A water-soluble polysaccharide from the roots of Polygala tenuifolia suppresses ovarian tumor growth and angiogenesis in vivo

PTP, one polysaccharide extracted from the roots of Polygala tenuifolia, has displayed anti-cancer activity in several types of ovarian cancer cells. This study aims to elucidate the structure of PTP and investigate its anticancer effects against SKOV3 xenograft tumor growth in BALB/c mice, as well as the underlying mechanisms involved. GC-MS and NMR data indicate that PTP has a backbone composed of 1,4,6-linked-β-Galp, 1,4-linked-β-Galp and 1,4-linked-β-Glcp, with non-reducing terminal 1-linked-α-Glcp attached to O-6 of 1,4,6-linked-β-Galp. The tumor growth was suppressed in mice following two week's PTP administration (10, 20 and 40 mg/kg) due to the induction of apoptosis, as detected by TUNEL assay. Moreover, lower serum VEGF and EGFR levels were observed in BALB/c mice treated with different doses of PTP when compared with that in untreated mice. Also, EGFR, VEGF, and CD34 were decreased in both transcript and protein levels in the tumor-bearing mice upon PTP treatment. Taken together, our data suggest that PTP appears to be a powerful chemopreventive agent for the patients with ovarian cancer, especially at advanced stage.