Scientists have developed a sensor system to "smell" different cancer types in the same way our noses identify and remember different odours.
Researchers at the University of Massachusetts Amherst have developed a rapid, sensitive way to detect microscopic levels of many different metastatic cell types in living tissue.
Study leader Vincent Rotello explained in a statement: "With this tool, we can now actually detect and identify metastasized tumor cells in living animal tissue rapidly and effectively using the 'nose' strategy.
"We were the first group to use this approach in cells, which is relatively straightforward. Now we've done it in tissues and organs, which are very much more complex. With this advance, we're much closer to the promise of a general diagnostic test."
In the fight against cancer, knowing the enemy's exact identity is crucial for diagnosis and treatment, especially in metastatic cancers (those that spread between organs and tissues).
For this work, the researchers took healthy tissue and mouse tumor samples and trained a nanoparticle-GFP sensor array to recognise them and the GFP to fluoresce in the presence of metastatic tissue.
"We can tune or teach our nanoparticle array to recognize many healthy tissues, so it can immediately recognise something that's even a little bit 'off,' that is, very subtly different from normal. It's like a 'check engine' light, and assigns a different pattern to each 'wrong' tissue. The sensitivity is exquisite, and very powerful."
Metastases are differentiated from healthy tissue in a matter of minutes, providing a rapid and very general means of detecting and identifying cancer and potentially other diseases using minimally invasive microbiopsies.
"It's sensitive to really subtle differences," continues Rotello. "Even though two cheeses may look the same, our noses can tell a nicely ripe one from a cheese that's a few days past tasting good.
"In the same way, once we train the sensor array we can identify whether a tissue sample is healthy or not and what kind of cancer it is with very high accuracy. The sensitivity is impressive from a sample of only about 2,000 cells, a microbiopsy that's less invasive for patients."
Findings appear in the current issue of the journal ACS Nano.