Oncology: A medical matryoshka doll

TRIPLE-NEGATIVE breast cancer is one of the nastiest there is. It is hard to treat and almost always fatal. One reason treatments tend to fail is that its cells are armed with molecular pumps which remove anti-cancer drugs that manage to get inside them. But Paula Hammond, a chemical engineer at the Massachusetts Institute of Technology, thinks she can deal with this defence using triple-layered chemical bombs a few billionths of a metre across. The layers, somewhat reminiscent of a Russian matr...