Microscopy shows malfunctioning receptor in cancer cells

Ashley N. Rice, ashley.rice@photonics.com

A new microscopy method uses photon counting to study malfunctions in specific cancer cell proteins, which could lead to targeted treatments.

The technique is a significant improvement over studying cancer cell cultures with a traditional microscope, which cannot resolve objects as small as the protein clusters, according to researchers.

Using the new technique, University of Akron assistant professor of chemistry Dr. Adam Smith measured the sizes of clusters of epidermal growth factor receptor (EGFR) and observed how the clusters malfunction in cancer cells. EGFR is a protein abundant in lung and colon cancers, glioblastoma and others.

“We can directly observe protein clusters in a living cell membrane that are invisible to traditional methods. This opens up the possibility to directly measure the effect of drugs on the target proteins,” Smith said.

One problem with EGFR is its location within the cell membrane, Smith said, adding that the membrane “can be thought of as a fence line that defines the cell boundary, but in reality, it is more like an untamed hedgerow.”

Now he can study in real time how EGFR works in healthy cells and also how it malfunctions in cancer cells.

Subsequent research on the interaction of drugs with the targeted EGFR “will significantly improve drug discovery, which too often relies on indirect measure of efficacy,” Smith said.

His work lies at the heart of current-day cancer research, which focuses on developing targeted drugs to kill cancer cells without the collateral damage associated with traditional treatments like chemotherapy.

The work was published in Cell (doi: 10.1016/j.cell.2012.12.032). Partners in Smith’s research include scientists from the University of California, Berkeley, and Columbia University. The National Center Institute, Howard Hughes Medical Institute and the US Department of Energy provided funding for this research.