Publications by authors named "Ursula Stalmann"

4 Publications

  • Page 1 of 1

Heterogeneous bone-marrow stromal progenitors drive myelofibrosis via a druggable alarmin axis.

Cell Stem Cell 2020 Dec 9. Epub 2020 Dec 9.

Department of Hematology, Erasmus Medical Center, Rotterdam 3015GD, the Netherlands; Department of Cell Biology, Institute for Biomedical Engineering, Faculty of Medicine, RWTH Aachen University, Pauwelsstrasse 30, 52074 Aachen, Germany; Oncode Institute, Erasmus Medical Center, Rotterdam 3015GD, the Netherlands. Electronic address:

Functional contributions of individual cellular components of the bone-marrow microenvironment to myelofibrosis (MF) in patients with myeloproliferative neoplasms (MPNs) are incompletely understood. We aimed to generate a comprehensive map of the stroma in MPNs/MFs on a single-cell level in murine models and patient samples. Our analysis revealed two distinct mesenchymal stromal cell (MSC) subsets as pro-fibrotic cells. MSCs were functionally reprogrammed in a stage-dependent manner with loss of their progenitor status and initiation of differentiation in the pre-fibrotic and acquisition of a pro-fibrotic and inflammatory phenotype in the fibrotic stage. The expression of the alarmin complex S100A8/S100A9 in MSC marked disease progression toward the fibrotic phase in murine models and in patient stroma and plasma. Tasquinimod, a small-molecule inhibiting S100A8/S100A9 signaling, significantly ameliorated the MPN phenotype and fibrosis in JAK2V617F-mutated murine models, highlighting that S100A8/S100A9 is an attractive therapeutic target in MPNs.
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http://dx.doi.org/10.1016/j.stem.2020.11.004DOI Listing
December 2020

First-In-Class CD13-Targeted Tissue Factor tTF-NGR in Patients with Recurrent or Refractory Malignant Tumors: Results of a Phase I Dose-Escalation Study.

Cancers (Basel) 2020 Jun 7;12(6). Epub 2020 Jun 7.

Department of Medicine A, Hematology, Oncology, University Hospital Muenster, D-48149 Muenster, Germany.

Background: Aminopeptidase N (CD13) is present on tumor vasculature cells and some tumor cells. Truncated tissue factor (tTF) with a C-terminal NGR-peptide (tTF-NGR) binds to CD13 and causes tumor vascular thrombosis with infarction.

Methods: We treated 17 patients with advanced cancer beyond standard therapies in a phase I study with tTF-NGR (1-h infusion, central venous access, 5 consecutive days, and rest periods of 2 weeks). The study allowed intraindividual dose escalations between cycles and established Maximum Tolerated Dose (MTD) and Dose-Limiting Toxicity (DLT) by verification cohorts.

Results: MTD was 3 mg/m tTF-NGR/day × 5, q day 22. DLT was an isolated and reversible elevation of high sensitivity (hs) Troponin T hs without clinical sequelae. Three thromboembolic events (grade 2), tTF-NGR-related besides other relevant risk factors, were reversible upon anticoagulation. Imaging by contrast-enhanced ultrasound (CEUS) and dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) showed major tumor-specific reduction of blood flow in all measurable lesions as proof of principle for the mode of action of tTF-NGR. There were no responses as defined by Response Evaluation Criteria in Solid Tumors (RECIST), although some lesions showed intratumoral hemorrhage and necrosis after tTF-NGR application. Pharmacokinetic analysis showed a t of 8 to 9 h without accumulation in daily administrations.

Conclusion: tTF-NGR is safely applicable with this regimen. Imaging showed selective reduction of tumor blood flow and intratumoral hemorrhage and necrosis.
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http://dx.doi.org/10.3390/cancers12061488DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7352358PMC
June 2020

Rps14, Csnk1a1 and miRNA145/miRNA146a deficiency cooperate in the clinical phenotype and activation of the innate immune system in the 5q- syndrome.

Leukemia 2019 07 16;33(7):1759-1772. Epub 2019 Jan 16.

Department of Hematology, Oncology, Hemostaseology, and Stem Cell Transplantation, RWTH Aachen University, Aachen, Germany.

RPS14, CSNK1A1, and miR-145 are universally co-deleted in the 5q- syndrome, but mouse models of each gene deficiency recapitulate only a subset of the composite clinical features. We analyzed the combinatorial effect of haploinsufficiency for Rps14, Csnk1a1, and miRNA-145, using mice with genetically engineered, conditional heterozygous inactivation of Rps14 and Csnk1a1 and stable knockdown of miR-145/miR-146a. Combined Rps14/Csnk1a1/miR-145/146a deficiency recapitulated the cardinal features of the 5q- syndrome, including (1) more severe anemia with faster kinetics than Rps14 haploinsufficiency alone and (2) pathognomonic megakaryocyte morphology. Macrophages, regulatory cells of erythropoiesis and the innate immune response, were significantly increased in Rps14/Csnk1a1/miR-145/146a deficient mice as well as in 5q- syndrome patient bone marrows and showed activation of the innate immune response, reflected by increased expression of S100A8, and decreased phagocytic function. We demonstrate that Rps14/Csnk1a1/miR-145 and miR-146a deficient macrophages alter the microenvironment and induce S100A8 expression in the mesenchymal stem cell niche. The increased S100A8 expression in the mesenchymal niche was confirmed in 5q- syndrome patients. These data indicate that intrinsic defects of the 5q- syndrome hematopoietic stem cell directly alter the surrounding microenvironment, which in turn affects hematopoiesis as an extrinsic mechanism.
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http://dx.doi.org/10.1038/s41375-018-0350-3DOI Listing
July 2019

Aminopeptidase N (CD13): Expression, Prognostic Impact, and Use as Therapeutic Target for Tissue Factor Induced Tumor Vascular Infarction in Soft Tissue Sarcoma.

Transl Oncol 2018 Dec 17;11(6):1271-1282. Epub 2018 Aug 17.

Department of Medicine A, Hematology, Oncology, University Hospital Muenster, Muenster, Germany.

Aminopeptidase N (CD13) is expressed on tumor vasculature and tumor cells. It represents a candidate for targeted therapy, e.g., by truncated tissue factor (tTF)-NGR, binding to CD13, and causing tumor vascular thrombosis. We analyzed CD13 expression by immunohistochemistry in 97 patients with STS who were treated by wide resection and uniform chemo-radio-chemotherapy. Using a semiquantitative score with four intensity levels, CD13 was expressed by tumor vasculature, or tumor cells, or both (composite value, intensity scores 1-3) in 93.9% of the STS. In 49.5% tumor cells, in 48.5% vascular/perivascular cells, and in 58.8%, composite value showed strong intensity score 3 staining. Leiomyosarcoma and synovial sarcoma showed low expression; fibrosarcoma and undifferentiated pleomorphic sarcoma showed high expression. We found a significant prognostic impact of CD13, as high expression in tumor cells or vascular/perivascular cells correlated with better relapse-free survival and overall survival. CD13 retained prognostic significance in multivariable analyses. Systemic tTF-NGR resulted in significant growth reduction of CD13-positive human HT1080 sarcoma cell line xenografts. Our results recommend further investigation of tTF-NGR in STS patients. CD13 might be a suitable predictive biomarker for patient selection.
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http://dx.doi.org/10.1016/j.tranon.2018.08.004DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6113655PMC
December 2018