Synergistic Effect of Tangeretin and Atorvastatin for Colon Cancer Combination Therapy: Targeted Delivery of These Dual Drugs Using RGD Peptide Decorated Nanocarriers

Abstract

Purpose

Colorectal cancer (CRC) is the third most frequently diagnosed cancer and the fourth leading cause of cancer death over the world. Nano-sized drug delivery systems are used for the treatment of cancers. The aim of this study was to develop a tangeretin (TAGE) and atorvastatin (ATST) combined nano-system decorated with RGD (RGD-ATST/TAGE CNPs) for colon cancer combination therapy.

Materials and Methods

In this study, cyclized arginine-glycine-aspartic acid sequences (RGD) contained ligand was synthesized by conjugating cyclo (Arg-Gly-Asp-d-Phe-Lys) (cRGDfK) with D-α-tocopheryl succinate dichloromethane (TOSD) using polyethylene glycol (PEG) as a linker to obtain cRGDfK-PEG-TOSD. ATST and TAGE combined nano-systems: RGD-ATST/TAGE CNPs were prepared. The combination effects as well as antitumor effects of these two agents were evaluated on colon cancer cells and mice bearing cancer models.

Results

Drug entrapment efficiencies of nano-systems were high (around 90%), suggesting the good loading capacity. The release profiles of ATST or TAGE from RGD-ATST/TAGE CNPs followed Higuchi model. The RGD-decorated nano-system showed more obvious cytotoxicity on HT-29 cells than the undecorated nano-system, but no obvious difference was found on normal CCD-18 cells. The strongest synergism was observed when the weight ratio of ATST to TAGE was 1:1. In vivo biodistribution of RGD-ATST/TAGE CNPs in the tumor site is high and prominently inhibited the in vivo tumor growth.

Conclusion

The results demonstrated that RGD-ATST/TAGE CNPs showed the most significant synergistic therapeutic efficacy, exhibited no significant toxicity to major organs and tissues, and body weight of the treated mice was stable. Therefore, the combination nano-system is a promising platform for colon cancer therapy.

Keywords:

• colorectal cancer
• tangeretin
• atorvastatin
• nanoparticles
• cytostatic anticancer agents

Funding

This research was funded by the Natural Science Basic Research Program of Shaanxi Province (Program No. 2020JQ-932).

Abbreviations

ATST, atorvastatin; ATST LNPs, ATST loaded lipid nanoparticles; ATST/TAGE CNPs, ATST and TAGE combined nano-systems; CBP, Carbopol 940; CI, combination index; CRC, colorectal cancer; cRGDfK, cyclo (Arg-Gly-Asp-d-Phe-Lys); DCC, dicyclohexylcarbodiimide; DMEM, Dulbecco’s modified Eagle’s medium; FBS, Fetal bovine serum; GMS, glyceryl monostearate; ¹H NMR, nuclear magnetic resonance; MDR, multidrug resistance; MTT, 3-(4,5-dimethylthiazole-2-yl)−2,5-diphenyltetrazolium bromide; NCCN, National Comprehensive Cancer Network; PEG, polyethylene glycol; RGD, cyclized arginine-glycine-aspartic acid sequences; RGD-ATST/TAGE CNPs, RGD modified, ATST and TAGE combined nano-systems; RGD CNPs, blank RGD modified, ATST and TAGE combined nano-systems; TAGE, tangeretin; TOSD, D-α-tocopheryl succinate dichloromethane; TAGE ZNPs, TAGE loaded zein nanoparticles.

Disclosure

The authors report no conflicts of interest in this work.