‘Super’ cancer survivors offer vaccine hope

People who survive multiple separate instances of cancer are believed to hold the key to a future cancer vaccine that could be just a few years away.

Super-survivor Pina Lee of Melbourne has been diagnosed with five different cancers over 14 years. Picture: Aaron Francis

People who survive multiple separate instances of cancer are believed to hold the key to a future cancer vaccine that could be just a few years away.

Researchers at the scientific institute WEHI, RMIT University and the University of NSW, together with Cancer Council Victoria, are studying 16 “super-survivors” who have been diagnosed with a combined 61 different primary cancers across 25 different cancer types, 18 of which are rare.

The scientists believe there is something about the way these super-survivors’ bodies fight cancer that prevents the cancer from spreading.

“These patients are like the canaries in the coal mine,” said lead researcher Clare Scott, joint head of clinical translation at WEHI. “Even when they get a serious cancer diagnosis they can keep the cancer in check, and that’s what is so striking.

“They are giving us a signal that will allow us to really understand what we should be looking at in terms of potential to prevent cancer development.”

The scientists have taken tissue samples from the 16 patients and will study the DNA of their tumours in an attempt to identify common “spelling mistakes” in the genetic sequence of the tumours that cause neoepitopes, which are peptides that arise from genetic mutations.

The scientists will then use blood samples taken from the patients to test whether a particular neoepitope is causing a reaction in the body that prevents the cancer from spreading.

“We’re looking within the tumour for these flags, which are little runs of amino acids,” Professor Scott says. “These protein tags could be recognised in some way by the body and trigger a response from the body to actually shut down the cancer itself, to wall it off if you like, and in doing so, prevent that cancer from being able to spread."

Once the scientists can identify which neoepitopes are triggering the body to halt metastasis in cancer cells, they will use peptides from these chains of protein to create a cancer vaccine.

RMIT professor Magdalena Plebanski will be in charge of creating a cancer vaccine once the functional neoepitopes that are common across many different types of cancers are identified.

“If we find the neoepitopes that may be associated with preventing metastasis or may be involved in metastasis, and we can then get the immune system to attack them, then we could have a really powerful vaccine that could be generic,” Professor Plebanski said.

“Because it would be something common between all different types of cancers.”

Melbourne woman Pina Lee is one of the super-survivors who is being studied as part of the research.

Mrs Lee, 58, has been diagnosed with five different primary cancers over the course of 14 years. She was diagnosed with breast cancer at age 45, and has also survived kidney cancer, rare forms of ovarian and pancreatic cancers and a rare form of sarcoma.

“Doctors are a little bit baffled by me at times,” Mrs Lee says. “Sometimes you do wonder ‘why me’ but it’s not a question that I can find an answer for — this is just what I’ve got to deal with.

“I hope that any data or any knowledge that they can get from me can be used to help future generations.”

Colleen Hosking, 82, has survived six separate primary cancers over the course of 40 years. Remarkably, she has required only surgery to treat several of the cancers and has not needed to undergo chemotherapy.

“I sort of thought in the early stages ‘well if they’re not going to give me treatment that means I’m not going to be around for very long’. But actually, it’s been the opposite — I haven’t had to have the treatment and I’m still around. And I do sometimes wonder why.

“I hope that they can find out the reasons why we can have so many cancers and keep surviving.”

Professor Scott said she was confident the team of researchers would be able to create a cancer vaccine for testing within the next three years.

“We believe that we’ve cottoned on to a capacity to control cancer in these individuals that has not been seen before. We believe that this cohort is just so phenomenally full of the right biology, and we believe we have the tools to understand it.

“This is the first time a cancer vaccine has been developed using this approach. We don’t know of any other set of patients who are able to achieve this level of control against these types of cancers.

“It’s just a matter of us understanding the rules of engagement to then come up with the solutions and applying it.

“It’s widely acknowledged that we’re never going to be able to treat our way out of the cancer burden; the only way we can control or reduce the global cancer burden is to prevent cancers. So this is our pitch to try to prevent metastasis.”