Introduction: Today, cancer is one of the most important causes of death in the world. Cancer is a disease in
which some cells in the body begin to divide and multiply without stopping and they penetrate the
surrounding tissues and begin to spread. In the normal state of the body, cells grow and divide to from
the cells the body needs, Then, when these cells get old or damaged, a new cell takes their place. When
cancer occurs, this process breaks down and a tumor is formed by dividing and multiplying cells without
stopping. Today's common treatment methods have problems, For example, in the treatment of cancer,
due to the limited access of drugs to the cancerous tissue, it may also damage healthy cells and cause
many losses and on the other hand, the appropriate does of medicine does not reach the cancer cell.
With the advancement of nanotechnology, this problem can be completely solved. By using
nanoparticles, it is possible to target and accurately deliver the drug only to the cancer tissue and cell,
which reduces the possible damage to the healthy cell to zero. With the invention of nanorobots, a
treatment of cancer. Nanorobots deliver drugs to cancer cells, by penetrating the cancer cell, they
destroy it! And by sensitizing the cancerous tissue, they cause accurate imaging of the tissue. Therefore,
nanotechnology creates a big revolution in cancer treatment.
Methods: This article is a review and field and library methods have been used
Results: Conclusions can be drawn from these studies. Cancer is a common disease that causes
death in the world, Although today's treatment methods slightly prevent cancer progression,
there is still no effective and useful method with the least damage. But nanotechnology has
provided useful methods and solutions with minimal damage. Because drug transfer in
therapeutic methods is not targeted, it may also damage healthy cells and tissues, and this
problem is solved with nanoparticles. Although they are very small, they penetrate into the
cancer cells and deliver drugs only to the cancer cells in a targeted way, which reduces the
damage of the treatment methods. Chemotherapy is one of the most widely used methods for
cancer treatment, but chemotherapy drugs are undesirable due to side effects and high toxicity
sine these drugs do not target the cancer cell, this problem can be solved in chemotherapy with
nanoparticles. Radiation therapy also has disadvantages, For example, exposing the body to
high-energy radiation causes problems that, if radiation therapy is combined with
nanotechnology, will have a significant impact on cancer treatment. Also, with the invention
of nanorobots, a huge revolution was created in cancer treatment. These nanorobots can be
easily used for drug delivery. It also examines the cancerous tissue and finally causes the
destruction of the cancerous tissue and destroys the cancerous cells, which greatly increases
the probability of survival of people with cancer. Today, scientists are focusing on various
methods based on nanotechnology to provide new and potential ways to treat cancer. In fact, it
can be said that the combination of nano science with cancer treatment methods can create a
miracle in the treatment and recovery of patients suffering from all types of cancer.
Conclusion: What is cancer?
Cancer is one of the common diseases that affects many people around the world. Cancer is
one of those diseases that starts in one part of the body and if it is diagnosed late, it spreads
throughout the body and affects all the important organs of the body. In fact, cancer is a disease
in which some cells in the body begin to divide without stopping and penetrate and spread to
the surrounding tissues (2). In the normal state of the body, the cells of the body grow and
divide to form new cells that the body needs. Then when the cells get old, they die and a new
cell takes their place. When cancer occurs, this process is broken and old or damaged cells
survive when they should be killed, then begin to divide and multiply and may lead to tumor
formation (3). Many cancers have solid tumors, but blood cancers like leukemias don't produce
solid tumors (6). Cancerous tumors are either malignant or benign, malignant tumors mean that
the cancer cells in the tumors tissue can invade the surrounding tissues and then spread and on
the other hand, the location of malignant tumors is sensitive and the surgery of this type of
tumor is very sensitive and risky, and even if the malignant tumor is surgically removed, there
is a possibility of its regrowth (3). While a benign tumor doesn't invade surrounding tissue, it
doesn't spread to nearby tissues, and if benign tumors are removed, they will not grow back,
and the surgical risk of benign tumors is often lower than that of malignant tumors (3).
How does cancer accur?
Cancer is genetic disorder, that is, it's caused by the change of genes in the cell
that control the function of the cells, especially the way they grow and divide (7). Genetic
changes that cause cancer may be inherited from parents. It's also possible that the
environmental factors that a person has encountered during her or his life can cause genetic
disorders and cause cancer. Environmental factors such as chemicals in tobacco and UV rays
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from the sun. For example, people who use drugs may increase their risk of cancer by several
percent (6).
When does cancer spread in the body?
If cancer starts from one place and spreads to other parts of the body, it's called metastatic
cancer, and the process that causes cancer to spread in the body is called metastasis (4).
Metastatic cancer cells look similar to primary cancer cells under the microscope and both have
some molecular features such as chromosomal changes. The overall goal of treating metastatic
cancer is to control the growth of the cancer or to relieve the symptoms caused by the cancer.
Metastatic tumors cause severe damage to the immune system. Therefore, most of the people
who die from cancer, metastatic cancer is the cause of their death (5).
How to diagnose cancer
Cancer diagnosis requires physical tests, if cancer is detected in time, it can be prevented
from spreading and affecting the important organs of the body (3). Some of the cancer
diagnosis methods include the following; 1- Laboratory tests , 2- Diagnosis imaging ,
3- Genetic tests , 4- Tumor sampling (4).
Cancer treatment methods
Cancer treatment depends on the type, location and extent of its spread in the body. Cancer
treatment methods aim to improve the patient's condition or prevent cancer progression.
According to the patient's condition, one or two methods are used in combination for
treatment. Methods include the following: 1- Surgery 2- Chemotherapy 3- Radiotherapy
4- Immunotherapy 5- Hormone therapy (9).
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Nanotechnology in cancer treatment
Chemotherapy is one of the well-known methods for treating cancer patients. But cancer
treatment has not been very successful due to the limited access of drugs to cancer tissue,
intolerable toxicity and multiple drug resistance. In recent years, due to the better understanding
of tumor biology and the advancement of nanotechnology, new solutions for cancer treatment
have been presented. Nanoscale particles act in surprising ways (10). So that the properties and
characteristics of materials change on a nanometer scale and they show special optical,
electronic and structural properties. It was the first nano cancer drug approved by the US Food
and Drug Administration. Since 1995, it has been used to treat adult cancers, including ovarian
cancer, multiple myeloma, and sarcoma { A rare cancer that often affects immunocompromised
patients such as AIDS patients.} is used (5). It's possible that common and classic cancer
treatment risk damaging healthy tissues. In fact, to destroy the cancer cells, the rest of the
healthy tissues are forcibly affected (3). Scientists are currently working on nanotechnologybased cancer treatment to overcome this limitation and increase the likelihood of healthy tissue
survival in several types of cancer (4).
How nanotechnology affects cancer treatment?
By delivering the drug to the specific target of cancer cells, nanotechnology improves current
treatment methods such as chemotherapy and reduces its adverse effects (10). Also, surgery to
remove tumors is done with much more precision. The effectiveness of radiotherapy and many
common treatment methods increases. Researchers are developing therapies with newly
discovered nanoparticles that have new properties for use in medical science. While
nanoparticles are very small in size, they contain small amounts of medicinal compounds (6).
As a result, things like combination drug delivery, multimodality therapy, and theranostic
performance {combination of therapy and diagnosis} become easy. The energy absorption and
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reradiation properties of nanoparticles also help them improve laser and hyperthermic
applications that disrupt diseased tissue (9).
Drug delivery with the help of nanoparticles
The main application of nanotechnology in oncology is drug delivery. A lot of research shows
that nanotechnology is successfully used to design many systems. These systems limit the side
effects of drugs and increase the patient's chances of health (2). They also allow chemotherapy
to be more selective, thus delivering drugs to specific tumor tissues. This methods involves the
development of nano sized carriers that deliver the drug to its target {Figure1}. In animal
studies, this system has been shown to be effective in delivering capecitabine to diseased cells
while bypassing healthy cells. This reduces side effects and increases the efficiency of the
tumor reduction activity (5).Strengtheningi mmunotherapy with nanoparticles
Another encouraging area of nanotechnology in oncology is the enhancement of
immunotherapy. While immunotherapy was previously recognized as an exciting and
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potentially very effective treatment option for the treatment of various types of cancer,
However, the proportion of patients who respond positively to immunotherapy is low, with
only 15% of patients showing an objective response rate across symptoms. This is related to
multiple methods of tumor immunity (11). To optimize the efficiency of the immune system
against cancer, nanotechnology is used to manage the spatial and temporal control of the
immune system(7).
Nanotechnology and immunotherapy
Immunotherapy is performed in about half of cancer patients during a treatment period.
In immunotherapy is effective in reducing the size of tumors by exposure to high energy rays.
However, these rays can also damage healthy cells(5). Scientists are working on increasing the
effect of radiationtherapy and developing new electromagnetic radiation. The combination of
nanotechnology and immunotherapy produces more effective results than immunotherapy
alone(10).
Nanorobot
Recent successes in targeted cancer therapy have led to the invention of nanorobot molecular
machines. Nanorobots have revolutionized the diagnosis and treatment of cancer. Nanorobots
are made of organic and intelligent materials that are programmed into units through genetic
embedding of their constituent structures (10). Most nanorobots consist of a sensing agent and
a cytotoxic agent. The sensor agent can consist of one or more chemical strands, each of which
is activated by a specific agent in the target cell. These nanorobots consist of a gold nanoshell,
an antibody fragment, and an aptamer sensing agent. An agent is a molecular sensor that
recognizes antigens on the surface of certain cancer cells (9). After identifying the cancer cells,
its contents are dissolved and the loaded substances penetrate into the cancer cells and destroy
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the cancer cells. Recently, nanorobots have been designed as an intelligent drug delivery
system (10). When the nanorobot is in close proximity to cancer cells, it triggers the release of
thrombin, which causes blood to clot at the tumor site and finally, it causes tumor necrosis and
inhibits the growth of cancer cells(9).New solutions for the treatment of cancer stem cell
In the current treatment of cancer, the issue of drug resistance leads to the
accumulation of cancer stem cells and the recurrence of treated tumors. Various solutions
have been proposed for the treatment of cancer, the most important of which is the use of
drug delivery systems based on nanoparticles (2). These solutions can be divided into three
main categories: 1-Targeted drug delivery to cancer stem cells (using different nanocarriers
such as liposomes, micelles, nanotubes, nanogels)
2-Targeting resistance genes.
3-Destruction of the nest of cancer stem cells (2).