PATIENTS with bowel cancer could soon be targeted for treatment with aspirin after new research revealed how the household painkiller blocks tumour growth.

It has long been known that taking aspirin regularly can help to stave off bowel cancer, but it was unclear why the drug had this effect.

Now cancer researchers at Edinburgh University have shown that the painkiller blocks a key process linked to tumour formation.

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The findings, published today in the journal Nucleic Acid Research, were said to offer "great significance" to cancer research, with "far reaching implications for understanding of the anti-tumour effects of this agent".

Dr Lesley Stark, a co-author of the study based at the Cancer Research UK Edinburgh Centre, said: “We are really excited by these findings as they suggest a mechanism by which aspirin may act to prevent multiple diseases."

The team tested the effects of aspirin on cancer cells grown in the lab and on tumour biopsies removed from colon cancer patients.

They discovered that aspirin blocks a key protein called TIF-IA, which is essential for a structure known as the nucleolus to function.

The nucelolus, a dense spherical structure, is found in the nucleus of cells.

When this structure is activated, it is known to drive tumour formation and dysfunction has also been linked to degenerative diseases such as Alzheimer’s and Parkinson’s, as well as ischaemic heart disease.

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Stopping it in its tracks is therefore seen as a key tool to preventing cancer, as well as other illnesses.

Not all colon cancer patients respond to aspirin but the researchers say their findings could help pinpoint those most likely to benefit, based on the genetic make-up of their tumours.

It could also provide the blueprint to develop alternative drugs that can mimic the benefits of aspirin for cancer patients without the potential harmful side effects, such as internal bleeding and an increased risk of certain types of stroke.

Dr Stark said: "There's a couple of ways that this information could be used to help patients.

"One of those is to take what we've learned to understand the nucleolus more because the structure has been known to be involved in a number of diseases but actually it's not that well researched. So this could offer us insight into the mechanisms of disease.

"It's also a way to find suitable patients. You can't give aspirin to all cancer patients, or even all patients, because of its side effects, so if you can identify people who would benefit from taking aspirin by identifying biomarkers of response then obviously we can help to target the drug to the right people.

"I think that's something we could act on relatively quickly - that could be quite a short-term goal because we're already working with people who are doing trials of aspirin."

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It comes as the latest bowel screening statistics for Scotland, published last week, show that two-thirds of Scotland’s 14 health boards were in breach of the national waiting time standard on bowel cancer tests, with nearly 4000 patients waiting longer than six weeks for a colonoscopy in the first quarter of 2018.

Nearly 1,200 patients were waiting longer than six weeks for an appointment for flexi-sigmoidoscopy, which checks for ulcers, polyps or cancer in the colon.

Demand for the tests has been increasing, largely due to the ageing population but more recently due to the introduction in Scotland of a simpler and more accurate home screening test which has boosted the number of people taking part in screening.