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Targeting therapeutic agents to specific organs in the body remains a challenge despite advances in the science of systemic drug delivery. We have engineered a programmable-bioinspired nanoparticle (P-BiNP) delivery system to simultaneously target the bone and increase uptake in homotypic tumor cells by coating polymeric nanoparticles with programmed cancer cell membranes. This approach is unique in that we have incorporated relevant clinical bioinformatics data to guide the design and enhancement of biological processes that these nanoparticles are engineered to mimic. To achieve this, an analysis of RNA expression from metastatic prostate cancer patients identified ITGB3 (a subunit of integrin α V β 3 ) as overexpressed in patients with bone metastasis. Cancer cells were stimulated to increase this integrin expression on the cell surface, and these membranes were subsequently used to coat cargo carrying polymeric nanoparticles. Physicochemical optimization and characterization of the P-BiNPs showed desirable qualities regarding size, ζ potential, and stability. In vitro testing confirmed enhanced homotypic binding and uptake in cancer cells. P-BiNPs also demonstrated improved bone localization in vivo with a murine model. This novel approach of identifying clinically relevant targets for dual homotypic and bone targeting has potential as a strategy for treatment and imaging modalities in diseases that affect the bone as well as broader implications for delivering nanoparticles to other organs of interest.

Bone-metastatic prostate cancer symbolizes the beginning of the later stages of the disease. We designed a cabazitaxel-loaded, poly (lactic-co-glycolic acid) (PLGA) nanoparticle using an emulsion-diffusion-evaporation technique. Bis (sulfosuccinimidyl) suberate (BS3) was non-covalently inserted into the nanoparticle as a linker for the conjugation of a bone-targeting moiety to the outside of the nanoparticle. We hypothesized that the nanoparticles would have the ability to inhibit the epithelial-to-mesenchymal transition (EMT), invasion, and migration in prostate cancer cells. Targeted, cabazitaxel-loaded nanoparticles attenuated the EMT marker, Vimentin, and led to an increased E-cadherin expression. These changes impart epithelial characteristics and inhibit invasive properties in cancer progression. Consequently, progression to distant sites is also mitigated. We observed the reduction of phosphorylated Src at tyrosine 416, along with increased expression of phosphorylated cofilin at serine 3. These changes could affect migration and invasion pathways in cancer cells. Both increased p-120 catenin and inhibition in IL-8 expression were seen in targeted, cabazitaxel-loaded nanoparticles. Overall, our data show that the targeted, cabazitaxel-loaded nanoparticles can act as a promising treatment for metastatic prostate cancer by inhibiting EMT, invasion, and migration, in prostate cancer cells.

Treatment of metastatic Triple-Negative Breast Cancer (TNBC) remains a challenge despite an increasing number of newer drugs being approved in recent years. The major challenge for improved treatment outcomes for metastatic cancer originates from the fact that the drugs are unable to reach the targeted site and hence are not able to elicit the desired response. Recently, natural mesenchymal stem cells (MSC) cells and their exosomes have been shown to have tumor-homing properties. By exploiting these homing properties, we propose the development of an exosome-polymeric hybrid nanosystem (EPHN) by using exosomes for their targeting ability to enhance the targetability and thus the therapeutic efficacy of the drug against TNBC. In this study, we bioengineered MSC exosome-coated drug-loaded polymeric nanoparticles to deliver our chemotherapeutic drug in a targeted fashion. To isolate the MSC exosomes, we grew the cells in exosome-free media and used the ultracentrifugation standard method. The MSC exosomes had a size of approximately 70 ± 5 nm and a PDI of 0.3. Our exosome sample was positive for exosomal proteins and negative for all other extracellular vesicles. The optimal doxorubicin-loaded PLGA nanoparticles were prepared using a microfluidics method resulting in a higher entrapment efficiency of 42 ± 3% and a smaller size of 70 ± 3 nm and a PDI of 0.2. To make the exosome-coated NPs, we used the extrusion method. After extrusion, the zeta potential of our EPHN was closer to -11mV compared to PLGA NPs (-50mV), which demonstrates that our NPs were coated with an exosomal membrane. We were able to make MSC exosome-coated drug-loaded polymeric nanoparticles and show that they were stable and uniform in size. Microfluidics-assisted doxorubicin-loaded PLGA nanoparticles show uniform size and higher entrapment efficiency. Release kinetics showed a strong burst phase release over the first 8 hours and subsequent sustained release up to 72 hours. In vivo biodistribution of EPHN shows better tumor accumulation compared to PLGA NP. The next stage in this project is in vivo tumor efficacy testing in breast cancer tumor models. This targeted NP system can serve as a novel therapeutic platform for developing improved treatments for metastatic TNBC. Citation Format: Rohan Joshi, Jana Lampe, Jamboor K. Vishwanatha, Amalendu P. Ranjan. Exosome-based hybrid nanosystem for targeted TNBC therapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 832.

Rapid, Quantitative, Solvent-Free Synthesis of Medium-Ring Diaza Heterocycles from Diketene-Acetone Adduct and Diamines. -The remarkably efficient synthesis of biologically relevant diazepines, diazocines, and diazonines is also performed using conventional heating instead of microwave irradiation with virtually identical product yields after slightly longer reaction times. -(MORRISON, C. S.; LAMPE, J. B.; KOLODZIEJCZYK, T. C.; CAVAZOS, R. J.; PETROS*, R. A.; Tetrahedron Lett. 55 (2014) 48, 6547-6549, http://dx.