Sam Kleeman

Title: Application of a miRNA signature to the non-invasive diagnosis of Barrett’s oesophagus

Summary: During my third year at the University of Cambridge, I was fortunate to be able to undertake a cancer screening project at the MRC Cancer Unit, Cambridge. For several years, I have taken a keen interest in better understanding how cancers develop and how we can better treat them. Cancer of the oesophagus has a very poor prognosis with less than 1 in 5 of the 9000 patients diagnosed every year surviving 5 years. The most common type of oesophageal cancer, known as oesophageal adenocarcinoma, is always preceded by a precursor stage known as Barrett’s oesophagus (BE) where the cells lining the oesophagus become more like the cells lining the intestine. Once diagnosed, treatments exist that can destroy the abnormal cells to prevent them developing into cancer.

Currently, only a small proportion of people with BE know they have the condition – there is a need to develop simple diagnostic tests that can be used to screen people for BE. Therefore, the aim of my project was to see whether measuring a type of small nucleic acid known as micro RNA (miRNA) could determine whether a given tissue sample contained BE or not. Rather than using tissue samples collected by endoscopy, we used samples collected by swallowing a pill-on-a-string known as the ‘Cytosponge’. We found three miRNAs that were highly expressed in BE but not normal tissue samples – these can be used to accurately diagnose BE in patients who have swallowed the ‘Cytosponge’. As a result, this test could be used as the basis of a novel screening programme in which patients at high risk of BE (for example, male patients with reflux) could swallow the ‘Cytosponge’ at their GP to find out whether they have the disease. By diagnosing more cases of BE, more patients could be referred to receive treatment and so fewer patients would ever progress to oesophageal cancer.