Presentation entitled “TREM1+ CD163+ myeloid cells are potent immunosuppressive cells and associate with poor survival in human liver cancer”. Resume: “Hepatocellular carcinoma (HCC) is an inflammation-associated cancer arising from viral and non-viral etiologies. Expansion of suppressive myeloid cells is a hallmark of chronic inflammation and cancer, but their heterogeneity in HCC is not fully resolved and might underlie immunotherapy resistance. Here, we present a high resolution atlas of innate immunity cells in HCC and unravel remarkable myeloid cell heterogeneity and myeloid-biased NK cell differentiation. Among three phenotypically distinct subsets of myeloid-derived suppressor cells, we identify a discrete population of TREM1+CD163+ MDSC that expand in the inflamed liver and infiltrate HCC primary tumors. TREM1+CD163+ MDSC most potently suppress T cell activity ex vivo. They highly produce TGFbeta and are spatially enriched at fibrotic lesions in HCC. The density of TREM1+CD163+ MDSC correlate with poor patient survival and resistance to immune checkpoint blockade. Our data support myeloid subset-targeted immunotherapies to treat HCC”.

“Ancient origins of tumor-host interactions: insights from the Drosophila model.” The Bilder Lab (University of Berkeley, USA) studies the molecules and mechanisms that govern the polarity, growth, and morphogenesis of epithelia, the fundamental tissue of all animals and the major constituent of human organs. They also use Drosophila cancer models as a simple system to understand both how epithelial organization prevents tumor formation and how tumors actually kill their hosts. Example of recent work: Bilder et al., Tumour-host interactions through the lens of Drosophila, Nature Reviews Cancer (2021) There is a large gap between the deep understanding of mechanisms driving tumour growth and the reasons why patients ultimately die of cancer. It is now appreciated that interactions between the tumour and surrounding non-tumour (sometimes referred to as host) cells play critical roles in mortality as well as tumour progression, but much remains unknown about the underlying molecular mechanisms, especially those that act beyond the tumour microenvironment. Drosophila has a track record of high-impact discoveries about cell-autonomous growth regulation, and is well suited to now probe mysteries of tumour – host interactions. Here, we review current knowledge about how fly tumours interact with microenvironmental stroma, circulating innate immune cells and distant organs to influence disease progression. We also discuss reciprocal regulation between tumours and host physiology, with a particular focus on paraneoplasias. The fly’s simplicity along with the ability to study lethality directly provide an opportunity to shed new light on how cancer actually kills.

This workshop will explore cancer from an evolutionary perspective, with a strong focus on how cancer appeared and evolved and on the different forms of cancer across taxa. Speakers This workshop will gather the best world-leading experts on this issue: David Bilder (Berkeley, USA) Thomas Bosch (Kiel, Germany) James DeGregori (University of Colorado, USA) Mathieu Giraudeau (CNRS, La Rochelle, France) Vera Gorbunova (Rochester, USA) Crisanto Gutierez (Madrid, Spain) Hanna Kokko (Zürich, Switzerland) Carlo Maley (Arizona State University, USA) Elizabeth Murchison (Cambridge University, United Kingdom) Samir Okasha (University of Bristol, United Kingdom) Joshua D. Schiffman (University of Utah, USA) Flash talks – Bertrand Daignan-Fornier (IBGC, CNRS, Bordeaux, France) – Lucie Laplane (IHPST & Gustave Roussy, Paris, France) – Maël Lemoine (ImmunoConcept, University of Bordeaux, France) & Thomas Pradeu (ImmunoConcept, CNRS, France) – Benjamin Spada (ImmunoConcept, CNRS, France) Organizers – Bertrand Daignan-Fornier (IBGC, CNRS, Bordeaux, France) – Mathieu Giraudeau (LIENSs, CNRS, La Rochelle, France) – Thomas Pradeu (ImmunoConcept, CNRS, France) – Benjamin Spada (ImmunoConcept, CNRS, France) Venue Hôtel de la Plage, Arcachon, France 10, Avenue Nelly Deganne 33120 Arcachon, Tel. +33 (0)5 56 83 06 23; email: infos@hotelarcachon.com Further information : https://www.philinbiomed.org/event/arcachon-cancer-and-evolution/