Targeted TP53 and KRAS Modulation Via AuNP-Mediated RNA Delivery Suppresses Cancer Progression

Background: Small RNAs play a pivotal role in gene regulation, mediating RNAinduced transcriptional activation and post-transcriptional gene silencing. Their high specificity and versatility make them indispensable tools for investigating gene function, elucidating disease mechanisms, and developing targeted therapeutic strategies. Methods: We developed an AuNP-based RNA delivery system to enhance stability and uptake of therapeutic RNAs targeting TP53 and KRAS pathways. AuNPs were synthesized via citrate reduction and conjugated with siRNA.923 (KRAS-targeting siRNA) and dsP53-285 (p53-stimulating saRNA). A549 and HCT116 cells were transfected with conjugates. Gene expression was analyzed by RT-qPCR and Western blotting. Functional assays, including flow cytometry for cell cycle and apoptosis, MTT and colony formation assays for proliferation, and transwell assays for migration and invasion, were conducted. Results: Individual transfection of AuNP-conjugated siRNA.923 effectively downregulated KRAS expression, whereas AuNP-dsP53-285 upregulated TP53 expression in both A549 and HCT116 cell lines. Co-transfection with AuNP-siRNA.923/dsP53-285 resulted in a significantly greater increase in TP53 mRNA and protein levels, without affecting KRAS mRNA or protein levels, in both cell lines compared with individual transfections. Functionally, the AuNP-based dual small RNA delivery system induced cell cycle arrest at the G0/G1 phase, significantly enhanced apoptosis, and markedly reduced cell proliferation, colony formation, migration, and invasion relative to individual RNA transfections. Conclusion: These findings demonstrate that AuNP-mediated co-delivery of siRNA and saRNA effectively modulates the KRAS-p53 signaling axis and enhances therapeutic potential in KRASmutant, TP53-wild-type cancers. Further studies, including in vivo investigations, are warranted to evaluate the translational feasibility and clinical relevance of this combinatorial approach.