Researchers on the University of Tokyo have used artificial DNA to focus on and kill cancer cells in a totally recent way. The strategy was effective in lab tests against human cervical cancer- and breast cancer-derived cells, and against malignant melanoma cells from mice. The team created a pair of chemically synthesized, hairpin-shaped, cancer-killing DNA. When the DNA pairs were injected into cancer cells, they connected to microRNA (miRNA) molecules which can be overproduced in certain cancers. Once connected to the miRNA, they unraveled and joined together, forming longer chains of DNA which triggered an immune response. This response not only killed the cancer cells but prevented further growth of cancerous tissue. This method is different from conventional anticancer drug treatments and is hoped to bring a few recent era of drug development.
Cancer is a sadly familiar global health concern and current methods of treatment have their limitations. Nonetheless, drugs based on nucleic acids -; namely DNA and RNA, the vital information-carrying molecules -; can control the biological functions of cells, and are expected to remodel the long run of drugs and supply a big boost towards efforts to beat cancer and other hard-to-treat illnesses, brought on by viruses and genetic diseases.
A research group on the University of Tokyo, led by Assistant Professor Kunihiko Morihiro and Professor Akimitsu Okamoto from the Graduate School of Engineering, were inspired to create a recent anticancer drug using artificial DNA.
We thought that if we are able to create recent drugs that work by a unique mechanism of motion from that of conventional drugs, they could be effective against cancers which have been untreatable to this point.”
Professor Akimitsu Okamoto, Graduate School of Engineering, University of Tokyo
Nucleic acid drug use for cancer treatment has been difficult since it is difficult to make the nucleic acids distinguish between cancer cells and other healthy cells. This implies there’s a risk of adversely affecting the patient’s immune system if healthy cells are inadvertently attacked. Nonetheless, for the primary time, the team was in a position to develop a hairpin-shaped DNA strand that may activate a natural immune response to focus on and kill specific cancerous cells.
Cancer cells can overexpress, or make too many copies of, certain DNA or RNA molecules, causing them to not function normally. The team created artificial oncolytic (cancer-killing) hairpin DNA pairs called oHPs. These oHPs were triggered to form longer DNA strands after they encountered a brief (micro) RNA called miR-21, which is overexpressed in some cancers. Typically, oHPs don’t form longer strands as a consequence of their curved hairpin shape. Nonetheless, when the factitious oHPs enter a cell and encounter the goal microRNA, they speak in confidence to mix with it and form an extended strand. This then causes the immune system to acknowledge the presence of the overexpressed miR-21 as dangerous and activate an innate immune response, which ultimately results in the death of the cancer cells.
The tests were effective against overexpressed miR-21 present in human cervical cancer-derived cells, human triple-negative breast cancer-derived cells, and mouse malignant melanoma-derived cells. “The formation of long DNA strands as a consequence of the interaction between short DNA oHPs and overexpressed miR-21, found by this research group, is the primary example of its use as a selective immune amplification response which might goal tumor regression, providing a recent class of nucleic acid drug candidates with a mechanism that is totally different from known nucleic acid drugs,” said Okamoto.
“The outcomes of this study are excellent news for doctors, drug discovery researchers and cancer patients, as we consider it is going to give them recent options for drug development and drugs policies. Next, we’ll aim for drug discovery based on the outcomes of this research, and examine intimately the drug efficacy, toxicity and potential administration methods.” This research still has many steps to go before a treatment will be made available, however the team is confident in the advantages of nucleic acids for brand new drug discovery.