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Nanotechnology in Cancer Treatment
Kenneth Milne
Introduction to Nanotechnology
Dr. James Smith
2 December 2013
Nanotechnology is influencing our understanding of cancer and how we are able to fight it.
Action towards better cancer prevention, affective diagnosis of the illness, and more enhanced
ways to treat and fight it are 3 ways in which nanotechnology is being applied to cancer.
Nanotechnology could be the answer to weaken the threat of cancer, allow us to recognize it
earlier, and abate its symptoms. Many cancer treatments are ineffective and there is high
difficulty in early cancer detection. Cancer nanotechnology research incorporates biology,
engineering, chemistry, physics and medicine. It is being used more and more in almost all
fields of work.
One example in which nanotechnology is being used to prevent cancer is in fighting skin
cancer or melanoma. Nanotechnology can be applied to sunscreen. Sunscreen generally rubs
off easily and has to be reapplied periodically. There can also be many openings left in the
sunscreen, exposing the skin. Nanoparticles are extremely more effective in absorbing light,
especially ultra-violet light. Nanoparticles are smaller so it spreads easier, covers your body
better and it is cheaper since you use less. Nanoparticles could possibly be manufactured
attached to UV substances and then targeted to skin cell surface proteins. They can then be
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properly coated by sunscreen on a nanoscale. This will allow the body to be better protected
from UV rays.
There is a high difficulty in early cancer detection. This results in patients having to suffer
more than if the cancer was discovered earlier on. High nanosensor devices can be used to
detect biological signs of cancers. Nanoparticles can be used to detect or monitor cancer cells
by using magnetic and fluorescent properties.
Other therapeutic and diagnostic uses of nanotechnology has great potential. Linda Molnar,
of the NCI Alliance, says there is a future where new imaging agents, new diagnostic chips and
new targeted therapies can come together to create a new form of personalized medicine. This
will provide early and more accurate detection which will lead to quicker initiation of treatment
and diagnostic tests to see whether the patient is responding. She says, "The sooner you can
detect the cancer and start treatment, and know that you're treating that patient with a
therapy that they respond to, the better," says Molnar. Because of this, people are very excited
and recently, a lot more money has been invested into nanotechnology for cancer. This includes
the possibility of using nano-sized imaging agents that can find tumors and cancer cells in order
to better observe growth as it goes through therapy. They can be conjugated with biomolecular
targeting ligands and used to target these tumors
Gold nanoparticles can also be effective in detecting cancer cells. These particles can affiliate
much better with cancer cells and absorb light. With some white light and a simple, microscope
is all that’s necessary to see the gold nanoparticles and detect the cancer. Gold-coated
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nanoparticles are conjugated to recognize molecules. The basic principle is that these particles
absorb laser radiation and convert it to heat. To reach the desired goal, you use gold
nanoparticles and conjugate them to recognition molecules to target cancer cells. Gold
nanoshells can be linked to antibodies that recognize tumor cells. Once they are linked nearinfared light is applied and kills only the tumor and leaves healthy cells alive. Once the light is
applied the tumor cells are heated are thermally destroyed with minimum damage to healthy
cells. To summarize, light responsive nanoparticles are very useful tools for cancer treatment
and land can be specifically targeted at specific cell types by using the right recognition
molecules.
Unfortunately, in chemotherapy, cancerous cells can be destroyed but it also kills the
healthy cells, which is why many lose their hair and weight and have many other problems.
Cancer cells are unique and can be disrupted by nanoparticles. Cancer cells are able to take in a
large amount of nutrients due to its rapid growth. Nanoparticles could be used to carry certain
agents to cancer cells and tumors, such as Paclitaxel. Nanovectors, or nanoparticles can be
developed and loaded with drugs or imaging agents and then targeted to tumors. They are able
to coat nanoparticles with aptamers, which are used to aid in targeting the tumor and guide
them towards it. They are than able to bind and enter the cells and then dissolve in order to
spill out their contents, which could be an anticancer drug such as docetaxel. The nanoparticles
are also coated with polyethylene glycol (PEG) to help them safely pass through the
bloodstream and eventually into the tumor cells. This method has been tested on mice with
prostate cancer. They used a single injection of the nanoparticles coated with these aptamers
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to bind to prostate cancer cells. This resulted in a great success. The nanoparticles actually
attached to the cancer cells.
After more research, I found out that Angiogenic blood vessels supply tumors with
nutrients, but fortunately because of their rapid growth, they are unbalanced have larger gaps
in their walls than healthy blood vessels. The gap sizes generally range from a few hundred
nanometers to a few microns. On the other hand, the pores in normal blood vessels are just 26 nm in size. Nanoparticles between 10 and 300 nm in diameter are the perfect size to pass
through the gaps in the blood vessels that supply the tumors but they don't affect the healthy
tissue. By loading the particles with chemotherapy drugs or cancer killers you can deliver the
drugs to tumor cells without damaging healthy cells. These antiangiogenic medicines also lower
the pressure at the center of the tumor to control the delivery of the drug. Nanoparticles can
be designed to release their drug loads in response to an outside stimulus such as light,
ultrasound, heat, or a magnetic field. Once the drug is released, it is no longer inside the
nanoparticle and can spread more easily through the tumor. It is said that these technologies
are working and many cancer patients are benefiting.
In one experiment 7 mice were tested over the course of 109 days. 5 of them had tumor
reduction and 2 of them had complete tumor reduction, but there was 57% survivability. Yet
this report shows the potential of using nanoparticle-aptamers in treating certain types of
cancer cells and reducing tumors. The mice that were treated with the targeted nanoparticles
survived and had a much lower level of toxicity.
So targeted therapies can be used to avoid killing the healthy cells and to avoid the toxic side
effects that results from chemotherapy. The more nanoparticles that are sent into the body
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results in the greater amount of nanoparticles those get into the cancer cells. One study
performed consisted of 3 humans with skin cancer. One human was injected with nanoparticles
into the bloodstream in order to target the proteins related to cancer progression. Those
proteins were shown to have reduced. The nanoparticles got inside all the tumor cells of all
three patients.
Also the use of near-infrared light was proven to be very effective in mice. A single
nanoparticle injection was able to destroy tumors in the mice when they were expsed to nearinfrared light. The cancer cells were able to be heated and killed. Cancer cells can only survive
at a certain temperature, despite other cells. In this way, it is hoped to be able to just kill the
cancer cells and avoid killing the wanted cells.
It is difficult to create nanoparticles that will target the correct tissues and cells.
Nanoparticles can be used to target bio-markers or antigens that are specific to cancer cells.
Another option is to use the nanoparticles’ physical characteristics such as size, shape, density
and physical properties to guide them through the body and cross the biological membranes.
Joseph DeSimone, a professor of chemistry and chemical engineering at the University of North
Carolina is using this method. He said "We basically make moulds out of a really low-surfaceenergy fluoropolymer that allows us to synthesize truly engineered particles with desired
characteristics (Jones)." DeSimone's practice allows the accurate control over the particles,
such as their size, shape, and cargo. Using nanoparticles also allows them to measure the
amount of cargo they load in them.
In conclusion, nanotechnology has proven to be a great benefit in cancer research. It has
high hopes and is only rapidly growing. Nanoparticles can be used to improve sunscreen and
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make it more able to protect skin against UV rays. Cancer can be discovered and observed more
effectively earlier on through the use of imaging agents and gold nanoparticles. The gold
nanoparticles can find the cancer cells and when exposed to light it reveals the cancer sites. The
new targeting therapies are also very interesting. Nanoparticles can be guided through the
body to find the cancer sites and deposit anticancer chemicals. They can be molded in order to
better flow through the blood stream and reach cancer sites. Cancer cells can also be heated up
when exposed to infrared light and destroyed, without destroying the healthy cells. This is all a
result to the new use of nanoparticles being used to find cancer sites and destroy them.
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Works Cited Page
Acosta, Richard, “Nanotechnology in Cancer Treatment and Detection,” Paul Hansma
Research Group, Hansmalab website, 18 August 2010, web/pdf, 20 November 2013
Grossman, J. H., & McNeil, S. E. (2012). “NANOTECHNOLOGY IN CANCER MEDICINE”.
Physics Today, 65(8), 38-42. August 2012, Web, 26 November 2013
Jones, Dan, “Cancer Technology, Small but Heading For the Big Time,” Nature Publishing
Group, Nature Website, March 2007, Web, 20 November 2013
Landau, Elizabeth, “Nanotech Cancer Treatment Shown to Work in Humans,” CNN, CNN
website, 22 March 2010, 16 November 2013
Mansoori, Ali; Mohazzabi, Pirooz; McCormick, Percival; Siavash, Jabari, “Nanotechnology in
Cancer Prevention, Detection and Treatment: Bright Future Lies Ahead,” Inderscience
Enterprises Ltd., World Review of Science, Technology and Sustainable Development,
November 2007, Web, 18 November 2013
Misra, R., Acharya, S., & Sahoo, S. K. (2010). “Cancer nanotechnology: application of
nanotechnology in cancer therapy.” Drug Discovery Today, 15(19/20), 842-850.
doi:10.1016/j.drudis.2010.08.006, 24 November 2013.
Nanotechnology Now, “Current Nanotechnology Applications,” 7th Wave, Inc.,
Nanotechnology Now, 22 May 2012, Web, 18 November 2013
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Singer, E., Linehan, J., Babilonia, G., Imam, S., Smith, D., Loera, S., & ... Smith, Stromal
Response to Prostate Cancer: Nanotechnology-Based Detection of Thioredoxin-Interacting
Protein Partners Distinguishes Prostate Cancer Associated Stroma from That of Benign Prostatic
Hyperplasia. Plos ONE, 8(6), 1-6. doi:10.1371/journal.pone.0060562, 18 November 2013
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