SCIENTISTS have used cutting-edge microscopes [...].

SCIENTISTS have used cutting-edge microscopes to look at the effect of chemical signals on cancer cells which could hold the key to stopping secondary forms of the disease.

A team from Cancer Research and Breast Cancer Campaign examined a chemical in the body called transforming growth factor beta (TGF) and what it did to breast cancer cells.

The substance activates genes which cause the cancer cells to move from the breast into another part of the body. Once they are there, the "signal" from the TGF stops and this means the cells start growing in the new site, according to the research published in Nature Cell Biology. Lead author of the study, Dr Erik Sahai, said: "We have used cutting-edge filming techniques to study the behaviour of cancer cells. "The results helped us to find the set of genes that are behind the spread of breast cancer - and that the genes need to be first turned on and then off in order for single cancer cells to be able to relocate.

"Surprisingly little is known about the way cancer cells spread through the body because it is so incredibly difficult to study.

"In a medium-sized tumour there could be a billion cells - and only a small proportion might break away and spread. "So it is like trying to find - and understand - a moving needle in a very big haystack." Breast cancer is the second most fatal form of the disease for UK women after lung cancer.