Abstract 5688: DSTYK dependent regulation of autophagy protects against TNF alpha induced apoptosis in lung cancer

Abstract The emergence of immunotherapy has significantly advanced the treatment of non-small cell lung cancer (NSCLC), yet acquired resistance remains a critical challenge. Understanding the molecular mechanisms behind tumor cell sensitivity to T-cell killing is essential to overcome resistance and improve treatment outcomes. Previous studies have indicated the roles of T cell-derived tumor necrosis factor-α (TNFα) and nuclear factor κB (NF-κB) signaling in tumor cell killing, with autophagy inhibiting TNF-α-induced apoptosis.Previous research in our lab has identified DSTYK, a dual serine/threonine and tyrosine kinase amplified in NSCLC, as a key regulator of mTOR. DSTYK plays a critical role in preventing TNF-α-mediated CD8+ T cell killing and impairs the response to immunotherapy in non-small cell lung cancer by inhibiting autophagy. However, the specific mechanism by which autophagy constrains TNF-α-dependent apoptosis remains unclear.In this study, we demonstrate that inhibition of DSTYK disrupts ULK1 phosphorylation, leading to RIPK1 autophosphorylation and promoting proapoptotic signaling through TNFR1 complex II. Furthermore, we demonstrated that ULK1 inhibition replicates the effects of DSTYK inhibition, reducing tumorigenic properties and sensitizing cells to apoptosis and necroptosis. In vivo experiments in syngeneic and xenograft mouse models corroborated these findings, showing significant tumor size reduction upon ULK1 inhibition. In conclusion, our study identifies DSTYK as a key regulator of the TNFR1 pathway via ULK1 phosphorylation, suggesting that targeting ULK1 could be a viable therapeutic strategy for sensitizing DSTYK-amplified NSCLC tumors to cell death. Citation Format: Andrea Pasquier, Cristina Viu-Idocin, Andrea Arricibita, Mirari Echepare, Beñat Picabea, Ane Álava, Joaquín Fernández-Irigoyen, Enrique Santamaría, Eva Molina, Antonio Pineda-Lucena, Luis Montuenga, Karmele Valencia. DSTYK dependent regulation of autophagy protects against TNF alpha induced apoptosis in lung cancer [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 5688.