Treatment of tumour tissue with radio-frequency hyperthermia (using antibody-carrying nanoparticles)

Abstract

Intelligent inorganic nanoparticles were designed and produced for use in imaging and annihilating tumour cells by radio-frequency (RF) hyperthermia. Nanoparticles synthesised to provide RF hyperthermia must have magnetite properties. For this purpose, magnetite nanoparticles were first synthesised by the coprecipitation method (10-15 NM). These superparamagnetic nanoparticles were then covered with gold ions without losing their magnetic properties. In this step, gold ions are reduced around the magnetite nanoparticles. Surface modification of the gold-coated magnetic nanoparticles was performed in the next step. A self-assembled monolayer was created using cysteamine (2-aminoethanethiol) molecules, which have two different end groups (SH and NH₂ ). These molecules react with the gold surface by SH groups. The NH₂ groups give a positive charge to the nanoparticles. After that, a monoclonal antibody (Monoclonal Anti-N-CAM Clone NCAM-OB11) was immobilised by the 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide/N-hydroxysuccinimide method. Then, the antenna RF system (144.00015 MHz) was created for RF hyperthermia. The antibody-nanoparticle binding rate and cytotoxicity tests were followed by in vitro and in vivo experiments. As the main result, antibody-bound gold-coated magnetic nanoparticles were successfully connected to tumour cells. After RF hyperthermia, the tumour size decreased owing to apoptosis and necrosis of tumour cells.

FIGURE 1

Fourier transform infrared of synthesised nanoparticles

FIGURE 2

Vibrating sample magnetometer curve of magnetic and gold‐coated magnetic nanoparticles

FIGURE 3

X‐ray diffraction pattern for magnetic nanoparticles and gold‐coated magnetic nanoparticles

FIGURE 4

X‐ray photoelectron spectroscopy spectra of Au @ SPIONs nanoparticles. (a) Fe (2p), (b) O (1s), and (c) Au (4f). Au @ SPIONs, gold‐coated superparamagnetic iron oxide nanoparticles

FIGURE 5

Transmission electron microscopy of magnetic nanoparticle

FIGURE 6

Transmission electron microscopy of gold‐coated magnetic nanoparticles

FIGURE 7

Antibody‐nanoparticle binding rate

FIGURE 8

Effects of nanoparticle concentration on cell viability to determine toxicity limit

FIGURE 9

Difference in heat production in nanoparticles dispersion owing to radio‐frequency exposure

FIGURE 10

MCF‐7 cells were analysed by DAPI (4′,6‐diamidino‐2‐phenylindole) filtration (a). The interaction of Au @ SPIONs (20 μg/ml) with MCF‐7 cells was analysed by DAPI filtration (b). The interaction of antibody‐bound Au @ SPIONs (20 μg/ml) with MCF‐7 cell before radio‐frequency (RF) was analysed by DAPI filtration (c). The interaction of antibody‐bound Au @ SPIONs (20 μg/ml) with MCF‐7 cell after RF was analysed by DAPI filtration (d). Au @ SPIONs, gold‐coated superparamagnetic iron oxide nanoparticles

FIGURE 10

MCF‐7 cells were analysed by fluorescein isothiocyanate (FITC) (480–520 nm wavelength) (a). The interaction of Au @ SPIONs (20 μg/ml) with MCF‐7 cells was analysed by FITC (b). The interaction of antibody‐bound Au @ SPIONs (20 μg/ml) with MCF‐7 cell before radio‐frequency (RF) was analysed by FITC (c). The interaction of antibody‐bound Au @ SPIONs (20 μg/ml) with MCF‐7 cell after RF was analysed by FITC (d). Au @ SPIONs, gold‐coated superparamagnetic iron oxide nanoparticles

FIGURE 11

Results from cell culture experiments

FIGURE 12

Magnetic resonance imaging of intravenous injection after (a) 0 h, (b) 2 h, (c) 4 h, and (d) 24 h

FIGURE 13

Magnetic resonance imaging of intravenous injection after (a) 0 h, (b) 2 h, (c) 4 h, and (d) 24 h

FIGURE 14

Magnetic resonance imaging after radio‐frequency application in intravenous injection group after (a) 1 week; (b) 2 weeks; (c) 3 weeks

FIGURE 15

Magnetic resonance imaging after radio‐frequency application in intratumour injection group after (a) 1 week; (b) 2 weeks; (c) 3 weeks

FIGURE 16

Data of intravenous injection group after radio‐frequency application

FIGURE 17

Data of intratumour injection group after radio‐frequency (RF) hyperthermia

FIGURE 18

Local photo from mouse: (a) immediately after radio‐frequency (RF) application; (b) 1 week and (c) 3 weeks after RF application in intratumour injection group

FIGURE 19

Local photo from mouse: (a) immediately after nanoparticle injection; (b) 1 week and (c) 3 weeks after nanoparticle injection in control group

FIGURE 20

(a) immediately after radio‐frequency (RF) application; (b) 1 week and (c) 3 weeks after RF application in intravenous injection group

FIGURE 21

(a) control group immediately after nanoparticle injection; and (b) 3 weeks after nanoparticle injection

FIGURE 22

Histopathology evaluation of control group (a) → desmoplasia, ○ tumour cells, □ malignant tumour cells, □ macrophage cells; (b) ○ mitosis (mitotic division)

FIGURE 23

Histopathological microscopic images of tumours after radio‐frequency hyperthermia treatment: (a, b) intratumour group; (c, d) intravenous group). ○, tumour Cells; □, histiocytes; →, fibrotic tissues