Publications by authors named "Semjon Willier"

Article Synopsis
  • Scientists are working on new cancer treatments called immunotherapies, especially using CAR T cells, which have shown great results for kids with a type of leukemia.
  • When kids' leukemia comes back or doesn’t respond to regular treatments, they need a different kind of temporary treatment called bridging therapy before getting CAR T cells.
  • A group of doctors in Europe is trying to create guidelines for this bridging therapy to make sure it’s more effective and consistent for all kids with this kind of cancer.
View Article and Find Full Text PDF

Circular RNA (circRNA) is a noncoding RNA class with important implications for gene expression regulation, mostly by interaction with other RNA species or RNA-binding proteins. While the commonly applied short-read Illumina RNA-sequencing techniques can be used to detect circRNAs, their full sequence is not revealed. However, the complete sequence information is needed to analyze potential interactions and thus the mechanism of action of circRNAs.

View Article and Find Full Text PDF

Therapeutic targeting of inhibitory checkpoint molecules in combination with chimeric antigen receptor (CAR) T cells is currently investigated in a variety of clinical studies for treatment of hematologic and solid malignancies. However, the impact of co-inhibitory axes and their therapeutic implication remains understudied for the majority of acute leukemias due to their low immunogenicity/mutational load. The inhibitory exhaustion molecule TIM-3 is an important marker for the interaction of T cells with leukemic cells.

View Article and Find Full Text PDF

Objectives: Exploiting the forces of human T cells for treatment has led to the current paradigm of emerging immunotherapy strategies. Genetic engineering of the T-cell receptor (TCR) redirects specificity, ablates alloreactivity and brings significant progress and off-the-shelf options to emerging adoptive T-cell transfer (ACT) approaches. Targeted CRISPR/Cas9-mediated double-strand breaks in the DNA enable knockout or knock-in engineering.

View Article and Find Full Text PDF

Viral infections cause life-threatening disease in immunocompromised patients and especially following transplantation. T cell receptor (TCR) engineering redirects specificity and can bring significant progress to emerging adoptive T cell transfer (ACT) approaches. T cell epitopes are well described, although knowledge is limited on which TCRs mediate protective immunity.

View Article and Find Full Text PDF

Emerging immunotherapies such as chimeric antigen receptor T cells have advanced the treatment of acute lymphoblastic leukemia. In contrast, long-term control of acute myeloid leukemia (AML) cannot be achieved by single lineage-specific targeting while sparing benign hematopoiesis. In addition, heterogeneity of AML warrants combinatorial targeting, and several suitable immunotargets (HAVCR2/CD33 and HAVCR2/CLEC12A) have been identified in adult AML.

View Article and Find Full Text PDF

Background: High-dose myeloablative conditioning prior to autologous hematopoietic stem cell transplantation (autoHSCT) in pediatric patients is usually highly emetogenic. The antiemetic neurokinin-1 receptor antagonist fosaprepitant was safe and effective in children receiving highly emetogenic chemotherapy. Data on fosaprepitant during autoHSCT in children are currently not available.

View Article and Find Full Text PDF

Background: Relapsed/refractory B-precursor acute lymphoblastic leukemia (BCP-ALL) remains a major therapeutic challenge in pediatric hematology. Chimeric antigen receptor (CAR) T cells targeting CD19 have shown remarkable initial response rates in BCP-ALL patients, while long-term leukemia control rate is only about 50%. So far, main mechanisms of BCP-ALL relapse after CD19-CAR T-cell therapy have been either insufficient CAR T-cell persistence in vivo or loss of surface CD19.

View Article and Find Full Text PDF

Immunosuppression posttransplantation exposes patients to an increased risk for refractory viral infections as an important cause of morbidity and mortality. Protective T cell immunity can be restored by adoptive T cell transfer, but ongoing immunosuppression limits efficacy of T cell responses. In order to deliver protection against viral pathogens and allow at the same time necessary steroid therapy, we generated glucocorticoid-resistant T cells by CRISPR-Cas9-mediated knockout of the glucocorticoid receptor in primary human virus-specific T cell products.

View Article and Find Full Text PDF

Anti-CD19 chimeric antigen receptor (CAR) T cells showed significant antileukemic activity in B-precursor acute lymphoblastic leukemia (ALL). Allogeneic, HLA-mismatched off-the-shelf third-party donors may offer ideal fitness of the effector cells, but carry the risk of graft-versus-host disease. Knockout (KO) of the endogenous T-cell receptor (TCR) in CD19-CAR-T cells may be a promising solution.

View Article and Find Full Text PDF

Interaction of malignancies with tissue-specific immune cells has gained interest for prognosis and intervention of emerging immunotherapies. We analyzed bone marrow T cells (bmT) as tumor-infiltrating lymphocytes in pediatric precursor-B cell acute lymphoblastic leukemia (ALL). Based on data from 100 patients, we show that ALL is associated with late-stage CD4 phenotype and loss of early CD8 T cells.

View Article and Find Full Text PDF

Background: Chemotherapy-induced nausea and vomiting (CINV) belong among the most burdensome side effects in hemato-oncology. Mostly, a combination of ondansetron and dexamethasone is used as antiemetic prophylaxis in pediatric patients undergoing emetogenic chemotherapy. However, dexamethasone is prohibited in different pediatric chemotherapy protocols.

View Article and Find Full Text PDF

Background: Medulloblastoma is the most common malignant brain tumor in childhood and adolescence. Although some patients present with distinct genetic alterations, such as mutated TP53 or MYC amplification, pediatric medulloblastoma is a tumor entity with minimal mutational load and low immunogenicity.

Methods: We identified tumor-specific mutations using next-generation sequencing of medulloblastoma DNA and RNA derived from primary tumor samples from pediatric patients.

View Article and Find Full Text PDF

Background: Allogeneic hematopoietic stem cell transplantation (HSCT) can expose patients to a transient but marked immunosuppression, during which viral infections are an important cause of morbidity and mortality. Adoptive transfer of virus-specific T cells is an attractive approach to restore protective T -cell immunity in patients with refractory viral infections after allogeneic HSCT.

Objectives: This narrative review summarizes clinical evidence and developments of almost 30 years of adoptive T -cell transfer.

View Article and Find Full Text PDF

Relapsed/refractory B-precursor acute lymphoblastic leukemia (pre-B ALL) remains a major therapeutic challenge. Chimeric antigen receptor (CAR) T cells are promising treatment options. Central memory T cells (Tcm) and stem cell-like memory T cells (Tscm) are known to promote sustained proliferation and persistence after T-cell therapy, constituting essential preconditions for treatment efficacy.

View Article and Find Full Text PDF

Background Information: Ewing's sarcoma (ES) is the second most common bone-associated malignancy in children and is driven by the fusion oncogene EWS/FLI1 and characterised by rapid growth and early metastasis. Here, we explored the role of the Zyxin-related protein thyroid receptor interacting protein 6 (TRIP6) in ES. The Zyxin family comprises seven homologous proteins involved in migration and proliferation of many cell types of which Zyxin has been described as a tumour suppressor in ES.

View Article and Find Full Text PDF

Lysophosphatidic acid (LPA) is a ubiquitously present signalling molecule involved in diverse cellular processes such as cell migration, proliferation and differentiation. LPA acts as an autocrine and/or paracrine signalling molecule via different G-protein-coupled LPA receptors (LPARs) that trigger a broad range of intracellular signalling cascades, especially the RHOA pathway. Mounting evidence suggests a crucial role of the LPA/LPAR-axis in cancer cell metastasis and promising studies are underway to investigate the therapeutic potential of LPAR-antagonists.

View Article and Find Full Text PDF

Integrating signals from the ECM (extracellular matrix) via the cell surface into the nucleus is an essential feature of multicellular life and often malfunctions in cancer. To date many signal transducers known as shuttle proteins have been identified that act as both: a cytoskeletal and a signalling protein. Here, we highlight the interesting member of the Zyxin family TRIP6 [thyroid receptor interactor protein 6; also designated ZRP-1 (zyxin-related protein 1)] and review current literature to define its role in cell physiology and cancer.

View Article and Find Full Text PDF