The search for biomarkers of disease in spit
Source: University of Minnesota It's a researcher's dream: a simple, noninvasive test to detect life-threatening cancer, heart disease, or other maladies while they're still treatable. A team of University of Minnesota researchers is in hot pursuit of that goal, using one of the simplest means imaginable: testing spit. They've discovered that conditions such as breast and oral cancer leak certain proteins into saliva, and if detected, such proteins can be "biomarkers" for the disease. "This would be an easy way to monitor oral cancer," says Timothy Griffin, an associate professor of biochemistry, molecular biology and biophysics. "Every year in the United States there are about 40,000 cases, more than cervical or ovarian cancer, melanoma, or lymphoma, and it has a higher mortality." Saliva contains at least 2,000 proteins, but the most abundant ones tend to be the least informative, he notes. But he and his colleagues have become the world experts on snagging rare proteins from spit and detecting both their presence and their abundance. Promising discoveries In a study of 10 women with metastatic breast cancer, the researchers sifted through their salivary proteins and found a handful that were already known to seep into the blood of women with this cancer. The proteins appeared only at very low levels in saliva of healthy controls. "The next idea is, can you take this back through the earlier stages to detect nonmetastatic cancer?" says Griffin. Biomarker proteins also appear in saliva of patients with oral cancer. Team members Frank Ondrey, an [...]