Ants can detect the scent of cancer in urine

Ants can be trained to detect cancer in urine, a new study finds.

Although ant sniffing is a long way from being used as a diagnostic tool in humans, the results are encouraging, the researchers said.

Because ants lack noses, they use olfactory receptors on their antennae to help them find food or sniff out potential mates. For the study, published Jan. 25 in the journal Proceedings of the Royal Society B: Biological Sciences (opens in new tab), scientists trained nearly three dozen silky ants (Formica fusca) to use these acute olfactory receptors for a different task: finding tumors.

In a lab, scientists grafted slices of breast cancer tumors from human samples onto mice and taught the 35 insects to "associate urine from the tumor-bearing rodents with sugar," according to The Washington Post (opens in new tab). Once placed in a petri dish, the ants spent 20% more time next to urine samples containing cancerous tumors versus healthy urine, according to the study.

"They just want to eat sugar," Baptiste Piqueret (opens in new tab), the study's lead author and an ethologist at Sorbonne Paris North University in France, told The Washington Post.

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Because tumor cells contain volatile organic compounds (VOCs) that researchers can use as cancer biomarkers, animals such as dogs — and now ants — can be quickly trained to detect these anomalies through their sense of smell. However, researchers think that ants "may have the edge over dogs and other animals that are [more] time-consuming to train," according to The Washington Post. 

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This is important because the earlier cancer is detected, the sooner treatment can begin. The researchers are hopeful that cancer-sniffing ants have the potential "to act as efficient and inexpensive cancer bio-detectors," they wrote in their study. 

"The results are very promising," Piqueret said. However, he cautioned that "it's important to know that we are far from using them as a daily way to detect cancer."