"If we could figure out how to make this work [in humans], it would open up a whole new class of targets that hadn't been available," says Hahn, who is also director of the Center for Cancer Genome Discovery at Dana-Farber and a senior associate member of the Broad Institute.
Lead authors of the paper are Yin Ren, an MD/PhD student in Bhatia's lab, and Hiu Wing Cheung, a postdoc in Hahn's lab.
An abundance of targets
Through Project Achilles, Hahn and his colleagues have been testing the functions of many of the genes disrupted in ovarian cancer cells. By revealing genes critical to cancer-cell survival, this approach has narrowed the list of potential targets to several dozen.
Typically, the next step in identifying a good drug target would be to genetically engineer a strain of mice that are missing (or overexpressing) the gene in question, to see how they respond when tumors develop. However, this normally takes two to four years. A much faster way to study these genes would be simply to turn them off after a tumor appears.
RNA interference (RNAi) offers a promising way to do that. During this naturally occurring phenomenon, short strands of RNA bind to the messenger RNA (mRNA) that delivers protein-building instructions from the cell's nucleus to the rest of the cell. Once bound, the mRNA molecules are destroyed and their corresponding proteins never get made.
Scientists have been pursuing RNAi as a cancer treatment since its discovery in the late 1990s, but have had trouble finding a way to safely and effectively target tumors with this therapy. Of particular difficulty was finding a way to get RNA to penetrate tumors.
Bhatia's lab, which has been working on RNAi delivery for several years, joined forces with Hahn's group to identify and test new drug targets. Their
|Contact: Sarah McDonnell|
Massachusetts Institute of Technology