News — Beyond hard workers and aides, the domestic dog (Canis lupus familiaris) can also help us learn about cancer. It turns out that man’s best friend falls ill and fights off cancer more similarly to humans than the common laboratory mouse. Surprisingly, this makes studying their wilder cousins, the gray wolf (Canis lupus), an excellent choice to understand how we might treat cancer one day. Esoteric and challenging, scientists can’t just go out and survey the neighborhood wolf pack for answers. Instead, they have to go where wolves and cancer are sure to collide.
In 1986, a nuclear reactor at the Chernobyl power plant exploded, releasing cancer-causing radiation and irradiated debris into the environment, and resulting in the world’s worst nuclear accident. The Chernobyl Exclusion Zone (CEZ) is a 1000 mi2 parcel of the surrounding area chronically exposed to radiation and abandoned by people. Yet wildlife like horses, wolves, forests, and fungi have recolonized. Cara Love, an evolutionary biologist and ecotoxicologist in Shane Campbell-Staton’s lab at Princeton University, has combined her passion for conservation and nature-based solutions to study how the wolves of Chernobyl survive and thrive despite generations of exposure and the accumulation of radioactive particles in their bodies.
In 2014, Love and colleagues went to the CEZ, radio-collared wolves, and took blood to understand the wolves’ responses to cancer-causing radiation. Using these specialty GPS collars armed with radiation dosimeters, “we get real time measurements of where they are and how much [radiation] they are exposed to,” said Love. They discovered that Chernobyl wolves are exposed to upwards of 11.28 millirem of radiation everyday for their entire lives, over 6 times the legal safety limit for the average human worker.
Unlike wolves living exclusively outside the CEZ, Love found that Chernobyl wolves have altered immune systems, similar to cancer patients undergoing radiation treatment. And most promising, she has identified specific regions of the wolf genome that seem resilient to increased cancer risk. Most human research has found mutations increasing cancer risk (like BRCA does with breast cancer), but Love's work hopes to identify protective mutations that increase the odds of surviving cancer. It seems even Fido’s family has new tricks to teach.
Tragically, COVID-19 and ongoing war in the region have prevented Love and her collaborators from returning to the CEZ since. “Our priority is for people and collaborators there to be as safe as possible,” she says. Although Love’s work ethic is undeterred and results tantalizing, the real danger to friends and colleagues highlights that no research occurs in a vacuum, even when conducted in an area as isolated and abandoned as Chernobyl. Since the Russian invasion of Ukraine, the CEZ may have become even more dangerous as militants laid landmines in these already irradiated fields. It’s promising, dangerous work in an uncertain future.
Love will present this work at the Annual Meeting of Society of Integrative and Comparative Biology’s Annual Meeting in Seattle, Washington in January 2024.