Washington, May 6 : A new study by researchers at the Cancer Research UK Cambridge Research Institute has discovered how specific changes in a gene called fibroblast growth factor receptor 2 (FGFR2) increase the risk of developing breast cancer.
The study authored by Kerstin Meyer and colleagues has explained how precise changes in the FGFR2 gene change the way regulatory molecules bind to it, and causes increased gene expression, leading to the increased risk of developing breast cancer.
The researchers compared all of the tiny differences in the genomes of people with breast cancer to those in a control population, and discovered that FGFR2 was found to be different between the two groups. FGFR2 encodes a protein located in the cell membrane and takes part in a signalling pathway important for cell growth.
In this study, researchers identified what exactly these slight genetic changes mean at the molecular level. FGFR2 genes altered at two specific points have a greater affinity for binding certain transcription factors, i.e. regulatory proteins that influence gene expression patterns.
This additional binding leads to the production of more FGFR2 protein in cells carrying the mutation and this would suffice for increasing the risk of cancer in a small but significant amount.
However, the mutation doe not occur in the coding regions of the genes (the bits translated into protein by cellular machinery), but rather, in an intron (a region of DNA found amongst the coding bits).
Therefore, these two alterations affect the regulation of the gene, but the proteins produced are normal. In fact, the mutation is too much for the cells to develop as normal, and thus they become cancerous.
The study is published this week in the open-access journal PLoS Biology.