(NaturalNews) Fruit flies are able to smell the difference between cancerous and healthy cells, and they can even tell the difference between different strains of cancer, according to a study conducted by researchers from the University of Konstanz in Germany and the University La Sapienza in Italy and published in the journal Scientific Report.
Animals that sniff out cancer
Because there are fundamental chemical differences between cancerous and healthy cells, the sensitive noses of many animal species are able to detect these differences - potentially making it possible to diagnose cancer significantly sooner than it could be detected by modern screening methods.
For example, a 2011 study found that dogs were able to detect the presence of lung cancer simply by sniffing the breath of patients. Notably, the dogs were able to correctly identify cancer even among patients who had recently smoked or who also suffered from chronic obstructive pulmonary disease. Current lung cancer screening tests are not able to do this.
In 2013, a Portuguese researcher successfully trained bees to do a "waggle dance" when they were exposed to air exhaled by patients suffering from specific diseases including cancer, tuberculosis and diabetes. She said that it takes only 10 minutes to train bees to do the dance in response to a specific disease. She simply exposes the bees to the odor that she wants them to fixate on, then immediately feeds them sugar. The bees learn to associate the smell with a reward.
In the most recent study, researchers took advantage of the fact that individual odor molecules physically attach to different combinations of nerve cells (neurons) on the antennae of fruit flies.
The researchers genetically engineered fruit flies so that their neurons would fluoresce under a microscope when activated by odor molecules. They then collected samples of the air found above lab samples of healthy human breast tissue and five separate strains of breast cancer cells.
The researchers then wafted each air sample across the antennae of fruit flies while examining the insects through a microscope. They found that each individual strain of breast cells activated a unique pattern among the flies' neurons, indicating the presence of unique combinations of volatile organic compounds.
In essence, the flies were able to "smell" the difference not just between healthy cells and cancerous ones but between each and every cancer strain.
Most sensitive test yet
The neuron imaging technique represents a breakthrough, because it gives much more precise information than an animal such as a dog would be capable of conveying.
"As not only cancer cells can be distinguished from healthy cells, but also subgroups were discernible within the cancer cells, it seems that even different types of breast cancer cells can be differentiated via the antenna of Drosophila," researcher Alja Ludke said.
Lead researcher Giovanni Galizia noted that the fruit flies are capable of detecting subtle differences that are invisible to many modern diagnostic techniques.
"What really is new and spectacular about this result is the combination of objective, specific and quantifiable laboratory results and the extremely high sensitivity of a living being that cannot be matched by electronic noses or gas chromatography," Galizia said.
Although many technical hurdles still need to be overcome, the researchers hope that their findings can lead to new tests to detect cancers earlier than ever.
"The high sensitivity of the natural olfactory receptors, paired with the quickness with which we can generate these test results, might lead to the development of a cheap, fast and highly-efficient pre-screening that can detect cancer cells well before we can discover them with the present diagnostic imaging techniques," Galizia said.