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Feucht, J.

Publications and source records attributed to Feucht, J..

4 recordsLinked to original sources

Repurposing passenger amplifications as Trojan horses identifies MPZL1 as a potent target for solid cancers

Personalized cancer therapies focus mostly on targeting driver alterations, such as oncogenic point mutations or oncogenic driver events within large somatic copy number alterations. However, these alterations are often not actionable or only present in a small subset of patients. We hypothesized that passenger events, specifically in amplified regions, could be therapeutically exploited by providing actionable molecules on the cell surface, serving as Trojan horses for specific therapy delivery. Applying a multiomics in silico approach, we identified MPZL1 (Myelin protein zero-like 1), a glycosylated cell surface receptor located on chromosome 1q, as a promising candidate, which is amplified in up to 75% of cases in several solid cancers. Notably, immunohistochemistry of a wide range of human cancer tissues (n=2244 samples) as well as normal tissues revealed strong membranous MPZL1 expression in a majority of solid tumors (e.g. 48% of hepatocellular carcinomas or 89% of triple-negative breast cancers), whereas healthy tissues were mostly negative or just faintly positive for MPZL1. Next, we generated a highly specific monoclonal antibody directed to the extracellular domain of human MPZL1 protein and utilized this antibody to produce MPZL1 CAR-T cells. MPZL1 CAR-T cells showed high specificity as well as high sensitivity in targeting a multitude of human cancer cell lines (e.g. liver, breast, and lung cancer) with high MPZL1 expression in vitro. Finally, we demonstrate strong therapeutic efficiency of MPZL1 CAR-T cells not only in different human xenograft tumors in vivo but also in a unique autochthonous liver cancer mouse model. Our work provides a framework to target passenger events within large chromosomal amplifications, reveals MPZL1 as a new trojan horse entry point for therapies of 1q-amplified cancers, and as such opens a new avenue for innovative approaches in anti-cancer drug development.

cancer biology↗

Dendritic cells accelerate CAR T cells in irradiated tumors through chimeric synapses

The persistence of adoptively transferred T cells is vital for anti-tumor efficacy. Chimeric antigen receptor (CAR) T cells can persist indefinitely when delivered to patients with B cell cancers and can confer long-term remission. For patients with solid tumors, however, sustaining CAR T cell activity remains a major challenge. This has been attributed in part to the immune microenvironment within solid tumors, though the contribution of specific immune subsets to resistance to CAR T cells is not clear. Here we resolve how the immunology of irradiated tumors dramatically enhances persistence and efficacy of CAR T cells targeted to advanced lung metastases in a syngeneic mouse model. Remarkably, CAR T cell persistence depended critically on dendritic cells (DC) that underwent trogocytic "antigen-dressing" of tumor target antigens and stimulated CAR T cells through the chimeric receptor. Furthermore, tumor irradiation increased antigen-dressing onto DCs. In the absence of functional DCs, CAR T cell activity in irradiated tumor was short-lived and tumors relapsed. These findings establish a critical mechanism through which DCs maintain the CAR T cell pool in irradiated tumors, thus supporting translation of this approach to advance CAR T cell therapy for solid tumors.

immunology↗

CAR-engineered lymphocyte persistence is governed by a FAS ligand/FAS auto-regulatory circuit

Chimeric antigen receptor (CAR)-engineered T and NK cells can cause durable remission of B-cell malignancies; however, limited persistence restrains the full potential of these therapies in many patients. The FAS ligand (FAS-L)/FAS pathway governs naturally-occurring lymphocyte homeostasis, yet knowledge of which cells express FAS-L in patients and whether these sources compromise CAR persistence remains incomplete. Here, we constructed a single-cell atlas of diverse cancer types to identify cellular subsets expressing FASLG, the gene encoding FAS-L. We discovered that FASLG is limited primarily to endogenous T cells, NK cells, and CAR-T cells while tumor and stromal cells express minimal FASLG. To establish whether CAR-T/NK cell survival is regulated through FAS-L, we performed competitive fitness assays using lymphocytes modified with or without a FAS dominant negative receptor ({Delta}FAS). Following adoptive transfer, {Delta}FAS-expressing CAR-T and CAR-NK cells became enriched across multiple tissues, a phenomenon that mechanistically was reverted through FASLG knockout. By contrast, FASLG was dispensable for CAR-mediated tumor killing. In multiple models, {Delta}FAS co-expression by CAR-T and CAR-NK enhanced antitumor efficacy compared with CAR cells alone. Together, these findings reveal that CAR-engineered lymphocyte persistence is governed by a FAS-L/FAS auto-regulatory circuit.

immunology↗

Somatic mouse models of gastric cancer reveal genotype-specific features of metastatic disease

Metastatic gastric carcinoma is a highly lethal cancer that responds poorly to conventional and molecularly targeted therapies. Despite its clinical relevance, the mechanisms underlying the behavior and therapeutic response of this disease are poorly understood owing, in part, to a paucity of tractable models that faithfully recapitulate different subtypes of the human disease. To close this gap, we developed methods to somatically introduce different oncogenic lesions directly into the stomach epithelium and show that genotypic configurations observed in patients produce metastatic gastric cancers that recapitulate the histological, molecular, and clinical features of all non-viral molecular subtypes of the human disease. Applying this platform to both wild-type and immune-deficient mice revealed previously unappreciated links between the genotype, organotropism and immune surveillance of metastatic cells that produced distinct patterns of metastasis that were mirrored in patients. Our results establish and credential a highly portable platform for producing autochthonous cancer models with flexible genotypes and host backgrounds, which can unravel mechanisms of gastric tumorigenesis or test new therapeutic concepts aimed at improving outcomes in gastric cancer patients.

cancer biology↗