The Efficacy of Palbociclib-Conjugated ZnO-Ordered Mesoporous Carbon Nanohybrid against MCF-7 Breast Cancer Cell Line.

INTRODUCTION

Breast cancer is the most common cancer in females. The inhibitors of cyclin-dependent kinase 4/6 (CDK 4/6) have revolutionized the treatment of breast cancer. Palbociclib (Pal) is a highly potent CDK 4/6 inhibitor. The side effects and poor absorption of Pal may influence efficiency. This prompted us to conjugate Pal drug into the nanomaterial based on ZnO-ordered mesoporous carbon (ZnO-OMC) as a nanocarrier in drug delivery and investigate the anticancer activity of the Pal-conjugated ZnO-OMC (Pal@ZnO-OMC) on breast cancer cells (MCF-7).

METHODS

The ZnO-OMC composite was synthesized by the green method using Callicarpa plant extract, and Pal anticancer drug was loaded on the mentioned composite at different pHs, times, and ratios of drug to composite. The loading of Pal on ZnO-OMC composite was investigated by FE-SEM, UV-Vis, Raman, and FT-IR spectroscopy methods. The controlled Pal release from Pal@ZnO-OMC hybrid was investigated at different pH values and times. Moreover, the cytotoxicity of Pal@ZnO-OMC was evaluated on MCF-7 cells by MTT assay.

RESULTS

The results showed that ZnO-OMC is a highly efficient carrier with high loading of Pal, 82.5% at pH 7.0 for 3 h. The prepared Pal@ZnO-OMC exhibited favorable physico-chemical characteristics such as the controlled and targeted release pattern (15.2% of Pal is released at pH 7.4 for 10 h, while 58.1% of Pal is released at pH 4.0) and efficient cytotoxicity (cell viability of 50.4% and 38.8% at 24 and 48 h, respectively). Free Pal was significantly less efficient (with half-maximal inhibitory concentration (IC50) of 151.9 μg/mL for 48 h) than Pal@ZnO-OMC (with IC50 of 2.6 μg/mL for 48 h).

DISCUSSION: The synergistic effects of Pal@ZnO-OMC nanoformulation due to the presence of ZnO in hybrid seemed to improve antiproliferation efficacies against MCF-7 cells compared with the free Pal.

CONCLUSION

All findings demonstrated that the designed Pal@ZnO-OMC hybrid can be a potent nanoformulation for the treatment of MCF-7 breast cancer.