Systemic drug co-delivery system with miR-34a and doxorubicin assembled by layer-by-layer (LbL) for osteosarcoma treatment

Osteosarcoma is a primary malignant bone tumor with elevated mortality rates in youngsters and adolescents. Current therapeutic approaches entail preliminary chemotherapy followed by surgical removal and supplementary chemotherapy. Roughly 30% of patients experience recurrence, underscoring the limitations, as surgery alone cannot effectively manage metastasis. Nanoparticle-mediated targeted drug delivery systems present a promising therapeutic avenue for osteosarcoma, as they overcome the constraints of conventional chemotherapy by augmenting retention, permeability, and active targeting. Objectives Devise and construct systemic drug co-delivery systems by utilizing nanoscale modification of miR-34a and doxorubicin via layer-by-layer (LbL) assembly for precise osteosarcoma treatment. Approaches PLGA-CS polyplexes were produced using optimized nano-complexation and LbL assembly techniques. LbL-NPs were examined on two-dimensional SaoS-2 and U2OS cell models to gauge metabolic activity and cellular demise via PrestoBlue and Live/dead assessments. Encapsulation efficiency and drug release kinetics were appraised using the QuantiFluor® RNA System and UV-VIS Spectroscopy. Findings Manufactured PLGA-CS polyplexes exhibited impressive mean encapsulation efficiencies for miR-34a and doxorubicin, 99.97% and 69.74%, respectively. Only the fabricated LbL-NPs P4 and PC4 displayed substantial, sustained release of miR-34a over a ten-day period (P-value 0.002 and 0.011). All LbL-NPs, at concentrations of 500 and 1000µg/ml, markedly diminished the metabolic activity of U2OS cells after five days of incubation (P-value <0.001). LbL-NPs P5 and PC5 induced apoptotic activity and cell demise in U2OS cells. Conclusion The engineered PLGA-CS polyplexes and LbL-NPs serve as effective nanocarrier systems, inducing cytotoxicity by delivering tumor-suppressing miR-34a and doxorubicin into in vitro osteosarcoma cell models. The incorporation of hyaluronic acid and additional nanocoating further enhances the cytotoxicity of LbL-NPs against U2OS cells through active targeting.