الفهرس 
Title pageOnly 14 pages are availabe for public view
 |  | from | 97 |  |  |
| | | from | 97 | | |
Abstract
Breast cancer is the most common cancer in women. It is a heterogeneous disorder,
in this way the helpful choices assurance is one of the significant difficulties for BC
treatment. There are two principle type of treatments conventional monotherapy and
combined therapy. One of the most exceptional and most recent joined treatment is the
utilization of gold nanoparticles (GNPs) with another treatment technique.
MCF-7 cells is one of the most generally utilized exploratory models for in vitro
considers of breast carcinoma detailed just because that AuNPs displayed portion
subordinate cytotoxicity and improved apoptosis of MCF-7 cells by downregulation of bcl-
2 and upregulation of p53, bax, caspase-3 and caspase-9.
The main goal of the present work is investigate the productivity of radiotherapy and
photothermal monotherapies in comparison to gold nanorods in MCF-7 breast cancer cell
model.
This trials includes six groups; each considered group was presented to an alternate
treatment with the exception of the control group. The treatments included with GNPs,
radiotherapy, laser, photothermal, and radiosensitization. The viability is evaluated
utilizing MTT to decide the viability as a treatment sway pointer. After treatment (at the
planned times), cells were gathered, and pellets were put away at - 80oC for assurance of
quality articulation of apoptotic markers (Bim and Noxa).
In the present study, the toxic response of AuNPs mixture (spheres and NRs;
(p<0.001) on MCF-7 showed a dose dependent response after 4- and 48-hours incubations.
This toxicity was accompanied by a change in the expression of Bim and Noxa proapoptotic
genes. Both Au-nanospheres- and AuNRs- mediated PTT showed significant
reduction (p < 0.001) in cellular viability of MCF-7. It is evident that AuNPs promote
thermal killing. Laser radiations collide AuNPs causing electron excitation which reach to
new equilibrium Fermi electron distribution via energy redistribution. Hot electrons
transfer their heat and energy to the lattice (10° Kelvin), in picoseconds, through phononphonon
scattering and AuNPs are rapidly getting cold.
Radio sensitization by AuNPs was thought to stem from physical dose enhancement
by Au. However, experimental data showed their contribution in all the three phases .The
current results showed DEF of more than 12 for AuNPs mixture (0.05 g/ml, 4 hours
incubation prior to x-ray irradiation) indicating a potential radiosensitizing effect at both
zero- and two-days post-irradiation of MCF-7 cells. Although a pronounced radiosensitization
was observed at both zero- and two-days post x-ray irradiation at 0.5, 1.0, 2.0,
and 2.5 (Gy), this effect was independent on Bim and Noxa gene expression except for
Noxa upregulation two-days post x-rays irradiation. This would implicate contribution of
other biological mechanisms other than apoptosis.