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MICRORNAS: THE FUTURE OF CANCER TREATMENT
Megha Murthy, [email protected], Mahboobin 10:00, Shivani Tuli, [email protected], Budny 10:00
Abstract — Breast cancer affects millions of women each
year and researchers and scientists are still looking for a way
to detect it. Currently, various types of medical imaging
techniques, such as magnetic resonance imaging (MRI) and
positron emission tomography (PET) scanning, are used to
detect tumors in the body. However, these imaging modalities
cannot detect tumors until they are too large and malignant to
cure.
To improve clinical outcomes, it would be beneficial to
find a method for early detection of cancer at the cellular level
and target the disease before it develops further. Efficiency
and cost-effectiveness in detection and treatment can be
improved by conducting experiments and research at the
cellular level, for example on blood samples.
MicroRNAs, fragments of gene carriers that inhibit the
translation of RNA to protein, can help medical professionals
detect breast cancer, enabling doctors to often prevent further
cancer growth. Extracting blood and screening it for high
microRNA levels is a good indicator of existing cancer. By
detecting cancer before it develops into malignant tumors,
doctors will have more time to determine a treatment that
works best for the patient. This technology would enable
bioengineers and researchers to find a better treatment for
cancer.
The important factor to consider when dealing with
cancer treatment and detection is sustainability of the
technology. Sustainability involves providing health benefits
and improving the quality of life of the environment. Using
microRNAs will benefit both life and public health.
Combining microRNA technology with other treatment
methods, such as drug therapy, will make cancer therapy
more accessible. Detecting cancer early will also give more
hope to patients who may think there is no hope for a cure. It
will give medical professionals more time to find the most
appropriate treatment for everyone. MicroRNAs are the
future to detecting and treating cancer.
Every day, thousands of hospitals flood with patients
who seek treatment for breast cancer, the most common type
of cancer in women. Doctors, scientists, and engineers
continue to scramble to find an efficient, inexpensive
treatment for breast cancer. Understanding what breast cancer
is and how it spreads throughout the body will enable
researchers to find a better treatment than conventional
approaches.
Breast Cancer Pathogenesis
Cancer is a genetic disease caused by alterations of gene
expressions. Gene alterations occur during DNA replication.
In some cases, there will be a mistake during DNA replication
where one base is incorrectly paired up with another base (an
adenine (A) is paired with a cytosine (C)). Although there are
enzymes whose job is to fix these errors, the incorrect pairs
are sometimes incorporated into the DNA strand. Once this
occurs, the mistake is continued during DNA transcription
and mRNA translation. These mutations may give rise to
cancerous cells, which will then continue to spread
throughout the body as shown in the figure below.
Key Words—Breast Cancer, Cancer Detection, Cancer
Research, Gene Therapy, Genetic Engineering, microRNA,
Tumor Suppressors
HISTORY OF BREAST CANCER
TREATMENT AND MICRORNAS
University of Pittsburgh Swanson School of Engineering 1
3.31.2017
FIGURE 1 [1]
Cancer Arising from Mutated DNA
Megha Murthy
Shivani Tuli
Parts of the DNA strand are affected in a cancerous cell.
When paired with the wrong base, there is a higher chance
that mutations within the genes will arise. This means that
there is a greater chance an individual will have cancerous
cells running through their body.
Breast cancer, like other cancers, occurs when the cells
bypass the cellular checkpoints during normal cell division.
Unlike healthy cells, cancer cells ignore cues for apoptosis,
programmed cell death, and modify their molecular pathways
such that they keep dividing, eventually losing control, and
sometimes metastasizing to the rest of the body [2].
Predictions about where the cancer spreads will enable
doctors to find a treatment before the cancer cells have time
to transform from benign tumors to malignant tumors.
Cancerous cells can spread through the body in two ways:
through the blood vessels or the lymph system. Scientists
recently discovered that cancer cells enter blood vessels at a
specific site, the tumor microenvironment of metastasis
(TMEM), where endothelial cells (cells that line blood
vessels), perivascular macrophages (immune cells), and
tumor cells that produce the protein mena (increases ability of
cell to invade other cells) come into direct contact with one
another. When the three cells come into contact, they release
a protein which increases the permeability of the blood
vessels, allowing the cancerous cells to enter the bloodstream
[3]. However, it is most common for cancer to spread through
the lymph system because this system runs through the whole
body, as shown below.
The lymph system employs various mechanisms to
prevent malicious cells from entering the system. However,
when cancer cells enter the system, the lymph nodes, which
filter out infectious substances, start to swell up. At this stage,
under a high-powered microscope, the type of cancer cell,
such as breast cancer, becomes identifiable [4].
FIGURE 2 [4]
The lymph system.
Once cancer enters the lymph system, it can essentially
travel to any part of the body.
MicroRNAs Improve Upon Past Treatment Methods
In recent years, the methods for detecting and treating
cancer have vastly improved. In the past and still today,
doctors use medical imaging to detect cancer. Physicians use
x-ray imaging to check for the presence of breast cancer in
dense tissues as these tissues are more likely to contain
cancerous cells. However, x-ray images only visualize a
certain area of the breast and therefore, fail to accurately
depict the entire scope of the breast. Sonographies reflect
sound waves off the breast tissues and display an image of the
breast. This allows doctors to check for the presence of cancer
based on the developed image [5]. Like the x-ray,
sonographies also require a lot of time to process the image
and may not accurately depict all features of the breast where
cancer is present.
Currently, researchers at various universities are
investigating a simple, inexpensive blood test that can detect
cancer in the body by checking for the presence of
microRNAs. According to these researchers, microRNAs
control some of the major life processes by preventing genetic
code from executing. Since cancer cells are descendants of
healthy cells, which contain microRNAs, having too little or
too much of a particular microRNA can signify tumor growth
[6].
Researchers at the University of Michigan have created a
new method for detecting any sort of RNA from the blood.
Initially, researchers believed RNA only acted as a messenger
and carried out DNA’s genetic code to the proteins. However,
after sequencing the human genome, they discovered that
most RNAs do not act as messengers [6].
Scientists at this university hypothesize that when cancer
cells die, they release microRNAs and communicate with the
microRNAs to send them into the bloodstream as hormones.
In one experiment, researchers at the University of Michigan
coated a glass slide with “capture probes” and dropped
samples of solutions containing different types of microRNAs
onto the coated slides to detect microRNAs in the
bloodstream. To test whether the probes caught any
microRNAs, the researchers placed engineered fluorescent
DNA strands that bind to the microRNA and emit light when
bound to the microRNA onto the slides. This method is
efficient, reliable, and more direct than other cancer methods
[6].
Compared to medical imaging, extracting microRNA
from the blood offers a safe, inexpensive method of detecting
cancer in the blood. Certain types of medical imaging often
involve radiation, which can have negative side effects on the
body if absorbed in large doses, such as those used for cancer
treatment.
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Shivani Tuli
Similarly, miR-10 aids in the growth of breast cancer. An
overexpression of this type of microRNA can lead to a cancer
cell invasion as well as the spread of breast cancer. Like miR10, an overexpression in miR-21 signifies an increase in the
spread and growth of breast cancer cells [8]. Figure 3, below,
classifies the properties of several types of microRNAs as
either tumor suppressors or oncogenes.
MOLECULAR FUNCTION OF MICRORNAS
Cancer is a progressive disease and advances through the
body in many stages beginning with stage 1, which is
considered the benign stage, to stage 5, the most malignant
stage. During the benign stage, the tumor has yet to spread to
the rest of the body and is situated in one area where it can be
monitored. However, if not treated, the tumor can transform
undergoing a phenotypic change and spreading rapidly to the
rest of the body. Unlike other cells, cancerous cells can bypass
regulation by external growth signals, evade programmed cell
death, overcome replication limits, and form new tumors
through cell division [7].
There are two major categories of genes linked with
cancer: oncogenes and tumor suppressors, both of which are
protein coding genes. Oncogenes consist of growth factors,
apoptosis regulators, and signal transducers. Overexpression
of oncogenes, when activated by genetic alterations that
amplify the genes, can drive tumor development. Tumor
suppressors, on the other hand, dysregulate a tumor’s
functions to keep it from spreading and harming the body.
Essentially, oncogenes influence tumor growth while tumor
suppressors, as suggested by their name, suppress the tumor
and control the growth [7].
Recently, scientists have included microRNAs in their
definition of oncogenes and tumor suppressors. Classified as
a group of non-coding genes, microRNAs control gene
regulation and expression as well as regulate several
metabolic and cellular pathways, especially controlling cell
proliferation, differentiation, and survival [7]. MicroRNAs
regulate gene expression and depend on the internal and
environmental conditions at any given time. Since cancer is a
genetic disease that is affected by the alteration of a gene
expressed in the body, microRNAs in the body can
manipulate which genes are expressed in the body.
Until recently, scientists had no real concept of a
microRNA’s function in the body and what role the
microRNAs played in breast physiology. In an article about
the various functions of microRNAs, researchers conducted
an examination on different types of microRNA in mice. The
researchers then connected the different types of microRNA
to distinct phases of the breast cycle. From similar
experiments, scientists all over the globe mapped out the
different types of microRNA involved with breast cancer
[8].
Some types of microRNAs act as tumor suppressors,
whereas others act as oncogenes and aid in tumor growth. Let7, a family of 12 tumor-suppressing microRNAs, inhibits the
spread of cancer cells and represses key factors involved in
the growth of cancer. MiR-125a and miR-125b suppress cell
growth and favor apoptosis, the death of cells, in breast cancer
by targeting the messenger RNA that encodes the RNAstabilizing protein HUR, which acts as a marker in breast
cancer. However, this type of microRNA also has negative
responses toward breast cancer and in some mammals,
influences the growth of breast cancer [8].
FIGURE 3 [9]
Summarizes the different types of microRNA involved
with breast cancer.
Although microRNAs fulfill the role of both oncogenes
and tumor suppressor genes, scientists have yet to figure out
whether cancer causes the microRNAs to behave in a certain
manner or if the behavior is due to the cellular phenotype.
Since microRNAs can regulate multiple targets and specify
tissue expression, it is hard to classify them as just oncogenes
or just tumor suppressors [7]. To explore the full therapeutic
potential of microRNA, researchers first have to figure out
how microRNA regulates gene expression.
MECHANISMS OF BREAST CANCER
PATHOLOGY
As scientists research and experiment more with
microRNAs, the more they believe that microRNAs act as
promising biomarkers, a substance that indicates the presence
of a disease, of early stage breast cancer. Active microRNAs
can regulate gene expression by controlling the translation of
messenger RNAs during the DNA replication process.
Because the dysregulation of microRNAs is associated with
cancer, microRNAs are in a position to serve as potential
biomarkers for the diagnosis of breast cancer [10].
Unlike other detection methods, microRNAs can be
easily detected in biopsies. They are found in body fluids,
such as blood plasma (colorless fluid in the blood) and serum
(protein-rich liquid that separates from the blood when it
solidifies). Certain studies have shown that various types of
microRNAs can distinguish breast cancer cells from healthy,
normal cells [10].
Experiment on MicroRNA Profiling and Expression
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Megha Murthy
Shivani Tuli
that a microRNA’s expression profile changes as a result of
breast cancer. They compared the expression change result
they calculated from the study with five other data sets and
found similar results that supported their calculated results
[10].
This study shows how the expression of microRNA
relates to breast cancer. Different microRNA expressions
showed different microRNA regulation patterns in breast
cancer. This indicates that microRNA controls the gene
expression of cancer and that certain types of microRNA
either suppress the tumor or aid tumor growth. An
upregulation expression change indicates that the microRNA
contributes to cancer growth. A downregulation expression
change indicates that the microRNA helps suppress tumors.
Figure 5, below, identifies the gene regulation of several types
of microRNAs.
In one experiment at the Taizhou Central Hospital in
China between 2012 and 2013, researchers focused on the
profiling of microRNA expression associated with breast
cancer by examining the microRNA expressions of several
patients. The researchers accumulated fresh frozen breast
cancer tumors, adjacent normal tissues, and preoperative
serum from eight breast cancer patients who had undergone
surgery but had not been treated with chemotherapy. For a
control group, the researchers obtained a control serum
sample from eight healthy females [10].
After gathering the materials, the researchers isolated the
RNA (molecule responsible for coding through DNA
sequencing, decoding, expression of genes and carrying the
genetic code to the DNA) from each of the tissues and serum
samples using a Trizol reagent, which helps extract the RNA.
To eliminate biological variation, the researchers pooled
similar samples. They collected the RNA from the tumor cells
separately from the RNA from the tissue sample and the RNA
from the healthy cells [10].
The researchers at this university then sequenced and
aligned the RNA against a mature microRNA sequence and
observed the correlation, using the Pearson correlation
coefficient (the linear relationship or correlation between two
variables), between the two groups. Those microRNAs with a
q value (value after the data has been adjusted to exclude
insignificant differences in the data) of 0.8 were labeled as
significantly different from the rest of the microRNA [10].
FIGURE 5 [10]
This figure shows some types of microRNAs regarding
expression change.
The ability of microRNAs to regulate gene expression
has led to more research and studies about its potential in
cancer treatment as well as the role it plays in differentiating
between benign tumors and malignant tumors.
THERAPEUTIC POTENTIAL OF
MICRORNA IN BREAST CANCER
Experimenting with a microRNA’s ability to regulate
gene expression has led researchers and scientists to further
conduct research on the therapeutic treatment associated with
the different expressions of microRNAs. Based on the internal
and external conditions at any given time, microRNAs can
indicate which genes are actively expressed at a specific time.
In a recent study exploring the biogenesis of microRNAs,
researchers found out that patients with high levels of miR-21
expression were likely to have a poor therapeutic outcome.
This study concluded that certain chemotherapeutic drugs
might be more favorable depending on the particular
microRNA expression [8].
In a recent Ted Talk, Jorge Soto explained the ability of
microRNAs to easily detect breast cancer using their genetic
expression. He praised microRNAs stating that the approach
to detect cancer, “uses state-of-the-art molecular biology, a
low-cost, 3D-printed device, and data science to try to tackle
one of humanity's toughest challenges [11].” An individual
FIGURE 4 [10]
This figure depicts the correlation between the expression
profiles of serum from breast cancer patients and those
from healthy individuals (A) as well as the expression
profiles of breast cancer tumors and normal tissues (B)
Based on the high correlation between the breast cancer
serum and normal control serum, as depicted in the figure
above, the researchers, upon further examination, concluded
that the microRNAs may be released into the serum
selectively and the microRNA expression profile changes in
the tumor and serum as a result of breast cancer [10].
To predict the targets of the expressed microRNAs, the
researchers used an online database to obtain the target genes
whose expression changes coincided with a p-value of less
than or equal to 0.05 between the human breast cancer and
normal human breast. A p-value less than 0.05 signifies that
the results the researchers obtained is a significant indicator
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Megha Murthy
Shivani Tuli
who believes he or she has breast cancer doesn’t even need to
go to the hospital. In fact, they can go to their doctor and have
an RNA molecule extracted from their blood. The lab
technician extracting the RNA will place it on a plate which
will look for a specific microRNA that corresponds to the
extracted RNA expression. A smartphone is then placed onto
the plate and connected to a computer. The phone takes
several pictures and sends the pictures for interpretation and
processing on the online database. Within a 60-minute time
span, the database will match the extracted RNA with a
specific microRNA and analyze how much microRNA is in
the sample. The sample will then be compared to a specific
microRNA pattern and soon will reveal the type of cancer the
patient has [11].
The advantage of this method is that not only is it cheaper
and less time consuming than current methods involving
medical imaging, but it also detects the breast cancer in its
earlier stages rather than when the cancer is classified as a
stage 4 or stage 5.
Even though research is still being done to detect cancer
at an earlier stage, the ability of microRNAs to regulate genes
will aid in finding a definite treatment to cancer. At various
universities around the world, including the University of
Pittsburgh, professors are conducting breast cancer research
in their labs and researching the therapeutic potential of
microRNAs. In fact, Professor Partha Roy from the
University of Pittsburgh, Bioengineering Department at the
Swanson School of Engineering stated that polypeptide
chains and lipids that enclose microRNAs can cause target
action on cancer cells and potentially treat cancer [12].
Antagomirs, chemically engineered oligonucleotides,
involve microRNA modulation to treat breast cancer. In a
study done with mice to test out antagomirs, researchers
injected the antagomirs into the liver of the mouse. The
researchers observed that the antagomir inhibited the
expression of a type of microRNA in the liver [7]. Figure 6
depicts how an active antagomir blocks the microRNA in
order to inhibit its oncogenic properties.
FIGURE 6 [13]
This figure shows how antagomirs can block microRNA.
By inhibiting microRNA expression, antagomirs can
essentially prevent microRNAs with oncogenic properties
from spreading the tumor throughout the body.
Although research is still being done on the microRNA’s
potential in cancer treatment, additional research, as
articulated in the article written by Sonia Melo, has shown
that the use of microRNAs can sensitize tumors to
chemotherapy. Currently, there is still no cancer treatment
that is 100% effective against cancer. Although chemotherapy
has been successful with some patients, some patients require
multiple doses of chemotherapy treatment. The only problem
with this is that the more sessions of chemotherapy the patient
undergoes, the more the body resists the treatment. One of the
few obstacles to a successful cancer treatment using
chemotherapy is resistance to chemotherapy with increased
chemotherapy exposure. MicroRNAs can alleviate this
problem because of their ability to target multiple messenger
RNA molecules involved in the signaling pathways that are
damaged by cancer. Since multiple microRNAs can target a
given gene, the successful outcome of microRNA therapy
depends on the number of targets and the affinity of those
targets to the microRNA. The microRNA has to target the
appropriate gene based on its own expression in order to avoid
unwanted side effects [14].
Overall, microRNAs have the potential of detecting and
treating cancer. There are several treatment and detection
methods involving microRNAs that enable certain genes to be
either activated or suppressed depending on the gene
expression of the individual microRNA. They can also aid in
alleviating resistance to chemotherapy and essentially play a
significant role in cancer therapy.
ETHICAL CONCERNS ABOUT USING
MICRORNAS
Several ethics committees around the globe have
approved of using microRNAs in cancer research and cancer
treatment. However, there are still various factors to consider
when working with microRNAs surrounding the ethics of the
research.
Arguments Against Using microRNAs to Treat Breast
Cancer
Currently, the use of microRNAs isn’t available for
clinical applications. For them to be used in a clinical setting,
there are certain limitations that medical authorities need to
look into. Research has shown that an overexpression of
microRNAs in the body is an acceptable indicator for the
presence of breast cancer in the body. However, researchers
need to determine the “normal” levels and diversity of
microRNAs in body fluids. To determine how much
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Shivani Tuli
microRNA accounts for overexpression, it’s important to
indicate the normal amount of microRNAs in the body [7].
When looking at the diversity of microRNAs in the body,
it’s important to account for factors such as race, gender, and
age. The “normal” level of microRNA in a 50-year-old female
might be different than the “normal” level of microRNA in an
18-year-old male. MicroRNA profiling approaches for body
fluid samples has to be universal to ensure that there are no
dramatic changes in the microRNA expressions [7].
Regarding microRNA expressions, when using
antagomirs to inhibit specific microRNA expressions, it’s
important to first understand which microRNAs correspond
to which expressions. If an antagomir that inhibits a tumor
suppressing microRNA is created, then using antagomirs to
treat cancer will have the opposite effect. The antagomirs will
advance the growth of the tumor since it just inhibited the
microRNA that suppresses the growth of the tumor. In
addition, antagomirs have only been tested on animals and not
on humans. Scientists have yet to determine the effects of
injecting antagomir into the human body. Since humans have
an immune system, there is no way to tell yet whether the
effects of antagomirs on the human body will be useful if
human immune system fights the antagomirs [7]
Although there are several concerns with using
microRNAs in treatment, there are more concerns with
actually conducting an experiment involving microRNAs.
To get accurate results, the sample size has to be
consistent with all the studies completed. Some experiments
studied a small number of patients and healthy individuals,
whereas other studies examined a large group of patients and
a large control group. In this case, the statistical analysis per
group will be different and there will be no basis to compare
results. In a statistical study, it is always best to have a large
sample choice to avoid significant differences in the data [15].
While preparing the sample used for microRNA
detection, it’s important to be consistent with the extracted
sample. Some experiments have extracted whole blood
samples, or whole serum and plasma samples. Whole blood
samples include different cell types, such as white blood cells,
red blood cells, and platelets, which could alter the results and
yield inaccurate results. In this case, it is better to use serum,
which contains the liquid portion of blood mixed with the
proteins, and plasma, which contains a liquid portion of blood
along with proteins, some molecules, and some cells.
However, these samples can affect the data as well, since
there is a higher concentration of microRNAs in cells. There
also appears to be a higher concentration of microRNA in
serum than in plasma which would cause difficulties when
comparing data with a different starting material. In data
analysis, it is often difficult to choose a reference microRNA
to compare results with [14].
Prior to the discovery of microRNAs’ therapeutic
potential in cancer, scientists believed microRNAs were
useless molecules in the body. However, after extensive
research, scientists determined the microRNA’s ability to
regulate genes in the body. This discovery has provided new
opportunities for research as well as a new perspective
towards gene expression. Not only are scientists looking at the
gene expression of microRNAs, but they are looking at other
genetically engineered molecules, such as antagomirs, that
can potentially inhibit the negative effect of microRNA in the
body. Discovering the true potential of microRNAs has
allowed scientists and researchers to take a second look at
other molecules they initially deemed as irrelevant in the
body. This discovery will give medical professionals another
chance to research a cure for a disease they initially had no
cure or treatment for.
MicroRNA research offers hope to patients with cancer
and other “untreatable” diseases. Since microRNAs can target
several genes at once, they can regulate several cancer genes
at once on several different pathways. Data also indicates that
several types of microRNAs, such as Let-7, yield successful
results when it comes to suppressing tumors. This microRNA,
especially, has shown, in numerous studies, that it reduces the
proliferation of tumorous cells and increases the apoptotic
activity of tumor cells. In the past decade, several types of
microRNAs have been discovered and are awaiting clinical
use. Although not every type of microRNA is approved for
clinical use in the human body, some types have been
approved for use on some animal models, such as mice. Once
more research has been done on animal models, there is a
chance that using microRNA to suppress tumors or for other
research will be approved for clinical use in humans [16].
The therapeutic potential not only has its uses in treating
cancer but also has useful applications in cancer stem cells.
Cancer stem cells are defined as “a small fraction of cancer
cells that have the ability to self-renew and give rise to
identical daughter cells [16].” These cells are often labeled as
the root cause of tumors and actually are more resistant to
therapy than normal cancer cells. This is likely the reason why
patients grow resistance to chemotherapy after prolonged
exposure. Since various types of microRNAs express
different patterns, it is highly likely that there are types of
microRNA that can inhibit the spread of cancer stem cells.
Discovering and conducting research on different types of
microRNAs in the body will help prevent chemoresistance
and increase the success rate of chemotherapy in patients [16].
Although there are various concerns about conducting
research and the general ethics surrounding research, the
positive effects of microRNA in preventing the spread of
cancer and treating cancer outweigh those research concerns.
FUTURE DIRECTIONS
Positive Responses Toward Using MicroRNAs to Treat
Breast Cancer
As the most common type of cancer, breast cancer
continues to affect millions of women worldwide. Although
there are ways to detect and treat this disease, the success rate
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for available treatments isn’t as high as it could be. Current
methods of detection and diagnosis including x-ray imaging,
sonography machines, and mammograms, detect the disease
at a very late stage when chemotherapy is the only treatment
that has a chance of being successful. To solidify a definite
treatment for cancer, cancer has to be detected at an earlier
stage.
MicroRNAs enable physicians to detect cancer at an
earlier stage, giving them more time to find a better treatment
with a higher success rate. Detecting cancer using
microRNAs is as easy as getting a blood test. Not only are the
results available in less than an hour, the process is also
inexpensive. Apart from detecting cancer, microRNAs also
have the potential to treat cancer based on the patterns of
expression. Already, hundreds of types of microRNAs have
been discovered, each with its own unique expression and
pattern. Since each cancer is different, each type of
microRNA can target different cancerous genes and
manipulate them to stop spreading throughout the rest of the
body.
Since the discovery of microRNAs’ therapeutic potential
towards treating breast cancer, additional research has been
conducted on other molecules that may help treat other
diseases. In fact, microRNAs don’t only help treat and detect
cancer; they also have potential in treating other diseases,
such as heart disease and Hepatitis. Although scientists
haven’t fully ventured into the therapeutic potentials of
microRNA to treat other diseases, there is a possibility, based
on gene expression, that microRNA can cure other genetic
diseases.
Understanding how gene expression works and
understanding the cellular pathways in the body will open up
new opportunities for genetic research. The future seems
bright for finding a cure for cancer with the discovery of
microRNAs and similar molecules. In the future, the number
of people who acquire cancer will hopefully decrease and
within the next few decades, there most likely will be a better
treatment for cancer involving the use of microRNAs rather
than chemotherapy and other radiation inducing treatments.
There is still a long way to go in cancer research, but with
each passing day, there is a new discovery on how best to treat
this disease. Scientists are working hard to find a cure and
soon, with the help of microRNAs, cancer will be a curable
and treatable disease.
MicroRNAs can also treat cancer and increase the success rate
of chemotherapy since several types of microRNAs can
prevent resistance to chemotherapy. There are so many types
of microRNAs out there that still need to be discovered that
potentially have therapeutic properties and will benefit the
public health.
Before scientists began conducting research on the
mechanisms of microRNAs, they believed these molecules to
be insignificant molecules of the human body. However, after
discovering that microRNAs play a significant role in the
growth and suppression of pathogens, scientists, researchers,
engineers, and other professionals involved in the medical
field, sought out to explore the therapeutic and harmful effects
of these small molecules.
Medical authorities were most interested in the therapeutic
potential of microRNA to detect and treat cancer. Finding a
treatment to cancer would benefit several individuals,
especially those who suffer from cancer or those who know
others who either suffer from cancer or have passed away
from cancer. Now that scientists know that microRNAs can
regulate gene expression and can suppress or accelerate tumor
growth, scientists can combine these abilities with drugs and
multidrug therapy to create a more efficient treatment. Since
many diseases are controlled by multiple pathways,
microRNAs can target these multiple pathways because of
their ability to target multiple genes simultaneously [17].
Combining the use of microRNA to combat cancer with
drug therapy would make cancer treatment more effective
because it would reduce the risk of several side effects of
certain drugs. However, to combine the use of microRNA
with drug therapy, scientists would have to experiment more
with how drug treatment influences microRNA gene
expression. By understanding the relationship between drug
treatment and microRNA gene expression, scientists can
pinpoint the most appropriate microRNAs to target based on
whether they’re oncogenes or tumor suppressors. Depending
on the type of microRNA, the drug will either aid the
microRNA in suppressing the tumor or inhibit the microRNA
from aiding in the spread of the tumor [17].
Once enough microRNA research has been conducted in
laboratories, the practice can be used to clinics where it will
be more widely accessible to people. Moving the practice to
clinics will benefit the public health. MicroRNAs are
considered a “top candidate for the next generation of
biomarkers” [18] because they are more likely to lead to early
detection of cancer than proteins or other molecules.
MicroRNA biomarkers are also more likely to be discovered
by genomic tools, which would make it easier to detect cancer
earlier. As more appreciation grows for microRNA research,
the more research scientists, researchers, and engineers can
conduct to improve upon this technology and help save lives.
Since there are several types of microRNAs in the body,
each with their own unique gene expression, there is a
possibility that several of these microRNAs have properties
that will have therapeutic properties. Experimenting and
Sustainability of MicroRNAs
Sustainability involves providing health benefits and
improving the quality of life. Defining a technology, such as
microRNAs, as “sustainable” means improving human
health. Using microRNAs to detect and treat cancer has to be
safe and has to have a positive impact on the individual rather
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7
Megha Murthy
Shivani Tuli
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ACKNOWLEDGEMENTS
Megha Murthy would like to thank her dad for editing
this paper and supporting her through the writing process. We
would both like to thank our families for supporting us while
writing this paper. We would also like to thank the Swanson
School of Engineering for assigning this paper because it
really helped improve our research paper writing skills. We
would also like to thank our co-chair and chair for making
sure we’re on the right path and checking up to make sure that
we meet the deadline for this paper.
8