This article analyzes for the first time the effects of G721-0282, a CHI3L1 inhibitor, on the expression of proteins involved in intercellular junctions, such as E-cadherin, N-cadherin and VCAM-1, in GBM spheroids composed of glioblastoma U-87 MG cells, macrophages, and HMEC-1 endothelial cells. This evidence concerns the gene CHI3L1 and glioblastoma.