Synthesize of Chitosan Nanoparticles Contained BRD4 Inhibitor and Its Effects On Breast Cancer Cell Line In In Vitro

• Main Author: Prameswari Hanifa (NIM : 10613064), Yukiko
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/31810
• Institution: Institut Teknologi Bandung

<p align="justify">Cancer is one of the most dangerous diseases in the world and contributes to 55% of the burden of diseases in developing countries. One of the most common cancer found among Indonesian woman is breast cancer with the third highest number of deaths in Asia. Breast cancer is caused by abnormal cell growth due to genetic disorder and epigenetic alteration. One of the protein groups that involves in recognition of cancer epigenetic marker is bromodomain extra-terminal (BET), such as BRD4, which functions in regulating gene expression. BRD4 also has an important role in controlling cell cycle, proliferation, migration and invasion of breast cancer cell. Therefore, BRD4 is used as a therapeutic target of breast cancer using BET inhibitor, I-BET762. To ensure that I-BET762 is perfectly delivered to target cells, a safer and more effective drug delivery system with chitosan nanoparticle is required. The aim of this study is to synthetize and characterize the drug delivery system of chitosan nanoparticles and to analyze its effect by determining IC50 value of chitosan nanoparticles that contain I-BET762 as BRD4 inhibitor (I-BET762 nanoparticles) on MCF7 breast cancer cell line in in vitro system. Ionic gelation method was used to synthetize chitosan nanoparticles with formulation of 0,075% chitosan and 0,025% TPP which were obtained from a previous study. Nanoparticles size, polydispersity index (PDI) and zeta potential were determined using Particle Size Analyzer (PSA) Malvern Zetasizer Nano ZS. Transmission electron microscopy (TEM) was used to analyze the morphology of nanoparticles. Lyophilization of nanoparticles suspension was performed with the addition of 10% Trehalose as cryoprotectant. The cytotoxicity test of nanoparticles I-BET762 was performed by MTT assay on MCF-7 cancer cell line cultured on 96-well plate and treated with a series of concentrations of I-BET762 nanoparticles from 4 nM to 128 nM. The MTT assay that was used to determine the IC50 value of I-BET762 nanoparticles and was observed after 48 hours of treatment. The IC50 value was quantified with statistical software GraphPad Prism 7. The measurement result using PSA showed the mean diameter of I-BET762 nanoparticles was 210.5 nm, PDI value was 0.261, and the value of zeta potential was +28.8 mV. The TEM observation showed that the morphology of I-BEET762 nanoparticles were spherical. Based on the MTT assay results, IC50 value of I-BET762 nanoparticles that was calculated from GraphPad Prism 7 software was 49.47 nM. The IC50 value of the I-BET762 nanoparticles was lower than I-BET762 without encapsulated nanoparticles (76.87 nM). These results suggested that the I-BET762 which were encapsulated in chitosan nanoparticles have a higher cytotoxicity effect than free I-BET762 because nanoparticles can deliver the I-BET762 more effective than free I-BET762. The size and the surface charges of the nanoparticles increase the selectivity, absorption, and cellular cytotoxicity of I-BET762. In summary, I-BET762 nanoparticles was succesfully synthetized with mean diameter was 210.5 nm, PDI value was 0.261, zeta potential was +28.8 mV with spherical morphology. The IC50 value of I-BET762 nanoparticles and I-BET762 that was calculated from GraphPad Prism 7 software was 49.47 nM and 76.87 nM respectively.<p align="justify">