Success in new brain cancer vaccine
Wellington neurosurgeon Mr Martin Hunn has successfully tested a new vaccine for aggressive brain cancer on mice.
It stimulates the immune system to attack tumours and will help develop a vaccine for people with Glioblastoma multiforme (GBM) in the future.
The chances of surviving this type of cancer are slim as the tumour becomes rapidly resistant to treatment like surgery, radiotherapy and chemotherapy.
About four cases are reported per 100,000 New Zealanders and on average people die within 15 months of being diagnosed.
Results recently published in the Clinical Cancer Research journal showed the vaccine – containing tumour cells and an immune-boosting agent derived from marine sponges – was strong enough to kill glioma tumours in mice.
"It’s a vital step and we learned a huge amount about how vaccines work and how the immune system responds," Mr Hunn said.
Early indications showed humans had the immune system "machinery" needed for this treatment to work.
Immunotherapy, which treats a disease using the body's own defence system, has been explored as a potential treatment for brain cancers for some time.
Mr Hunn and colleagues at Wellington Hospital and the Malaghan Institute recently finished the first phase of a GBM vaccine trial at Wellington Hospital, the results of which will be released next year.
The vaccines used in these types of trials are typically created from the patient’s tumour tissue.
Dendritic cells - which spark the attack against the tumour - are needed but if someone is too sick it can be difficult to isolate enough of these cells from the blood.
After turning away people who were too sick to take part in the trial, Mr Hunn and Associate Professor Ian Hermans went back to the laboratory to see if they could create a vaccine without dendritic cells.
The vaccine was tested on mice and in some instances tumours completely disappeared.
While the trials were not revolutionary, they highlighted the need to switch off a tumour’s ability to suppress the immune system, Mr Hunn said.
"It’s a huge problem, as the tumour evolves it develops all sorts of mechanisms to protect itself from the immune system.
"We not only have to have a strong vaccine, but we need to be able to shut off some of these immuno suppressant mechanisms."
More clinical trials are planned, potentially using a similar vaccine to the one used in mice, Mr Hunn said.
The Dominion Post