A Simple Add-and-Display Method for Immobilisation of Cancer Drug on His-tagged Virus-like Nanoparticles for Controlled Drug Delivery

Abstract

pH-responsive virus-like nanoparticles (VLNPs) hold promising potential as drug delivery systems for cancer therapy. In the present study, hepatitis B virus (HBV) VLNPs harbouring His-tags were used to display doxorubicin (DOX) via nitrilotriacetic acid (NTA) conjugation. The His-tags served as pH-responsive nanojoints which released DOX from VLNPs in a controlled manner. The His-tagged VLNPs conjugated non-covalently with NTA-DOX, and cross-linked with folic acid (FA) were able to specifically target and deliver the DOX into ovarian cancer cells via folate receptor (FR)-mediated endocytosis. The cytotoxicity and cellular uptake results revealed that the His-tagged VLNPs significantly increased the accumulation of DOX in the ovarian cancer cells and enhanced the uptake of DOX, which improved anti-tumour effects. This study demonstrated that NTA-DOX can be easily displayed on His-tagged VLNPs by a simple Add-and-Display step with high coupling efficiency and the drug was only released at low pH in a controlled manner. This approach facilitates specific attachment of any drug molecule on His-tagged VLNPs at the very mild conditions without changing the biological structure and native conformation of the VLNPs.

Targeted Delivery of Cell Penetrating Peptide Virus-like Nanoparticles to Skin Cancer Cells

“…These antigens represent potential sites for delivery of therapeutic agents 4 . Short ligands or peptides which can bind specifically to the active or biological relevant sites on target proteins can enhance the efficacy of tumour targeting therapy 16 , 17 . Studies on anti-cancer CPPs mostly focus on integrins due to their important roles in the initiation, progression and metastasis of tumours, which include the head and neck squamous cell carcinoma 10 , brain tumour 35 , 36 , hepatocarcinoma 37 , prostate cancer 38 , colon cancer 39 , and brain metastasis 40 .…”

“…To prove this hypothesis, truncated hepatitis B core antigen (tHBcAg) VLNPs were produced in Escherichia coli , purified, and used to display the CPP. These VLNPs have been employed to deliver green fluorescent protein (GFP), oligonucleotides and doxorubicin (DOX) into cancerous cells 7 , 15 – 17 . In the present study, this CPP was displayed on tHBcAg VLNPs via the nanoglue or a capsid binding peptide 7 .…”

A Dual Bioconjugated Virus-Like Nanoparticle as a Drug Delivery System and Comparison with a pH-Responsive Delivery System

“…This can be explained by the fact that the FR is highly expressed in HeLa and HT29 cancer cells [ 29 , 30 ], but it is lowly expressed in normal cells [ 28 , 31 ]. In addition, cancer cells overexpress the α-FR which has a high affinity to the free R-carboxylic acid of the conjugated FA molecules, whereas, normal cells mostly express the β-FR which has a higher binding affinity for 5-methyltetrahydrofolate, the reduced form of FA [ 32 ]. This is in line with our finding in which FA-tHBcAg-DOX VLNPs were taken up at much higher rates by the cancer cells (HeLa and HT29) than the normal cells (CCD-112 and 3T3).…”

“…The carboxylic acid groups of FA were activated by Sulfo-NHS and EDC, according to the method described by Biabanikhankahdani et al [ 32 ]. Then, the activated FA molecules were added to the solution of tHBcAg VLNPs in sodium phosphate buffer (100 mM Na 2 HPO 4 /NaH 2 PO 4 , pH 7.4), and the FA conjugated VLNPs were separated by sucrose density gradient (8%–40%, w / v ) as explained by Biabanikhankahdani et al [ 28 ].…”

“…HeLa (2.0 × 10 5 cell/mL), HT29 (2.0 × 10 5 cell/mL), 3T3 (1.0 × 10 5 cell/mL) and CCD-112 (1.0 × 10 5 cell/mL) cells were sub-cultured in six well plates. The old medium was then exchanged with 1 mL fresh medium containing FA-tHBcAg-DOX VLNPs, tHBcAg-DOX VLNPs, and free DOX with the equal DOX concentration (5 µg/mL), as described by Biabanikhankahdani et al [ 32 ]. The cells were fixed and imaged using the Olympus Live Cell Imaging (EX 480 nm and Em 535 nm).…”