Genes Linked To Breast Cancer Survival

They are currently testing activity of two genes that could pick out those women who are at an increased risk of dying from their breast cancers, according to a new study of almost 2,000 patients.  The tumors in women that had a specific pattern of activity in the two genes were 3 times as likely to die within 10 years as others with a different pattern of activity.  The Institute of Cancer Research scientists in London spotted the pattern of gene activity of these cells, with a particular ability to escape from the glue that normally holds them in place.  According to the scientists, these genes could play a key role in releasing cells from this extracellular matrix so they can spread around the body.

This research is funded by The Institute of Cancer Research and Breast Cancer Now, and could be used to develop tests for aggressive breast cancers, or to even identify other new targets for cancer treatment.  This study was published in the journal Oncotarget, which looked at breast cancer cells that were positive for the protein HER2, the target for the drug Herceptin, which is found in around 20% of tumors.  

The Institute researchers have developed a new image-based screening technique in order to identify cancer cells that didn’t stick to the protein laminin, which helps build scaffolding around cells that glue them together.  These cells have been found to have high activity in a gene called F-12 and low activity in another one called STC2.  The same genes were analyzed by the researchers among 1,964 breast cancers, and found that this pattern of activity was strongly linked to survival.

The tumors in women that had high F12 activity and low STC2 activity had a 32% chance of dying within 10 years.  Those with low F12 and high STC2 activity had only a 10% chance of dying.

Further research is needed to establish how these genes could interfere with the extracellular matrix and help cancer cells grow and spread.  Dr. Paul Huang, study leader and leader of the Protein Networks Team at The Institute of Cancer Research in London, said that the survival rates for breast cancer are much higher than from a few decades ago, but the disease remains deadly once it has spread around the body.  The study shows how cancer cells unstick themselves from healthy tissue and could help select the women at high risk of their cancer spreading and becoming fatal.

If these results are confirmed in larger studies, it might give us a new way of assessing women’s survival chances in the clinic, and adjusting treatment accordingly.

According to Professor Paul Workman, Chief Executive of ICR, they have seen strides in the treatment of breast cancer, but once it begins to spread around the body it is still often fatal.  Hopefully this new study will help us understand some of the processes that control how breast cancers spread, and identify a pattern of genetic activity that could be used to pick out these women who are particularly at risk.

-Dr Fredda Branyon