NCRI Cancer Conference 2009: Profiling pancreatic cancer

Could microRNAs be the key to detecting pancreatic cancer?

We’ve blogged here before about how difficult it is to detect and treat pancreatic cancer, and that one of the main challenges is that the disease is often diagnosed at a late stage. So it was encouraging to hear from Dr Jörg Hoheisel about his search for biomarkers that could potentially be used to detect pancreatic cancer earlier

Hoheisel, who spent five years at Cancer Research UK’s London Research Institute, is now Head of the Division of Functional Genomics at the German Cancer Research Centre in Heidelberg. He’s been working on understanding pancreatic cancer for 20 years. And thanks to new technology and collaborations with hospitals across Europe giving him access to crucial samples, he’s now able to drill down in much more detail.

His team is systematically studying thousands of pancreatic tumour samples and normal pancreatic tissue, as well as blood and urine from patients and healthy volunteers, looking for molecules that could indicate the presence of cancer. It’s like looking for a needle in a haystack, and it’s only possible because new techniques allow the team to study thousands of samples at the same time.

One thing they’re particularly interested in is the level of different microRNAs – tiny molecules that help to control the activity levels of genes (for more background see this previous post). So far Hoheisel and his team have built up a profile of microRNA activity in 250 cancer samples, which has highlighted two possible pathways that could lead from a healthy pancreas to pancreatic cancer, possibly via pancreatitis (inflammation of the pancreas, a known risk factor for the disease).

They’re also studying differences in the way cells switch off their genes using a process called methylation – adding molecular ‘bookmarks’ to certain genes that mark them as being turned off. In pancreatic cancer, it seems that between 75 and 85 per cent of genes are turned off in this way in the late stages of disease, compared with a much smaller amount (~5-10 per cent) in the early stages.

But as promising as it sounds, it’s very early days for this research. The researchers will need to analyse many more samples to confirm that these differences between healthy and cancer cells are real and that they can be detected accurately and sensitively. Even so, Dr Hoheisel hopes that these findings could form the basis of a diagnostic test for pancreatic cancer in the future.

And in terms of understanding the disease and finding urgently-needed new treatments, it will open up vital new avenues to explore.

Joanna Owens, Science Information Manager