Scientists have discovered an enzyme in the “developmental pathway” of patients with embryonal tumors within multilayers rosettes – an uncommon but deadly childhood brain cancer – which they say may lead to more effective treatment of the disease.

The study, published in the journal Nature Genetics, was led by researchers from the Research Institute of the McGill University Health Centre (RI-MUHC), the McGill University and Génome Québec Innovation Centre and The Hospital for Sick Children (SickKids) in Canada.

According to the researchers, the brain cancer embryonal tumors within multilayers rosettes (ETMRs), also known as embryonal tumors with abundant neuropil and true rosettes (ETANTR), is only found in children under the age of four.

The investigators note that although the cancer is rare, it is almost always fatal, even though treatment for it is aggressive.

With this in mind, the researchers looked to determine what the driver was behind ETMR/ETANTR tumor growth.

They analyzed five large public data sets looking at patients with ETMR/ETANTR and created “genomic” profiles of the tumors.

From this, it was discovered that a process involved in early formation of an organ in an embryo – known as a “developmental pathway” – is “hijacked.” This causes production of an enzyme called DNMT3B much later during development, and in excessive quantities.

According to the researchers, forms of this enzyme have previously been found in some types of leukemia and breast cancers – and the enzyme is commonly linked to poor outcomes. Furthermore, DNMT3B has previously been linked to many cognitive problems.

The researchers discovered that patients with ETMR/ETANTR had DNMT3B in very large quantities, and also at a point of development when the enzyme should not be present at all.

The investigators say their findings suggest that DNMT3B could be a potential target for future therapies to treat ETMR/ETANTR, and the next steps will be to determine whether enzyme production can be controlled in the tumor and whether this could halt its growth.

Commenting on the study, co-principal investigator Dr. Nada Jabado, hemato-oncologist at the Montreal Children’s Hospital of the MUHC and an associate professor in the Department of Pediatrics at McGill University, says:

We undertook this study because we wanted to learn what was driving the growth of these tumors and how best to treat them.

This is a very aggressive disease with poor outcomes for patients; we urgently need better treatments for these kids, and this study, which helps us better understand what happens in this tumor, moves us a little closer to that target.”

Dr. Annie Huang, a brain tumor specialist at SickKids, led a research group in 2009 that initially discovered that several forms of deadly brain tumors in young children were actually ETMR/ETANTR.

She says that the collaborations in this most recent study have “provided opportunities to take our initial discovery of this entity closer to finding innovative treatments for this disease, which we believe is an important, yet under-recognized, infantile brain tumor.”