Study of histological features of the stroma of high-grade gliomas depending on the mutation status of the <i>IDH</i> gene

Gliomas are characterized by extremely aggressive growth and resistance to therapy. The tumor progression is known to be closely linked to its microenvironment, with stromal characteristics playing a key role. The aim of the study was to investigate the features of mesenchymal stroma in high-grade gliomas. A retrospective study was conducted on biopsy specimens from 31 patients with grade 4 astrocytic tumors at the A.L. Polenov Russian Scientific Research Institute of Neurosurgery. Based on molecular profiling, 10 patients were diagnosed with IDH-mutant astrocytoma, and 21 patients were diagnosed with IDH-wildtype glioblastoma. The tumor stroma was assessed using immunohistochemical (IHC) staining for IDH1R132h and vimentin and histochemical staining with Alcian Blue, Toluidine Blue, and Mallory’s trichrome. Analysis revealed statistically significant differences between the groups for all histochemical stains (p 0.05, Student’s t-test). The presence of desmoplastic stroma and high vimentin expression indicates a glial-mesenchymal transition in IDH-wildtype glioblastoma, which underlies its aggressive progression.