Stiletto-shaped DNA molecules help cure cancer
Japanese scientists have presented a new method of cancer treatment. Artificial molecules "warn" the immune system of the presence of cancer cells and help the body fight.Geneticists from the University of Tokyo have developed a DNA-based cure for cancer. Preliminary studies have confirmed its effectiveness against human cervical and breast cancer cells in laboratory trials, and against melanoma in an experiment on mice.
Nucleic acid-based drugs have difficulty distinguishing healthy cells from cancer cells. This leads to dangerous immune reactions due to "false" triggers. To overcome this problem, researchers have developed artificial DNA in an unusual shape - in the form of hairpins. They fixate only on molecules that are actively expressed only in cancer cells and trigger a strong immune response.
In creating the drug, scientists synthesized two DNA molecules, each twisted in the shape of a hairpin. They named the invention oHP (short for oncolytic hairpins).
The oHPs are sensitive to miR-21, a microRNA that is actively expressed in certain types of cancer cells. When "hairpins" meet such RNA, all three molecules combine. And, as a result of a series of successive fusions, one large long DNA is formed. Such a molecule becomes "visible" to the immune system, and the body begins to fight against cancer cells.
The researchers tested their drug in vitro ("in vitro") on cell cultures grown from human cervical and breast cancer cells and in vivo ("in living cells") on laboratory mice. In all cases, oHPs not only helped destroy tumors, but also prevented further growth of cancerous tissue. The researchers plan to conduct additional safety testing of the drug before starting human clinical trials.