Abstract 6953: Inhibition of Eukaryotic elongation factor 2 kinase (eEF2K) disrupts key processes in colorectal cancer progression and tumor growth

Abstract Colorectal cancer (CRC) is the third most commonly diagnosed cancer with 1.9 million new cases and the second leading cause of cancer-related deaths, with 935, 000 deaths reported in 2023. Despite advances in therapy, the 5-year survival rate for metastatic CRC remains as low as 14%, emphasizing the need for novel treatment strategies. Previously, we have validated that Eukaryotic elongation factor 2 kinase (eEF2K) is an atypical alfa kinase as a potential molecular target that is commonly expressed in highly aggressive solid cancers such as triple-negative breast cancer, pancreatic, ovarian, and lung cancers and demonstrated that it acts as a key player in the survival, proliferation, invasion, and tumor growth of cancer cells and promoting cell. In this study, we investigated the role of eEF2K in colon cancer tumorigenesis and progression and its potential as a therapeutic target using a novel eEF2K small molecule inhibitor and siRNA-based knockdown studies. We found that eEF2K expression is highly expressed in CRC cell lines and eEF2K is associated with shorter patient survival and poor prognostic marker in CRC patients (NCI-TCGA patient database), inhibition of eEF2K in various CRC cell lines (HCT116, RKO, COLO320, and with different genetic alterations leads to suppression on cell proliferation, migration, and invasion. Western blot analysis confirmed that treatment with the siRNA and the eEF2K inhibitor reduced the activity of clinically significant signaling molecules including Src, FAK, and Cyclin D1 which are crucial for tumor growth and progression. In vivo, targeting of eEF2K by eEF2K siRNA encapsulated in iron oxide nanoparticles (IONPS) and our novel water soluble small-molecule eEF2K inhibitor suppressed CRC tumor growth of HTC116 and RKO tumors (flank) CRC tumor models in nude mice, with no observed toxicity. Analysis of tumor tissues by immunohistochemistry showed significant inhibition of the Ki-67 proliferation marker and induction of apoptosis by TUNEL staining. Our study provides the first evidence that eEF2K is a clinically significant potential molecular target and contributes to tumorigenesis and progression of CRC. Its effective inhibition is safe and can suppress tumor growth in preclinical CRC models. These promising results lay the foundation for further developing eEF2K-targeted therapies, offering a potential new approach for treating CRC. Citation Format: Nermin Kahraman, Ezgi Biltekin, Ogun Ali Gul, Goknur Kara, Izabela Fokt, M. Akay Yasemin, Waldemar Priebe, Metin Akay, Bulent Ozpolat. Inhibition of Eukaryotic elongation factor 2 kinase (eEF2K) disrupts key processes in colorectal cancer progression and tumor growth [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 1 (Regular Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_1):Abstract nr 6953.