RNA interference, a gene-silencing phenomenon discovered in the late 1990s, was hailed for its potential as a treatment in cancer and other diseases. But finding a way to deliver short stretches of RNA to tumors safely and effectively has been challenging. By themselves, small interfering RNAs (siRNAs) break down quickly and invade tumors poorly, so they need a delivery vehicle.
Now one exciting technology is enabling another. Scientists have successfully targeted cancer cells in mice by creating tumor-penetrating nanoparticles to carry siRNAs as their cargo.