The Aptamer bi-(AID-1-T) Synergizes with Radiation to Inhibit Proliferation of Human Glioma Cells

Background: High-grade gliomas are treatment-resistant and prone to aggressive recurrence. Although radiation therapy is a fundamental treatment, it often fails to eradicate tumors and can enhance the migratory potential of surviving cells, promoting relapse. Anti-proliferative aptamers are novel agents that show promise, but their combination with radiation therapy and their effects on invasive phenotypes require further investigation. Objectives: This study evaluated the effects of ionizing radiation on the viability and migration of human glioma cells, both alone and in combination with the anti-proliferative aptamer bi-(AID-1-T). The study aimed to determine whether the aptamer could enhance the efficacy of radiotherapy and counteract ionizing radiation-induced pro-migratory effects. Methods: The study was conducted on cell cultures of primary and relapsed human glioma. The effects of combined radiation (single dose of 20 Gy) and the bi-(AID-1-T) aptamer (10 μM) were assessed using the MTS assay, Transwell analysis, immunocytochemistry and transcriptome analysis. Results: Ionizing radiation alone reduced proliferation in primary gliomas, but increased proliferation in recurrent cultures. Ionizing radiation also increased migration in both types of gliomas. Combining ionizing radiation with the bi-(AID-1-T) aptamer produced a synergistic effect: it significantly reduced cell proliferation and migration, and suppressed the ionizing radiation-induced migratory enhancement, more effectively than either treatment alone. Transcriptome analysis revealed that combination treatment decreased the expression of pro-proliferative and migratory genes (e.g., PDPN, CDH3), while increasing the expression of anti-migratory (RND3) and pro-apoptotic genes (e.g., XAF1, SEMA3A). Thus, combination treatment significantly reduces tumor cell proliferation and migration; however, further studies on surviving cells are needed.