The potential application of using nanoparticle to label glioblastoma in vitro

Abstract

Astrocyte is one kind of star-shaped neuroglial cell in the brain Their main functions are maintaining the healthy central nervous system (CNS)[1] forming the structure blood-brain-barrier with pericytes and vessel endothelial cells to protect the brain Glioblastoma (GBM) is a disease due to abnormal cell division of astrocytes There are necrotic tissue and massive vascular proliferation inside the tumor Because the infiltrating property removal of the whole cancer cells is difficult in surgery The patients’ survival rate is low From the literature search the epidermal growth factor receptor (EGFR) is amplified at the cell membrane of GBM and the blood-brain-barrier (BBB) next to tumor has been collapse by the pressure from tumor In this study I used these properties including massive vascular proliferation in the tumor and used the functional gold nanoparticles (Core-satellite assemblies CSA) conjugated with anti-EGFR antibody to target tumor cells In the beginning of the experiment I used immunocytochemistry and Western blot to confirm rat GBM cells (CNS-1) that expressed EGFR Next I tried to confirm the specificity of CSAG1@SiO2@anti-EGFR by modified ELISA Bradford assay and SEM but the results couldn’t totally confirm the specificity of CSAG1@SiO2@anti-EGFR due to the unstable structure of CSAG1 Therefore CSAG2 were developed To further confirm the specificity the CSAG2@anti-EGFR and CSAG2@IgG were used to test The results showed that the suitable condition was after reacted with 1 8×109 CSAG2@anti-EGFR for 3hours then 410W/cm2 of 660nm laser irradiated for 3minutes 5points or 1minute 7points After confirming the specificity of CSAG2@anti-EGFR I used a co-culture system that seeded CNS-1 and rat astrocytes in the same well to imitate tumor margin in vivo The results showed that cells reacting with 2 5×109 CSAG2@anti-EGFR for 3hours and irradiated 410W/cm2 of 660nm laser for 3minutes 5points and 1minute 7points would increase the cell death rate suggesting that the CSAG2@anti-EGFR have potential in targeting tumor cells To distinguish tumor cells from normal cells by human eyes is difficult Therefore the doctors or scientists developed tools Raman scattering is a phenomenon of inelastic scattering Due to the weakness of signal this technique wasn’t used widely in the past few decades until surface-enhanced Raman scattering (SERS) was discovered Gold nanoparticle is one of the materials that have been widely used in SERS via the surface plasma resonance The main advantage of SERS is stable signal in water Human body contains 70% of water suggesting SERS signal might be applied to human The Cy5-CSAG3@anti-EGFR was developed to enhance Raman signal and could be applied not only to track GBM cells but also other cancer cells with metastasis In this study I used the co-culture system to confirm the effect of Raman guided photothermal therapy and to test the potential of Cy5-CSAG3@anti-EGFR in future clinical application

Date of Award	2019
Original language	English
Supervisor	Chun-I Sze (Supervisor)