Genes are one thing, but SIUC scientist Luke Tolley says proteins are where the rubber meets the road in the fight against cancer.

Far more complex than their biological counterparts, proteins do the work assigned to them by DNA, such as telling a cell when and how to reproduce itself. For this reason, many researchers believe protein malfunctions may be at the root of cancer, which involves abnormal cell growth.

Scientists would like to be able to separate and identify all of the proteins present in cells and to compare the protein makeup of healthy versus abnormal cells. But that's a tall order. A typical cell in the human body, for instance, can contain as many as half a million proteins, some in high concentrations and some in extremely low concentrations. Furthermore, the protein content of a cell fluctuates depending on body processes (such as metabolism).

Luke Tolley, assistant professor of chemistry, and Cal Meyers, distinguished professor emeritus of chemistry, recently won a two-year, $248,000 grant from the National Cancer Institute to develop a new and improved instrument for separating and identifying proteins in complex mixtures like cell solutions.

The goal is to get a much more complete picture of the protein profiles of cells. "This is a new tool you can use to look at things you haven't been able to look at before," Tolley says.

Tolley's technology is called "dynamic isoelectric focusing" of protein molecules. With seed money provided by the University in 2005, he built a working prototype of the device. With the NCI funding, he and his doctoral students are now working on an improved prototype.

"The [new] device does better separation [of proteins] much faster, with results that are more reproducible," Tolley says. Simply being able to run more separations faster—his device takes only about 30 minutes to run a separation—will allow scientists to do more valuable research.

The new device is relatively inexpensive and easy to fabricate, adding to its appeal. If its further development is successful, it could become standard equipment in research labs.

Healthy and cancerous cells differ in their protein profiles. For example, cancer cells tend to contain more types of proteins, some of which have undergone modifications. If a given protein is absent in healthy cells but found in cancerous cells, it could be either a cause or a byproduct of that cancerous state.

Scientists need to determine which is the case. Tolley's device will allow specific proteins to be extracted from cancer cells and introduced into healthy cells so that their effects can be studied.

The instrument uses tiny, incremental differences in voltages to isolate proteins in samples held in glass tubes no thicker than a human hair. So far, Tolley has succeeded in isolating about 1,100 proteins from a mix. Ultimately he will couple the device to one or more existing technologies to boost the number of proteins that can be isolated potentially into the millions—and do it far more reliably than is now possible.

As proof of concept for the NCI grant, Meyers, who has developed some unusual anti-cancer compounds, will use the instrument to analyze prostate cancer cell proteins before and after exposure to those compounds, looking for key differences that might lead to improved treatments.

"The goal is to figure out what those [protein] differences mean to cancer research," Tolley says. "That's the next step."