Pseudomonas aeruginosa Peptide From Strain P3 ( PAP3 ) and AKT Serine/Threonine Kinase 1 ( AKT1 ) siRNA‐Loaded Chitosan Nanoparticle as a Co‐Delivery System for Enhanced Anticancer Activity in Lung Cancer Cells

Multidrug-resistant tumor cells pose significant challenges in cancer treatment. Alternative strategies such as targeted gene silencing and the use of compounds with minimal cytotoxicity toward normal cells are therefore of great interest. Antimicrobial peptides (AMPs) have demonstrated anticancer potential due to their physicochemical properties. In lung cancer, overexpression of AKT serine/threonine kinase 1 (AKT1) promotes abnormal tumor growth and progression. In this study, we synthesized chitosan-based nanoparticles (CSNPs) co-loaded with Pseudomonas aeruginosa peptide from strain P3 (PAP3) (an AMP) and siRNA targeting the AKT1 gene, and evaluated their anticancer activity at the cellular and molecular levels. Characterization of the CSNPs revealed a nanoscale structure, low polydispersity index, and moderate encapsulation efficiency for both peptide and siRNA. Evaluation using L929 cells confirmed PAP3's nontoxic profile, while a dose-dependent anticancer effect against A549 cells was observed. Delivery of encapsulated peptide, siRNA, and their combination increased cell death and induced morphological changes in A549 cells. Gene expression analysis showed upregulation of pro-apoptotic markers (Bax and Caspase-3) and downregulation of the anti-apoptotic marker Bcl2, indicating promising anticancer properties of the engineered compound. In conclusion, co-delivery of PAP3 and AKT1-targeting siRNA via CSNPs demonstrates potential for future anticancer therapies.