eight pathways were significantly involved in G-protein-coupled receptor-related pathway, cytokine-related pathway, and bone remodeling pathway. Among the key genes involved in at least one pathway, three genes including CSF1R, TNFSF15 and CLEC10A were selected as promising biomarkers for predicting PD-AML (0.847 of AUC in support vector machine model). This is the first study that identified biomarkers using RNA expression data analysis and could help understand the pathophysiology in AML with low platelet count.

Apparent duplication of inv(3)(q21q26) in one of five cases with inv (3) in myelodysplastic syndromes and acute leukemia

Rearrangements affecting the long arm of chromosome 3 have been linked to abnormalities of platelet production and morphology in hematologic disorders. We present five patients with myelodysplastic syndromes or acute leukemia in whom inv(3)(q21q26) was seen. One of the patients showed an inversion of both homologs involving precisely the same breakpoints, suggesting apparent duplication of the abnormal chromosome 3 and loss of the normal homolog. To our knowledge this is the first report detailing such a condition.