Lab research suggests experimental drug could target neuroblastoma

In collaboration with the Press Association

A new class of drugs that have shown promise for the treatment of infant leukaemia may also work against another childhood cancer called neuroblastoma, according to laboratory research.

US researchers have shown that the drugs, known as BET bromodomain inhibitors, could be used to treat patients who's neuroblastoma is caused by a particular genetic defect.

BET bromodomain inhibitors (BET inhibitors) are an example of a new wave of experimental treatments called 'epigenetic' drugs.

They work by mimicking chemical 'tags' on the structures around DNA. These tags - called epigenetic markers - affect the activity levels of specific genes.

Study author Professor Kimberly Stegmaier, from Dana-Farber/Children's Hospital Cancer Center, said that many researchers have been hoping that BET bromodomain inhibitors could lead to new ways to treat certain cancers.

But the problem so far has been identifying which patients are most likely to respond to the drugs, she explained.

Professor Stegmaier and her colleagues looked at more than 600 types of cancer cells grown in the lab to see which might be sensitive to BET inhibitors.

Their findings, published in the journal Cancer Discovery, showed that neuroblastoma cells with extra copies of a gene called MYCN were sensitive to the drugs.

Professor Stegmaier explained that although extra copies of MYCN have been found in samples from a significant proportion of neuroblastoma patients, it has proven to be an "elusive drug target".

The researchers then looked at the effects of BET inhibitors on lab-grown neuroblastoma cells with extra MYCN, and in a mouse model of neuroblastoma that is resistant to many standard treatments.

They discovered that the drug reduced MYCN protein levels in lab-grown neuroblastoma cells, slowing down their growth and causing cell death.

The drug also shrunk tumours and prolonged survival in mice.

Dr Kat Arney, science information manager at Cancer Research UK, said: "We urgently need more effective treatments for children with neuroblastoma, and this research opens up an exciting new avenue.

"Cancer Research UK scientists have already shown that BET inhibitors might be effective against some types of leukaemia, and these results add another potential use of these promising drugs."

"But they are very new and have so far only been tested in the lab, so more work needs to be done to show whether they might help patients in the future."

Copyright Press Association 2013