1,3,5-Tricaffeoylquinic Acid from Ipomoea batatas Vines Induced Ovarian Cancer Cell Apoptosis and Inhibited Endothelial Tube Formation.

Ovarian cancer usually metastasizes from the ovary to adjacent organs through direct invasion with blood vessels formed by endothelial cells. Targeting apoptosis of ovarian cancer and angiogenesis is promising for anticancer therapy. Leaves of Ipomoea sp. have reportedly shown promise in treating ovarian cancer. Here, we investigated the apoptosis-inducing and anti-angiogenic effects of compounds isolated from Ipomoea batatas vines (IBV). Phytochemical examination of IBV led to the isolation and verification of eight compounds (1-8): chlorogenic acid (1), 3,4-dicaffeoylquinic acid (2), 3,5-dicaffeoylquinic acid (3), 4,5-dicaffeoylquinic acid (4), 1,3,5-tricaffeoylquinic acid (5), N-trans-feruloyltyramine (6), scopoletin (7), and esculetin (8). Of these, 1,3,5-tricaffeoylquinic acid (5) showed the highest cytotoxicity in A2780 human ovarian cancer cells, inducing apoptotic death in more than 37% cells and decreasing viability to less than 25% at 100 μM. Compound 5 increased the levels of cleaved caspase-8, Bax, cleaved PARP, and caspase-3/9, and decreased the levels of cleaved Bcl-2. Further, 5 inhibited tubule formation in HUVECs. VEGFR2, ERK, PI3K, Akt, and mTOR protein expression was also suppressed by 5. Then, a simple, rapid, and reliable LC-MS/ MS method was developed to determine the contents of the isolated compounds from IBV. Overall, 5 has potential for treating ovarian cancer as it induces apoptosis in ovarian cancer cells and inhibits tube formation.