A 'Trojan Horse' molecule developed by
WAIMR provides a new weapon to use
against pancreatic cancer.
Image: iStockphoto

Pancreatic cancer has a tough new opponent, a molecule described as a ‘Trojan horse’ and developed by a Western Australian Institute for Medical Research (WAIMR) team.

The molecule is able to target a type of pancreatic tumour, eventually enabling the body’s immune system to attack the cancer.

A strong inflammatory agent is packed into the molecule using lipid-nanotechnology, to target a site and attract millions of immune cells to kill the tumour.

Lead researcher Professor Ruth Ganss says the team uses lipid vesicles to create the molecule and the lipid is then covered with peptides called RGR.

“The outer surface of the lipid vesicle is coated with a small molecule (a peptide) which binds very specifically to pancreatic tumours,” Prof Ganss says.

“It does not bind to other blood vessels in normal tissue or in other tumour types.

“This has been shown previously by other researchers, however, identification of peptides or antibodies which bind to blood vessels in other tumour types is a very active research field and I expect that we will identify a whole panel of useful ‘homing’ devices.”

According to Prof Ganss, immune cells are attracted to the tumour and are more active in the tumour environment, becoming effective killers of tumour cells.

“We called it ‘Trojan horse’ because we ‘smuggle’ a substance into tumours and then immune cells start attacking from the inside.”

According to Prof Ganss, the process has been shown to improve survival rates.

“Mice which are predisposed to develop pancreatic cancer normally succumb at about 30 weeks of age,” she says.

“In the treatment groups, all mice survived until week 35 and 30 percent of all treated mice survived until week 45.”

The molecule also works to avoid toxic side effects.

“For the inflammatory agents to be effective at the tumour site, we would have to inject a high dose of the free substance which ultimately has toxic side effects because it acts in many parts of the body,” she says.

Prof Ganns says the team hope to package agents into liposomes and concentrate it in tumours.

“So it is effective at smaller doses and only where we need it.”

While other clinical trials use liposome-encapsulated agents and there are several existing patents for lipid formulations, Prof Ganns says the novel aspect of the study is that inflammatory reagents are used to activate the immune system, which then kills tumour cells.

Clinical trials may begin in 5-10 years, depending on pharmaceutical company interest.

The research was published in The Journal of Immunology on July 15.