A Genetically modified virus that kills cancer cells and destroys their hiding places has been developed by British scientists.
It targets both cancer cells and healthy cells that are tricked into protecting the cancer from the immune system.
Fibroblasts, the most common type of cell in connective tissues, are vital in the body’s healing process, but they can get hijacked by cancer-associated fibroblasts or CAFs.
These then help tumours grow, spread and evade therapy.
Currently, any therapy that kills the “tricked” fibroblast cells may also kill healthy fibroblasts throughout the body – for example in the bone marrow and skin – causing illness during treatment.
Using a virus called enadenotucirev, already being used in clinical trials as a cancer treatment, experts were able to programme the virus to only attack cancerous cells.
The virus uses a protein to bind cancerous cells to immune cells to destroy the disease.
These immune cells normally can’t find unhealthy, cancerous cells as they are hidden by CAFs.
Lead author Dr Kerry Fisher, from the Department of Oncology at the university, said: “Even when most of the cancer cells in a carcinoma are killed, fibroblasts can protect the residual cancer cells and help them to recover and flourish.
“Until now, there has not been any way to kill both cancer cells and the fibroblasts protecting them at the same time, without harming the rest of the body.
“Our new technique to simultaneously target the fibroblasts while killing cancer cells with the virus could be an important step towards reducing immune system suppression within carcinomas and should kick-start the normal immune process.
“These viruses are already undergoing trials in people, so we hope our modified virus will be moving towards clinical trials as early as next year to find out if it is safe and effective in people with cancer.”
The virus was successfully tested on human tissue cells from cancer patients and prostate cancer tumours, without causing abnormal immune responses that usually make people sick during cancer treatments like chemotherapy.
The study, which was funded by the Medical Research Council (MRC) and Cancer Research UK, was published in the journal Cancer Research.
Dr Nathan Richardson, head of molecular and cellular medicine at the MRC said: “This innovative viral delivery system, which targets both the cancer and surrounding protective tissue, could improve outcomes for patients whose cancers are resistant to current treatments.
“Further clinical studies will be crucial to determine that the stimulation of the patient’s immune system does not produce unintended consequences.”