By analyzing single-cell and spatial transcriptomic data from myeloid cells from 85 brain tumors, scientists from McGill University, the Broad Institute, and elsewhere found that a commonly prescribed anti-swelling drug, dexamethasone, suppresses the immune system for weeks after dosing, inhibiting its response to the cancer. The findings could open a door to more effective strategies for managing cancer-related inflammation in the brain as well as improved immunotherapies. Full details were published in a Nature paper titled, “Programs, origins and immunomodulatory functions of myeloid cells in glioma.
” In it, the researchers explain that they used single-cell and spatial data to learn how myeloid cells affect the immune system’s response to gliomas, tumors that develop in the brain or spinal cord. “In gliomas, myeloid cells are the most prevalent non-malignant cell type, comprising up to 50% of cells in a tumor,” the researchers wrote in Nature. “Tumor-associated myeloid cells can influence the molecular state of malignant cells as well as tumor-infiltrating T cells .
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They can also recruit and suppress other myeloid cells.”The study data revealed a consistent organization of cells within brain cancer, where each type of myeloid cell was found in specific areas and tailored to its role in the tumor. Notably, the researchers identified two types of immunosuppressive myeloid cells.
In patients treated with dexamethasone, these specific cell types had a signifi.
