Abstract 2912: High-throughput screening and single-cell transcriptomics identify synergies between oncology drugs and natural killer cell immunotherapy

Abstract Background & Objective: Natural killer (NK) cell-based immunotherapies are emerging therapeutic approaches that aim to target malignant cells resistant to conventional treatments and T cell-based immunotherapies. Existing oncology drugs may enhance the anti-cancer function of NK cells, although large-scale high-throughput testing of NK cell-drug combinations has not been previously attempted. Our objective was to evaluate the potential of approved and investigational oncology drugs to synergize with NK cell-based immunotherapy in acute myeloid leukemia (AML), with the aim to discover both potentiating and inhibiting compounds. Methods: A high-throughput drug sensitivity and resistance screen including 528 oncology drugs was combined with expanded NK cells to evaluate their cytotoxicity against luciferase-expressing AML cells (MOLM-14). The most prominent drugs were investigated further with single-cell RNA sequencing to reveal underlying biological mechanisms. Results: Overall, 191 drugs had an inhibitory effect on cytotoxicity, 294 had no effect, and 43 had an enhancing effect. The most notable NK cell cytotoxicity-potentiating drugs were pevonedistat (NEDD8 inhibitor), daporinad (NAMPT inhibitor), and JAK inhibitors. These drugs also induced distinct changes in NK and target cell transcriptional profiles. When combined with NK cells, pevonedistat and daporinad induced an upregulation of HLA-E and CXCL10 in target cells. In addition, MYC and FLT3 proto-oncogenes were downregulated in target cells when combining NK cells with pevonedistat. Moreover, in NK cells, daporinad induced dysregulated expression of genes related to NK cell effector functions such as TYROBP, TXNIP and KLRC1. Treatment with JAK inhibitors downregulated MHC I expression on target cells, providing a putative mechanism for increased NK cell activity. Validation of key hits is ongoing in additional AML cell lines. Conclusion: We discovered novel drugs with both potentiating and inhibiting effects on NK cell cytotoxicity against AML cells in vitro. Our results demonstrate the potential of using a high-throughput framework for studying NK cell-drug interactions against malignant cells, while aiming to improve treatment for AML and other malignancies through combination immunotherapies. Citation Format: Jonas O. Bouhlal, Petra Nygren, Essi Laajala, Aleksandr Ianevski, Jay Klievink, Hanna Lähteenmäki, Khalid Saeed, Dean Lee, Tero Aittokallio, Olli Dufva, Satu Mustjoki. High-throughput screening and single-cell transcriptomics identify synergies between oncology drugs and natural killer cell immunotherapy [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 2912.