Heterogeneity of glucocorticoid receptor content in high-grade gliomas

Introduction. Morphological, molecular and genetic heterogeneity of glial tumors is considered a significant feature and is not yet widely employed in clinical practice. To reduce edema in the treatment of brain tumors, dexamethasone is used, which is a glucocorticosteroid and a glucocorticoid receptor agonist. The content of the receptor in high-grade gliomas and intact brain tissue has not been sufficiently studied. However, heterogeneity of glucocorticoid receptor content may be one of the parameters determining the heterogeneity of these gliomas. This paper aimed to study the content of the glucocorticoid receptor in Grade 4 gliomas in humans and SCID mice. Materials and methods. A retrospective study was performed on 51 patients operated on for Grade 4 glioma. The control group included samples from 23 patients with brain vascular malformations. The experimental group consisted of SCID mice that received human glioblastoma U87 cells. The control group was composed of intact SCID mice. We used the data of immunohistochemical staining using antibodies to the glucocorticoid receptor to calculate the integral score of marker content. Results. In both groups of patients, we identified 3 subgroups, i.e., with low, moderate, and high content of the glucocorticoid receptor. High receptor content was most often observed in the group of patients with glioma, while low and moderate receptor content was detected in the patients from the control group. The integral score of receptor content always showed statistically significant differences between the subgroups. In the in vivo experiment, the U87 tumors were characterized by an extremely high content of the glucocorticoid receptor, while in the control group, high and moderate protein content was observed in approximately equal proportions. Conclusion. Glioma Grade 4 is heterogeneous in the content of the glucocorticoid receptor. Transformation of the nervous tissue associated with the formation of high-grade glioma is accompanied by an increase in the expression of the glucocorticoid receptor. Keywords: glioma, tumor heterogeneity, intact brain tissue, glucocorticoid receptor