Researchers create trillions of different varieties of aptamers in a solution. They then immerse cells known to carry the sought-after disease in the solution. After an incubation period, they rinse the cells.
The vast majority of the aptamers wash away, but those with stronger molecular affinity for the diseased cells remain. The researchers repeat the process several times, eventually shrinking the pool of aptamers to as few as 10 to 25 very strongly attached aptamers those most closely associated with the diseased cells. Analysis then reveals these aptamers molecular structure, as well as the molecular structure of the cells biomarkers they bind to.
As long as the molecules in question are expressed in a substantially different way on diseased and normal cells, they can be identified, Tan said.
Rebecca Sutphen, associate professor and director of the Genetic Counseling & Testing Service at the H. Lee Moffitt Cancer Center & Research Institute in Tampa, said improved diagnosis may not be the only application of the research.
The opportunity to identify cancer cell-specific biomarkers and potentially detect small numbers of cancer cells has many potential clinical applications, including disease detection, better imaging of tumors and even potential application for stem cells, she said.
Other biomarkers have been found for leukemia, but none is particularly reliable, Tan said. Tan and his colleagues reported using aptamers to recognize cancer cells in a 2006 paper in the Proceedings of the National Academy of Sciences. Tan said the latest paper advances that work by revealing the target biomarkers the selected aptamers recognize, Tan said. These targets will form a molecular foundation in understanding diseases, he said.
In 2006, we did not know what the aptamer recognized on the cancer cell surface, he said. In this current work, we report discovering these
|Contact: Weihong Tan|
University of Florida