A

Exploiting Synthetic Lethality between Germline BRCA1 Haploinsufficiency and PARP Inhibition in JAK2V617F-Positive Myeloproliferative Neoplasms

International Journal of Molecular Sciences, vol. 24, pp. 17560

Abstract

Myeloproliferative neoplasms (MPN) are rare hematologic disorders characterized by clonal hematopoiesis. Familial clustering is observed in a subset of cases, with a notable proportion exhibiting heterozygous germline mutations in DNA double-strand break repair genes (e.g., BRCA1). We investigated the therapeutic potential of targeting BRCA1 haploinsufficiency alongside the JAK2V617F driver mutation. We assessed the efficacy of combining the PARP inhibitor olaparib with interferon-alpha (IFNα) in CRISPR/Cas9-engineered Brca1+/− Jak2V617F-positive 32D cells. Olaparib treatment induced a higher number of DNA double-strand breaks, as demonstrated by γH2AX analysis through Western blot (p = 0.024), flow cytometry (p = 0.013), and confocal microscopy (p = 0.071). RAD51 foci formation was impaired in Brca1+/− cells compared to Brca1+/+ cells, indicating impaired homologous recombination repair due to Brca1 haploinsufficiency. Importantly, olaparib enhanced apoptosis while diminishing cell proliferation and viability in Brca1+/− cells compared to Brca1+/+ cells. These effects were further potentiated by IFNα. Olaparib induced interferon-stimulated genes and increased endogenous production of IFNα in Brca1+/− cells. These responses were abrogated by STING inhibition. In conclusion, our findings suggest that the combination of olaparib and IFNα presents a promising therapeutic strategy for MPN patients by exploiting the synthetic lethality between germline BRCA1 mutations and the JAK2V617F MPN driver mutation.

Authors 9

  1. RWTH Aachen University

    Affiliation as printed

    Center for Integrated Oncology Aachen Bonn Cologne Düsseldorf (CIO ABCD), 52074 Aachen, Germany

    Department of Hematology, Oncology, Hemostaseology, and Stem Cell Transplantation, Faculty of Medicine, RWTH Aachen University, 52074 Aachen, Germany

  2. RWTH Aachen University

    Affiliation as printed

    Center for Integrated Oncology Aachen Bonn Cologne Düsseldorf (CIO ABCD), 52074 Aachen, Germany

    Department of Hematology, Oncology, Hemostaseology, and Stem Cell Transplantation, Faculty of Medicine, RWTH Aachen University, 52074 Aachen, Germany

  3. RWTH Aachen University

    Affiliation as printed

    Center for Integrated Oncology Aachen Bonn Cologne Düsseldorf (CIO ABCD), 52074 Aachen, Germany

    Department of Hematology, Oncology, Hemostaseology, and Stem Cell Transplantation, Faculty of Medicine, RWTH Aachen University, 52074 Aachen, Germany

  4. RWTH Aachen University

    Affiliation as printed

    Confocal Microscopy Facility, Interdisciplinary Center for Clinical Research IZKF, RWTH Aachen University, 52074 Aachen, Germany

  5. RWTH Aachen University

    Affiliation as printed

    Department of Biochemistry, Faculty of Medicine, RWTH Aachen University, 52074 Aachen, Germany

  6. RWTH Aachen University

    Affiliation as printed

    Center for Integrated Oncology Aachen Bonn Cologne Düsseldorf (CIO ABCD), 52074 Aachen, Germany

    Department of Hematology, Oncology, Hemostaseology, and Stem Cell Transplantation, Faculty of Medicine, RWTH Aachen University, 52074 Aachen, Germany

  7. RWTH Aachen University

    Affiliation as printed

    Center for Integrated Oncology Aachen Bonn Cologne Düsseldorf (CIO ABCD), 52074 Aachen, Germany

    Department of Hematology, Oncology, Hemostaseology, and Stem Cell Transplantation, Faculty of Medicine, RWTH Aachen University, 52074 Aachen, Germany

  8. RWTH Aachen University

    Affiliation as printed

    Center for Integrated Oncology Aachen Bonn Cologne Düsseldorf (CIO ABCD), 52074 Aachen, Germany

    Department of Hematology, Oncology, Hemostaseology, and Stem Cell Transplantation, Faculty of Medicine, RWTH Aachen University, 52074 Aachen, Germany

  9. RWTH Aachen University

    Affiliation as printed

    Center for Integrated Oncology Aachen Bonn Cologne Düsseldorf (CIO ABCD), 52074 Aachen, Germany

    Department of Hematology, Oncology, Hemostaseology, and Stem Cell Transplantation, Faculty of Medicine, RWTH Aachen University, 52074 Aachen, Germany

Cited by 7 stored of 7

7 results

No patents citing this paper on Lens.org (checked 2026-10-06).

References 36