CRISPR: Revolutionizing Cancer Treatment and Research
Introduction:
Ever since it was discovered that even a small change in a single genome can be a severe cause
for cancer and other health hazards, it has been a competition to search for the easiest way to
correct those unwanted changes in DNA segments. Many ways have been developed until
now, but none of them matches our requirements. But to bring revolution in the health and
research sector in 2013, occurred a gene editing tool named CRISPR.
CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) is a groundbreaking tool in
the field of genetics. It enables scientists to edit genomes with remarkable precision, essentially
acting as molecular scissors (Restriction enzymes: used to cut DNA from specific sequence) that
can alter DNA sequences. The technique is derived from a natural defense mechanism found in
bacteria, where they use CRISPR sequences to recognize and combat invading viruses.
CRISPR uses a system that naturally occurs in bacteria, where it acts as a defense against virus.
Scientists adapted this mechanism for genome editing. It includes:
● Guide RNA: It guides the system to specific parts of DNA that requires editing
● Cas9 Enzyme: A protein that cuts DNA at the desired location
● Repair Mechanism: Once cut, the cells try to repair the DNA during which the scientist
can manipulate the process.
CRISPR is used in various fields ranging from Genetic disease treatment to improving crops. In
Genetic Disease treatment it is used in Sickle cell anemia, cystic fibrosis, and Muscular
dystrophy. For improving crops, it is used to Increase yield, to reduce the amount of pest
attacks and to for drought tolerance. Other applications include biotechnology, genetic editing,
genetic regulation and genetic therapy.
How does CRISPR edit genes?
Now, CRISPR is being widely used as a mainstream method in Cancer Biology. The enzyme
called Cas9 Nuclease, binds with the gRNA or guide RNA a structure of 20 nucleotide sequence
that matches the target DNA, guides Cas 9 enzyme to the target DNA. The PAM (Protospacer
Adjacent Motif) sequence serves as the binding site for CRISPR Cas 9 enabling it to locate and
The above given figure shows how CRISPR
acts on the target DNA. First image shows the
structure of CRISPR Cas9 based gene editing
tool with gRNA. The second picture indicates
that the Cas9 enzyme has banded with the
target DNA. Third picture shows that the gene
is cut and the fourth and the last picture
indicates that the cell is repaired and the new
DNA segment has been formed.
bind with the target DNA initiating DNA cleavage.
Methodology for Fighting Cancer
For treating , different types of cancer one approach is to target oncogenes, they are the
mutated genes that have the ability to cause cancer with normal proliferation and growth.
Once the mutated oncogene is identified , the researchers develop a specific gRNA to bind with
the mutated gene. MYP is an oncogene which is vigorously active in various types of cancers, to
prevent the growth of tumors and progress of cancer cells in one’s body, it is brought to an
inactive state.
Another way leads to the correction of those cells which regulates the immune response of our
body. These techniques enable the installation of cytokines and immune mediators. For
example, researchers use CRISPR to suppress the PD 1 protein, which acts as an immune
checkpoint on the T cells of our body. After these T cells become more capable of regulating our
immune response, they start attacking contaminants or cancer-causing cells in our body. Cas 9
can also be used in immunotherapy to edit T cells an NK cells to increase their efficacy and
precision to target the cancer cells.
Besides, the gene – editing technique can also be used to treat the genetic mutations that are
the cause of cancer by utilizing CRISPR-mediated repair methods HDR (Homology-directed
repair) and NSEJ (Non-homologous end joining). HDR uses a donor template to induce desired
genetic changes, but it is not efficient as NSEJ; it brings the desired changes without using a
template.
Impacts of CRISPR around various parts of the world- Statistics
CRISPR’s impact on Cancer treatment is still being explored.
Success rates in gene editing- CRISPR-mediated gene editing has shown efficiency rates ranging
from 50%-90% in experimental setups. This varies depending on the type of cells that is being
edited and the target.
Clinical Trials- Over 100 clinical trials worldwide are testing CRISPR-based therapies exploring
its various impacts on different genes and on different people.
Market Trends- The global CRISPR technology market was valued at $3.2 billion in 2023 and is
projected to grow to $15 billion by 2033. This growth reflects increasing investments in CRISPR
research and its potential applications in medicine.
Leading CRISPR startups varies from Beam Therapeutics, Editas Medicine, Synthego and many
more.
CRISPR was used by many scientists during COVID-19 in order to find solutions to many of the
problems that had arisen:
● Rapid Diagnostic Testing: Two systems mainly Sherlock Biosciences’ SHERLOCK (tm)
(Specific High Sensitivity Enzymatic Reporter Unlocking) and Mammoth Biosciences’
DETEC TR (tm) systems from Mammoth Biosciences were developed in order to to
detect the DNA faster and more accurately.
● Understanding the Pathogenesis: Was used to identify potential drug targets
● Surveillance of Virus: This was used to track the spread of the variants and to potentially
change the infection and find a proper cure.
Terrific Results, but still Facing Obstacles
The preclinical results of this have been really terrific, but to implement it as an operable
clinical option there are still many obstacles awaiting such as:
Delivery limitations: The CRISPR Cas9 enzyme have to be delivered to the cell at the correct
point and at the correct time of the cell cycle. CRISPR Delivery methods include electroporation,
lipofection, viral plasmids, microinjections and nanoparticles.
Off-target effects: This is the major concern for Cas9 nuclease. If the untargeted part of the
genome is altered it can cause other health issues or even cancer. Improvisation is being done
in silica off-target tools and Cas9 enzyme.
Efficiency limitations: The repair methods of the double stranded cut in the gene are not
efficient enough and the targeted genomes can carry modifications that can delete the
targeting vector.
Potential Solutions to Overcome these Issues
To Improve delivery methods:
1. Using nanoparticles: Can enhance precision and reduce toxicity. They can be
engineered to target specific cells and release CRISPR components at the right time.
2. Viral Vectors: Modified viruses, such as adeno-associated viruses (AAVs), are being
optimized for safer and more efficient delivery.
3. Microinjections: Useful for localized delivery (e.g.: Eye, brain)
To Enhance Efficiency
1. Alternate Repair Pathways: Researchers are now exploring homology-independent
repair mechanisms to improve the accuracy of DNA repair.
2. Base Editing: Instead of cutting DNA, base editing allows for precise changes to
individual nucleotides, reducing the need for double-strand breaks.
3. Prime Editing: This newer technique enables more accurate and versatile genome
editing without relying on traditional repair pathways.
4. Enhance HDR Pathways: Developing strategies to upregulate the activity of cellular HDR
machinery.
In Conclusion:
CRISPR is undeniably one of the most transformative tools in modern science. Originating from
a bacterial immune defense, it has been adapted into a precise genome-editing technology that
is reshaping medicine, agriculture, and biotechnology. Its potential applications include curing
genetic disorders, advancing cancer therapies, and enhancing crops, all while opening new
doors to scientific exploration.
Glossary:
● Binding Site: In biochemistry and molecular biology, a binding site is a region on a
macromolecule such as a protein that binds to another molecule with specificity. The
binding partner of the macromolecule is often referred to as a ligand.
Macromolecule- Large organic molecule that form by polymerization.
● Cystic Fibrosis: A faulty gene is the cause of the hereditary condition known as cystic
fibrosis. It impacts the digestive system, lungs, and other organs. Lung infections,
stomach issues, and trouble breathing can result from thick mucus clogging airways.
Over time, the illness gradually harms a number of organs.
● HDR (Homology-directed repair): Homology-directed repair (HDR) is a crucial cellular
mechanism in eukaryotes that uses a homologous sequence as a template for precise
DNA repair, often used in CRISPR-mediated gene editing to introduce specific DNA
sequences, with homologous recombination being the most common form.
● Muscular Dystrophy: Muscular dystrophy is a group of genetic diseases that cause
progressive weakness and loss of muscle mass. In these conditions, abnormal genes
(mutations) interfere with the production of proteins needed to form healthy muscles.
● NSEJ (non-homologous end joining): Non-homologous end joining is a pathway that
repairs double-strand breaks in DNA. It is called "non-homologous" because the break
ends are directly ligated without the need for a homologous template, in contrast to
homology directed repair (HDR)
Citations:
1. https://media.market.us/crispr-statistics/- Trishita Deb,2025
2. https://www.cancer.gov/news-events/cancer-currents-blog/2020/crispr-cancer-
research-treatment- 2020
3. https://pmc.ncbi.nlm.nih.gov/articles/PMC10046289/- Basel, 2023
4. https://cancerbiologyresearch.com/how-crispr-is-revolutionizing-cancer-treatment-
what-you-need-to-know/#technical-challenges-and-potential-risks- Mohammed, 2024
5. https://www.frontiersin.org/journals/oncology/articles/10.3389/fonc.2020.01387/full-
2020
6. https://news.stanford.edu/stories/2024/06/stanford-explainer-crispr-gene-editing-and-
beyond- Stanford Report, 2024
