(M1030-03-17) Development of Monocarboxylate Transporter 4 Inhibitor/Docetaxel-Loaded Smart Layer-By-Layer Nanoparticles for Prostate Cancer Therapy

Purpose: Prostate Cancer is the second leading cause of death in the United States of America. In advanced prostate cancer, anaerobic glycolysis increases, leading to excessive production of lactic acid. Monocarboxylate transporters (MCT4) play a crucial role in maintaining the hyper-glycolytic acid-resistant phenotype of prostate cancer by facilitating lactate efflux. Inhibition of MCT4 by an MCT4 inhibitor (MCT4i, AZD0095) increases prostate cancer cells’ intracellular pH, ultimately leading to prostate cancer cell death. Little is known about the anti-prostate cancer properties of the compound AZD0095, a promising MCT4i.  Docetaxel(DXT) is one of the few options to treat advanced prostate cancer when androgen deprivation therapy has failed. The proposed work seeks to develop and characterize a MCT4i/DXT-loaded poly(lactide-co-glycolide) Acid (PLGA), a smart layer-by-layer (LBL) Nanoparticle for prostate cancer combination therapy.

Methods: The core of the LBL smart NPs is prepared by nanoprecipitation and subsequently freeze-dried. This freeze-dried nanoparticle is a common PLGA nanoparticle (F).Then, the LBL smart nanoparticle shell is engineered by resuspending the freeze-dried NPs in a potential Prostate Specific Membrane Antigen (PSMA) ’ligand ( i.e ethylphenyl phosphinate) aqueous solution of sodium acetate and freeze-dried for the second time. This nanoparticle is the layer-by-layer (LBL) smart nanoparticle (SF). The different nanoformulation parameters are shown in Table 1. The physicochemical properties of the different nanoparticles(i.e, Particle Mean Diameter, zeta potential, percent weight, and surface chemistry of the nanoparticle were characterized by Advanced ZetaSizer, UV/VIS Spectrophotometer, and Infrared spectrometer (FT-IR). The cytotoxicity of the different formulations on C4-2, a castration resistance Prostate cancer cell line, is assessed by MTS assay.

Results: The particle’s mean diameters (PMD) range from 153.8±6 nm to 2341.0 nm. The PMD of F3 and SF3 is 559.1±16 nm and 260.4±38 nm. The PMD of all smart nanoformulations (SF) are less than that of common PLGA nanoparticles (F). The size distribution by intensity of all nanoformulations is shown in Fig.1. The FTIR confirms that sodium acetate coats all the nanoformulations. Based on ISO10993-5 for cell viability, with 100%viability assigned to the control, the blank PLGA NPs (B1) and blank Smart acetate layer-by-layer NPs (SB1), which do not contain any drug, are not cytotoxic to the C4-2 cells. As expected, the Smart layer-by-layer MCT4i/DTX-loaded PLGA NPs are strongly cytotoxic to the C4-2.cells. The C4-2 cell growth when exposed to both F3 and SF3 nanoformulations is 34.78±7.74% and 31.17±8.13%, respectively, after 48-hour exposure with 0.1 µg/mL of each nanoformulation. The Smart NPs show dose-dependent cytotoxicity on the C4-2 cells as shown in Fig2..

Conclusion: In conclusion, the layer-by-layer nanoparticle was successfully developed using a combination of nanoprecipitation method and sodium acetate, with surface-active and coating properties. This study shows that the smart layer-by-layer monocarboxylate transporter 4 inhibitor/docetaxel-loaded PLGA-based nanoparticle significantly reduces the prostate cancer cell viability. This new delivery system can be promising to potentiate the efficacy and reduce the current clinical vehicle-associated side effects of docetaxel for prostate cancer therapy. In the future, we will conduct biodistribution and determine the pharmacokinetics parameters of the optimized smart nanoformulations.

References: Ngo, AN.; Chatman, K. K.; Douglas, D.; Mosley-Kellum, K. M.; Wu, K.; Vadgama, J., Engineering of layer-by-layer acetate-coated paclitaxel loaded poly(lactide-co-glycolide) acid nanoparticles for prostate cancer therapy- in vitro. J Pharm Sci 2024, 113 (11), 3375-3383.

Acknowledgements: The research reported was supported by Florida A&M University start-up Award #101, program 11, the RCMI Grant 5U54MD007582 from the National Institute on Minority Health and Health Disparities.

Table.1 Formulation Variables

Fig.2 Particle Size Distribution by intensity of (B1) of blank PLGA nanoparticles, (SB1) smart blank PLGA layer-by-layer (LBL) nanoparticles, (F1) MCT4i loaded PLGA nanoparticles, (SF1) smart MCT4i loaded PLGA LBL nanoparticles, (F2) docetaxel (DXT) loaded PLGA nanoparticles, (SF2) smart DXT loaded PLGA LBL nanoparticles, (F3) MCT4i/DXT loaded PLGA nanoparticles, and (SF3) smart MCT4i/DXT loaded PLGA LBL nanoparticles.

Fig.2 Percent C4-2 cell viability ( % control) treated 48 h with the different formulations. (B1) of blank PLGA nanoparticles, (SB1) smart blank PLGA layer-by-layer (LBL) nanoparticles, (F1) MCT4i loaded PLGA nanoparticles, (SF1) smart MCT4i loaded PLGA LBL nanoparticles, (F2) docetaxel (DXT) loaded PLGA nanoparticles, (SF2) smart DXT loaded PLGA LBL nanoparticles, (F3) MCT4i/DXT loaded PLGA nanoparticles, and (SF3) smart MCT4i/DXT loaded PLGA LBL nanoparticles.