Large studies reveal improved treatment for children with Group 3 medulloblastoma

Vital research findings that point to improved treatment for children with Group 3 medulloblastoma brain tumors have been revealed in two major studies published in the journal Neuro-Oncology.

Medulloblastoma is one of the most common malignant brain tumors of childhood cancer and accounts for approximately 5 to 10% of childhood cancer deaths.

Now, findings from the two-phase £5 million INSTINCT studies could form the basis of more targeted treatments for many children, leading to improved survival, less severe long-term side effects and improved quality of life.

Led by Professor Steve Clifford, Director of the University of Newcastle Cancer Centre, the INSTINCT research project aimed to identify key genetic defects and find effective targeted approaches to treat Group 3 medulloblastoma.

Group 3 medulloblastomas are a group of tumors that occur primarily in young children and are effectively incurable, contributing significantly to overall childhood cancer mortality rates. This cancer is caused by the presence of a gene called MYC, which triggers the rapid development of the disease and often leads to treatment failure.

Gathering the largest cohort of MYC-amplified tumors ever studied—derived from more than 1,600 cases—the study demonstrated critical variation in clinical outcomes in this cohort.

They were able to identify for the first time specific groups of patients who are currently almost incurable and urgently need new approaches.

The two studies, which began in 2015, provided critical evidence to help guide diagnosis and consider appropriate treatment depending on the tumor’s genetic makeup.
The researchers also identified the potential for a new approach to treating the disease, using drugs that target the MYC gene’s effect on tumor growth.

Medulloblastomas with MYC gene amplifications are one of the greatest challenges in pediatric oncology. In our latest studies, we identified a significant group of these tumors that are essentially incurable using current therapies and how to identify them diagnostically.

New therapies are urgently needed to treat these tumors, but there has been a delay in their development. In our second new paper, we report our discovery that MYC tumors depend on a critical metabolic pathway—the serine/glycine synthesis pathway—for their growth and development, and that we can target this pathway using PHGDH inhibitor drugs in experimental models to slow tumor growth.

Together, these studies provide key diagnostic features that can be directly used to identify this critical tumor group in the clinic, as well as an important targetable mechanism for developing new therapies aimed at improving their outcomes.”

Professor Steve Clifford, Director of the Newcastle University Cancer Centre

Dr. Ed Schwalbe, Associate Professor of Bioinformatics and Biostatistics at Northumbria University, led the first part of the INSTINCT study, which identified a group of patients with a particularly poor prognosis, as well as other groups of patients whose disease is curable with current treatments. He said: “Understanding that children with MYC medulloblastomas have different outcomes helps us choose the best treatments and paves the way for new approaches to treating this devastating disease.”

Dr Magretta Adiamah, a developing postdoctoral researcher, led the second part of the study investigating targeted metabolic therapies for MYC medulloblastoma during her PhD at Newcastle University. He said: “Our study opens up the possibility of targeting MYC medulloblastoma through a metabolic vulnerability created by MYC itself. It is promising that we can selectively target MYC medulloblastoma by understanding what it needs to grow so aggressively.”

The studies were funded by Children with Cancer UK, Cancer Research UK, The Brain tumor Charity, Great Ormond Street Hospital Charity (GOSH Charity), Blue Skye Thinking and Little Hero.

Both Blue Skye Thinking and Little Hero were formed by families in memory of their lost sons who died of medulloblastoma. John Rainsbury, Trustee of Little Hero and Dad to Will who died of Group 3 medulloblastoma aged six, said: “As a family we are excited by the possibilities this discovery provides and we hope this new understanding can develop into essential treatments for other kids dealing with what Will went through.

“While diagnostics have advanced, the actual treatment for medulloblastoma has surprisingly changed little in 30 years, with the prognosis for high-risk variants remaining stubbornly poor. It is important to develop new approaches to target high-risk disease much more effectively and to give kids like Will a chance for the future.”

The head of Children’s Cancer Research UK, Dr. Sultana Choudhry, said: “We have a long-standing commitment to fund research to accelerate scientific breakthroughs into the clinical translation of new treatments and better outcomes for children with cancer.

“This study represents an important step toward more effective and targeted treatments for one of the most challenging forms of childhood brain cancer.

“Through funding vital research like the INSTINCT programmes, we continue to improve outcomes for children with cancer and work towards our vision of a world where every child and young person survives a cancer diagnosis.”