Tumors use indoleamine 2,3-dioxygenase-1 (IDO1) as a major mechanism to induce an immunosuppressive microenvironment. IDO1 expression is upregulated in many cancers and considered to be a resistance ...mechanism to immune checkpoint therapies. IDO1 is induced in response to inflammatory stimuli such as IFNγ and promotes immune tolerance by depleting tryptophan and producing tryptophan catabolites, including kynurenine, in the tumor microenvironment. This leads to effector T-cell anergy and enhanced T
function through upregulation of FoxP3. As a nexus for the induction of key immunosuppressive mechanisms, IDO1 represents an important immunotherapeutic target in oncology. Here, we report the identification and characterization of the novel selective, orally bioavailable IDO1 inhibitor EOS200271/PF-06840003. It reversed IDO1-induced T-cell anergy
In mice carrying syngeneic tumor grafts, PF-06840003 reduced intratumoral kynurenine levels by over 80% and inhibited tumor growth both in monotherapy and, with an increased efficacy, in combination with antibodies blocking the immune checkpoint ligand PD-L1. We demonstrate that anti-PD-L1 therapy results in increased IDO1 metabolic activity thereby providing additional mechanistic rationale for combining PD-(L)1 blockade with IDO1 inhibition in cancer immunotherapies. Supported by these preclinical data and favorable predicted human pharmacokinetic properties of PF-06840003, a phase I open-label, multicenter clinical study (NCT02764151) has been initiated.
Tryptophan catabolism is used by tumors to resist immune attack. It can be catalyzed by indoleamine 2,3-dioxygenase (IDO1) and tryptophan 2,3-dioxygenase (TDO). IDO1 is frequently expressed in tumors ...and has been widely studied as a potential therapeutic target to reduce resistance to cancer immunotherapy. In contrast, TDO expression in tumors is not well characterized. Several human tumor cell lines constitutively express enzymatically active TDO. In human tumor samples, TDO expression has previously been detected by transcriptomics, but the lack of validated antibodies has precluded detection of the TDO protein and identification of TDO-expressing cells. Here, we developed novel TDO-specific monoclonal antibodies and confirmed by immunohistochemistry the expression of TDO in the majority of human cancers. In all hepatocarcinomas (10/10), TDO was expressed by most tumor cells. Some glioblastomas (10/39) and kidney carcinomas (1/10) also expressed TDO in tumor cells themselves but only in focal tumor areas. In addition, all cancers tested contained foci of nontumoral TDO-expressing cells, which were identified as pericytes by their expression of PDGFRβ and their location in vascular structures. These TDO-expressing pericytes belonged to morphologically abnormal tumor vessels and were found in high-grade tumors in the vicinity of necrotic or hemorrhagic areas, which were characterized by neoangiogenesis. We observed similar TDO-expressing pericytes in inflammatory pulmonary lesions containing granulation tissue, and in chorionic villi, two tissue types that also feature neoangiogenesis. Our results confirm TDO as a relevant immunotherapeutic target in hepatocellular carcinoma and suggest a proangiogenic role of TDO in other cancer types.
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The incidence of campylobacteriosis has substantially increased over the past decade, notably in France. Secondary localizations complicating invasive infections are poorly described. We aimed to ...describe vascular infection or endocarditis caused by Campylobacter spp. We included 57 patients from a nationwide 5-year retrospective study on Campylobacter spp. bacteremia conducted in France; 44 patients had vascular infections, 12 had endocarditis, and 1 had both conditions. Campylobacter fetus was the most frequently involved species (83%). Antibiotic treatment involved a β-lactam monotherapy (54%) or was combined with a fluoroquinolone or an aminoglycoside (44%). The mortality rate was 25%. Relapse occurred in 8% of cases and was associated with delayed initiation of an efficient antimicrobial therapy after the first symptoms, diabetes, and coexistence of an osteoarticular location. Cardiovascular Campylobacter spp. infections are associated with a high mortality rate. Systematically searching for those localizations in cases of C. fetus bacteremia may be warranted.
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DOBA, IZUM, KILJ, NUK, ODKLJ, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The incidence of campylobacteriosis has substantially increased over the past decade, notably in France. Secondary localizations complicating invasive infections are poorly described. We aimed to ...describe vascular infection or endocarditis caused by Campylobacter spp. We included 57 patients from a nationwide 5-year retrospective study on Campylobacter spp. bacteremia conducted in France; 44 patients had vascular infections, 12 had endocarditis, and 1 had both conditions. Campylobacter fetus was the most frequently involved species (83%). Antibiotic treatment involved a β-lactam monotherapy (54%) or was combined with a fluoroquinolone or an aminoglycoside (44%). The mortality rate was 25%. Relapse occurred in 8% of cases and was associated with delayed initiation of an efficient antimicrobial therapy after the first symptoms, diabetes, and coexistence of an osteoarticular location. Cardiovascular Campylobacter spp. infections are associated with a high mortality rate. Systematically searching for those localizations in cases of C. fetus bacteremia may be warranted.
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DOBA, IZUM, KILJ, NUK, ODKLJ, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Abstract
Although immune therapy of cancer, including immune-checkpoint blockade have demonstrated therapeutic benefit in patients with various advanced cancers, further understanding of human immune ...pathology triggered by the tumor microenvironment, is essential to improve these therapeutic approaches.
In order to shed light on novel immune suppressive mechanisms in tumor, iTeos Therapeutics developed a target discovery and drug repurposing platform based on phenotypic screening assays. We established a co-culture assay combining tumor immune suppressive cells and T-cells. This assay is flexible to allow the screening of chemicogenomics, shRNA and cDNA libraries. Multi-parameter readouts are combined to assess both T cell activation and proliferation, through high content imaging of T cell clusters formation, complemented with detection of IFNγ secretion and tumor cell death, as assessed using a cytotoxicity assay. The 96-well format of the assay allows medium-throughput testing of up to 3000 samples/screen. From the technical point of view we were able to adapt the assay to low level of automation, making it affordable to the biotech start-ups and academic laboratories.
As a proof-of-concept we evaluated the assay for its ability to detect metabolic immune-oncology targets in A549 cells, a lung cancer immune suppressive cell line. A549 express indoleamine-2,3-dioxygenase 1 (IDO1), an enzyme expressed in many cancers that mediates local T-cell suppression through depleting the essential amino acid tryptophan. The assay conditions were validated with an IDO1 inhibitor as positive control and subsequently scaled up for automation. A commercially available small molecule library of 1900 compounds, with a high percentage of clinically tested drugs was screened. The library was tested at two different concentrations (0.3μM and 3μM), with two independent T-cell donors and spiked with IDO1 inhibitor as control. Combined analysis of T-cell activity and tumor killing led to the identification of 42 compounds with activity on multiple, potential immune suppressive pathways, including metabolism, epigenetics, autophagy, TGFβ, Wnt/β-catenin and TNFα/NF-κB signaling.
Citation Format: Ariane Scoumanne, Virginie Rabolli, Lea Legrand, Murielle Martini, marie-claire Letellier, Stefano Crosignani, Christophe Quéva, Michel Detheux, Sandra Cauwenberghs, Jakub Swiercz. Development and validation of a screening platform for the identification of novel immuno-oncology targets abstract. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4612. doi:10.1158/1538-7445.AM2017-4612
Abstract
iTeos Therapeutics developed a target discovery and drug repurposing platform based on phenotypic screening assays that mimic the immunosuppressive tumor microenvironment. Here, we present ...an immunosuppressive cell line/T cell co-culture assay that enables chemical and genomic screening. Multi-parameter readouts are combined to assess both T cell activity as well as tumor cell death. T cell activity is measured through high content imaging of cluster formation complemented with detection of INFγ secretion. Tumor cell death is assessed using a cytotoxicity assay. The current format of the assay (96-well) allows medium-throughput testing of up to 3,000 samples/screen.
As proof-of-concept we evaluated the assay for its ability to detect metabolic immune-oncology targets like indoleamine-2,3-dioxygenase 1 (IDO1). IDO1 is expressed in a wide range of cancers and mediates local T cell suppression through depletion of the essential amino acid tryptophan. The assay conditions were validated with an IDO1 inhibitor as positive control and subsequently scaled up for automation. A commercially available small molecule library Selleck Bioactive Compound Library (cat number L1700), 1902 compounds with a high percentage of clinically tested drugs was screened. The library was tested at two different concentrations (0.3 μM and 3 μM), with two independent T cell donors and spiked with IDO1 inhibitors as internal control. The combined analysis of T-cell activity and tumor killing led to the identification of 42 compounds with activity on multiple, potential immune suppressive pathways, including metabolism, epigenetics, autophagy, and TGFβ signaling.
This assay is also suitable for gene modulation strategy using shRNA or cDNA libraries enriched for genes expressed specifically in immune suppressive cells and tissues. Moreover the assay can be adapted to additional cell types such as MDSC or Treg, opening up opportunities for identification of novel immune suppressive targets.
In conclusion, this approach allows rapid identification of mechanisms and targets contributing to tumor resistance. Phenotypic screens allow higher confidence in the selection of targets with a potential for clinical translation.
V.R., M.M., J.M.S., and S.C. contributed equally to this work.
Citation Format: Virginie Rabolli, Murielle Martini, Ariane Scoumanne, Marie-Claire Letellier, Stefano Crosignani, Christophe Quéva, Michel Detheux, Jakub M. Swiercz, Sandra Cauwenberghs. Development and validation of a phenotypic screening platform for the identification of novel immuno-oncology targets abstract. In: Proceedings of the Second CRI-CIMT-EATI-AACR International Cancer Immunotherapy Conference: Translating Science into Survival; 2016 Sept 25-28; New York, NY. Philadelphia (PA): AACR; Cancer Immunol Res 2016;4(11 Suppl):Abstract nr B030.
Abstract
Tumors use tryptophan-catabolizing enzymes such as Indoleamine 2,3-dioxygenase-1 (IDO-1) to induce an immunosuppressive microenvironment. IDO-1 expression is upregulated in many cancers and ...described to be a resistance mechanism to immune checkpoint therapies. IDO-1 is induced in response to inflammatory stimuli such as IFN-ã and promotes immune tolerance through the catabolism of tryptophan and accumulation of tryptophan catabolites including kynurenine. IDO-1 activity leads to effector T-cell anergy and enhanced Treg function through upregulation of FoxP3. As such, IDO1 is a nexus for the induction of key immunosuppressive mechanisms and represents an important immunotherapeutic target in oncology. We have identified and characterized a new IDO-1 inhibitor. PF-06840003 is a highly selective orally bioavailable IDO-1 inhibitor. PF-06840003 reversed IDO-1-induced T-cell anergy in vitro. In vivo, PF-06840003 reduced intratumoral kynurenine levels in mice by >80% and inhibited tumor growth in multiple preclinical syngeneic models in mice, in combination with immune checkpoint inhibitors. PF-0684003 has favorable predicted human pharmacokinetic properties, including a predicted t1/2 of 16-19 hours. These studies highlight the strong potential of PF-06840003 as a clinical candidate in Immuno-Oncology.
Citation Format: Joseph Tumang, Bruno Gomes, Martin Wythes, Stefano Crosignani, Patrick Bingham, Pauline Bottemanne, Hélène Cannelle, Sandra Cauwenberghs, Jenny Chaplin, Deepak Dalvie, Sofie Denies, Coraline De Maeseneire, Peter Folger, Kim Frederix, Jie Guo, James Hardwick, Ken Hook, Katti Jessen, Erick Kindt, Marie-Claire Letellier, Kai-Hsin Liao, Wenlin Li, Karen Maegley, Reece Marillier, Nichol Miller, Brion Murray, Romain Pirson, Julie Preillon, Virginie Rabolli, Chad Ray, Stephanie Scales, Jay Srirangam, Jim Solowiej, Nicole Streiner, Vince Torti, Konstantinos Tsaparikos, Paolo Vicini, Gregory Driessens, Manfred Kraus. PF-06840003: a highly selective IDO-1 inhibitor that shows good in vivo efficacy in combination with immune checkpoint inhibitors. abstract. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 4863.
Sialic acid has been sought as an excellent candidate for $\sp2$H NMR studies because of its ubiquitous presence at the penultimate non-reducing ends of membrane glycoproteins and glycolipids and ...because it has been associated with a number of biological and immunological phenomena. Regio- and stereoselectively deuteriated sialyl glycerolipids 1a, 1b and 1c were required for these studies and were synthesized.(DIAGRAM, TABLE OR GRAPHIC OMITTED...PLEASE SEE MAI) The first step of the synthetic route developed, involved the synthesis of unlabeled and labeled glycerolipids. The regio- and stereoselective deuterium incorporations in sialic acid and subsequent transformation of the deuteriated sialic acids into their respective glycosyl donors followed. The glycosylation of the glycerolipids with the appropriate glycosyl donors completed the synthesis of the model sialylglycerolipids and prompted further investigations of glycosidation methods for the synthesis of sialyl glycosides. A phase transfer catalysis procedure, particularly useful in the synthesis of thiosialosyl donors, was developed and the applicability of the procedure to produce a wide range of S- and O-sialosyl derivatives was explored. An extensive study of thioglycosylation reactions using a series of thiosialosyl donors, the glycerolipid and various thiophilic promoters resulted in the introduction of the concept of active and latent thiosialosyl donors which concluded the synthetic aspect of this research.
Soil microorganisms play key roles in ecosystem functioning and are known to be influenced by biotic and abiotic factors, such as plant cover or edaphic parameters. New Caledonia, a biodiversity ...hotspot located in the southwest Pacific, is one-third covered by ultramafic substrates. These types of soils are notably characterised by low nutrient content and high heavy metal concentrations. Ultramafic outcrops harbour diverse vegetation types and remarkable plant diversity. In this study, we aimed to assess soil bacterial and fungal diversity in New Caledonian ultramafic substrates and to determine whether floristic composition, edaphic parameters and geographical factors affect this microbial diversity. Therefore, four plant formation types at two distinct sites were studied. These formations represent different stages in a potential chronosequence. Soil cores, according to a given sampling procedure, were collected to assess microbial diversity using a metagenomic approach, and to characterise the physico-chemical parameters. A botanical inventory was also performed. Our results indicated that microbial richness, composition and abundance were linked to the plant cover type and the dominant plant species. Furthermore, a large proportion of Ascomycota phylum (fungi), mostly in non-rainforest formations, and Planctomycetes phylum (bacteria) in all formations were observed. Interestingly, such patterns could be indicators of past disturbances that occurred on different time scales. Furthermore, the bacteria and fungi were influenced by diverse edaphic parameters as well as by the interplay between these two soil communities. Another striking finding was the existence of a site effect. Differences in microbial communities between geographical locations may be explained by dispersal limitation in the context of the biogeographical island theory. In conclusion, each plant formation at each site possesses is own microbial community resulting from multiple interactions between abiotic and biotic factors.
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Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The use of web-based monitoring for lung cancer patients is growing in interest because of promising recent results suggesting improvement in cancer and resource utilization outcomes. It remains an ...open question whether the overall survival (OS) in these patients could be improved by using a web-mediated follow-up rather than classical scheduled follow-up and imaging.
Advanced-stage lung cancer patients without evidence of disease progression after or during initial treatment were randomly assigned in a multicenter phase III trial to compare a web-mediated follow-up algorithm (experimental arm), based on weekly self-scored patient symptoms, with routine follow-up with CT scans scheduled every three to six months according to the disease stage (control arm). In the experimental arm, an alert email was automatically sent to the oncologist when self-scored symptoms matched predefined criteria. The primary outcome was OS.
From June 2014 to January 2016, 133 patients were enrolled and 121 were retained in the intent-to-treat analysis; 12 deemed ineligible after random assignment were not subsequently followed. Most of the patients (95.1%) had stage III or IV disease. The median follow-up was nine months. The median OS was 19.0 months (95% confidence interval CI = 12.5 to noncalculable) in the experimental and 12.0 months (95% CI = 8.6 to 16.4) in the control arm (one-sided P = .001) (hazard ratio = 0.32, 95% CI = 0.15 to 0.67, one-sided P = .002). The performance status at first detected relapse was 0 to 1 for 75.9% of the patients in the experimental arm and for 32.5% of those in the control arm (two-sided P < .001). Optimal treatment was initiated in 72.4% of the patients in the experimental arm and in 32.5% of those in the control arm (two-sided P < .001).
A web-mediated follow-up algorithm based on self-reported symptoms improved OS due to early relapse detection and better performance status at relapse.
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