Biology subjects

DeZern, A. E.

Publications and source records attributed to DeZern, A. E..

4 recordsLinked to original sources

bioRxiv2025

A PBD-dimer containing antibody drug conjugate targeting CCRL2 for high-risk MDS/AML

Patients with myelodysplastic syndrome (MDS)/acute myeloid leukemia (AML) with high-risk features including TP53 mutations and deletions have poor outcomes due to lack of effective therapies. The atypical chemokine surface receptor C-C motif chemokine receptor-like 2 (CCRL2) is overexpressed in MDS and secondary AML (sAML) compared to healthy hematopoietic cells and we recently found that TP53-mutated MDS/AML and AML with erythroid features express the highest levels of this receptor across MDS/AML subtypes. To illustrate the therapeutic potential of CCRL2 as a therapeutic target, we developed an anti-CCRL2 antibody-drug conjugate (ADC) by conjugating an anti-CCRL2 antibody with the cytotoxic drug pyrrolobenzodiazepine (PBD), which causes DNA double-strand breaks leading to cancer cell death. The anti-CCRL2 ADC demonstrated strong CCRL2-selective cytotoxicity against cell lines derived from MDS/AML patients with TP53 mutations and erythroid features, surpassing the cytotoxic effects observed with gemtuzumab and PBD-conjugated anti-CD33 and anti-CD123 ADCs. It also induced apoptosis and suppressed the clonogenicity of primary MDS/AML bone marrow samples without affecting the survival, differentiation and clonogenicity of healthy hematopoietic stem and progenitor cells. This agent also suppressed the leukemic growth of TP53-mutated MDS/AML cell line xenografts, improving mice survival and decreasing the leukemic burden in patient-derived TP53-mutated MDS/AML xenografts. In conclusion, our study introduces CCRL2 as a potential new therapeutic target in high-risk MDS/AML. Statement of significancePyrrolobenzodiazepine(PBD)-conjugated anti-CCRL2 ADC shows anti-leukemic effect in MDS/AML models including TP53-mutated disease without affecting healthy hematopoietic cells supporting that it is a promising candidate for single-agent or combination therapies in high-risk MDS/AML.

cancer biology↗

bioRxiv2025

Unique epigenomic signatures identify biologically significant subtypes of MDS and predict response to azacitidine

Myelodysplastic syndromes (MDS) are characterized by aberrant DNA methylation, and mutations in epigenetic modifiers are frequently found in these patients. Although DNA methyltransferase inhibitors (DNMTi) are used to treat MDS, response variability remains a challenge in the clinic, with limited predictive markers. Through comprehensive genomic, epigenomic, and transcriptomic analyses, we have gained valuable insights into the intricate interplay between genetic and epigenetic alterations in MDS. We describe aberrantly hyper and hypomethylated regions in MDS, extending beyond promoter regions and affecting long-distance regulatory elements. Using these aberrant DNA methylation patterns, we classified MDS patients into epigenetic subtypes correlated with known molecular drivers. This epigenetic classification includes a novel group of patients characterized only by their shared DNA methylation profile and lacking any genetic drivers. Furthermore, we identified a robust DNA methylation signature capable of distinguishing DNMTi responders from non-responders prior to receiving treatment. Leveraging these DMRs, we developed robust classifiers capable of predictive response to DNMTi by integrating DNA methylation, gene expression, mutations, and laboratory parameters. Our findings highlight the potential of epigenetic-based classifiers for personalized treatment approaches for MDS patients. Key PointsDNA methylation patterns define biologically meaningful MDS subtypes and uncover a new group lacking known mutations. A methylation-based signature at diagnosis predicts azacitidine response, supporting its use in guiding personalized MDS therapy.

cancer biology↗

bioRxiv2025

CCRL2 promotes the interferon-γ signaling response in myeloid neoplasms with erythroid differentiation and mutated TP53

Patients with myeloid neoplasms with loss-of-function TP53 mutations and erythroid differentiation have poor outcomes, and a better understanding of disease biology is required. Upregulation of interferon-{gamma} (IFN-{gamma}) signaling has been associated with acute myeloid leukemia (AML) progression and chemotherapy resistance, but its drivers remain unclear. In this study, we found that the surface receptor C-C motif chemokine receptor-like 2 (CCRL2) is overexpressed in AML with erythroid differentiation and TP53 mutations compared to other AML subtypes and healthy hematopoietic cells. The knockout (KO) of CCRL2 suppressed erythroleukemia growth in vitro and in vivo. Further proteomics and transcriptomics analysis revealed IFN-{gamma} signaling response as the top CCRL2-regulated pathway in erythroleukemia. Our mechanistic studies support direct CCRL2 driven IFN-{gamma} signaling independent of exogenous IFN-{gamma}, through phosphorylation of STAT1, via JAK2-dependent and independent mechanisms. CCRL2/IFN-{gamma} signaling is upregulated in erythroid leukemias, and TP53 mutated AML without concurrent increase of IFN-{gamma} secretion in the bone marrow microenvironment and is directly induced by TP53 KO. Finally, CCRL2/IFN-{gamma} signaling is associated with the transformation of pre-leukemic single-hit TP53 clones to multi-hit TP53 mutated AML, increased resistance to venetoclax and worse survival in AML. Overall, our findings support that CCRL2 is an essential driver of cell-autonomous IFN-{gamma} signaling response in myeloid neoplasms with erythroid differentiation and TP53 mutations and highlight CCRL2 as a relevant novel target for these neoplasms. One Sentence SummaryCCRL2 is overexpressed in AML with loss-of-function TP53 mutations and erythroid differentiation and promotes IFN-{gamma} signaling response via a cell-intrinsic mechanism.

cancer biology↗

bioRxiv2017

Diagnostic utility of telomere length measurement in a hospital setting

Very short telomere length (TL) provokes cellular senescence in vitro, but the clinical utility of TL measurement in a hospital-based setting has not been determined. We tested the diagnostic and prognostic value of TL measurement by flow cytometry and fluorescence in situ hybridization (flowFISH) in individuals with mutations in telomerase and telomere maintenance genes, and examined prospectively whether TL altered treatment decisions for patients with bone marrow failure. TL had a definable normal range across populations with discrete lower and upper boundaries. TL above the 50th age-adjusted percentile had a 100% negative predictive value for clinically relevant mutations in telomere maintenance genes, but the lower threshold for diagnosis was age-dependent. The extent of deviation from the age-adjusted median correlated with the age at diagnosis of a telomere syndrome as well as the predominant complication. Mild short telomere defects manifested in adults as pulmonary fibrosis-emphysema, while severely short TL manifested in children as bone marrow failure and immunodeficiency. Among 38 newly diagnosed patients with bone marrow failure, TL shorter than the 1st age-adjusted percentile enriched for patients with germline mutations in inherited bone marrow failure genes, such as RUNX1, in addition to telomere maintenance genes. The TL result modified the hematopoietic stem cell donor choice and/or treatment regimen in one-fourth of the cases (9 of 38,24%). TL testing by flowFISH has diagnostic and predictive value in definable clinical settings. In patients with bone marrow failure, it altered treatment decisions for a significant subset.

genetics↗