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J Pharmacol Ther Res 2017 Volume 1 Issue 2
November 02-03, 2017 Chicago, USA
4
th
International Congress on
International Conference and Exhibition on
Drug Discovery, Designing and Development
Biochemistry, Molecular Biology: R&D
&
Nanomaterial regulates the radiosensitivity in colorectal cancer cells
Shengfang Ge
Shanghai JiaoTong University School of Medicine, China
Introduction:
Colorectal cancer (CRC) is a common
gastrointestinalmalignant tumorwithhigh rateof postoperative
recurrence. And the risk of metastasis of CRC is still one of
the main reasons for the failure of CRC treatments. Radiation
therapy is a commonly method to treat CRC, which occupies an
irreplaceable important position in surgery, chemotherapy and
other treatments. Metal-based nanomaterial was deemed as
one of the radio sensitivity agent due to atom effect.
Objective:
To improve the effects of irradiation on tumor cells,
we testified the effect of Graphene Quantum Dots (GQDs)
with good biocompatibility and rich oxygen groups on radio
sensitivity. Meanwhile, we investigated the radio sensitivity
mechanism of GQDs. Our study would provide reliable
experimental basis for GQDs as a radiotherapy sensitization
agent in potential clinical applications.
Contents &Methods:
The GQDs were prepared with graphene
oxide (GO) andthesafeconcentrationofGQDsweredetermined
by CCK8 assay, laser confocal microscope and transmission
electronmicroscopy are carried out tomeasure the sub-cellular
localization of GQDs, the proliferation ability of different treated
groups were detected by performing CCK8 assay and colony
formation assay, the cell apoptosis rate and the cell cycle arrest
of treated groups were detected by Flow Cytometry, the cell
damage was observed by transmission electron microscopy,
the production of ROS andmitochondrial ROS in treated groups
were measured by DCFH-DA and MITOSOX Red Indicator,
respectively, the expression of γH2AX which reflect the degree
of DNA double-strand breaks was detected by western blot
after different treatments.
Results:
The safety concentration of GQDs on SW620 and
HCT116 cells was 50 μg/mL. Transmission electron microscopy
and laser confocal microscope revealed that GQDs were mainly
distributed in cytoplasmof cells. In addition, our study indicated
that GQDs could decrease the cell viability, increase the degree
of cell damage and cell apoptosis of SW620 and HCT116 cells
under the irradiation synergistic effects. Meanwhile, with the
synergistic effects of ionizing radiation, GQDs could enhance
intracellular ROS generation of SW620 and HCT116, and
increased the ROS levels in mitochondria which increase DNA
double-strand break out and G2/M phase cell cycle arrest cells.
Conclusions:
This study demonstrated that GQDs have good
radio sensitivity at cell levels
in vitro
, which can improve the
killing effects of irradiation on tumor cells, and ultimately
achieving treating cancer. It illustrates that GQDs present great
potentials in tumor therapy as a new type of radio sensitivity
agent. In this seminar, I will discuss the protocol we developed
to pattern the first human hNT neurons on parylene-C/
SiO2 substrates and how, in our more recent work, we have
patterned the first hNT astrocyte, on such substrates to single
cell resolution.
e:
geshengfang@sjtu.edu.cn