ANTI-ANGIOGENIC EFFECT OF 9-METHOXYCANTHIN- 6-ONE ISOLATED FROM EURYCOMA LONGIFOLIA ON ENDOTHELIAL CELL LINE

Abstract

Eurycoma longifolia Jack has been traditionally used in Southeast Asia for various ailments including cancer. Its bioactive quassinoids exhibit significant pharmacological properties. Among them, 9-methoxycanthin-6-one shows potential anti-cancer activity. However, its anti-angiogenic effects remain unexplored. This study evaluates its anti-angiogenic effects on EA.hy926 endothelial cells. Three assays (spheroid growth, tube formation, and cell migration) were performed, and data were analysed using one-way ANOVA with Dunnett’s test (p < 0.0001). Results show that 9-methoxycanthin- 6-one inhibited EA.hy926 proliferation (IC₅₀: 25.85 ± 1.29 μM) compared to suramin (IC₅₀: 60.94 ± 5.03 μM). In the spheroid assay, it significantly reduced spheroid diameter (88.73% at IC₅₀/8 to 82.63% at IC₅₀) at 48 hours, though inhibition at 96 hours was inconsistent, suggesting possible adaptive responses. No tube formation was observed at IC₅₀/2 and IC₅₀ after 6 and 18 hours. At lower concentrations (IC₅₀/8 to IC₅₀/4), tube length (93.84–134.75 μm) and width (17.77–20.65 μm) were significantly reduced. Cell migration was also inhibited (61.26 ± 8.05% at IC₅₀/8 to 19.19 ± 8.64% at IC₅₀) compared to NT (100%). Overall, 9-methoxycanthin-6-one exhibits significant anti-angiogenic potential supporting its role as an angiogenesis inhibitor in multiple in vitro models.