New Insights into Myeloid Immune Cells as Potential Targets for Liver Cancer Immunotherapy

Recent research has uncovered a significant breakthrough in understanding the immune landscape of hepatoblastoma, the most common liver cancer in children. Using advanced imaging techniques, scientists from the University Medical Center Utrecht and the Princess Máxima Center identified a high presence of myeloid immune cells within tumor tissues—cells that had previously been overlooked in pediatric liver cancers. These myeloid cells, which can be activated to attack tumor cells, open up new possibilities for immunotherapy strategies tailored for children.

Hepatoblastoma develops in children when immature liver cells fail to mature properly and begin dividing uncontrollably. Current treatments typically involve chemotherapy and surgical removal, often coupled with liver transplantation in severe cases. However, the prognosis hasn't improved significantly, highlighting the urgent need for innovative therapies.

Until now, the role of immune cells in hepatoblastoma was poorly understood. This study revealed that immune responses in these tumors differ markedly from adult liver cancers, particularly showing a scarcity of T cells—the immune cells commonly targeted in adult immunotherapy. Researchers employed spatial omics methods to accurately map immune cell populations and their locations within the tumor, providing detailed insights into the tumor microenvironment.

The discovery of abundant myeloid cells in these tumors suggests a potential new avenue for treatment. These cells, similar to T cells in their ability to be activated to destroy tumor tissue, could be targeted with future immunotherapeutic approaches. Furthermore, chemotherapy appears to increase the number of myeloid cells within the tumor, indicating the potential for combination therapies. Such an approach would involve initially using chemotherapy to attract immune cells, then activating them with immunotherapy to enhance tumor destruction.

Despite these promising findings, further research is essential. Currently, immunotherapy in pediatric liver tumors has primarily focused on T cells, with little attention given to myeloid cells. Ongoing studies in adults are exploring safety and effectiveness, and this knowledge may soon be translated to childhood cancers.

This collaborative effort exemplifies how combining clinical expertise with innovative molecular techniques can pave the way for personalized treatments. Understanding the immune profile of childhood tumors is crucial to developing new therapies that are both effective and tailored to the unique immune environment in pediatric patients.

For more details, see the full study published in Cancer Immunology, Immunotherapy: Daniëlle Krijgsman et al., "High-plex imaging of hepatoblastoma and adjacent liver in pediatric patients reveals a predominant myeloid infiltrate expressing immune-checkpoints," 2025.