The important portion of a targeted therapy for killing cells - cancer cells in this case - is not the part that destroys the cell itself. Any old chemotherapy drug can be used to that end. The point of the targeting mechanism is that the drug can be delivered in tiny, precise doses to minimize side-effects and any harm to surrounding tissues. These technologies are well worth watching because they will have far broader applications than just cancer. There are many areas in the aging body where targeted cell destruction will do a great deal of good, such as senescent cells and portions of the immune system. Here is an example from the cancer research community: "The process involved is akin to building and equipping a car with the finest features, adding a passenger (in this case the cancer drug), and sending it off to its destination (in this case the cancer cell). To design the 'vehicle,' researchers used a selection strategy developed by Farokhzad's team that allowed them to essentially select for ligands (molecules that bind to the cell surface) that could specifically target prostate cancer cells. The researchers then attached nanoparticles containing chemotherapy, in this case docetaxel, to these hand-picked ligands. To understand Farokhzad's selection strategy, one must understand ligand behavior. While most ligands mainly have the ability to bind to cells, the strategy of Farokhzad and his colleagues allowed them to select specific ligands that were not only able to bind to prostate cancer cells, but also possessed two other important features: 1) they were smart enough to distinguish between cancer and non-cancer cells and 2) they were designed to be swallowed by cancer cells. ... Most ligands are engulfed by cells, but not efficiently. We designed one that is intended to be engulfed."