CAR-based cell therapies have revolutionized cancer treatment, however, applications beyond targeting lineage antigens are challenging due to expression of targeted antigens in healthy cells posing a risk for on-target off-tissue toxicities. This presents an opportunity to leverage synthetic biological logic gated gene circuits, such as NOT gate, to expand cancer targets for CAR-based cell therapies. We have constructed a first-in-class NOT gate in CAR-NK cells to protect healthy cells from CAR-mediated cytotoxicity. An inhibitory CAR (iCAR) recognizes a safety antigen expressed on healthy cells and suppresses activating CAR (aCAR) functions, significantly reducing NK cell activity. Multiple iCARs with intracellular co-inhibitory domains containing immunoreceptor tyrosine-based inhibitory motifs have shown to suppress over 50% of aCAR-mediated killing (p<0.05) and significantly reduce TNFa secretion (p<0.0005) in an antigen-specific manner. Here we describe a robust cancer and safety antigen pairing discovery method for the development of NOT gated CAR-NK therapies. A bioinformatics pipeline uses transcriptomics data to discover and prioritize tumor and healthy tissue antigens. We have identified genes differentially expressed in healthy vs tumor tissue and selected leads based on antigens' co-expression in healthy tissue, subcellular localization, antigen topology (presence of extracellular domain(s)), and antibody availability. Such antigen pairs have been validated in primary tissue samples. In AML, targeting the critical leukemic stem cell (LSC) population via antigens such as FLT3 leads to hematopoietic toxicity due to expression in healthy hematopoietic stem cells (HSCs). Comparative bioinformatic analysis between AML and healthy human bone marrow mononuclear cell (BMMC) samples identified 10 surface antigens differentially expressed between HSCs and AML cells that could be used as NOT gate targets to protect HSCs from CAR-mediated toxicity. We further validated one of the top candidate targets, EMCN, by flow cytometry and confirmed significant differential protein expression between HSCs and LSCs. Similarly, in CEA+ tumors, significant on-target off-tissue toxicities occur in healthy epithelium resulting in colitis and lung damage. We prioritized 3 healthy tissue antigens preferentially expressed in intestinal and lung epithelial cells compared to cancer cells: VSIG2, CPM and SLC26A2. IHC analysis confirmed that these targets are expressed at higher levels in the healthy tissues compared to CEA+ tumor, making them attractive candidates to use in a NOT gate circuit to improve the therapeutic window of CEA CAR-NK cells. Using a bioinformatics discovery and validation pipeline coupled with NOT logic gated CAR-NK cells, we can selectively target tumor antigens, while protecting healthy tissues, to create cell therapies with greater efficacy, precision and control. Citation Format: Alba Gonzalez, Assen Roguev, Nicholas W. Frankel, Brian S. Garrison, Derrick Lee, Marcus Gainer, Alyssa Mullenix, Russell M. Gordley, Kathryn A. Loving, Jenny Chien, Gary Lee. Development of logic-gated CAR-NK cells to reduce target-mediated healthy tissue toxicities [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr LB028.
While immunotherapies based on single recombinant cytokines such as IL12 and IL21 have shown great promise in preclinical models of solid tumors, clinical translation has proven challenging due to limited mechanisms of action, narrow therapeutic windows upon systemic administration, and short half-lives resulting in poor pharmacokinetics and distribution. Thus, there is a need for tumor-localized cytokine therapies capable of driving sustained efficacy with a wide therapeutic window. SENTI-101 is a cell-based immunotherapy comprising allogeneic bone marrow-derived mesenchymal stromal cells (BM-MSCs) genetically modified to express IL12 and IL21. Consistent with prior studies, we demonstrated that SENTI-101 innately homes to disseminated tumors in the peritoneal cavity and induces durable anti-tumor responses and immune memory in various preclinical models of peritoneal tumors. In this study, we investigated the mechanisms of action of SENTI-101. Our results demonstrate that the IL12 and IL21 combination elicits pleiotropic and complementary effects that drive a multi-modal immune response across various steps of the cancer immunity cycle. Treatment of preclinical murine models of peritoneal tumors (e.g., CT26 and B16F10) with SENTI-101 significantly increased the local production of IFNg by more than 40-fold (p<0.02). Concurrently, mice treated with SENTI-101 had significantly increased levels of cytokines and chemokines such as CXCL9 (p<0.02), which have previously been associated with better prognosis and response to immunotherapy in multiple cancer types. We used flow cytometry and multiplexed IHC to characterize the immune landscape in response to SENTI-101. The number of antigen-presenting cells (F4/80negCD11c+MHC-II+CD103+) more than doubled in peritoneal lymph nodes 72 h after treatment with SENTI-101 (p=0.016). We also observed an increase in pSTAT1 positivity in the myeloid compartment, indicating a favorable immune phenotype. This change was accompanied by an increase in T-cell infiltrates into tumors (p=0.0003) that were in close proximity with B-cells and that were organized in tertiary lymphoid structures, which are known to correlate with improved prognosis in cancer patients. T-cell activation markers (CD38, CD25, IFNg, GranzymeB) also increased by more than 6 times (p=0.015) in the tumor microenvironment (TME) and peritoneal fluid after treatment with SENTI-101. In accordance with increased T-cell infiltration and activation in the TME, SENTI-101 showed a synergistic anti-tumor effect when combined with checkpoint inhibitor anti-PD1. Overall, our preclinical studies show that SENTI-101 modulates the tumor immune landscape via multiple complementary modes of action, resulting in long-term anti-tumor immunity. Furthermore, this work demonstrates the therapeutic potential of tumor-localized cell therapies armed with gene circuits expressing combinatorial immune effectors to trigger a multi-factorial anti-tumor response. Citation Format: Alba Gonzalez, Frances D. Liu, Archana Nagaraja, Alyssa Mullenix, Russell M. Gordley, Daniel O. Frimannsson, Anissa Benabbas, Chen-Ting Lee, Tiffany A. Truong, Allison Quach, Mengxi Tian, Rowena Martinez, Rishi Savur, Alyssa Perry-McNamara, Don-Hong Wang, Ori Maller, Dharini Iyer, Ashita Magal, Sravani Mangalampalli, Christina J. Huynh, Carmina C. Blanco, Jack T. Lin, Brian S. Garrison, Philip Lee, Timothy K. Lu, Gary Lee. SENTI-101, a novel genetically modified allogeneic cell product expressing IL12 and IL21, elicits a tumor-localized, robust, and multimodal immune response in preclinical models of solid tumors [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 4246.
Gliomas are the most common primary tumors affecting the adult human Central Nervous System (CNS). The most lethal is grade IV glioblastoma (GBM), which gives a median survival of only 15 months, but less severe grades also respond poorly to standard therapy. Myc is a bHLHZip transcription factor, causally implicated in most human tumors. In the past, we employed a dominant negative of Myc transactivation activity, termed Omomyc, and we showed that Myc inhibition is a potent strategy in cancer therapy, both in K-RasG12D-driven lung tumors and in T antigen-driven pancreatic β-cell insulinomas. Now, we make use of a mouse model of Ha-Ras driven glioma coupled with our Omomyc switchable model in order to assess Myc inhibition as a therapeutic strategy in glioma. Myc inhibition has a dramatic therapeutic impact in the animals, being able to both prevent formation and cause regression of tumors. We also tested neuroprogenitor cells derived from the same animal model as putative cells of origin of glioma. In this context, Myc inhibition reduced proliferation, increased death and impaired the self-renewal of Ha-Ras transformed neuroprogenitors. Similar results were obtained with human glioblastoma cell lines, which presented severe mitotic catastrophe as a consequence of Omomyc expression, revealing a new Achilles’ heel of glioblastoma. Finally, Myc inhibition was tested in orthotopic xenografts using patient-derived tumor samples and showed once again dramatic therapeutic impact, conferring a significant survival advantage to recipient animals. Conclusion: Myc inhibition is a potent therapeutic strategy in glioma and its effects include induction of mitotic crisis in tumor cells. Citation Format: Daniela Annibali, Jonathan R. Whitfield, Emilia Favuzzi, Toni Jauset, Erika serrano, Gerard Folch, Marta I. Cuartas, Alba Gonzalez, Lamorna Brown Swigart, Sergio Nasi, Gerard I. Evan, Joan Seoane, Laura Soucek. MYC inhibition is a potent therapy against glioma and induces mitotic crisis in cancer cells. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 1085. doi:10.1158/1538-7445.AM2013-1085
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.