Use of nanoemulsion for co-delivery of silibinin and cabazitaxel for prostate cancer treatment.

OBJECTIVE

This study introduces a novel nanoemulsion (NE) system co-loaded with silibinin (SIL) and cabazitaxel (CBX) to address limitations, such as poor solubility, low bioavailability, and systemic toxicities of these agents.

SIGNIFICANCE: SIL/CBX-loaded NE enhances the anticancer effects of SIL/CBX against prostate cancer (PCa) in vitro and in vivo, while it could simultaneously reduce the systemic toxicity of SIL/CBX.

METHODS

The NE-SIL/CBX was prepared using oleic acid as the oil phase, Tween-80 and Cremophor RH40 as the surfactants, and Transcutol HP as the cosurfactant.

RESULTS

The optimized NE formulation exhibited a particle size of 204.30 ± 10.20 nm, an encapsulation efficiency exceeding 95.30%, and sustained stability under biological and storage conditions. In vitro studies demonstrated a 6.80-fold improvement in cytotoxicity against PCa cells (IC50 = 6.30 µM) compared to the free SIL/CBX combination, while maintaining 62.10% cell viability in normal cells (HEK293) at 100 µg/mL, indicating reduced off-target toxicity compared to free SIL/CBX combination. In vivo, NE-SIL/CBX reduced tumor volume by 78.90% and tumor weight by 80.00% while maintaining stable liver and kidney function, highlighting its safety. The formulation's controlled drug release (87.60% of drug release for SIL and 78.50% of drug release for CBX after 72 h) and synergistic therapeutic effects significantly (p ˂ 0.05) enhanced efficacy compared to free SIL and CBX.

CONCLUSION

These findings establish NE-SIL/CBX as a promising platform for PCa treatment, offering improved therapeutic index and reduced systemic toxicity. Future clinical investigations could validate its potential for precision oncology applications.