New research uses nanosensors to detect protein-to-protein interactions that may signal cancer. The findings may prove especially useful for identifying lymphocytic leukemia much earlier on.

Cancer is one of the leading causes of death both in the US and worldwide. According to the National Cancer Institute, there were more than 8 million cancer-related deaths across the world in 2012, and over 600,000 people in the U.S. may die from the disease in 2018.

Early detection of this life-threatening illness is crucial, and medical scientists are hard at work devising newer and more effective ways of diagnosing cancer as soon as possible.

Now, new research uses tiny sensors to detect minute molecular changes that may be indicative of cancer.

Liviu Movileanu, a professor of physics at the College of Arts and Sciences at Syracuse University in New York, together with Avinash Kumar Thakur, a doctoral researcher in physics at Syracuse, detail the role of these nanosensors in a paper appearing in the journal Nature Biotechnology.

As Prof. Movileanu explains, the nanosensors may be particularly helpful for detecting lymphocytic leukemia, a form of cancer that starts in the bone marrow and spreads into the blood.

In the U.S., almost 21,000 new cases of lymphocytic leukemia are likely to occur in 2018, and more than 4,500 people may die as a result.

How the nanosensors work

The nanosensors originating in Prof. Movileanu's laboratory can detect so-called protein-to-protein interactions (PPIs), that is, processes that are essential for the development of cells.

The so-called interactome refers to the "complete map of protein interactions that can occur in a living organism." Interactomics—or mapping the interactome, using cutting-edge technological and computational techniques—is a flourishing subfield of biophysics that studies the consequences of these interactions.

PPIs depend on a variety of factors, such as the type of cell, its developmental stage, and environmental conditions. Some PPIs are stable, but others are transient.

For instance, the interactions needed to activate gene expression or those that affect cell signaling and the development of cancer cells are transient, meaning that they last only about a millisecond.

The fleeting nature of these PPIs makes them difficult to detect with the methods that are currently available.

However, the nanosensors originating from Prof. Movileanu's lab bypass this obstacle by creating a small opening in the cell membrane through which electric current passes.

When proteins pass through these small openings or nanopores, they change the intensity of the electric current. These changes reveal the identity and properties of each protein.

"The data gleaned from a single protein sample is immense," says Prof. Movileanu, who earned his PhD in experimental physics from the University of Bucharest in Romania and is currently a member of the biophysics and biomaterials research group in the Department of Physics at Syracuse.

"Our nanostructures allow us to observe biochemical events in a sensitive, specific, and quantitative manner," the researcher goes on. "Afterward, we can make a solid assessment about a single protein sample."

"Detailed knowledge of the human genome has opened up a new frontier for the identification of many functional proteins involved in brief physical associations with other proteins," the researcher continues.

"Major perturbations in the strength of these PPIs lead to disease conditions. Because of the transient nature of these interactions, new methods are needed to assess them."

The physicist also explains how the finely-tuned detection mechanisms of his nanosensors can help fight cancer.

"If we know how individual parts of a cell function, we can figure out why a cell deviates from normal functionality toward a tumor-like state [...] Our little sensors may do big things for biomarker screening, protein profiling, and the large-scale study of proteins [known as proteomics]."

—Prof. Liviu Movileanu

Prof. Movileanu hopes that his nanosensors will be particularly useful for detecting lymphocytic leukemia, a condition where the blood cells do not mature and die as normal, but "build up in the bone marrow and crowd out normal, healthy cells."