Demonstration of SLU7 as a new pan-cancer target

Cancer treatment remains challenging due to heterogeneous responses to immunotherapy across patients and tumor types. Innovative strategies are required to overcome immune evasion. We have identified the splicing factor SLU7 as essential for the survival of cancer cells from diverse origins. SLU7 knockdown induces R-loop accumulation, transcription-dependent genomic instability, DNA damage, and replication catastrophe, together with aberrant splicing and inhibition of nonsense-mediated mRNA decay (NMD) and/or DNA methylation. These alterations lead to the expression of neoantigens, interferon B1, endogenous retroviruses, and cancer-testis antigens, which would enhance tumor immunogenicity. Therefore, we propose SLU7 targeting as a dual-action therapy, combining direct tumor suppression with immune activation. Using various murine cancer models, including orthotopic liver tumors, and multiple molecular strategies--such as inducible CRISPR/Cas9, systemic delivery of chimeric siSLU7-nucleolin aptamers (APTASLU), and intratumoral injection of siSLU7-loaded nanoparticles--we show that distinct siSLU7 sequences and delivery platforms effectively inhibit tumor growth. Furthermore, SLU7 silencing synergizes with immune checkpoint inhibitors, amplifying anti-tumor responses. Our in vivo data demonstrate that SLU7 is a promising, versatile target for diverse cancers. Its multimodal mechanism offers potential to overcome tumor heterogeneity, reverse immune tolerance, and enhance immunotherapy efficacy.