Water bears' 'superpower' could be used to treat cancer

Researchers from Harvard Medical School and the University of Iowa have shown that the Dsup (damage suppressing) protein in tardigrades, which protects DNA from radiation, can be transported into human cells via mRNA.

While radiation therapy destroys cancer cells, it also damages healthy cells, causing DNA breakage, cell death and inflammation. This can cause patients to experience serious side effects, ranging from mouth sores to significant weight loss and even pain that requires hospitalization, says James Byrne, a radiation oncologist at the University of Iowa.

Tardigrades are known for their ability to withstand extreme conditions. They can survive oven temperatures, withstand immense pressures, and remain unharmed even when exposed to radiation levels that would kill humans. This is mainly because they are able to protect their DNA from the effects of radiation thanks to the Dsup protein.

When scientists tested the protein in human cells in 2016, they discovered that it reduced DNA damage caused by X-rays by 40 percent. However, direct protein injection was not practical because Dsup had to enter the cell nucleus directly.

Now, researchers have proven that they can temporarily deliver Dsup into cells using mRNA technology, a method considered much safer than DNA editing procedures as it does not carry the risk of permanently altering the genetics.

The researchers injected the mRNA version of Dsup into cells in a laboratory environment by placing it in special polymer-lipid nanoparticles. This way, once the cells had finished producing the protein, the mRNA would be broken down and destroyed. Crucially, a mechanism was created to ensure that the Dsup protein only protected healthy cells and did not provide an advantage to cancerous cells.

Experiments were also conducted on mice. Six hours after being injected with Dsup mRNA, the mice were given radiotherapy. The results were striking:

• DNA breaks were reduced by 50% in mice given radiation to the intestinal area.
• This rate was measured as 33% in mice that were irradiated to the mouth area.
• Dsup protection did not affect the growth of tumor cells, meaning it only protected healthy cells.

The researchers note that this technology could not only protect healthy cells during radiotherapy, but could also be used in other medical fields such as chemotherapy and genetic diseases to make DNA more resistant to damage.

In addition, it is thought that it can be used as a protective method for astronauts exposed to space radiation or in situations that pose a risk of nuclear radiation.

This exciting work has been published in the journal Nature Biomedical Engineering and is expected to pave the way for larger-scale clinical trials in the future.