Risks of long-term aspirin use ‘outweighed by cancer benefits’

Past research has linked long-term aspirin use to adverse side effects, such as internal bleeding. But according to a new study, the benefits of longstanding aspirin therapy outweigh such risks; it can significantly reduce the risk of major cancers of the digestive tract, including stomach, bowel and esophageal cancers.

 

The research team, led by Prof. Jack Cuzick, head of the Centre for Cancer Prevention at the Queen Mary University of London in the UK, recently published their findings in the journal Annals of Oncology.

Aspirin, also known as acetlylsalicylic acid (ASA), is a salicylate drug commonly used to reduce minor aches and pains, inflammation and fever. In long-term low doses, the drug is also used as an antiplatelet for patients at high risk of heart attackand stroke.

There has been much debate surrounding the benefits of long-term aspirin therapy. Previous studies have suggested it can reduce risk of ovarian cancer and improve colon cancer survival, while others claim it can cause harm, with one study suggesting it increases the risk of age-related macular degeneration.

In this latest research, Prof. Cuzick and his team set out to determine whether the health benefits of continued aspirin use outweigh the risks.

Taking daily aspirin ‘important for reducing cancer risk’

To reach their findings, the team conducted an analysis of all available evidence from an array of studies looking at the beneficial and harmful effects of aspirin use.

The researchers estimated that if individuals aged 50-65 took a daily 75-100 mg dose of aspirin for 5-10 years, the number of bowel cancer cases could be reduced by 35% and deaths by 40%, while rates of stomach and esophageal cancers could be cut by 30% and deaths by 35-50%.

Overall, they estimate that daily aspirin use for 5-10 years could provide a 9% reduction in the number of cancers, strokes and heart attacks in men, and a 7% reduction in women. Over a 20-year period, they estimate the number of deaths from all causes could be reduced by 4%. No benefits were found until individuals used aspirin for a minimum of 3 years.

But the researchers note that continued aspirin use does increase the risk of bleeding in the digestive tract. They found that individuals aged 60 who took aspirin daily for 10 years increased their risk of gastrointestinal bleeding by 1.4%, from 2.2% to 3.6%. However, they note that this is only likely to be life-threatening in around 5% of people.

“The risk of bleeding depends on a number of known factors which people need to be aware of before starting regular aspirin, and it would be advisable to consult with a doctor before embarking on daily medication,” notes Prof. Cuzick.

In addition, they found that continuing aspirin use increased the risk of peptic ulcer by 30-60%.

But despite these side effects, Prof. Cuzick believes that long-term aspirin therapy could be vital to cancer prevention:

“It has long been known that aspirin – one of the cheapest and most common drugs on the market – can protect against certain types of cancer. But until our study, where we analyzed all the available evidence, it was unclear whether the pros of taking aspirin outweighed the cons.

Whilst there are some serious side effects that can’t be ignored, taking aspirin daily looks to be the most important thing we can do to reduce cancer after stopping smoking and reducing obesity, and will probably be much easier to implement.”

The team notes that further research is warranted to better pinpoint those who are most likely to benefit from long-term aspirin use and who is at highest risk of gastrointestinal bleeding.

Earlier this year, Medical News Today reported on a consumer update from the US Food and Drug Administration (FDA), stating that while daily low-dose aspirin use can prevent heart attack or stroke for those who have already had one, there is insufficient evidence to support its use for prevention of first-time heart attack or stroke.

Written by Honor Whiteman

 

Study explains why some brain tumors are more common in men

Some brain tumors, such as glioblastomas – the most common and invasive brain tumors in humans – are more prevalent in men than women and are often more harmful, but the reasons behind this have been unclear. Now, researchers from Washington University in St. Louis, MO, may have shed some light on the issue.

In a study published in The Journal of Clinical Investigation, the researchers reveal that a protein associated with reduced cancer risk – retinoblastoma protein (RB) – is much less active in the brain cells of men than women.

Dr. Joshua Rubin and colleagues began their research by conducting a series of experiments on a cell model of glioblastoma. This involved exposing male and female brain cells to a tumor growth factor and a number of genetic alterations.

From this, the team confirmed that tumors grow faster and more frequently from male brain cells than they do from female brain cells.

To try and determine the mechanisms behind this, the researchers analyzed three genes – neurofibromin, p53 and RB – that normally lower tumor development by curbing cell division and survival. The researchers note that in many cancers, these particular genes are disabled or mutated.

Disabling RB protein increased cancer susceptibility

Dr. Rubin and colleagues found that, compared with female brain cells, the RB protein was significantly more likely to be inactivated in male brain cells.

Furthermore, they found that disabling the RB protein in female brain cells caused them to be just as susceptible to cancer than the male brain cells.

Dr. Rubin says these findings may have important implications for treating patients with brain tumors and identifying those at risk:

“This is the first time anyone ever has identified a sex-linked difference that affects tumor risk and is intrinsic to cells, and that’s very exciting.

These results suggest we need to go back and look at multiple pathways linked to cancer, checking for sex differences. Sex-based distinctions at the level of the cell may not only influence cancer risk but also the effectiveness of treatments.”

He adds that as well as brain tumors, there are other cancers – such as some liver cancers – that are more common in men than women.

“Knowing more about why cancer rates differ between males and females will help us understand basic mechanisms in cancer, seek more effective therapies and perform more informative clinical trials.”

Should clinical data be reviewed by gender?

RB is currently being evaluated as a drug target in clinical trials. Researchers are attempting to trigger the anti-tumor effects of the protein in the hope it will prolong survival of cancer patients.

But Dr. Rubin says the team’s findings should prompt the researchers of these trials – and those involved in other trials – to look at data in a different way.

“In clinical trials, we typically examine data from male and female patients together, and that could be masking positive or negative responses that are limited to one sex,” he explains. “At the very least, we should think about analyzing data for males and females separately in clinical trials.”

Last month, Medical News Today reported on a study published in Nature Communications, which claimed to reveal one reason why glioblastomas spread so rapidly. The team found that the cancer cells hijack and feed off the brain’s blood vessels, weakening the blood-brain barrier.

Written by Honor Whiteman

http://www.medicalnewstoday.com/articles/280516.php