In a significant step forward for the development of a potential new cancer treatment, scientists have found how a common cold virus can kill tumours and trigger an immune response, like a vaccine, when injected into the blood stream.
Researchers from Britain's Leeds University and the Institute of Cancer Research (ICR) said by hitching a ride on blood cells, the virus was protected from antibodies in the blood stream that might otherwise neutralise its cancer-fighting abilities.
The findings suggest viral therapies like this, called reovirus, could be injected into the blood stream at routine outpatient appointments - like standard chemotherapy - making them potentially suitable for treating a range of cancers.
The study, part-funded by the charity Cancer Research UK and conducted on 10 patients with advanced bowel cancer, confirmed that reovirus attacks on two fronts - killing cancer cells directly and triggering an immune response that helps eliminate leftover cancer cells.
"Viral treatments like reovirus are showing real promise in patient trials. This study gives us the very good news that it should be possible to deliver these treatments with a simple injection into the blood stream," said Kevin Harrington from ICR, who co-led the study and published it in the journal Science Translational Medicine on Wednesday.
Harrington said if viral treatments had been found only to work when injected directly into tumours, that would have been a significant barrier to their widespread use.
"But the finding that they can hitch a ride on blood cells will potentially make them relevant to a broad range of cancers," he said.
Reovirus is being investigated by several research teams around the world - including scientists at Canada's Oncolytics Biotech Inc - because it has shown an ability to infect and kill cancer cells without affecting normal tissue.
"We also confirmed that reovirus was specifically targeting cancer cells and leaving normal cells alone, which we hope should mean fewer side-effects for patients," Harrington said.
Cancer killed 7.6 million people worldwide in 2008, the most recent year for which the World Health Organisation has full data. The number of cancer cases is expected to surge by more than 75 percent across the world by 2030.
The 10 patients in the study were all due to have surgery on tumours that had spread to their livers. During outpatient appointments in the weeks before their surgery, they were given up to five doses of the experimental reovirus treatment.
When researchers looked at pieces of tissue removed during surgery up to four weeks later, they found what they described as "viral factories" of active virus in the tumour - but not in the normal liver tissue.
This confirmed the reovirus had been delivered specifically to the cancer cells after being injected into the blood stream.
"It seems that reovirus is even cleverer than we had thought," said University of Leeds' researcher Alan Melcher.
"By piggybacking on blood cells, the virus is managing to hide from the body's natural immune response and reach its target intact. This could be hugely significant for the uptake of viral therapies like this in clinical practice."
There were some 216 million cases of malaria worldwide in 2016, an increase of five million from the year before, according to the World Health Organization.
Cataract surgeries project to be expanded in scope to include fight against fistula
Turkey to create an automatic control system to keep records of African patients, Health Ministry official says
Ibb and al-Hodeidah provinces are the hardest-hit by the disease
Association of the Friends of Africa provides health and humanitarian services all over the African continent
Food and Agriculture Organization representative praises professionalism of Turkish government
People will move from vulnerable to more viable areas within their countries, report says
The conference opened hours after the United Nations issued its 2018 World Water Development Report warning that about 3.6 billion people, or half the world's population, already live in areas where water can be scarce at least one month a year.
While it is generally accepted that being overweight increases a person's disease risk, some researchers have recently suggested that carrying extra weight does not actually boost death rates for some, particularly the elderly.
29,000 ducks will be culled by Dutch Food and Consumer Product Safety Authority
After a top court last month ruled driving bans in some city zones for the most polluting diesel vehicles were legal, German commuters, politicians, environmentalists and the mighty car industry have been exchanging blows over potential blanket exclusions.
South Africa has experienced worst outbreak of Listeriosis in history with 180 deaths recorded
Cholera outbreak has killed at least 88 people since last October
New analysis finds almost half of American teenage girls were obese and more than 14 percent of boys aged 2 to 5
Tens of thousands of people have fled an upsurge of fighting in the east of the Democratic Republic of Congo this year, many of them arriving weak and unwell at Ugandan camps that are struggling to accommodate them.
CDC flu season update reveals season appears to have peaked in 13 states