Artificial DNA: How they help destroy cancerous tumours through ‘cell death’
Highlights
- New study shows how new therapy using synthetic DNA triggers tumour cell death.
- A technique known as ‘selective immune amplification response’ is found to be effective against 3 types of cancer.
Ways to crush cancer cells are advancing fast. This is thanks in part to breakthroughs in computing power and advances in molecular manipulation at the DNA level.
A new study led by Japanese scientists advances cancer research through the use of artificial DNA, or "synthetic DNA" that leads cancer cells to self-destruction.
What’s new in the therapy is that the techniques doesn’t try to "crush" cancer cells directly. Instead, it uses DNA nanotechnology, which involves the design and assembly of artificial DNA structures to deliver therapeutic agents to cancer cells.
It can be used in combination with other therapies to treat at least three forms of cancer, researchers said.
The research is poised to make a difference in cancer research in at least two ways:
(1) It found the formation of long DNA strands — due to the interaction between short DNA oHPs and overexpressed miR-21 — as the first example of its use as a “selective immune amplification response” (SIAR), a technique that allows specific tumours to be targeted.
(2) This provides a new class of nucleic acid drug candidates with a mechanism that is completely different from known nucleic acid drugs, researchers said.
What the tests found
The research group which started the work to create a new anti-cancer drug using artificial DNA at the University of Tokyo was led by Assistant Professor Kunihiko Morihiro and Professor Akimitsu Okamoto from the Graduate School of Engineering. Here's what the researchers found:
- The tests were effective against “over-expressed” miR-21 found in human cervical cancer-derived cells, human triple-negative breast cancer-derived cells, and mouse malignant melanoma-derived cells.
- The study results offer good news for doctors, drug discovery researchers and cancer patients, in a number of ways:
(1) It will give them new options for drug development and medication policies.
(2) New discovery based on the results of this research will aid in drug research.
(3) Further research is needed to test in detail the drug efficacy, safety, dosage and potential administration methods.
The researchers thought that if they can create new drugs that work by a different "mechanism of action" from that of conventional drugs, they may be effective against untreatable cancers.
More studies needed
The research needs various steps, including clinical trials (on humans) before a treatment can be made available and go through approval process.
Though follow-up studies are needed to take it forward, the Japanese researchers are confident in the benefits of the therapy for new drug discovery.
What is selective immune amplification response (SIAR)?
It refers to a strategy in cancer immunotherapy that aims to selectively enhance the immune response against cancer cells. This is achieved by targeting specific molecules — or pathways — that are involved in the immune system's recognition and attack of cancer cells.
Some types of immunotherapy only target certain cells of the immune system. Others affect the immune system in a general way.
Targeting specific cells
The idea behind SIAR is to overcome the mechanisms that allow cancer cells to evade the immune system.
For example, some cancer cells have mutations in genes that code for proteins that are recognised by the immune system as foreign or abnormal.
Another way to selectively amplify the immune response against cancer cells is to target specific immune cells, such as T-cells or natural killer cells, and enhance their function or survival.
This can be done by using drugs that block inhibitory signals or enhance activating signals that are involved in the regulation of immune cell activity.
The ultimate goal of SIAR is to increase the effectiveness of cancer immunotherapy by making the immune system more effective in recognising and destroying cancer cells — essentially boosting one’s immune system to recognise and fight cancerous cells.
What are the prospects for SIAR?
The field of selective immune amplification response is an active area of research. It holds promise as a new way to treat cancer and improve patient outcomes, though it’s still in the early stages of development.
Overall, the field of selective immune amplification response is still in its early stages, and more research is needed to fully understand the potential of this approach for treating cancer.
However, the results from early-phase clinical trials are encouraging and suggest that this approach holds promise for the future.
What other cancer therapies are being investigated?
There are several clinical trials underway to test the safety and efficacy of various strategies to enhance the immune response against cancer cells.
In 2021, studies were focusing on the use “checkpoint inhibitors”, which are drugs that block inhibitory signals on immune cells, to enhance the immune response against cancer.
Other studies were exploring the use of cellular therapies, such as CAR-T cell therapy, to directly target and kill cancer cells.