A versatile theranostic nanodevice based on an orthogonal bioconjugation strategy for efficient targeted treatment and monitoring of triple negative breast cancer

A novel chemical-based orthogonal bioconjugation strategy to produce tri-functionalized nanoparticles (NPs) an chemotherapy drug, doxorubicin (DOX), a near-infrared cyanine dye (Cy7) and CRGDK homing peptide, a peptide specifically binds to neuropilin-1 (Nrp-1) overexpressed on triple negative breast cancer (TNBC) cells, has been validated. These theranostic NPs have been evaluated in vitro and in vivo using an orthotopic xenotransplant mouse model using TNBC cells. In vitro assays show that theranostic NPs improve the therapeutic index in comparison with free DOX. Remarkably, in vivo studies showed preferred location of theranostic NPs in the tumor area reducing the volume at the same level than free DOX while presenting lower side effects. This multifunctionalized theranostic nanodevice based on orthogonal conjugation strategies could be a good candidate for the treatment and monitoring of Nrp-1 overexpressing tumors. Moreover, this versatile nanodevice can be easily adapted to treat and monitor different cancer types by adapting the conjugation strategy.

Tracking cell proliferation using a nanotechnology-based approach

AIM

To develop an efficient nanotechnology fluorescence-based method to track cell proliferation to avoid the limitations of current cell-labeling dyes.

MATERIAL & METHODS

Synthesis, PEGylation, bifunctionalization and labeling with a fluorophore (Cy5) of 200 nm polystyrene nanoparticles (NPs) were performed. These NPs were characterized and assessed for in vitro long-term monitoring of cell proliferation.

RESULTS

The optimization and validation of this method to track long-term cell proliferation assays have been achieved with high reproducibility, without cell cycle disruption. This method has been successfully applied in several adherent and suspension cells including hard-to-transfect cells and isolated human primary lymphocytes.

CONCLUSION

A novel approach to track efficiently cellular proliferation by flow cytometry using fluorescence labeled NPs has been successfully developed. [Formula: see text].

Cellular response to empty and palladium-conjugated amino-polystyrene nanospheres uptake: a proteomic study

Amino polystyrene nanospheres are shown to be efficient and controllable delivery devices, capable of transporting several bioactive cargoes. Recently, the design of a new device for prodrug activation, using these nanospheres with palladium encapsulated onto them, has been developed successfully. To study the influence of the cellular uptake of these nanodevices, we investigated the cellular response of human embryonic kidney cells (HEK-293T) and murine fibroblasts (L929) treated with empty or palladium-conjugated amino polystyrene nanospheres. To identify differentially expressed proteins, we performed an exhaustive proteomic analysis. In accordance with genomic data previously obtained, the uptake of the empty nanospheres did not induce significant variation in protein expression levels. Following the treatment with palladium-conjugated nanospheres, some changes in protein profiles in both cell lines were observed; these alterations affect proteins involved in cell metabolism and intracellular transport. No key regulator of the cell cycle result was differentially expressed after the treatment, confirming that these innovative drug delivery systems are harmless and well tolerated by the cells.

Cellular uptake of ribonuclease A-functionalised core–shell silica microspheres

Protein transduction: core–shell microspheres have been synthesised and coupled to ribonuclease A. Cellular uptake of these microspheres causes significantly reduced levels of intracellular RNA and reduced cell viability demonstrating that core–shell microsphere-mediated delivery of active enzymes into cells is effective.

In vitro nanoparticle-mediated intracellular delivery into human adipose-derived stem cells

Adipose-derived stem cells (ASCs) are multipotent cells that are emerging as an extremely promising therapeutic agent for tissue regeneration. The ability to manipulate ASC phenotypes by the delivery of biologically active cargoes is essential to understand their role and to design novel therapeutic strategies based on the use of ASCs. Here we describe a simple and efficient protocol for the conjugation and efficient delivery of biological materials into ASCs based on the use of polystyrene nanoparticles as carrier system.

The use of solid supports to generate nucleic acid carriers

Nucleic acids are the foundation stone of all cellular processes. Consequently, the use of DNA or RNA to treat genetic and acquired disorders (so called gene therapy) offers enormous potential benefits. The restitution of defective genes or the suppression of malignant genes could target a range of diseases, including cancers, inherited diseases (cystic fibrosis, muscular dystrophy, etc.), and viral infections. However, this strategy has a major barrier: the size and charge of nucleic acids largely restricts their transit into eukaryotic cells. Potential strategies to solve this problem include the use of a variety of natural and synthetic nucleic acid carriers. Driven by the aim and ambition of translating this promising therapeutic approach into the clinic, researchers have been actively developing advanced delivery systems for nucleic acids for more than 20 years. A decade ago we began our investigations of solid-phase techniques to construct families of novel nucleic acid carriers for transfection. We envisaged that the solid-phase synthesis of polycationic dendrimers and derivatized polyamimes would offer distinct advantages over solution phase techniques. Notably in solid phase synthesis we could take advantage of mass action and streamlined purification procedures, while simplifying the handling of compounds with high polarities and plurality of functional groups. Parallel synthesis methods would also allow rapid access to libraries of compounds with improved purities and yields over comparable solution methodologies and facilitate the development of structure activity relationships. We also twisted the concept of the solid-phase support on its head: we devised miniaturized solid supports that provided an innovative cell delivery vehicle in their own right, carrying covalently conjugated cargos (biomolecules) into cells. In this Account, we summarize the main outcomes of this series of chemically related projects.