How aspirin helps to fight bowel cancer has been discovered by British scientists.
Experiments on tumours taken from patients found the painkiller blocks the ‘power station’ that fuels the disease.
Known as the ‘nucleosus’, it lies at the heart of cells – within the nucleus that contains the DNA.
Activation is known to drive tumour formation – and dysfunction has also been linked to Alzheimer’s and Parkinson’s diseases.
Experiments on tumours taken from patients found the painkiller blocks the ‘power station’ that fuels the disease
Hope for newer treatments
Around 41,300 people are diagnosed with bowel cancer each year making it the fourth most common cancer in the UK.
The breakthrough by Edinburgh University researchers could lead to new treatments for a host of conditions based on aspirin.
The drug can cause internal bleeding and certain types of stroke. Long term use is not advised.
The team say the study paves the way for the development of safer therapies that mimic aspirin’s effects.
Dr Lesley Stark, of the Cancer Research UK Edinburgh Centre, said: ‘The nucleolus is a highly dynamic, sub-nuclear organelle.’
She said its main function is being the hub of protein factories but it also acts as a critical stress sensor and coordinates the body’s response.
Dr Stark said: ‘We are really excited by these findings as they suggest a mechanism by which aspirin may act to prevent multiple diseases.’
Blocking tumour growth
Aspirin has anti-inflammatory properties and is recommended to reduce heart attack risk.
Previous studies have revealed if it is taken over a long period of time it can protect against several kinds of cancer including those of the bowel, breast, lung, prostate gland and stomach.
Scientists are increasingly turning to aspirin in the battle against cancer.. The theory was it hinders platelets – cells that help the blood to clot – from protecting tumours.
To investigate the possible mechanisms further, Dr Stark and colleagues looked at the action of the drug on bowel tumour growth.
They found the painkiller blocks a key process linked to tumour formation. Regular use is known to reduce the risk of colon cancer but the reason has not been well understood.
The researchers focused on the nucleolus – testing the effects of aspirin on cells grown in the lab and on tumour biopsies removed from bowel cancer patients.
They found the drug blocks a chemical called TIF-IA – a key molecule which is essential for the structure to function.
Not all bowel cancer patients respond to aspirin. The study could help pinpoint those most likely to benefit.
The future of treatment
Dr Stark said: ‘A better understanding of how aspirin blocks TIF-IA and nucleolar activity provides great promise for the development of new treatments and targeted therapy.’
Previous research has suggested a low-dose 75mg daily aspirin over many years can reduce middle aged people’s risk of stomach, oesophageal and bowel cancer by about a third – and lung, prostate and breast cancer by ten per cent.
People at increased risk of these cancers – for instance due to family history – and not likely to bleed have been advised to discuss with their GP if they might benefit.
Dr Stark said the findings published in Nucleic Acid Research have ‘great significance.’
She said: ‘These data have far reaching implications for understanding of the anti-tumour effects of this agent.
‘In summary, the data presented here open up new avenues of research into nucleolar regulation.
‘They also shed further light on the complex mode of action of aspirin and related non-steroidal anti-inflammatory drugs (NSAIDs).’
First developed to treat arthritis pain, aspirin belongs to a class of drugs called NSAIDs (non-steroidal anti-inflammatory drugs), as does ibuprofen.
These drugs dampen inflammation by blocking pain-producing chemicals called thromboxanes.
Aspirin differs from paracetamol, which has no anti-inflammatory effect and works on a different pain trigger, the chemical cyclooxygenase.
The research was funded by the Medical Research Council and the Biotechnology and Biological Sciences Research Council.
Worldwide Cancer Research, Bowel and Cancer Research and The Rosetrees Trust also supported it.