New research out of Quebec gives hope for rare childhood cancer therapy

A joint university study has found that a pathway to a therapy program against a rare and deadly pediatric brain tumour is now possible.

The study was led by scientists from the McGill University Health Centre (MUHC) 's Research Institute and the Baylor College of Medicine in Texas.

Due to a lack of effective treatment, the tumours—called Posterior fossa group A (PFA) ependymoma—have the highest recurrence rate and poorest prognosis of all childhood cancers.

MUHC senior scientist Dr. Nada Jabado explained that so far, the treatment available includes surgery and radiation therapy, but the cancer tends to come back.

"This is a cancer that affects very young children, infants and until the age of six and seven. Sometimes a little later, but mostly infants," said Jabado. "Close to 70 per cent will die within the first years, and up to 90 later. Some will make it, but it is rare."

The research investigated interactions between regions of the genome that are unique to PFAs. They named these predictable sections TULIPs or Type B Ultra-Long Interactions in PFAs.

"[TULIPs] are three-dimensional structures within the nucleus that are very specific to this tumour, only present in this tumour, that makes the cell keep a very undifferentiated and aggressive phenotype," said Jabado. "By understanding what keep those structures together, we could aim to provide a treatment, because if we could have them dissolve, [TULIPs] will be remove and cells will mature better and we may provide a break to those kids."

Senior and lead author of the study, Marco Gallo, said in a statement that TULIPs interact with other over long distances, like from one end of a chromosome to another, with surprising strength.

"TULIPs on different chromosomes can also converge and strongly interact with each other," said Gallo. "We also found that regions outside TULIPs appear more relaxed overall. This is important because TULIPs are linked to the cell's function."

By inhibiting specific proteins carried in TULIPs, the team witnessed "weaker interactions between TULIPs and impaired PFA cell survival," according to the statement.

It noted that their observations suggested that interactions between TULIPs "are important for PFA cell viability, opening up new potential targets for treatment."

The research started about five years ago, and for the treatment to reach clinical trials, it still might take a year or two, "and I'm being very generous," Jabado said. "The next step is to validate that if we use this inhibitor, the one that we use in the paper, on a larger set of samples, and across multiple labs and models, we're seeing similar results."