Evaluation of the efficiency of double recombinant vaccinia virus VV-GMCSF-Lact against glioblastoma using 3D spheroid and cerebral organoid models

Introduction: Human cerebral organoids (COs) are sophisticated three-dimensional (3D) models that successfully replicate the 3D cytoarchitecture of human brain development in its early stages. Co-cultivation of COs obtained from human-induced pluripotent stem cells with 3D U-87 MG glioblastoma cell spheroids (glioblastoma–CO assembloid [GCOA]) represents a robust strategy for modeling brain cancer behavior. Objectives: This study aims to evaluate the feasibility of using GCOAs and 3D U-87 MG glioblastoma cell spheroids as in vitro cell models to evaluate the cytotoxic effect of the oncolytic recombinant vaccinia virus-granulocyte–macrophage colony-stimulating factor (VV-GM-CSF)-Lact compared to the VV-GMCSF-del virus. Methods: To assess the cytotoxicity of two virus strains, we used fluorescent and confocal microscopy, spectrophotometry, the MTT assay, and real-time polymerase chain reaction Results: Glioblastoma cells died faster in the presence of VV-GMCSF-Lact virus, and 3D spheroids infected with this virus contained more caspase-3-positive cells. On the 10th day in GCOA, glioblastoma cells began to invade the interior of the CO. Under conditions of 3D spheroid and GCOA infection with recombinant viruses, three differentially expressed genes – FSCN1, SCUBE2, and TNFRSF9 – associated with invasion were analyzed. Conclusion: These 3D models of glioblastoma can be used in the development of antitumor drugs to study their cytotoxic effects.