Targeted Delivery of siRNA Using Chitosan-Based Nanoparticles for Suppressing Oncogene Expression in Cancer Cells

Abstract

The rise of nanomedicine offers novel strategies for cancer treatment, particularly through targeted gene therapy. This study investigates the efficiency of chitosan-based nanoparticles (CNPs) as carriers for small interfering RNA (siRNA) to specifically suppress the expression of a model oncogene (Bcl-2) in human cancer cells (MCF-7). CNPs were synthesized and characterized for size (targeting 145±15 nm), zeta potential (+18 ± 3 mV), and high siRNA encapsulation efficiency (85-90%). The in vitro delivery system demonstrated high cellular uptake, and treatment with CNP-siRNA complexes resulted in a significant, dose-dependent decrease in the target oncogene mRNA (68% reduction at 50 nM) and protein levels. This suppression was correlated with a marked reduction in cancer cell viability (IC₅₀ of 65 nM) and an increase in apoptosis. These findings suggest that CNP-mediated siRNA delivery is a promising, non-viral vector strategy for gene silencing, laying the groundwork for developing effective therapeutic agents against molecular targets in cancer.