Posts tagged ‘Cancer’
Bad weather and a delayed flight might be a recipe for misery – but in one instance 50 years ago it led to a discovery that has saved countless thousands of lives.
The discovery of the Epstein Barr virus – named after British doctor Anthony Epstein – resulted from his specialist knowledge of viruses which caused tumours in chickens plus his skills gained using one of the first commercially-available electron microscopes.
His hunch was assisted by a longer than expected journey of some tumour cells from Uganda, which were nearly thrown in the bin.
But it would never have happened if Epstein’s curiosity hadn’t been fired up by a lecture by the Irish doctor turned “bush surgeon”, Denis Burkitt.
In the lecture, billed as a staff meeting on “The Commonest Children’s Cancer in Tropical Africa”, Burkitt described how he had noticed a number of cases of debilitating tumours which grew around the jawbone of children in specific regions – particularly those with high temperatures and high rainfall.
We now know this as Burkitt lymphoma.
Sir Anthony Epstein, now 93, speaking to the BBC’s Health Check programme, recalls: “I thought there must be some biological agent involved. I was working on chicken viruses which cause cancer. I had virus-inducing tumours at the front of my head. I thought… [it] was being carried by some insect vector, or some tic. That’s why it was temperature-related.”
The Epstein Barr virus belongs to the family of herpes viruses – and is linked to a number of different conditions, depending on where you live.
Most people are infected with the Epstein Barr virus. It’s best known in high-income countries for causing glandular fever which causes a sore throat, extreme fatigue and swollen glands in the neck.
According to Dorothy Crawford, emeritus professor of microbiology at Edinburgh University, up to 95% of all adults are infected with the virus.
“The virus is spread in childhood at different rates – in the saliva, so through close contact. In African countries most children have it by the age of two because they share cups in their household.
“The rate is lower in middle-class areas of England, so if you haven’t already been exposed by your early teens it can cause glandular fever.”
This has given it the nickname the kissing disease because, she explained: “People kissing in the back row of the cinema exchange more saliva than young children sharing toys.”
Epstein asked for samples of the tumours from Burkitt and they were sent back on overnight flights from Uganda.
For almost three years Epstein’s efforts to retrieve virus from the tumour cells failed, despite trying several culture methods used successfully for other viruses like influenza and measles.
In the end bad weather came to the rescue.
Fog delayed one flight which was diverted to Manchester, 200 miles from London. So the sample taken from the upper jaw of a nine-year-old girl with Burkitt lymphoma didn’t get to Epstein until late one Friday afternoon on 5 December 1963.
At that point it looked past its sell-by date.
“The fluid was cloudy. This suggested it had been contaminated on the way,” Epstein said.
“Was it full of multiplying bacteria? Before we threw it away I looked at it under a wet preparation microscope and saw huge numbers of free-floating, healthy looking tumour cells which had been shed from the edge of the tumour.”
Traditionally, growing cells successfully in culture had involved sticking them to a glass surface for support, but the lymphoma cells seemed to favour growing in a suspension.
Once all other conventional tests for identifying the virus from the cultured cells had failed, Epstein tried electron microscopy. The very first grid square he viewed included a cell filled with herpes virus.
Exhilarated by what he’d seen, Epstein went for a walk in the winter snow and came back feeling calmer.
“I was extremely frightened in case the electron beam [of the microscope] burned up the sample. I recognised at once the herpes virus – there were five then, now nine. Any of the then-known ones would have wiped the culture out when they were replicating but this wasn’t happening. I had the feeling that this was something special.”
Our understanding of this pervasive virus, named after Epstein and one of his PhD students Yvonne Barr who helped to prepare the samples, has increased over the years since Epstein confirmed his findings with American virologist colleagues.
Burkitt’s data helped to identify that the tumour named after him was seen in children with chronic malaria, which reduced their resistance to the Epstein Barr virus, allowing it to thrive.
But most of us live quite happily with the virus.
“If you disturb the host-virus balance in any way then changes take place which lead to very unpleasant consequences,” says Epstein.
“Once the link between Epstein Barr virus and Burkitt lymphoma was established, other seemingly unrelated conditions followed. These include a cancer at the back of the nose which is the commonest cancer seen in men in southern China and the second commonest in women in the same region.
There is also a link to Hodgkins lymphoma, a cancer of the white blood cells.
“Each one came out of the blue,” according to Epstein, “and we’ve just heard about another. About 20% of Japanese cancers of the stomach are associated with the virus.”
Yet another connection was made by Professor Dorothy Crawford, while waiting for the lift at the Royal Free hospital in London.
“It’s such a tall building everyone meets outside the lifts. I was standing next to a renal [kidney] transplant surgeon and overheard him say they’d just had their first case of post-transplant lymphoma. So I went with him to the pathology department and asked for some sections of the tissue to look at under the microscope.”
Burkitt lymphoma can now often be treated successfully with chemotherapy.
At a recent meeting in Oxford of the Epstein Barr Virus Association future directions for research were explored.
Attention is now focusing on a vaccine for the Epstein Barr virus – and some efficacy has already been demonstrated.
Epstein hopes that a vaccine will lead to the kind of success seen in other cancers caused by viruses – such as Hepatitis B and the human papillomavirus, which cause liver and cervical cancer respectively.
New research suggests that cancer could have existed 3,000 years ago, according to journal Plos One.
The discovery was made in the skeleton of a 25-year-old man who lived in ancient Egyptian times.
Pallab Ghosh reports.
Vitamin C has long been used as an alternative cancer therapy but evidence is mixed
High-dose vitamin C can boost the cancer-killing effect of chemotherapy in the lab and mice, research suggests.
Given by injection, it could potentially be a safe, effective and low-cost treatment for ovarian and other cancers, say US scientists.
Reporting in Science Translational Medicine, they call for large-scale government clinical trials.
Pharmaceutical companies are unlikely to run trials, as vitamins cannot be patented.
Vitamin C has long been used as an alternative therapy for cancer.
In the 1970s, chemist Linus Pauling reported that vitamin C given intravenously was effective in treating cancer.
Further studies are needed before we know for sure what benefits high dose vitamin C may have for patients”
Dr Kat ArneyCancer Research UK
However, clinical trials of vitamin C given by mouth failed to replicate the effect, and research was abandoned.
It is now known that the human body quickly excretes vitamin C when it is taken by mouth.
However, scientists at the University of Kansas say that when given by injection vitamin C is absorbed into the body, and can kill cancer cells without harming normal ones.
The researchers injected vitamin C into human ovarian cancer cells in the lab, into mice, and into patients with advanced ovarian cancer.
They found ovarian cancer cells were sensitive to vitamin C treatment, but normal cells were unharmed.
The treatment worked in tandem with standard chemotherapy drugs to slow tumour growth in mouse studies. Meanwhile, a small group of patients reported fewer side-effects when given vitamin C alongside chemotherapy.
No patent potential
Co-researcher Dr Jeanne Drisko said there was growing interest in the use of vitamin C by oncologists.
“Patients are looking for safe and low-cost choices in their management of cancer,” she told BBC News. “Intravenous vitamin C has that potential based on our basic science research and early clinical data.”
One potential hurdle is that pharmaceutical companies are unlikely to fund trials of intravenous vitamin C because there is no ability to patent natural products.
“Because vitamin C has no patent potential, its development will not be supported by pharmaceutical companies,” said lead researcher Qi Chen.
“We believe that the time has arrived for research agencies to vigorously support thoughtful and meticulous clinical trials with intravenous vitamin C.”
Dr Kat Arney, science communications manager for Cancer Research UK, said there was a long history of research into vitamin C for treating cancer.
“It’s difficult to tell with such a small trial – just 22 patients – whether high-dose vitamin C injections had any effect on survival, but it’s interesting that it seemed to reduce the side-effects of chemotherapy,” she said.
“Any potential treatment for cancer needs to be thoroughly evaluated in large clinical trials to make sure it’s safe and effective, so further studies are needed before we know for sure what benefits high dose vitamin C may have for patients.”
Nearly a third of a million people are being diagnosed with cancer each year in the UK, according to the charity Cancer Research UK.
It says around 50,000 more people are finding out they have cancer every year than a decade ago.
The rise is due to more people living to a ripe old age.
Meanwhile, research by the University of Exeter suggests patients want cancer symptoms to be checked out more quickly than NHS guidelines recommend.
Age is the biggest risk factor for cancer.
And as life expectancies have increased in the UK, so too has the number of people being diagnosed with cancer.
In 2001, 283,000 people were told they had cancer. This increased to 331,000 in 2011.
Dr Harpal Kumar, chief executive of Cancer Research UK, said: “As the population ages, more people than ever before will be told, ‘You have cancer’.
“Research is the only way we’ll be able to reduce the devastating impact of the disease. One day we will beat cancer. The more research we do, the sooner that day will come.”
The World Health Organization says the number of people being diagnosed around the world each year leapt to more than 14 million in 2012, up from 13.7 million in 2008.
Breast cancer is one of the commonest types.
Eluned Hughes, of Breakthrough Breast Cancer, says: “Breast cancer is not a done deal and, as increasing numbers of people face the possibility of one day being told they have breast cancer, this is exactly why it is imperative that we continue our research.”
Meanwhile, a study on 3,649 people, published in the Lancet Oncology, suggested patients wanted any symptoms linked to cancer to be checked as quickly as possible for peace of mind.
The researchers say patients often need to have a one-in-20 chance of having cancer, based on their symptoms, before further tests to identify a tumour.
The study suggests the majority of patients want to be checked out when there is a one-in-100 chance of cancer.
Dr Jonathan Banks, of the University of Bristol, said: “This large study provides a clear and comprehensive account of public preference for investigation for cancer.
“It shows for the first time that there’s a strong preference for diagnostic cancer testing, even if the risk is very low.
“This desire far exceeds what is actually being offered by the NHS, and we hope the findings can help policymakers and doctors in shaping guidelines and practice.”
Thousands of people who go on to be diagnosed with cancer were not referred to a specialist by their GP.
NHS England data from around 4,000 GP practices suggests symptoms were picked up in other ways, for example in accident and emergency departments.
The NHS said not all cancer patients went to their GPs and the figures were not a clear measure of performance.
Patients who do go to their GP with cancer symptoms are seen within two weeks in 95% of cases, the NHS said.
Health Secretary Jeremy Hunt said the government was tackling the “unacceptable variation” across different practices.
National performance data allows patients to look up their GP surgery and see how it performs against dozens of diagnosis and treatment indicators.
NHS England collected the figures on cancer referral rates from GP surgeries across the country as part of a drive to make the health service more transparent.
The NHS has a target that 95% of patients with suspected cancer should be seen by a specialist within two weeks – a target it says is consistently met.
But in around half of the GP practices sampled, fewer than 50% of patients on their books who were subsequently found to have the disease were referred to a specialist by their doctor.
Sean Duffy from NHS England said: “We know that early diagnosis is the single most important factor in cancer survival, and that’s why patients who visit their GP with ‘red flag’ symptoms like very persistent coughs, blood in urine or faeces or breast lumps should always be referred for further tests on two-week pathways.
“But not all patients visit their GP about these symptoms and others may have cancer without developing specific symptoms.
“These patients will therefore have their cancer diagnosed after going to a hospital as an emergency, or have it spotted incidentally while receiving treatment for another, unrelated issue.”
Rigorous inspection regime
Stuart Barber, from Beating Bowel Cancer, said it was “intolerable” that some patients were having to wait.
“GPs have the tools. There are clear symptoms, there is a clear screening programme and if a patient visits their doctor with what are symptoms of bowel cancer they should have the confidence they are going to be referred quickly,” he said.
Mr Hunt said: “Every single patient in the NHS has the right to the very best care – and to see a GP who can spot cancer symptoms early enough to make a difference.
“That’s why we’ve introduced a rigorous new inspection regime for GP surgeries.”
Under the regime, a new chief inspector would rate each surgery so the government could take action against those “not up to scratch”, he said.