Papers by Eglė Katkevičiūtė
Journal of Clinical Investigation, Jan 4, 2021
Abstract 4038: Discovery of potent and selective inhibitors of the protein tyrosine phosphatases PTPN2 and PTPN1 to trigger anti-tumor immunity through sensitization of tumor cells and activation of immune cells
Cancer Research, Apr 4, 2023
Protein tyrosine phosphatase nonreceptor type 2 (PTPN2) has emerged as a promising cancer immunot... more Protein tyrosine phosphatase nonreceptor type 2 (PTPN2) has emerged as a promising cancer immunotherapy target. Previously, we reported on the functional role of PTPN2 in the pathogenesis of colorectal carcinoma (CRC). We demonstrated increased PTPN2 phosphatase activity correlates with disease progression and decreased immune responses in tumor tissues, while loss of PTPN2 in T-cells or in dendritic cells (DCs) reduces tumor burden in several CRC models and potentiates anti-PD1 efficacy (Katkeviciute et al., 2021). Others reported that loss of PTPN2 in tumor cells sensitizes to immune-mediated tumor killing (Manguso et al., 2017; Goh et al., 2022). Thus, PTPN2 was proposed as a critical node to modulate anti-tumor immunity, and PTPN2 inhibition is expected to enhance anti-tumor immunity by sensitizing tumor cells and by activating immune cells. Recently, also the closely related phosphatase PTPN1 (PTP1B) was demonstrated to restrain T-cell mediated tumor killing (Wiede et al., 2022). Inhibition of Protein Tyrosine Phosphatases has historically been a demanding area for drug discovery. However, both allosteric PTP inhibitors (eg targeting SHP2/PTPN11) and catalytic-site inhibitors (targeting PTPN2/N1) have recently progressed to clinical studies. We now identified a chemical series of novel dual PTPN2/N1 inhibitors. These inhibitors bind to the catalytic site of PTPN2, as confirmed by crystallography. The best molecules of the series are low nM inhibitors of PTPN2 and PTPN1 enzymes with excellent selectivity across other phosphatases. As an immediate consequence of PTPN2/N1 inhibition, these compounds augment phosphorylation of STAT1 and/or STAT5 isoforms in myeloid and T-cell lines, and in primary T-cells, macrophages and DCs. This results in immune-cell activation as evidenced by increased production of effector cytokines (e.g. IFNγ), immune-activation, levels of cytotoxicity markers in T-cells (e.g. granzyme B) as well as upregulation of antigen presentation and co-stimulatory markers in macrophages and DCs. Furthermore, inhibition of PTPN2/N1 sensitizes murine and human cancer cell lines to IFNγ, and enhances immune-mediated tumor killing in co-culture assays in vitro. In vivo evaluation of selected examples is in progress and results will be presented at the conference. Our data indicate that inhibition of PTPN2/N1 phosphatase activity is a powerful pharmacologic strategy to promote anti-tumor immunity, with strong potential to be exploited for cancer immunotherapy both as a single agent treatment in anti-PD1 refractory cancers, and in combination with anti-PD1 therapy. Citation Format: Kalliopi Pervolaraki, Egle Katkeviciute, Dominique Lambin, Sandro Boland, Amuri Kilonda, Vincent Pericolle, Marnik Nijs, Wanda Haeck, Kristine Metzger, Hugo Klaassen, Arnaud Marchand, Patrick Chaltin, Matthias Versele, Marianne Spalinger, Michael Scharl. Discovery of potent and selective inhibitors of the protein tyrosine phosphatases PTPN2 and PTPN1 to trigger anti-tumor immunity through sensitization of tumor cells and activation of immune cells. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 4038.
TiO<sub>2</sub>nanoparticles abrogate the protective effect of the Crohn’s disease-associated variation within the PTPN22 gene locus
Gut, Oct 3, 2022
ObjectiveInflammatory bowel disease (IBD) is a multifactorial condition driven by genetic and env... more ObjectiveInflammatory bowel disease (IBD) is a multifactorial condition driven by genetic and environmental risk factors. A genetic variation in the protein tyrosine phosphatase non-receptor type 22 (PTPN22) gene has been associated with autoimmune disorders while protecting from the IBD subtype Crohn’s disease. Mice expressing the murine orthologous PTPN22-R619W variant are protected from intestinal inflammation in the model of acute dextran sodium sulfate (DSS)-induced colitis. We previously identified food-grade titanium dioxide (TiO2, E171) as a neglected IBD risk factor. Here, we investigate the interplay of the PTPN22 variant and TiO2-mediated effects during IBD pathogenesis.DesignAcute DSS colitis was induced in wild-type and PTPN22 variant mice (PTPN22-R619W) and animals were treated with TiO2nanoparticles during colitis induction. Disease-triggering mechanisms were investigated using bulk and single-cell RNA sequencing.ResultsIn mice, administration of TiO2nanoparticles abrogated the protective effect of the variant, rendering PTPN22-R619W mice susceptible to DSS colitis. In early disease, cytotoxic CD8+T-cells were found to be reduced in the lamina propria of PTPN22-R619W mice, an effect reversed by TiO2administration. Normalisation of T-cell populations correlated with increasedIfngexpression and, at a later stage of disease, the promoted prevalence of proinflammatory macrophages that triggered severe intestinal inflammation.ConclusionOur findings indicate that the consumption of TiO2nanoparticles might have adverse effects on the gastrointestinal health of individuals carrying the PTPN22 variant. This demonstrates that environmental factors interact with genetic risk variants and can reverse a protective mechanism into a disease-promoting effect.
Journal for ImmunoTherapy of Cancer, Feb 1, 2022
Journal of Crohn's and Colitis
Background and Aims Exacerbated immune activation, intestinal dysbiosis and a disrupted intestina... more Background and Aims Exacerbated immune activation, intestinal dysbiosis and a disrupted intestinal barrier are common features among inflammatory bowel disease [IBD] patients. The polyamine spermidine, which is naturally present in all living organisms, is an integral component of the human diet, and exerts beneficial effects in human diseases. Here, we investigated whether spermidine treatment ameliorates intestinal inflammation and offers therapeutic potential for IBD treatment. Methods We assessed the effect of oral spermidine administration on colitis severity in the T cell transfer colitis model in Rag2−/− mice by endoscopy, histology and analysis of markers of molecular inflammation. The effects on the intestinal microbiome were determined by 16S rDNA sequencing of mouse faeces. The impact on intestinal barrier integrity was evaluated in co-cultures of patient-derived macrophages with intestinal epithelial cells. Results Spermidine administration protected mice from intestinal...
International Journal of Molecular Sciences
Environmental and genetic factors have been demonstrated to contribute to the development of infl... more Environmental and genetic factors have been demonstrated to contribute to the development of inflammatory bowel disease (IBD). Recent studies suggested that the food additive; titanium dioxide (TiO2) might play a causative role in the disease. Therefore, in the present study we aimed to explore the interaction between the food additive TiO2 and the well-characterized IBD risk gene protein tyrosine phosphatase non-receptor type 2 (Ptpn2) and their role in the development of intestinal inflammation. Dextran sodium sulphate (DSS)-induced acute colitis was performed in mice lacking the expression of Ptpn2 in myeloid cells (Ptpn2LysMCre) or their wild type littermates (Ptpn2fl/fl) and exposed to the microparticle TiO2. The impact of Ptpn2 on TiO2 signalling pathways and TiO2-induced IL-1β and IL-10 levels were studied using bone marrow-derived macrophages (BMDMs). Ptpn2LysMCre exposed to TiO2 exhibited more severe intestinal inflammation than their wild type counterparts. This effect was...
International Journal of Molecular Sciences
Protein tyrosine phosphatase nonreceptor type 2 (PTPN2) plays a critical role in the pathogenesis... more Protein tyrosine phosphatase nonreceptor type 2 (PTPN2) plays a critical role in the pathogenesis of inflammatory bowel diseases (IBD). Mice lacking PTPN2 in dendritic cells (DCs) develop skin and liver inflammation by the age of 22 weeks due to a generalized loss of tolerance leading to uncontrolled immune responses. The effect of DC-specific PTPN2 loss on intestinal health, however, is unknown. The aim of this study was to investigate the DC-specific role of PTPN2 in the intestine during colitis development. PTPN2fl/flxCD11cCre mice were subjected to acute and chronic DSS colitis as well as T cell transfer colitis. Lamina propria immune cell populations were analyzed using flow cytometry. DC-specific PTPN2 deletion promoted infiltration of B and T lymphocytes, macrophages, and DCs into the lamina propria of unchallenged mice and elevated Th1 abundance during acute DSS colitis, suggesting an important role for PTPN2 in DCs in maintaining intestinal immune cell homeostasis. Surprisi...
Su1029 – Tio2 Nanoparticles Abrogate the Protective Effect of the Autoimmunity-Associated PTPN22 R619W Variant During Acute DSS Colitis
Gastroenterology, 2019
Journal of Crohn's and Colitis, 2020
Background Inflammatory bowel disease (IBD) is caused by a complex interaction among genetic, imm... more Background Inflammatory bowel disease (IBD) is caused by a complex interaction among genetic, immunological, bacterial and environmental factors. In this scenario, protein tyrosine phosphatase non-receptor type-2 (PTPN2) has been recognised as a risk factor for the development of IBD and functional studies revealed a major role for this protein in the development of experimental colitis through the regulation of the inflammasome, among other processes. In the same way, a potential relationship between diet components and IBD was suggested. In fact, it was reported that the food additive titanium dioxide (TiO2) was able to induce inflammasome activation in vitro and increase colitis severity in vivo. These observations led us to hypothesise a putative relationship between PTPN2 and TiO2 that could explain the effects of this microparticle in the pathogenesis of bowel inflammation. Methods DSS colitis model was performed in mice lacking PTPN2 in myeloid cells and their wild-type litte...
Journal of Crohn's and Colitis, 2019
Background: Oncostatin M (OSM) is a proinflammatory and profibrotic cytokine that has been implic... more Background: Oncostatin M (OSM) is a proinflammatory and profibrotic cytokine that has been implicated in the pathogenesis of inflammatory bowel disease (IBD). This is at least partly due to an ability to induce the secretion of cytokines and chemokines from intestinal stromal cells (West et al., Nat Med 2017). However, while mRNA expression is known to be elevated in inflamed bowel tissue from IBD patients, less is known about OSM protein levels and the effect of inhibiting OSM on cytokine production. The objective of this study was to measure OSM protein levels in serum and inflamed intestinal tissue from IBD patients, and to determine the effect of OSM neutralisation on cytokine production in an IBD mucosal explant model. Methods: Serum and involved intestinal mucosa from patients with active moderate/severe ulcerative colitis (UC) or Crohn's disease, along with corresponding samples from healthy volunteers, were obtained with patient informed consent in accordance with ICH GCP under an ethics committee-approved protocol. For the gut explant model, IBD mucosal biopsies from each individual donor were cultured ex vivo for 24 h with either anti-OSM antibody (10 or 40 µg/ml), isotype control antibody or prednisolone (1 µM). Cytokine concentrations were measured in serum, tissue lysates, and explant culture supernatants by ELISA. Results: OSM protein was significantly (p < 0.001) increased in serum from Crohn's and UC patients compared with healthy volunteer samples and significantly (p < 0.05) elevated in intestinal tissue from Crohn's and UC patients compared with healthy control samples. Incubation of human IBD intestinal explants with an anti-OSM antibody reduced spontaneous pro-inflammatory cytokine production. In the UC mucosal explant assay (n = 9 donors), 10 and 40 µg/ ml anti-OSM treatment resulted in a mean 49% and 48% inhibition of IL1β, 36% and 57% inhibition of IL6, and 27% and 43% inhibition of TNFα production, respectively. In the Crohn's mucosal explant assay (n = 13 donors), 10 and 40 µg/ml anti-OSM treatment resulted in a mean 51% and 64% inhibition of IL1β, 57% and 42% inhibition of IL6, and 31% and 37% inhibition of TNFα production, respectively. This degree of cytokine inhibition was greater than that shown for the isotype control. Conclusions: OSM protein is elevated in both serum and inflamed intestinal tissue from IBD patients. OSM neutralisation in the IBD mucosal explant assay reduced spontaneous pro-inflammatory cytokine production. Together these data support targeted approaches to modulating OSM for the treatment of UC and Crohn's disease.
DOP14 TiO2 nanoparticles abrogate the protective effect of the autoimmunity-associated PTPN22R619W variant during acute DSS colitis
Journal of Crohn's and Colitis, 2019
Frontiers in Immunology, Aug 18, 2020
Protein tyrosine phosphatase non-receptor type 2 (PTPN2) plays a pivotal role in immune homeostas... more Protein tyrosine phosphatase non-receptor type 2 (PTPN2) plays a pivotal role in immune homeostasis and has been associated with human autoimmune and chronic inflammatory diseases. Though PTPN2 is well-characterized in lymphocytes, little is known about its function in innate immune cells. Our findings demonstrate that dendritic cell (DC)-intrinsic PTPN2 might be the key to explain the central role for PTPN2 in the immune system to maintain immune tolerance. Partial genetic PTPN2 ablation in DCs resulted in spontaneous inflammation, particularly in skin, liver, lung and kidney 22 weeks post-birth. DC-specific PTPN2 controls steady-state immune cell composition and even incomplete PTPN2 deficiency in DCs resulted in enhanced organ infiltration of conventional type 2 DCs, accompanied by expansion of IFNγ-producing effector T-cells. Consequently, the phenotypic effects of DC-specific PTPN2 deficiency were abolished in T-cell deficient Rag knock-out mice. Our data add substantial knowledge about the molecular mechanisms to prevent inflammation and maintain tissue tolerance.
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Papers by Eglė Katkevičiūtė