Stanford researchers develop new molecular probe
Researchers at the Stanford University School of Medicine in Palo Alto, Calif., have developed a molecular probe that labels active proteases in cancer cells. The goal of the scientists is to use the probe to improve the diagnosis and treatment of cancer and other diseases, according to Stanford.

The probe carries a fluorescent tag that lights up when it binds to the protease. The tag beams out near-infrared light that passes through skin and is detectable with a special camera.

According to the article’s lead author, Galia Blum, PhD, a postdoctoral scholar in the laboratory of Matthew Bogyo, PhD, assistant professor of pathology, the detection of breast cancer is normally done by mammography, using x-rays — which could increase the risk of cancer. Blum said these probes may ultimately provide a less harmful, noninvasive method of detecting cancer.

Bogyo, Blum and colleagues designed the probe to bind to a subset of a family of proteases called cysteine cathepsins, which are more active in several types of cancer as well as other diseases. Now they are tinkering with the probe’s configuration in an effort to create a variant that recognizes the enzymes involved in apoptosis, the process of cell death. This could ultimately allow researchers and doctors to visualize response to chemotherapy in tumors, Bogyo said.

The use of the imaging technique in mice is described in a study published in the Sept. 9 advance online issue of Nature Chemical Biology.

The research was funded by grants from the U.S. National Institutes of Health, the U.S. Department of Defense, the Susan G. Komen Breast Cancer Foundation and the Deutsche Forschungsgemeinschaft.