How to track down tiny tumours
ONE problem with cancers is detecting them when they are small and easy to deal with. Once they have grown large enough to be noticed, they have often also spread to other tissues, with lethal consequences. However, Norman Maitland of the Yorkshire Cancer Research Laboratory, in Harrogate, England, thinks that he may have a solution to this difficulty.
Dr Maitland speculated that if he could attach glowing proteins to viruses programmed to find and infect cancer cells, he could make tumours easier to see. The proteins in question come from the crystal jelly, a marine organism. Their original extraction was rewarded with the Nobel prize for chemistry in 2008.
To use crystal-jelly proteins to illuminate tumours, Dr Maitland and his colleagues developed a series of viruses, ranging from a stripped-down version of HIV to an insect virus reprogrammed to infect human cells, that have been modified to attach specifically to proteins on the surface of the cancer cells in question. They have also been programmed to cause the production of crystal-jelly protein, by splicing a prostate-specific control sequence into their genetic material, next to a version of the fluorescent-protein gene.