Media

• Publications
• Latest News

Understanding why cancer spreads

UCD Conway Institute researchers Professor Liam Gallagher and William Faller have been part of an international team working to understand the processes behind the development of metastases in cancer patients. The findings were published in the September issue of Proceedings of the National Academy of Sciences (PNAS).

The research has centred on MicroRNAs (miRNAs) which are small non-coded strands of RNA (ribonucleic acid). Broadly speaking, miRNAs are involved in influencing which genes are ‘expressed’ or ‘switched on’, and therefore which characteristics appear in the organism. As a result, miRNAs are key in understanding physiological processes, and the disruption of these processes in situations of disease or illness.

The research team - based in Spain, Texas, Ohio, the UK and UCD - have discovered that a specific series of miRNAs can influence whether a tumour progresses or is inhibited, depending on whether they are switched on or silenced. These miRNAs normally carry tumour suppressors, and so, when they are silenced tumours are able to grow and spread. Where the relevant miRNAs were reintroduced or ‘reawoken’ in a cancer cell, tumour growth was found to be reduced and the progression of metastasis was halted.

So what decides whether the miRNAs are silenced or not? The research team, which is led by Dr. Manel Esteller, has discovered that a process known as DNA methylation is involved in the silencing of those miRNAs that carry tumour suppressors. This aberrant DNA methylation is therefore also implicated in the development of metastases, or ‘secondaries’. The researchers have been able to tell which particular miRNAs are most involved in this process, and also which methylation signatures indicate metastasis. This is of benefit in predicting how, or whether, a patient’s cancer will progress, but will also provide a molecular basis for developing targeted drug therapies for patients with metastasis.