Infusions of coxsackievirus were given to 15 non-muscle invasive bladder cancer patients one week before undergoing surgery to remove and examine tumours, in all cases cancer cells had been destroyed and in one case all traces of the disease were gone.
Bladder cancer is the tenth most common type of cancer, and there are 10,000 diagnosis in the UK alone annually. Treatment via a catheter to the bladder reduced the size of all tumours while having no significant side effects in any of the patients according to the scientists.
Typically tumours in the bladder don’t have immune cells which makes this disease difficult to treat; this study suggests infusions with CVA21 was able to inflame tumours and cause immune cells to rush into the cancerous environment to target and kill the cancer cells. Once the virus targeted cancer it replicated itself and became more powerful.
“The virus gets inside cancer cells and kills them by triggering an immune protein – and that leads to signalling of other immune cells to come and join the party.”
The scientists suggest that the virus could become a universal agent to fight cancer, and either work with or replace conventional treatments such as chemotherapy. The team hopes that this treatment will be available in 3 years to bring hope to patients with diseases that are hard to treat.
“We are very excited about it. The virus gets into the cancer and replicates, like a little factory of viruses. It heats up the tumour environment, and is very specific in targeting the cancer – it had the least toxicity I have seen for years.” says Prof. Hardev Pandha. “It’s almost like a universal agent – once it gets in it kills the cancer. It could be combined with lots of other treatments.”
Tissue samples were examined after surgery which revealed only the cancerous cells were targeted, other cells were left intact. The cold virus was found to have infected cancerous cells and replicated causing the cells to rupture and die. Urine samples after treatment detected shedding from the virus indicating once virally infected cancer cells died the replicated virus continued to attack more cancerous cells.
“Reduction of tumour burden and increased cancer cell death was observed in all patients and removed all traces of the disease in one patient following just one week of treatment, showing its potential effectiveness. Notably, no significant side effects were observed in any patient.”
“Traditionally viruses have been associated with illness – however in the right situation they can improve our overall health and wellbeing by destroying cancerous cells,” said Dr Nicola Annels, “The use of the viruses could transform the way we treat cancer and could signal a move away from more established treatments such as chemotherapy.”
According to Dr. Mark Linch, “Although at an early stage, these initial results are encouraging. It will be really interesting to see how this new virus-based therapy fares in larger trials in people with non-muscle invasive bladder cancer, particularly in combination with newer immunotherapies.”
