A breast cancer drug could be used to shrink the most common and deadly form of childhood brain tumour.
The discovery, made by The University of Queensland's Institute for Molecular Bioscience and the Fred Hutchinson Cancer Research Center in Seattle, has led to a Phase II clinical trial using the drug Palbociclib to treat children with medulloblastoma - a fast-growing, high-grade tumour.
If successful, it's hoped the drug would be combined with other traditional therapies to lessen the treatment burden these very young children face and improve survival, which currently stands at less than 10 per cent.
"The tumour that we work on is the most common solid malignant paediatric brain tumour in children and one of the most aggressive," said UQ researcher Dr Laura Genovesi.
"With current therapies these children have devastating side effects, some have 14 surgeries in one year and it has a massive effect on the developing brain," she said. "If we could reduce the number of surgeries to five that would be one quite realistic outcome."
Using genetic sequencing technology, researchers examined the genetic code of medulloblastoma to predict whether these tumours may respond to already-approved drugs.
The analysis led them to Palbociclib, an oral drug approved in 2015 for the treatment of metastatic breast cancer, which doesn't result in common side effects such as hair loss and nausea.
Animal experiments then showed the drug rapidly worked to arrest the growth of the brain tumours in mice engineered with the same genetic mutations as humans with the disease.
Unexpectedly, the drug also shrank the tumours to a survivable size, say the researchers.
Some tumours did, however, re-occur once treatment with Palbociclib stopped.
The study is published in medical journal Clinical Cancer Research.
Dr Genovesi says the finding is "remarkable" because the tumours were very advanced and only treated for a short period of time without the use of chemotherapy.
"The beautiful thing with this drug is we tested it in two different genetic groups and it worked just as well. So we found a drug that as a single agent is highly effective and it works in multiple genetic sub-groups of paediatric tumours," Dr Genovesi told AAP.
The results mean Palbociclib, or drugs like it, could potentially be used against medulloblastoma in combination with other drugs to treat resistant cells.
"Because it's so good at shrinking the tumours immediately, it could be used first up to shrink the tumour so that the surgery would be less and the radiotherapy less," said Dr Genovesi.
"The key to it the fact that it worked so well on its own means that anything we really combine with it, it's only going to work better, it's an open door in that respect," she said.
