Ulrich Keller

Prof. Ulrich Keller

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Research Focus & Metrics

Academic Career Length

32Years (1995-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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13 May 2022 in Leukemia
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Journal Article
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AFAndrés José María Ferreri
Andrés José María Ferreri
KCKate Cwynarski
Kate Cwynarski
EPElisa Pulczynski
Elisa Pulczynski
CFChristopher P. Fox
Christopher P. Fox
ESElisabeth Schorb
Elisabeth Schorb
GIGerald Illerhaus
Gerald Illerhaus

3 January 2019 in Head & Face Medicine
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Journal Article
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KSKatharina Storck
Katharina Storck
MBMarkus Brandstetter
Markus Brandstetter
UKUlrich Keller
Ulrich Keller
AKAndreas Knopf
Andreas Knopf
The study analyses clinical characteristics of histologically defined head and neck (H&N) lymphoma to raise the awareness of ENT specialists to the leading symptoms. From 2003 to 2011, all patients with histologically defined H&N lymphoma from our clinic were evaluated. This study identified 221 patients with H&N lymphoma comprising 193 non-Hodgkin lymphomas (NHL) and 28 Hodgkin lymphomas (HL). Among NHL there were 77 indolent (iNHL), 110 aggressive (aNHL), six highly aggressive NHL and further 28 HL. Patients with highly aggressive NHL and HL were significantly younger (p < 0.0001). Corresponding to the leading symptoms, we found nodal and extranodal involvement. NHL demonstrated manifestation in neck lymph nodes, tonsils, major salivary glands, sinonasal-system and hypopharynx/larynx. HL showed exclusive manifestation in lymph nodes of the neck and the tonsils (p < 0.0001). The mean time from first symptoms to diagnosis ranged from 1.5 ± 0.7 months in highly aggressive lymphoma to 7.5 ± 11.5 months in iNHL. The variable clinical presentation of lymphoma is a challenge for the ENT specialist. Fast diagnosis is crucial for rapid treatment, especially in highly aggressive NHL like the Burkitt-lymphoma and HL. A standardized medical history, clinical examination and imaging evaluations paired with patient’s signs, symptoms and demographic knowledge might indicate lymphoma. Biopsies in the H&N region should always be immediately performed in suspicious findings.

1 January 2018 in Theranostics
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Journal Article
Open access
SHStefan Habringer
Stefan Habringer
CLConstantin Lapa
Constantin Lapa
PHPeter Herhaus
Peter Herhaus
MSMargret Schottelius
Margret Schottelius
RIRouzanna Istvanffy
Rouzanna Istvanffy
UKUlrich Keller
Ulrich Keller
C-X-C chemokine receptor 4 (CXCR4) is a transmembrane receptor with pivotal roles in cell homing and hematopoiesis. CXCR4 is also involved in survival, proliferation and dissemination of cancer, including acute lymphoblastic and myeloid leukemia (ALL, AML). Relapsed/refractory ALL and AML are frequently resistant to conventional therapy and novel highly active strategies are urgently needed to overcome resistance.

30 January 2020 in Gut
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ABAlexander Biederstädt
Alexander Biederstädt
ZHZonera Hassan
Zonera Hassan
CSChristian Schneeweis
Christian Schneeweis
MSMarkus Schick
Markus Schick
LSLara Schneider
Lara Schneider
UKUlrich Keller
Ulrich Keller
Objective Pancreatic ductal adenocarcinoma (PDAC) still carries a dismal prognosis with an overall 5-year survival rate of 9%. Conventional combination chemotherapies are a clear advance in the treatment of PDAC; however, subtypes of the disease exist, which exhibit extensive resistance to such therapies. Genomic MYC amplifications represent a distinct subset of PDAC with an aggressive tumour biology. It is clear that hyperactivation of MYC generates dependencies that can be exploited therapeutically. The aim of the study was to find and to target MYC-associated dependencies. Design We analysed human PDAC gene expression datasets. Results were corroborated by the analysis of the small ubiquitin-like modifier (SUMO) pathway in a large PDAC cohort using immunohistochemistry. A SUMO inhibitor was used and characterised using human and murine two-dimensional, organoid and in vivo models of PDAC. Results We observed that MYC is connected to the SUMOylation machinery in PDAC. Components of the SUMO pathway characterise a PDAC subtype with a dismal prognosis and we provide evidence that hyperactivation of MYC is connected to an increased sensitivity to pharmacological SUMO inhibition. Conclusion SUMO inhibitor-based therapies should be further developed for an aggressive PDAC subtype.

1 July 2021 in Blood Advances
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NLNora Liebers
Nora Liebers
JDJohannes Duell
Johannes Duell
DFDonnacha Fitzgerald
Donnacha Fitzgerald
AKAndrea Kerkhoff
Andrea Kerkhoff
DNDaniel Noerenberg
Daniel Noerenberg
SDSascha Dietrich
Sascha Dietrich
The antibody-drug conjugate polatuzumab vedotin (pola) has recently been approved in combination with bendamustine and rituximab (pola-BR) for patients with refractory or relapsed (r/r) large B-cell lymphoma (LBCL). To investigate the efficacy of pola-BR in a real-world setting, we retrospectively analyzed 105 patients with LBCL who were treated in 26 German centers under the national compassionate use program. Fifty-four patients received pola as a salvage treatment and 51 patients were treated with pola with the intention to bridge to chimeric antigen receptor (CAR) T-cell therapy (n = 41) or allogeneic hematopoietic cell transplantation (n = 10). Notably, patients in the salvage and bridging cohort had received a median of 3 prior treatment lines. In the salvage cohort, the best overall response rate was 48.1%. The 6-month progression-free survival and overall survival (OS) was 27.7% and 49.6%, respectively. In the bridging cohort, 51.2% of patients could be successfully bridged with pola to the intended CAR T-cell therapy. The combination of pola bridging and successful CAR T-cell therapy resulted in a 6-month OS of 77.9% calculated from pola initiation. Pola vedotin-rituximab without a chemotherapy backbone demonstrated encouraging overall response rates up to 40%, highlighting both an appropriate alternative for patients unsuitable for chemotherapy and a new treatment option for bridging before leukapheresis in patients intended for CAR T-cell therapy. Furthermore, 7 of 12 patients with previous failure of CAR T-cell therapy responded to a pola-containing regimen. These findings suggest that pola may serve as effective salvage and bridging treatment of r/r LBCL patients.

2 May 2022 in Journal of Clinical Investigation
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Journal Article
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UDUta M. Demel
Uta M. Demel
MBMarlitt Böger
Marlitt Böger
SYSchayan Yousefian
Schayan Yousefian
CGCorinna Grunert
Corinna Grunert
LZLe Zhang
Le Zhang
UKUlrich Keller
Ulrich Keller
Activated SUMOylation is a hallmark of cancer. Starting from a targeted screening for SUMO-regulated immune evasion mechanisms, we identified an evolutionarily conserved function of activated SUMOylation, which attenuated the immunogenicity of tumor cells. Activated SUMOylation allowed cancer cells to evade CD8+ T cell–mediated immunosurveillance by suppressing the MHC class I (MHC-I) antigen-processing and presentation machinery (APM). Loss of the MHC-I APM is a frequent cause of resistance to cancer immunotherapies, and the pharmacological inhibition of SUMOylation (SUMOi) resulted in reduced activity of the transcriptional repressor scaffold attachment factor B (SAFB) and induction of the MHC-I APM. Consequently, SUMOi enhanced the presentation of antigens and the susceptibility of tumor cells to CD8+ T cell–mediated killing. Importantly, SUMOi also triggered the activation of CD8+ T cells and thereby drove a feed-forward loop amplifying the specific antitumor immune response. In summary, we showed that activated SUMOylation allowed tumor cells to evade antitumor immunosurveillance, and we have expanded the understanding of SUMOi as a rational therapeutic strategy for enhancing the efficacy of cancer immunotherapies.