Genome-Wide CRISPR Screen Reveals PIK3CA Inhibition Enhances Lipid Nanoparticle-Mediated siRNA Delivery.

Lipid nanoparticles (LNPs) are useful carriers for therapeutic siRNA delivery, yet their clinical efficacy remains constrained by insufficient cellular uptake. Here, using a genome-wide CRISPR knockout screen, multiple genetic modulators of LNP uptake is uncovered, with PIK3CA emerging as a top druggable target. Pharmacologic inhibition of PIK3CA with BAY1082439 - a clinically evaluated small molecule - significantly enhances LNP uptake, siRNA delivery, and gene silencing across diverse epithelial cancer cell lines in vitro. Co-administration of BAY1082439 with siRNA-loaded LNPs also better suppressed tumor growth and reduced liver inflammation in vivo, respectively. These findings establish PIK3CA inhibition as a broadly applicable strategy to boost LNP-mediated RNA interference and highlight the promise of combining functional genomics with nanomaterials to advance RNA-based therapeutics.