Multi-omics integration and functional validation identify thrombospondin-1 as a functionally relevant mediator of...

Glioblastoma (GBM) exhibits highly infiltrative growth that limits therapeutic efficacy and promotes recurrence. Although doramectin (DRM) has been shown to induce apoptosis and autophagy in GBM cells, its effects on tumor migration and invasion remain unclear. We performed integrative transcriptomic and functional analyses to identify mediators associated with DRM anti-invasive activity. RNA sequencing of DRM-treated versus control rat C6 glioma cells identified 3747 differentially expressed genes, including 1660 upregulated and 2087 downregulated genes, with thrombospondin-1 (THBS1) markedly downregulated after DRM treatment (log2 fold change = -5.9). These genes were mainly associated with extracellular matrix organization, focal adhesion, phosphatidylinositol 3-kinase/protein kinase B (PI3K/Akt) signaling, and migration-related pathways. Public single-cell, spatial transcriptomic, and pan-cancer analyses provided contextual evidence of heterogeneous expression across tumor cellular and spatial contexts and is associated with tumor-related functional states. Under matched 24 h conditions, 5-20 μM DRM dose-dependently suppressed glioma cell adhesion, wound closure, migration, and invasion, with 20 μM DRM reducing Transwell migration and invasion by approximately 82-93% relative to the corresponding 0 μM control group. THBS1 knockdown reduced migration and invasion, whereas THBS1 overexpression partially restored migration and invasion under DRM treatment; these effects were accompanied by changes in matrix metalloproteinase 2 and matrix metalloproteinase 9 (MMP2 and MMP9) expression and focal adhesion kinase (FAK)/Akt phosphorylation. Collectively, THBS1 is functionally associated with GBM invasive phenotypes and may contribute to the anti-invasive effects of DRM, with extracellular matrix remodeling and FAK/Akt-related phosphorylation changes representing plausible associated processes.