ABSTRACT
Theranostic approach is currently among the fastest growing trends in cancer treatment. It implies the creation of multifunctional agents for simultaneous precise diagnosis and targeted impact on tumor cells. A new type of theranostic complexes was created based on NaYF4: Yb,Tm upconversion nanoparticles coated with polyethylene glycol and functionalized with the HER2-specific recombinant targeted toxin DARPin-LoPE. The obtained agents bind to HER2-overexpressing human breast adenocarcinoma cells and demonstrate selective cytotoxicity against this type of cancer cells. Using fluorescent human breast adenocarcinoma xenograft models, the possibility of intravital visualization of the UCNP-based complexes biodistribution and accumulation in tumor was demonstrated.
Subject(s)
Metal Nanoparticles/chemistry , Theranostic Nanomedicine , Animals , Breast Neoplasms/diagnostic imaging , Breast Neoplasms/drug therapy , Breast Neoplasms/pathology , Cell Line, Tumor , Cell Survival/drug effects , Female , Fluorescent Dyes/chemistry , Fluorides/chemistry , Humans , Metal Nanoparticles/therapeutic use , Metal Nanoparticles/toxicity , Mice , Mice, Nude , Polyethylene Glycols/chemistry , Receptor, ErbB-2/metabolism , Thulium/chemistry , Transplantation, Heterologous , Ytterbium/chemistry , Yttrium/chemistryABSTRACT
Upconversion nanoparticles (UCNPs) are new-generation photoluminescent nanomaterials gaining considerable recognition in the life sciences due to their unique optical properties that allow high-contrast imaging in cells and tissues. Upconversion nanoparticle applications in optical diagnosis, bioassays, therapeutics, photodynamic therapy, drug delivery, and light-controlled release of drugs are promising, demanding a comprehensive systematic study of their pharmacological properties. We report on production of biofunctional UCNP-based nanocomplexes suitable for optical microscopy and imaging of HER2-positive cells and tumors, as well as on the comprehensive evaluation of their pharmacokinetics, pharmacodynamics, and toxicological properties using cells and laboratory animals. The nanocomplexes represent a UCNP core/shell structure of the NaYF4:Yb, Er, Tm/NaYF4 composition coated with an amphiphilic alternating copolymer of maleic anhydride with 1-octadecene (PMAO) and conjugated to the Designed Ankyrin Repeat Protein (DARPin 9_29) with high affinity to the HER2 receptor. We demonstrated the specific binding of UCNP-PMAO-DARPin to HER2-positive cancer cells in cultures and xenograft animal models allowing the tumor visualization for at least 24 h. An exhaustive study of the general and specific toxicity of UCNP-PMAO-DARPin including the evaluation of their allergenic, immunotoxic, and reprotoxic properties was carried out. The obtained experimental body of evidence leads to a conclusion that UCNP-PMAO and UCNP-PMAO-DARPin are functional, noncytotoxic, biocompatible, and safe for imaging applications in cells, small animals, and prospective clinical applications of image-guided surgery.
Subject(s)
Mammary Neoplasms, Experimental/diagnostic imaging , Nanoparticles/chemistry , Polymers/chemistry , Whole Body Imaging/methods , Animals , CHO Cells , Cell Line, Tumor , Cricetulus , Drug Evaluation, Preclinical , Erbium/chemistry , Escherichia coli/genetics , Fluorides/chemistry , Humans , Luminescent Measurements , Nanoparticles/metabolism , Nanoparticles/toxicity , Polymers/pharmacokinetics , Polymers/toxicity , Receptor, ErbB-2/genetics , Surface Properties , Thulium/chemistry , Tissue Distribution , Yttrium/chemistryABSTRACT
We report combined therapy using upconversion nanoparticles (UCNP) coupled to two therapeutic agents: beta-emitting radionuclide yttrium-90 (90Y) fractionally substituting yttrium in UCNP, and a fragment of the exotoxin A derived from Pseudomonas aeruginosa genetically fused with a targeting designed ankyrin repeat protein (DARPin) specific to HER2 receptors. The resultant hybrid complex UCNP-R-T was tested using human breast adenocarcinoma cells SK-BR-3 overexpressing HER2 receptors and immunodeficient mice, bearing HER2-positive xenograft tumors. The photophysical properties of UCNPs enabled background-free imaging of the UCNP-R-T distribution in cells and animals. Specific binding and uptake of UCNP complexes in SK-BR-3 cells was observed, with separate 90Y- and PE40-induced cytotoxic effects characterized by IC50 140 µg/mL (UCNP-R) and 5.2 µg/mL (UCNP-T), respectively. When both therapeutic agents were combined into UCNP-R-T, the synergetic effect increased markedly, â¼2200-fold, resulting in IC50 = 0.0024 µg/mL. The combined therapy with UCNP-R-T was demonstrated in vivo.
