3.2. Analysis of the anti-oral cancer properties of AgNPs
The anti-cancer properties of nanoparticles have been known for several
years, and for this reason, nanoparticles are of great importance.
Because several genetic changes are needed to create a cancerous form of
a cell and because the development of many cancers is hereditary, in
some types of cancer, after treatment and surgery, it is possible to
create a primary mass [48-51]. Apoptosis, in addition to metastasis,
is the most important form of cell suicide. In this process, dangerous,
damaged, and unwanted cells are removed without damaging the surrounding
tissues or cells. Cancer cells escape from programmed death, one of the
reasons for which is the convert in the gene expression that is involved
in the process regulation. Most anticancer agents exert their remedial
activities by inducing apoptosis [52-55]. Programmed death induction
is a main important method to kill tumor cells without complications. In
recent research, by the MTT colorimetric method, it was indicated that
nanoparticles have a concentration-dependent lethal activity on tumor
cells. In addition, it was found that nanoparticles increased apoptosis
in cancer cells. Today, the focus of cancer studies is the search for
anti-cancer agents with a higher safety factor and greater acceptability
for patients. In addition, nanoparticles can act synergistically or
redundantly in combination with radiation therapy or chemotherapy for
anticancer activity [56-59]. With the advent of nanotechnology, the
paradigm of drug delivery systems has been developed, which can carry
many drugs with chemical properties and actively target specific cells.
Also, it can pass through biological barriers and transfer its cargo to
the target location without pharmaceutical interventions. Today, the
development of nanoparticles as effective drug carriers is at the center
of attention. In these effective carriers, the drug is at the center of
attention [58-60]. In this study, nanoparticles were used for
cytotoxic purposes by the MTT method. One of the reasons that
nanoparticles had a significant effect on cancer cells is that this
phenomenon is due to their direct effect on the cell’s respiratory
system in the mitochondria. Therefore, due to the high level of
mitochondrial activity in the respiration process of cancer cells
compared to normal cells, a suitable substrate is provided for
nanoparticles to destroy cancer cells. Another reason is the
morphological differences between the membranes of cancer cells in terms
of the size of their pores [61-63]. Various researches have been
conducted to investigate the cytotoxic activities of nanoparticles on
cancer cell lines [58-60]. The results of this study showed that
metal nanoparticles in low concentrations do not have significant
cytotoxic effects, but in higher concentrations, they have significant
cytotoxic effects. The results of this research showed that the
cytotoxicity of nanoparticles is dependent on dose and time and
suggested that this nanoparticle can have biomedical applications. In
general, the results of our study are consistent with other studies in
the field of cytotoxicity of nanoparticles. Another mechanism of
cytotoxicity of nanoparticles is the toxic oxygen radical’s generation
[58-61]. Another mechanism of nanoparticles cytotoxicity is the
toxic oxygen radicals (ROS) generation that disturb the cellular redox
balance, which is called oxidative stress. Oxidative stress destroys
cellular antioxidant enzymes, destruction of cellular DNA structure,
oxidation of cellular proteins and membrane lipids, and finally cell
death. One of the important issues in the field of using metal
nanoparticles in cancer treatment is the non-toxicity of nanoparticles
on normal cells [59-64]. Studies show that nanoparticles have a
greater effect on cancer cell lines, which is due to their direct effect
on the cell’s respiratory system in the mitochondria. Therefore, due to
the high level of mitochondrial activity in the respiration process of
cancer cells compared to normal cells, a suitable platform is provided
for nanoparticles to destroy cancer cells [64-67]. Another reason is
the morphological differences between the membrane of normal and cancer
cells in terms of the difference in the size of their pores. Also, the
difference in the shape, size and surface charge of nanoparticles is
another factor in the difference in toxicity of nanoparticles between
cancer and normal cells [67-69]. It is important to identify the
importance of the apoptotic genes expression pattern in response to the
anticancer drugs metastasis activity. Therefore, more investigations are
necessary to prove that the mRNA expression profile of this gene can be
in response to treatment [66-69]. The results obtained from this
study showed the therapeutic use of nanoparticles in cancer cells.
According to these reviews, clinical studies on human and animal models
are necessary to prove the effect of nanoparticles and also the effect
of these nanoparticles on healthy and normal cell lines. So, the
nanoparticle’s use can be efficient in enhancing the expression of some
proliferative and apoptotic genes [62-66]. According to this study
and previous research, it can be concluded that nanoparticles have
powerful anticancer effects on cancer cells and derivatives of this
compound can be used in the treatment of cancer. Therefore, if the
clinical process of this nanoparticle is confirmed, these nanoparticles
can be used in clinical cases for cancer patients in the future.
In this investigation, the treated cells with different concentrations
of the present AgNPs were assessed by MTT assay for 48h about the
cytotoxicity properties on normal (HUVEC) and oral malignancy cell lines
i.e. HSC-2, HSC-3, HSC-4, KB, BHY, HN, OECM-1, and Ca9-22 (Table
1;Figures 7-11).
In the recent study, the absorbance rate was evaluated at 570 nm, which
represented viability on normal cell line (HUVEC) even up to
1000μg/mL for AgNPs (Table 1 and
Figure 7).