Miao Zhao and Fredrik Swartling have shown that pediatric brain tumors from different parts of the brain share the same biological origin.
Photo Credit: Anjali Sivakumar
Scientific Frontline: Extended "At a Glance" Summary: Common Cellular Origin of Pediatric Brain Tumors
The Core Concept: Severe pediatric brain tumors that develop in entirely distinct anatomical regions—such as the pineal gland, retina, and cerebellum—actually arise from the same type of immature precursor cell containing photoreceptor features.
Key Distinction/Mechanism: While historically tumors like pineoblastoma, retinoblastoma, and medulloblastoma were viewed as biologically independent due to their varied anatomical locations, advanced molecular profiling demonstrates they share a unified origin in light-sensitive precursor cells. This mechanism distinguishes them biologically from other, unassociated tumors developing within those exact same brain regions.
Major Frameworks/Components:
- Single-Cell Analysis: The use of advanced molecular mapping to profile and compare the biological origins of diverse patient tumors.
- Photoreceptor Signature: The identification of specific proteins associated with light-sensitive cells that are preserved from evolutionary biology and act as drivers for tumor development across distinct central nervous system regions.
- CRISPR/Cas9 Validation: The utilization of genetic scissors in mouse models to block photoreceptor activity, successfully halting tumor growth and confirming the biological target.
Branch of Science: Pediatric Oncology, Neuro-oncology, Molecular Biology, and Genetics.
Future Application: This discovery establishes the groundwork for novel precision therapies that target photoreceptor-driven cells directly. It suggests that oncologists may soon be able to utilize similar, unified treatment protocols for tumors located in the pineal gland, the eye, and the cerebellum.
Why It Matters: Mapping the relationships between nearly a hundred different types of pediatric brain cancer simplifies a highly complex clinical landscape. Grouping these aggressive tumors by a common cellular origin allows for broader, cross-applicable medical treatments, ultimately improving therapeutic strategies and survival rates for children battling malignant central nervous system malignancies.
Researchers have discovered that severe brain tumors in children that appear to be completely different actually arise from the same type of cell. This cell type can give rise to tumors in the pineal gland, the retina, and the cerebellum. The discovery that these tumors are related may make it possible to treat them in similar ways.
Malignant brain tumors in children are typically treated through a combination of surgery, radiation therapy and chemotherapy, which today results in cure in roughly three out of four cases. In recent years, researchers have identified nearly a hundred different types of cancer in the brain, but the relationships between them have remained insufficiently mapped. For example, it has been unclear which tumor types are most closely related and might therefore be treated in similar ways.
Striking similarities to other tumors
In the new study, Fredrik Swartling and his research group at Uppsala University, together with international colleagues, investigated the development of pineoblastoma, a serious tumor originating from the pineal gland, a small pinecone-shaped structure located deep in the middle of the brain. When the researchers analyzed tumors from patients using advanced molecular methods, including single-cell analysis, and compared them with other tumor types, the results were unexpected: the tumors did not resemble other tumors from the same brain region. Instead, they showed striking similarities to tumors arising in entirely different parts of the brain, especially the eye tumor retinoblastoma, which arises in the retina at the back of the eye, and medulloblastoma, which forms from cells in the cerebellum, situated at the rear of the head.
“We observed, for example, that a tumor discovered in the pineal gland of a patient was so similar to a tumor typically found in the cerebellum that we initially suspected it might have spread from there. But this turned out not to be the case. The cells that gave rise to the tumors were biologically very similar to one another, despite originating in such different areas of the brain,” says Fredrik Swartling, one of the study’s senior authors.
Tumors could be treated in similar ways
In the pineoblastoma cases examined, the researchers found that the tumours originated from a particular type of immature precursor cell that also produced a protein commonly found in light-sensitive cells, namely, the cells of the retina.
“Cells that detect light for vision exist only in the eye in humans, but over the course of evolution and in other animal species, cells that respond to light or that retain so‑called photoreceptors are also found in other parts of the brain,” says researcher Miao Zhao, who performed the experimental cell and animal model studies in the laboratory.
It is precisely these cell types, cells that still carry features associated with photoreceptors, that appear capable of giving rise not only to retinoblastoma in the eye, but also to pineoblastoma and medulloblastoma in the developing brain in children. The researchers confirmed this connection in mouse models, where activation of these photoreceptor-driven cells triggered the development of pineoblastoma. Furthermore, if the photoreceptor activity was blocked using the genetic scissors CRISPR/Cas9, these tumors stopped growing.
“The fact that cells with photoreceptor activity are particularly prone to developing tumors suggests that we may be able to target them with future precision therapies. Our findings also indicate that tumors arising in the pineal gland and the cerebellum could in fact be treated in similar ways,” says Fredrik Swartling.
Additional information: The study is a collaboration between Uppsala University, St. Jude Children’s Research Hospital in Memphis, USA, Boston Children’s Hospital, USA, and researchers from Canada, Germany and Austria.
Published in journal: Cancer Cell
Title: A tumor-associated photoreceptor signature unifies distinct central nervous system malignancies
Authors: Brian L. Gudenas, Shiekh Tanveer Ahmad, Bernhard Englinger, Anthony P.Y. Liu, Miao Zhao, Leena Paul, Jennifer Hadley, Yiran Li,Melissa Batts, Priya Mitta, Stephanie C. Wu, Sara A. Lewis, Katie Han, Taha Soliman, Hong Lin, Laure Janke, David Meredith, Elke Pfaff, Johannes Gojo, Jennifer Cotter, Paul Klimo, Jr., Frederick A. Boop, Amar Gajjar, Giles W. Robinson, Gabriela Rosén, Sanda Alexandrescu, David T.W. Jones, Brent A. Orr, Fredrik J. Swartling, Mariella G. Filbin, and Paul A. Northcott
Source/Credit: Uppsala University | Sandra Gunnarsson
Reference Number: ongy030626_01
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