Teardrops Could Enable Early Detection of Cancer

Teardrops need not be futile anymore; they could, in fact, aid in detecting chronic diseases such as cancer.

In a breakthrough study, University of California (UC) Irvine scientists have established the existence of a disease-fighting protein in human teardrops. Using a novel technique, scientists have managed to isolate and study proteins in human tears that could go a long way in early detection of cancers and other chronic diseases.

In the findings published in the Jan. 20 issue of the journal Science, scientists isolated mechanisms of the teardrop protein - lysozymes - and their ability to destroy harmful bacteria.

The study could potentiate the ability to detect diseases at the molecular level, thereby saving lives. The technology is poised to help study complex molecules but could also have broader applications in medicine.

Researchers decoded the protein's behavior by building one of the world's smallest transistors, about 25 times smaller than the circuitry found in laptop computers or smartphones. Individual lysozymes were glued to the live wire and their eating activities were monitored.

This led scientists to understand the exact mechanism by which lysozymes destroy dangerous bacteria.

It has long been known that human tears contain antiseptic proteins called lysozymes but scientists were clueless as to how these proteins eliminate larger bacteria within the tear gland.

In the new study, the UC scientists found that lysozymes have jaws that latch on and chomp through rows of cell walls like someone hungrily devouring an ear of corn, observed the study authors.

Those jaws chew apart the walls of the bacteria that are trying to get into your eyes and infect them, said Gregory Weiss, who co-led the project with associate professor of Physics & Astronomy Philip Collins. A key element is that we're using carbon nanotubes, which are already the world's smallest wires, Collins said. It looks very much like a circuit board, shrunken down like a million times.

The scientists observed the data flow from the tiny transistor on a computer screen. The researchers explained that the sound of the chomping molecular jaws would be made audible if hooked up to speakers. Our circuits are molecule-sized microphones, Collins said. It's just like a stethoscope listening to your heart, except we're listening to a single molecule of protein.

The study noted that it took years for the UCI scientists to assemble the transistor and attach single-molecule teardrop proteins. The scientists hope the same novel technology can be used to detect cancerous molecules.

According to Weiss, It could take a decade to figure out but would be well worth it. If we can detect single molecules associated with cancer, then that means we'd be able to detect it very, very early, Weiss said. That would be very exciting, because we know that if we treat cancer early, it will be much more successful, patients will be cured much faster, and costs will be much less, he added.