1
|
Ehm PAH, Horn S, Hoffer K, Kriegs M, Horn M, Giehler S, Nalaskowski M, Rehbach C, Horstmann MA, Jücker M. Ikaros sets the threshold for negative B-cell selection by regulation of the signaling strength of the AKT pathway. Cell Commun Signal 2024; 22:360. [PMID: 38992657 PMCID: PMC11241878 DOI: 10.1186/s12964-024-01732-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2024] [Accepted: 07/02/2024] [Indexed: 07/13/2024] Open
Abstract
Inhibitory phosphatases, such as the inositol-5-phosphatase SHIP1 could potentially contribute to B-cell acute lymphoblastic leukemia (B-ALL) by raising the threshold for activation of the autoimmunity checkpoint, allowing malignant cells with strong oncogenic B-cell receptor signaling to escape negative selection. Here, we show that SHIP1 is differentially expressed across B-ALL subtypes and that high versus low SHIP1 expression is associated with specific B-ALL subgroups. In particular, we found high SHIP1 expression in both, Philadelphia chromosome (Ph)-positive and ETV6-RUNX1-rearranged B-ALL cells. As demonstrated by targeted knockdown of SHIP1 by RNA interference, proliferation of B-ALL cells in vitro and their tumorigenic spread in vivo depended in part on SHIP1 expression. We investigated the regulation of SHIP1, as an important antagonist of the AKT signaling pathway, by the B-cell-specific transcription factor Ikaros. Targeted restoration of Ikaros and pharmacological inhibition of the antagonistic casein kinase 2, led to a strong reduction in SHIP1 expression and at the same time to a significant inhibition of AKT activation and cell growth. Importantly, the tumor suppressive function of Ikaros was enhanced by a SHIP1-dependent additive effect. Furthermore, our study shows that all three AKT isoforms contribute to the pro-mitogenic and anti-apoptotic signaling in B-ALL cells. Conversely, hyperactivation of a single AKT isoform is sufficient to induce negative selection by increased oxidative stress. In summary, our study demonstrates the regulatory function of Ikaros on SHIP1 expression in B-ALL and highlights the relevance of sustained SHIP1 expression to prevent cells with hyperactivated PI3K/AKT/mTOR signaling from undergoing negative selection.
Collapse
Affiliation(s)
- Patrick A H Ehm
- Institute of Biochemistry and Signal Transduction, Center for Experimental Medicine, University Medical Center Hamburg-Eppendorf, Martinistr. 52, Hamburg, 20246, Germany.
- Department of Pediatric Oncology and Hematology, Research Institute Children's Cancer Center Hamburg, University Medical Center, Hamburg, 20246, Germany.
| | - Stefan Horn
- Research Department Cell and Gene Therapy, Department of Stem Cell Transplantation, University Medical Center Hamburg-Eppendorf, Hamburg, 20246, Germany
| | - Konstantin Hoffer
- UCCH Kinomics Core Facility, University Cancer Center Hamburg (UCCH), University Medical Center Hamburg-Eppendorf, Hamburg, 20246, Germany
- Department of Radiotherapy and Radiation Oncology, University Medical Center Hamburg-Eppendorf, Hamburg, 20246, Germany
| | - Malte Kriegs
- UCCH Kinomics Core Facility, University Cancer Center Hamburg (UCCH), University Medical Center Hamburg-Eppendorf, Hamburg, 20246, Germany
- Department of Radiotherapy and Radiation Oncology, University Medical Center Hamburg-Eppendorf, Hamburg, 20246, Germany
| | - Michael Horn
- University Cancer Center Hamburg, University Medical Center Hamburg-Eppendorf, Hamburg, 20246, Germany
- Mildred Scheel Cancer Career Center Hamburg, University Medical Center Hamburg-Eppendorf, Hamburg, 20246, Germany
| | - Susanne Giehler
- Institute of Biochemistry and Signal Transduction, Center for Experimental Medicine, University Medical Center Hamburg-Eppendorf, Martinistr. 52, Hamburg, 20246, Germany
| | - Marcus Nalaskowski
- Institute of Biochemistry and Signal Transduction, Center for Experimental Medicine, University Medical Center Hamburg-Eppendorf, Martinistr. 52, Hamburg, 20246, Germany
| | - Christoph Rehbach
- Institute of Biochemistry and Signal Transduction, Center for Experimental Medicine, University Medical Center Hamburg-Eppendorf, Martinistr. 52, Hamburg, 20246, Germany
- Department of Human Medicine, MSH Medical School Hamburg, Hamburg, Germany
| | - Martin A Horstmann
- Department of Pediatric Oncology and Hematology, Research Institute Children's Cancer Center Hamburg, University Medical Center, Hamburg, 20246, Germany
| | - Manfred Jücker
- Institute of Biochemistry and Signal Transduction, Center for Experimental Medicine, University Medical Center Hamburg-Eppendorf, Martinistr. 52, Hamburg, 20246, Germany
| |
Collapse
|
2
|
Yeoh WJ, Krebs P. SHIP1 and its role for innate immune regulation-Novel targets for immunotherapy. Eur J Immunol 2023; 53:e2350446. [PMID: 37742135 DOI: 10.1002/eji.202350446] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Revised: 08/03/2023] [Accepted: 09/21/2023] [Indexed: 09/25/2023]
Abstract
Phosphoinositide-3-kinase/AKT (PI3K/AKT) signaling plays key roles in the regulation of cellular activity in both health and disease. In immune cells, this PI3K/AKT pathway is critically regulated by the phosphoinositide phosphatase SHIP1, which has been reported to modulate the function of most immune subsets. In this review, we summarize our current knowledge of SHIP1 with a focus on innate immune cells, where we reflect on the most pertinent aspects described in the current literature. We also present several small-molecule agonists and antagonists of SHIP1 developed over the last two decades, which have led to improved outcomes in several preclinical models of disease. We outline these promising findings and put them in relation to human diseases with unmet medical needs, where we discuss the most attractive targets for immune therapies based on SHIP1 modulation.
Collapse
Affiliation(s)
- Wen Jie Yeoh
- Institute of Tissue Medicine and Pathology, University of Bern, Bern, Switzerland
- Graduate School for Cellular and Biomedical Sciences, University of Bern, Bern, Switzerland
| | - Philippe Krebs
- Institute of Tissue Medicine and Pathology, University of Bern, Bern, Switzerland
| |
Collapse
|
3
|
Ehm P, Rietow R, Wegner W, Bußmann L, Kriegs M, Dierck K, Horn S, Streichert T, Horstmann M, Jücker M. SHIP1 Is Present but Strongly Downregulated in T-ALL, and after Restoration Suppresses Leukemia Growth in a T-ALL Xenotransplantation Mouse Model. Cells 2023; 12:1798. [PMID: 37443832 PMCID: PMC10341211 DOI: 10.3390/cells12131798] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Revised: 06/23/2023] [Accepted: 07/03/2023] [Indexed: 07/15/2023] Open
Abstract
Acute lymphoblastic leukemia (ALL) is the most common cause of cancer-related death in children. Despite significantly increased chances of cure, especially for high-risk ALL patients, it still represents a poor prognosis for a substantial fraction of patients. Misregulated proteins in central switching points of the cellular signaling pathways represent potentially important therapeutic targets. Recently, the inositol phosphatase SHIP1 (SH2-containing inositol 5-phosphatase) has been considered as a tumor suppressor in leukemia. SHIP1 serves as an important negative regulator of the PI3K/AKT signaling pathway, which is frequently constitutively activated in primary T-ALL. In contrast to other reports, we show for the first time that SHIP1 has not been lost in T-ALL cells, but is strongly downregulated. Reduced expression of SHIP1 leads to an increased activation of the PI3K/AKT signaling pathway. SHIP1-mRNA expression is frequently reduced in primary T-ALL samples, which is recapitulated by the decrease in SHIP1 expression at the protein level in seven out of eight available T-ALL patient samples. In addition, we investigated the change in the activity profile of tyrosine and serine/threonine kinases after the restoration of SHIP1 expression in Jurkat T-ALL cells. The tyrosine kinase receptor subfamilies of NTRK and PDGFR, which are upregulated in T-ALL subgroups with low SHIP1 expression, are significantly disabled after SHIP1 reconstitution. Lentiviral-mediated reconstitution of SHIP1 expression in Jurkat cells points to a decreased cellular proliferation upon transplantation into NSG mice in comparison to the control cohort. Together, our findings will help to elucidate the complex network of cell signaling proteins, further support a functional role for SHIP1 as tumor suppressor in T-ALL and, much more importantly, show that full-length SHIP1 is expressed in T-ALL samples.
Collapse
Affiliation(s)
- Patrick Ehm
- Institute of Biochemistry and Signal Transduction, Center for Experimental Medicine, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg, Germany
- Research Institute Children’s Cancer Center Hamburg, Hamburg and Department of Pediatric Oncology and Hematology, University Medical Center, 20246 Hamburg, Germany
| | - Ruth Rietow
- Institute of Biochemistry and Signal Transduction, Center for Experimental Medicine, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg, Germany
- Research Institute Children’s Cancer Center Hamburg, Hamburg and Department of Pediatric Oncology and Hematology, University Medical Center, 20246 Hamburg, Germany
| | - Wiebke Wegner
- Institute of Biochemistry and Signal Transduction, Center for Experimental Medicine, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg, Germany
| | - Lara Bußmann
- Department of Otorhinolaryngology, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
- UCCH Kinomics Core Facility, University Cancer Center Hamburg (UCCH), University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
| | - Malte Kriegs
- UCCH Kinomics Core Facility, University Cancer Center Hamburg (UCCH), University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
- Center for Oncology, Clinic for Radiation Therapy and Radiation Oncology, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
| | - Kevin Dierck
- Research Institute Children’s Cancer Center Hamburg, Hamburg and Department of Pediatric Oncology and Hematology, University Medical Center, 20246 Hamburg, Germany
| | - Stefan Horn
- Research Department Cell and Gene Therapy, Department of Stem Cell Transplantation, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
| | - Thomas Streichert
- Institute for Clinical Chemistry, University Hospital Köln, 50937 Cologne, Germany
| | - Martin Horstmann
- Research Institute Children’s Cancer Center Hamburg, Hamburg and Department of Pediatric Oncology and Hematology, University Medical Center, 20246 Hamburg, Germany
| | - Manfred Jücker
- Institute of Biochemistry and Signal Transduction, Center for Experimental Medicine, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg, Germany
| |
Collapse
|