Scientists at The Wistar Institute and their colleagues have identified, for the first time, a molecule that can regulate microRNAs short strands of RNA that play a vital role in gene expression and are closely associated with cancer. The discovery points the way to the development of a new generation of cancer drugs.
The research team identified a small molecule that blocks the pathway of a particular miRNA, called miR-21, that is implicated in brain cancer, as well as lung, colon, breast, and ovarian cancer. With further development, the molecule has the potential to boost patient response to existing chemotherapies, as well as to become a stand-alone cancer drug, says Wistar's Qihong Huang, M.D., Ph.D., co-senior author of the study.
Although miRNAs were discovered less than two decades ago, their importance in regulating human development and disease is already clear. While the human genome is thought to contain 800 to 1,000 miRNAs, only a few hundred have been described.
Thus, miRNAs represent a largely unexplored class of targets for the development of therapeutics and diagnostics, says Huang, an assistant professor in Wistar's Molecular and Cellular Oncogenesis Program.
"This is a totally novel target," he says. "It's very understudied, and still in its infancy, but its potential is tremendous. Because miRNAs have the ability to shut down genes and prevent their expression, they may ultimately provide a target for therapies that are more selective than conventional chemotherapy drugs and have fewer side effects."
Alexander Deiters, Ph.D., of North Carolina State University, co-directed the study.
In regulating the molecular mechanisms behind gene expression, miRNAs can control the way in which whole chromosomes, or regions of chromosomes, are activated or deactivated. They are thought to directly regulate the expression of at least 30 percent of all human protein-encoding genes.
|Contact: Abbey J. Porter|
The Wistar Institute