siRNA-Encapsulated Hybrid Nanoparticles Target Mutant K-ras and Inhibit Metastatic Tumor Burden in a Mouse Model of Lung Cancer

There is an unmet need in the development of an effective therapy for mutant K-ras-expressing non-small-cell lung cancer (NSCLC). Although various small molecules have been evaluated, an effective therapy remains a dream. siRNAs have the potential to downregulate mutant K-ras both at the protein and mRNA levels. However, a safe and effective delivery of siRNAs to tumors remains a limitation to their translational application in the treatment of this highly debilitating disease. Here we developed a novel hybrid nanoparticle carrier for effective delivery of anti-mutant K-ras to NSCLC (AKSLHN). The ability of this treatment modality to regress lung tumors in mouse models was evaluated as a monotherapy or as a combination treatment with erlotinib. Further, the toxicity of this treatment modality to healthy tissues was evaluated, along with its ability to elicit immune/inflammatory reactions. The results suggest that this treatment modality is a promising prospect for the treatment of mutant K-ras-expressing NSCLC without any accompanying toxicity. However, further understanding of the cellular-level interaction between AHSLHN and erlotinib needs to be attained before this promising treatment modality can be brought to the bedside. Keywords: hybrid nanoparticles, siRNA, mutant K-ras, lung cancer, gene silencing, orthotopic model, human immunoglobulin G