Immune Checkpoint Inhibitors in Glioblastoma Treatment

Abstract

Glioblastoma is one of the most aggressive primary brain tumors in adults. Despite intensive treatment, including surgery, radiotherapy, and chemotherapy using temozolomide, this type of tumor is characterized by rapid growth and development with subsequent complications. Due to the inefficiency of conventional treatment modalities, new effective targeted strategies need to be developed. The use of immune checkpoint inhibitors (ICIs) is an essential part of modern immunotherapy. The application of this drug has led to a fundamental shift in the treatment strategy of many advanced cancers because it can activate a natural immune reaction against tumor formation. Therefore, ICI is considered a new target for studying various types of oncological diseases. Nevertheless, in cases of glioblastoma, the efficacy of the therapy is reduced because of the immunosuppressive activity of the tumor microenvironment, low mutation frequency, and the blood-brain barrier. The paper considers the most common issues related to the use of ICIs in the treatment of glioblastoma and the prospective strategies that may improve the clinical picture of the disease. Special attention will be paid to the recent advances in combined treatment, alternative delivery pathways of ICIs used as adjuvant therapies, and the role of prognostic biomarkers. By combining immunotherapy with traditional clinical treatment methods and accurately screening the patients most likely to benefit, ICIS-based therapy is expected to provide new opportunities to prolong overall survival in patients with glioblastoma.