Geiparvarin is an anticancer agent that acts as an inhibitor of MAO-B (pIC50= 6.84 μM). It exerts its antitumor effects by downregulating COX2 expression and inhibiting angiogenesis. Geiparvarin halts the cell cycle at the G1 phase and induces apoptosis in cancer cells. Additionally, it exhibits antimicrotubule activity (Microtubule/Tubulin) and disrupts the cytoskeleton, contributing to its antiproliferative properties. Geiparvarin is of research interest for its potential effects on lung cancer, leukemia, and breast cancer.

MAO-B:6.84 μM (pIC50)

Geiparvarin (Compound 8) shows inhibitory effects on the proliferation of various human tumor cell lines, with IC 50 values of 5.7 μM for SHSY5Y, 6.3 μM for HL-60, 9.2 μM for K562, 9.8 μM for HT-1080, and 11.5 μM for A-549 over 72 to 48 hours. Geiparvarin (8 μM, 24-72 h) arrests the HL-60 cell cycle at the G1 phase and induces apoptosis independent of caspase. It exhibits complete inhibitory effects on drug-resistant cell lines, unaffected by drug-efflux transport proteins. Geiparvarin (1 μM, 24 h) inhibits invasion in HOS and 143B cells. In concentrations of 0.5-2 μM over 24-48 hours, it activates apoptotic pathways, inhibits COX2 and downstream angiogenic pathways, and induces caspase-dependent apoptosis in HOS and 143B cells. The compound exerts antitumor effects in osteosarcoma cells through COX2 downregulation, reversible by COX2 overexpression. Geiparvarin (10 μM, 24 h) disrupts the cytoskeleton, especially intermediate filaments, in Balb/c 3T3 fibroblasts. In rat liver mitochondrial extracts, geiparvarin (0.01-10 μM) shows a concentration-dependent inhibition of MAO-B, with a pIC 50 of 6.84 (IC 50 = 1.45 μM).

Geiparvarin (Compound 8) administered at 0.5 mg/kg intraperitoneally, every three days over several weeks/daily, inhibits tumor growth and lung metastasis in a xenograft model of 143B/9901 cells in nude mice, without showing significant toxicity.