Background: Glioblastoma is one of the most aggressive tumors of central nervous system. Galbanic acid, a natural sesquiterpene
coumarin, has shown favorable effects on cancerous cells in previous studies.
Objective: The aim of the present work was to evaluate the effects of galbanic acid on proliferation, migration, and apoptosis of the human
malignant glioblastoma (U87) cells.
Methods: Anti-proliferative activity of the compound was determined by MTT assay. Cell cycle alterations and apoptosis were analyzed via
flow cytometry. Action on cell migration was evaluated by scratch assay and gelatin zymography. Quantitative Real-Time PCR was used to
determine the expression of genes involved in cell migration (matrix metalloproteinases, MMPs) and survival (the pathways of PI3K/Akt/mTOR
and WNT/β-catenin). Alteration in the level of protein Akt was determined by Western blotting.
Results: Galbanic acid significantly decreased cell proliferation, inhibited cell cycle, and stimulated apoptosis of the glioblastoma cells. Also,
it could decrease migration capability of glioblastoma cells, which was accompanied by an inhibition in the activity and expression of MMP2
and MMP9. While galbanic acid reduced the gene expression of Akt, mTOR, and PI3K and increased the PTEN expression, it had no significant
effect on WNT, β-catenin, and APC genes. Also, the protein level of p-Akt decreased after treatment with galbanic acid. The effects of galbanic
acid were observed at concentrations lower than those of temozolomide.
Conclusion: Galbanic acid decreased proliferation, cell cycle progression, and survival of glioblastoma cells through inhibiting
PI3K/Akt/mTOR pathway. This compound also reduced migration capability of the cells by suppressing the activity and expression of MMPs.