Fig. 3: DAC incorporation and relative DNA methylation in PB and BM MNCs across treatment phases.
From: Clinical response to azacitidine in MDS is associated with distinct DNA methylation changes in HSPCs
a Administration of azacitidine (5-AZA-C), in vivo modification, and DNA incorporation leading to DNMT1 degradation and DNA hypomethylation. Drug incorporation into DNA is assessed by measuring NaBH4-stabilised and fragmented DNA (dihydro 5-AZA-dC ribonucleotide (R)) by mass spectrometry. Schematic partially created in BioRender. Thoms, J. (2025) https://BioRender.com/6ep5ch6. b, c Drug incorporation and DNA methylation (relative to baseline) during injection phase (n = 26, responder: 16, non-responder: 10]). b Drug incorporation in responders and non-responders at all sample points (left) or separated by cycle day (right). Statistical comparisons for b–g were performed using a two-sided linear mixed model approach with subject-level random effects to account for within-subject variability, significant P values are as indicated, ns indicates P > 0.05. Boxplots throughout this figure show centre = median, box = interquartile range (IQR), whiskers = furthest point within 1.5xIQR, outliers = points >1.5xIQR. c Relative DNA methylation at all sample points or separated by cycle day. d, e Drug incorporation and DNA methylation during the injection and oral phases of the study (injection: n = 29, oral: n = 19) (d) DAC incorporation during the injection and oral phase at all sample points (left) or separated by cycle day (right). e Relative DNA methylation at all sample points or separated by cycle day. f, g Drug incorporation and DNA methylation during oral phase of the study (n = 19, responder: 8, non-responder: 11). f DAC incorporation in responders and non-responders at all sample points (left) or separated by cycle day (right). g Relative DNA methylation at all sample points or separated by cycle day. (h) Relative DNA methylation in bone marrow (BM) mononuclear cells (MNC) compared to pre-treatment (n = 17, responder: 11, non-responder: 6). Left: aggregate data at each timepoint. Right: Longitudinal methylation changes. Statistical comparisons for (h, j) were performed using two-sided t-test_ind (scipy.stats). i Comparison of methylation changes measured by mass spectrometry or LINE-1 PCR assay in BM MNC. Green—concordant methylation changes in both assays. Purple—methylation changes differ between assays (n = 25). j Relative LINE-1 DNA demethylation in BM CD34+ cells compared to pre-treatment (n = 17, responder: 10, non-responder: 8). Left: aggregate data at each timepoint. Right: Longitudinal methylation changes.
