Bovine Serum Albumin and Folic Acid-Modified Aurum Nanoparticles Loaded with Paclitaxel and Curcumin Enhance Radiotherapy Sensitization for Esophageal Cancer

Background: Nanocarrier systems have been used in the study of esophageal cancer (EC) and other diseases, with significant advantages in improving the non-targeted and non-specific toxicity of traditional formulations. Some chemotherapeutic drugs and high atomic number nanomaterials have sensitization effects on ionizing radiation and can be used as chemoradiation sensitizers. Methods: We selected bovine serum albumin (BSA) and folic acid (FA)-modified aurum (Au) nanoparticles, which were core-loaded with paclitaxel (PTX) and curcumin (CUR). The basic characteristics of FA-BSA-Au@PTX/CUR nanomedicines were evaluated by transmission electron microscopy, Fourier transform infrared spectroscopy, and Malvern Zetasizer. The encapsulation and release of drugs were tracked by ultraviolet-visible spectrophotometry (UV-Vis). The biological toxicity and radiotherapy sensitization effect of FA-BSA-Au@PTX/CUR were observed by cell viability, colony formation, cell apoptosis, cell cycle distribution, and γ-H2AX analysis experiments. Results: The prepared nanomedicines showed good stability and spherical morphology. The results of cell uptake and cell viability detection showed that FA-BSA-Au@PTX/CUR could specifically target EC cell KYSE150 and exert a certain inhibitory effect on proliferation, without obvious toxicity on healthy cells Het-1A. In addition, the results of colony formation experiment, cell apoptosis detection, cell cycle distribution, and γ-H2AX analysis showed that compared with X-rays alone, FA-BSA-Au@PTX/CUR combined with X-rays exhibited relatively stronger radiotherapy sensitization and anti-tumor activity. Conclusion: FA-BSA-Au@PTX/CUR could target EC cancer cells and could be used as a safe and effective radiotherapy sensitizer to improve the radiotherapy efficacy of EC.