Hail to the Hardy Tardigrade

Recent studies have explored how the tiny tardigrade, a microscopic organism renowned for its resilience (also known as the “water bear”), can inspire new cancer treatments. Researchers from MIT, Brigham and Women's Hospital, and the University of Iowa developed a novel approach to protect cancer patients from the adverse effects of radiation therapy by leveraging the damage suppressor protein (Dsup) produced by tardigrades. mRNA was introduced to encode the Dsup protein into mice, prompting cells to produce it transiently. Cells engineered to express Dsup exhibited increased resistance to radiation, suggesting potential applications in protecting healthy tissue during cancer treatments. The mRNA delivery was facilitated using specially designed polymer-lipid nanoparticles, optimized for targeting specific tissues such as the colon and mouth.

Senior author James Byrne, an assistant professor of radiation oncology at the University of Iowa, said, “[Radiation] affects a huge number of patients, and it can manifest as something as simple as mouth sores, which can limit a person’s ability to eat because it’s so painful, to requiring hospitalization because people are suffering so terribly from the pain, weight loss, or bleeding. It can be pretty dangerous, and it’s something that we really wanted to try and address,”

The findings suggest that this method could potentially mitigate the side effects of radiation therapy in cancer patients, particularly those undergoing treatment for head, neck, and gastrointestinal cancers, where radiation often harms adjacent healthy tissues.

Tardigrades are influencing other areas of medical research too. Research has identified tardigrade proteins capable of inducing a state of suspended animation, or biostasis, in human cells. These proteins form gels that slow down cellular metabolism, making cells more resistant to stressors such as radiation. This reversible process holds more promise for developing therapies that protect healthy cells during cancer treatments. 

A newly discovered tardigrade species has also provided insights into the genetic mechanisms behind their radiation resistance. Genes such as TRID1 and DODA1 have been identified, which contribute to efficient DNA repair and the production of antioxidant pigments, respectively. These findings could inform strategies to enhance human cell resistance to radiation, potentially improving cancer therapies.

Senior scientists Silvia Sanchez-Martinez at the University of Wyoming’s Department of Molecular Biology describes the tardigrade as having unique “superpowers.” She says: “They can survive in extreme environments, for example, in high temperatures, they can survive freezing, and they can survive high pressures.” Species of tardigrade have been found in diverse environments such as at the bottom of the ocean or on mountain tops. Famously, tardigrades have even returned to life following exposure to the vacuum of space. 

They can also survive exposure to a thousand times more radiation than humans, Sanchez-Martinez adds, which explains the interest of the cancer treatment development sector. She foresees potential applications in the preservation of pharmaceuticals and biologics using tardigrade “gels” that can slow down metabolism in human cells.

Inspiration for medicinal development has always been found through the lens of a microscope. But when a microscopic water bear walks across a slide, as part of its epic journey from the depths of the ocean to the cold of space, we will continue to watch and wait for the big things to happen.