Ants can learn to sniff out human cancer cells, as dogs already do, but even more quickly, according to a scientific study that sets out to explore this idea.
Several experiments have recently shown that canine sense of smell can detect some cancerous tumors that emit volatile organic compounds (VOCs), which a human cannot perceive.
But this method requires extensive training — between six months and a year per dog — and is expensive, on the order of tens of thousands of dollars, Baptiste Piqueret, lead author of the study published this week in the journal iScience, told AFP.
This ethologist at the Sorbonne Paris Nord University tried the experiment with ants, an insect that uses its powerful sense of smell for its daily tasks and learns quickly.
The scientist, supported by a team of French institutions such as the Institut Curie, chose the most common species of ant in the northern hemisphere, the Formica Beetle.
The insects were submitted to laboratory learning protocols, in which they associated an odor with a reward (a drop of sugar water).
In a first training session, the ant “walked freely until it found a drop of sugar water. While drinking, it sniffed the environment (with its antennae) impregnated with a particular odor”, explained the researcher.
In the next step, the insect had the option of going to a place with the smell it had learned and to another with a different smell, this time without a drop of sugar water.
“If the ant had learned correctly, it would have spent much more time prowling around the odor associated with sugar water, looking for the reward,” he said.
These tests were carried out with odors from healthy human cells and cancer cells (produced by ovarian cancer) to see if the ants learned to tell them apart. And then with two diseased (breast cancer) cells to see if the insects differentiated between two cancer subtypes.
“Three training sessions of less than an hour were enough for them to learn” the difference between these two subtypes, assured the researcher.
The protocol is very simple, and the training was done at home, during the confinement that France suffered during the spring of 2020, explained the researcher.
Now it is necessary to analyze “the effectiveness of this method thanks to clinical tests with a complete human organism”, said a statement from the French research organization that supported the experiment (CNRS).
Preliminary experiments are being carried out with the urine of mice suffering from cancer.
