Glioblastoma and Cerebral Organoids: Development and Analysis of in vitro Model for Glioblastoma Migration

It is currently challenging to adequately model the growth and migration of glioblastoma using 2D in vitro culture systems as they quickly lose the original, patient-specific identity and heterogeneity. However, with the advent of 3D cell cultures and human induced pluripotent stem cells (iPSCs)-derived cerebral organoids (COs), studies demonstrate that the glioblastoma-cerebral organoid (GLICO) co-culture model helps to preserve the phenotype of the patient-specific tissue. Here we aimed to set up such a model using mature COs and develop a pipeline for subsequent analysis of co-cultured glioblastoma. Our data demonstrates that the growth and migration of the glioblastoma cell line within the mature COs are significantly increased in the presence of extracellular matrix proteins, shortening the time needed for glioblastoma to initiate migration. We also describe in detail the method for the visualization and quantification of these migrating cells within the GLICO model. Lastly, we show that this co-culture model (and the human brain-like microenvironment) can significantly transform the gene expression profile of the established U87 glioblastoma cell line into proneural and classical glioblastoma cell types. Comparative gene expression analysis of three biological replicates of GFP+ cells sorted from of GLICO model (each sample consisting of 5 GLICOs; co-cultivation for 40 days) and controls - three biological replicates of U87-GFP spheroids cultivated alone without co-culture with cerebral organoids.