Systematicand narrative reviews converge on the conclusion that while preclinicalanticancer activity of cannabinoids is plausible, robust clinicalproof of efficacy in GBM remains unestablished. At the same time, mechanistic work identifies CBD-responsivepathways (e.g., modulation of NF-κB activity) that could guidebiomarker-driven trials. Future studiesshould be adequately powered, stratified by molecular features (e.g.,MGMT status, IDH mutation), and integrate PK/PD, CNS penetration,steroid exposure, and tumor-microenvironment readouts. This evidence concerns the gene MGMT and neoplasm.