A leading Yorkshire scientist is trying to develop new drugs by synthesising different forms of the special sugars found in cancer cells. Now, with support from the Association for International Cancer Research (AICR), Dr Robert Falconer will be using his discovery to search for new molecules to stop disease spread.

Dr Falconer, a Lecturer in Medicinal Chemistry based in the Institute of Cancer Therapeutics at the University of Bradford explains: "On the surface of cancer cells there is a long molecule, called polysialic acid, which is made up of about 200 identical simple sugars linked together.

"Polysialic acid has been found on the surface of a number of different human cancers. When these cancer cells start to spread, they appear to get more polysialic acid on their surface. We believe that this helps these cells 'unstick' from their neighbouring cells, so they can start invading the surrounding tissues and moving away from the original tumour.

"Our idea is quite simple. If we can stop these cancer cells making so much polysialic acid, they won't find it so easy to spread. Cancers that don't spread, or only spread slowly, are less dangerous and are easier to cure."

Dr Mark Matfield, AICR's scientific adviser says the surface of cells carries a complex mixture of proteins and sugars. "In the past, most scientific attention has been directed at the differences in the proteins but Dr Falconer is particularly interested in the differences in the sugars found on cancer cells.

"The long molecules of polysialic acid are built up by adding one simple sugar, called sialic acid, at a time to the growing molecule. Dr Falconer will use altered versions of the sialic acid molecule to block the enzymes that build these long polysialic acid molecules."

Dr Falconer has already made several variations of the normal sialic acid molecule. He will chemically synthesise many other different varieties of these unnatural sugars and, with colleagues at the Institute, will test their ability to block the enzymes that build polysialic acid.

Initially, these tests will be carried out using purified versions of these enzymes. Those molecules that are found to block polysialic acid synthesis will then be tested directly on cancer cells growing in the laboratory, to make sure that they have the same effect on the cells. The final stage of the project will be to find out if these molecules, which stop cancer cells making polysialic acid, also stop the cells moving and spreading.

Derek Napier, AICR Chief Executive, says the charity has awarded a three-year research grant of �142,000 to Dr Falconer, which should enable him to identify a number of molecules that block cancer cell spreading. "This is an exciting project and is given in line with AICR's policy of funding the most novel approaches to research worldwide.

"However, there will need to be further analyses and testing -- taking several more years - before it is known whether these molecules will make effective drugs to help treat cancer."