Blood test for cancer 10 years away

15/10/2010

It was a groundbreaking project with Guernsey women at its heart and now researchers view blood, urine and saliva collected here decades ago as some of the most precious in the world. Nicci Martel reports on how work on the samples has expanded to include other cancers and heart disease.

WHEN Sister Elizabeth Lincoln started collecting blood, urine and saliva samples from Guernsey women in 1964, there was no way she could have known that she was accumulating what would become one of the most precious collections of blood in the world.

The project, which was instigated by the Imperial Cancer Research Fund, demonstrated incredible foresight and its only now, nearly 50 years later, that the technology for unlocking the secrets within these samples has caught up.
The vast collection provided from 11,000 women is the basis for groundbreaking research at the University of Southampton. But what started out four years ago as a mission to find a blood test for early detection of breast cancer has expanded to include work on other cancers and also heart disease.

Leading the research is Professor Paul Townsend, a specialist in molecular cell biology. He believes that within 10 years he will have a blood test for breast cancer and much more besides.

The progress weve made is huge. Technology has developed really, really fast and really, weve become one of the world leaders in this area, he said.
The Guernsey samples are brilliant. Its the best collection in the world because its totally controlled. I think it was a brave decision for Guernsey to take part in the research. It was probably very costly and I doubt something like it would ever be possible today.

Blood circulates tissue, including cancer cells, in the body, picking up molecules along the way. Cancer cells produce proteins. These proteins are called biomarkers, they are cancer fingerprints, and if Paul can identify what these are and establish a clinical test, breast cancer could be diagnosed at a very early stage using a simple blood test.

The result would be early diagnosis and hopefully much better patient outcomes. But it doesnt end there. So far, 27 biomarkers have been validated, but discovering how they work could help identify which treatments they will be responsive to.

For instance, what treatment would best suit those with sporadic cancer, what would be best for hereditary cancer, and which has the better prognosis?  
It is thought that a long exposure to the hormone oestrogen increases the risk of breast cancer, which is why women over the age of 50 qualify for free screening.

But although the majority of cases occur in this age group, 5% of breast cancers diagnosed in the UK are in women aged 40 or younger.

Of these early-onset breast cancers, 9-10% are hereditary, which means the women are carriers of the BRCA 1 or 2 genes. These can be tested for, but the most appropriate treatment for these patients is uncertain.

Some women with these genes opt for a prophylactic [preventative] mastectomy, they think its the best treatment, which is scary to say the least. There are all sorts of ethical and medical issues involved.

Proteomics the study of protein structure and functions holds the key to understanding whether those with hereditary cancer should be treated differently.

Another example is [the drug] Herceptin. It works in only 7% of patients, yet up to 97% of breast cancer patients ask for it. This is a huge waste of money and false hope because it only works with certain molecule structures. We need to work out who is sensitive to certain drugs, said Paul.

Looking for biomarkers, he said, was less like looking for a needle in a haystack and more like looking for a needle in an entire county: There have been a lot of blind alleys.

It is meticulous work that generates a vast amount of information. Improved technology has made a significant difference, as has working with international partners such as Dr Spiros Garbis, who is based in Athens the Bill Gates of proteomics.

But part of the challenge is to create a final test that can be done using accepted techniques, not cutting-edge equipment.

It currently costs 150 to analyse a sample by proteomics and that needs to get down to 50p if its ever going to be of clinical use.

Also, whatever we find we have to validate. We have to use blood from elsewhere in the world.

What we find might be wonderful for Guernsey, but we need to make it global its got to apply to people in Japan, Paul said.

But without that initial entrepreneurial and risky funding from Guernsey, it wouldnt have been possible.

It was announced this week that a diagnostic marker has been identified by scientists at Cancer Research. Again using proteomics, they may have discovered that a protein found in urine is affected by a genetic change linked to prostate cancer.

Potentially, a simple urine test could be developed to diagnose that disease. However, its still early days.

Precious Guernsey collection
ACADEMIC Surgical Fellow Dr Bashar Zeidan, who was awarded the 12th States of Guernsey Fellowship by HSSD, has joined the project full-time to drive forward the work on breast cancer.

Ive temporarily given up surgery because I always wanted to do research and part of my training could give me the flexibility to take time out and do it, said the 32-year-old.

Breast cancer, for me, is one of the main areas of surgery and I think the collection we have is one of the most precious in the world because it allows us to go back in time by 50 years.

Around 45,000 new patients are diagnosed each year and of those, 12,500 die. Theres big room for improvement and thats where our work comes into place.
In proteomics, once a protein mass has been found it needs to be identified. First it needs to be purified, then severed from the serum to get one single protein. Once isolated, it can be named and worked on at a cellular level.
We need to know why some patients respond better than others to certain treatment. Thats the key to improving treatment response, he said.
If we didnt believe we could do it, we wouldnt try. We strongly believe in it. There are ups and downs, but now we know were doing
things right.

Prostate cancer samples needed
THE research undertaken by Professor Paul Townsend and the team is now being applied to other diseases, most notably prostate cancer.

It is one of the most exciting developments of the last two years and Dr Samantha Larkin, who was awarded the 2010 Guernsey Fellowship by the Wessex Medical Trust, has been undertaking the project.

I think prostate cancer has been under-studied for many years the focus has always been on breast cancer. Its not as well understood, but that is changing, said the 31-year-old.

About 10,000 men die from prostate cancer each year and in the last 30 years prostate cancer rates in Great Britain have almost tripled, she said, adding that much of the increase in reported deaths is due to the use of the PSA test and better detection. Incidence is rising but the mortality rate stays the same why is that not going down?

Although prostate specific antigen testing has improved the detection, it is not without flaws. PSA is a protein produced by the prostate gland. More is produced with age, but a higher level of PSA can also be caused by cancer.
A study in the US showed that the test only detects 20% of prostate cancers and of those missed, 60% will be aggressive, said Sam.

It is her aim to find a test to identify the aggressive form of this disease. That would mean invasive treatment strategies could be targeted at men who really need it.

About three out of four men diagnosed will be fine, but for a proportion of that other quarter, they will have an aggressive form of the cancer. The basis of our project is to look at the difference between the slow-growing and fast-growing disease using biomarkers. Im looking for a prognostic marker, not a diagnostic one, although I prefer to say aggressive marker.

Its a mammoth task and it involves using mass spectronomy a method of determining particle mass and composition to analyse thousands of proteins. Ninety per cent of all proteins in the blood comprise just nine proteins, with 12 proteins making up another 9%.

Its that final 1% that we really want to look at and its made up of two-to-three thousand different proteins of which about 15 are going to be of interest.

To carry out the research, Sam needs blood samples, which is why she is appealing to local men to donate: anyone who has had a raised PSA test or who has had prostate cancer in the past, or has the disease now. It is hoped a collection of at least 200 samples can be obtained.

Islanders have excellent longevity, theres a good standard of health care, and it is a stable population. When you are looking for biomarkers, if you use blood from a migratory population you get what we call background noise, said Sam.
The Medical Specialist Group will be coordinating the collection and the blood samples will be collected and processed at the PEHs Pathology Department before being transferred to the laboratory in Southampton.

We realise that this is a big request, but the potential benefit to future generations is so great that we hope men will be willing to come forward, just as women did so many years ago, said Roger Allsopp, chairman of Hope for Guernsey, the local branch of the Wessex Medical Trust.

Medical research is not cheap. It requires a huge amount of funding and the charity Hope For Guernsey has donated thousands in the last four years.
Roger, who is planning to swim the Channel for a second time to raise money, said the progress made has been staggering.

From the outset, Guernsey has been central to this project, he said. It would not have started without women volunteers and it would not have progressed without islanders continued generosity.
 
* For further information or to volunteer, email hope@msg.gg or call Jessica Cobb on 239928.

The photo shows Professor Paul Townsend, Dr Bashar Zeidan and Dr Samantha Larkin who visited Guernsey to report on the cutting edge of cancer research. (Picture by Tom Tardif, 1036506)

Guernsey Press Article 15th October 2010


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